Question 1

A 27-year-old woman comes to the office for an annual physical examination.  She currently works as a medical interpreter in a regional hospital.  The patient feels well and has no medical problems.  Her only medication is a daily oral contraceptive pill.  She does not use tobacco, alcohol, or illicit drugs.  The patient is up to date with recommended vaccinations and has had no known contact with a person infected with tuberculosis.  Vital signs are within normal limits.  Mucous membranes are moist and without lesions.  Lung fields are clear to auscultation and heart sounds are normal.  The abdomen is soft and nontender with no organomegaly.  No skin rash is present.  A tuberculin skin test is performed and produces a 12-mm induration at 48 hours.  Chest radiography is normal, and urine pregnancy testing is negative.  The patient receives counseling and initiation on anti-tuberculosis therapy.  Which of the following is the most appropriate employment-related recommendation for this patient?

Accepted Answer

Explanation: 11ec2b69_bfc6_ccf8_8f63_abf7dc348006_MD0005_00 All health care personnel (HCP) should receive regular (eg, annual) screening for tuberculosis (TB) with a tuberculin skin test (TST) or interferon-gamma release assay. HCP who have a TST with >10-mm induration at 48 hours are likely to be infected with Mycobacterium tuberculosis and should undergo a chest x-ray. Those with no chest x-ray abnormalities and no symptoms (eg, weight loss, night sweats, chronic cough) are considered to have latent tuberculosis infection (LTBI). LTBI is noninfectious. LTBI screening should only be offered if treatment would be considered because, for most patients, the lifetime risk of advancing to active TB is small (5%-10%). Treatment (eg, 6-9 months of isoniazid) should be offered to affected individuals who are at higher risk of developing active TB (eg, immunosuppressed individuals) or those who reside (eg, inmates) or work (eg, HCP) in high-risk congregate settings. Because LTBI is noninfectious, affected individuals, including HCP, may continue to work (even if they decline or do not complete treatment); they do not require precautions (eg, N95 mask) or an absence for a full course of treatment . (Choice B) Patients treated for active TB are considered noninfectious when 3 consecutive acid-fast bacilli sputum smears are negative (8-24-hour intervals and >1 early morning samples). This patient does not require acid-fast bacilli smears as she has LTBI (no symptoms or chest x-ray abnormality). (Choice E) Patients exposed to TB several years prior may have false-negative initial tuberculin skin testing. As such, most organizations recommend 2-step pre-employment testing for LTBI; individuals with negative initial skin tests should have repeat testing in 1-3 weeks. This patient with a positive tuberculin skin test does not require repeat skin testing. Educational objective: Health care personnel (HCP) should be screened for tuberculosis on a regular basis. Infection is likely if skin testing shows >10-mm induration at 48 hours. Those with no symptoms and a normal chest x-ray are considered to have latent tuberculosis infection (LTBI). LTBI is noninfectious, and individuals may continue their normal daily lives without restrictions. However, because HCP work in congregant settings, treatment (eg, isoniazid) should be offered. References: Treatment of latent tuberculosis infection. (http://www.ncbi.nlm.nih.gov/pubmed/24056289) Drugs for tuberculosis. (http://www.ncbi.nlm.nih.gov/pubmed/22450707)

Question 2

An 8-year-old girl is brought to the office by her mother for evaluation of possible tuberculosis (TB).  The patient's younger brother was recently diagnosed with active pulmonary TB, which he contracted from their grandmother.  The patient has been in close contact with her brother but has had no fever, night sweats, cough, anorexia, or weight loss.  She had a negative TB skin test at the time of immigration from Southeast Asia 2 years ago.  The patient has not received the bacille Calmette-Guérin vaccine but is up to date with other recommended vaccinations.  Vital signs are within normal limits and physical examination shows no abnormalities.  Interferon-gamma release assay is positive and chest radiography is normal.  Cultures from a gastric aspirate of her younger brother show acid-fast bacilli that are resistant to isoniazid (INH) but are sensitive to other anti-TB drugs.  Which of the following is the most appropriate management for this patient?

Accepted Answer

Explanation: This patient with a positive interferon-gamma release assay has no symptoms or chest x-ray findings of active tuberculosis (TB), indicating latent tuberculosis infection (LTBI). Patients with LTBI receive empiric treatment without microbial isolation. As such, providers must rely on drug-susceptibility results of the likely source case (if available) to help guide treatment decisions. This patient likely acquired the infection from close contact with her brother. He has known pulmonary TB with an isoniazid-resistant strain (in children, gastric lavage sampling is often performed instead of induced sputum). As such, first-line therapy with daily isoniazid for 9 months is unlikely to be effective (Choice D). Instead, this patient should receive alternate therapy with daily rifampin for 4-6 months. (Choice A) Active pulmonary TB is often treated with multidrug therapy consisting of isoniazid, rifampin, pyrazinamide, and ethambutol for 2 months followed by isoniazid and rifampin for 4 months. Active pulmonary TB is marked by symptoms (eg, cough >3 months, weight loss, fever) and/or chest x-ray findings (eg, cavitation, infiltrate). This asymptomatic patient with a normal chest x-ray has LTBI, not active TB. (Choice B) Patients with a positive tuberculosis screening test usually have positive testing for life. Waiting 2 months to repeat an interferon gamma release assay would provide little clinical information and cause an unnecessary treatment delay. (Choice C) Sputum (or gastric lavage) acid-fast bacilli testing and mycobacterial culture are required only for patients with active pulmonary TB. This patient has LTBI, not active pulmonary TB. Educational objective: Children with latent tuberculosis infection require treatment to prevent conversion to active disease. Daily isoniazid for 9 months is the standard of care. If isoniazid resistance is suspected, the best alternate therapy is daily rifampin for 4-6 months.

Question 3

A 26-year-old man comes to the office after learning that one of his sexual partners tested positive for HIV.  The patient has had intermittent headaches, malaise, nausea, and blurry vision over the last several weeks.  He has had no fever, sore throat, skin rash, genital lesions, or weight loss.  The patient has no prior history of sexually transmitted infections or chronic medical problems.  He smokes a pack of cigarettes daily, consumes alcohol occasionally, and does not use illicit drugs.  The patient has had multiple sexual partners over the last several years and does not use condoms consistently.  Temperature is 37.1 C (98.8 F), blood pressure is 122/74 mm Hg, and pulse is 72/min.  There is no scleral icterus, oropharyngeal lesions, or skin rash.  Mild, generalized lymphadenopathy is present.  Cardiopulmonary and abdominal examinations are normal.  Cranial nerves, deep tendon reflexes, and sensation are normal.  No nuchal rigidity is present.  Ophthalmologic examination reveals no abnormalities.  Screening HIV immunoassay is positive.  Other laboratory studies are as follows:  A subsequent fluorescent treponemal antibody absorption test is positive.  Contrast-enhanced CT scan of the head reveals no space-occupying lesions. Additional tests are performed and are normal.  Which of the following is the best treatment option?

Accepted Answer

Explanation: 11ec2b69_bfc3_989f_8f63_5ff292f5af17_MD0005_00 Syphilis infections are characterized by periods of latency and periods of active disease. Treatment must be targeted to the current stage of illness, which is typically determined by: Symptoms Duration of infection (if known) Cerebrospinal fluid (CSF) evidence of neurosyphilis This patient with positive syphilis serology has no clear evidence of primary (eg, chancre), secondary (eg, diffuse rash, condylomata lata), or tertiary (eg, neurosyphilis, aortitis) syphilis, indicating latent infection. As the duration of his infection is unknown, he should be treated with intramuscular benzathine penicillin G weekly for 3 weeks. (Choice A) Patients with primary, secondary, or early latent syphilis (<1 year duration) should receive a single dose of intramuscular benzathine penicillin G. (Choice C) Patients with neurosyphilis or ocular syphilis require intravenous aqueous crystalline penicillin G for 10-14 days. Although this patient has blurry vision, his ocular and CSF evaluations are normal; therefore, he does not require treatment for ocular or neurosyphilis. (Choice D) Patients with tertiary syphilis (other than neurosyphilis) who have anaphylactic reactions to penicillin can be treated with 2 weeks of ceftriaxone. This patient has no evidence of tertiary syphilis and no history of penicillin allergy. (Choice E) Patients with anaphylactic penicillin allergies who have late latent syphilis or latent syphilis of unknown duration can receive alternate treatment with doxycycline for 28 days. This patient has no history of penicillin allergy; he should receive penicillin, not doxycycline, to reduce risk of treatment failure. Educational objective: Latent syphilis is defined as serologic evidence of infection with no clear evidence of primary, secondary, or tertiary disease. Patients with late latent syphilis (infection >1 year) or latent syphilis of unknown duration are treated with intramuscular benzathine penicillin G weekly for 3 weeks. References: Treatment of syphilis in HIV-infected subjects: a systematic review of the literature. (http://www.ncbi.nlm.nih.gov/pubmed/20924048) Response of HIV-infected patients with syphilis to therapy with penicillin or intravenous ceftriaxone. (http://www.ncbi.nlm.nih.gov/pubmed/21463980)

Question 4

A 3-year-old girl is brought to the emergency department due to pain and fever. Two days ago, she developed mild abdominal and back pain. Her fever began yesterday morning and reached a maximum of 40.1 C (104.2 F) last night. Over the last 8 hours, she had 6 episodes of emesis but has since tolerated a few sips of water. The girl has a history of constipation since the start of toilet training at age 2 and has "pellet-like" stools once a week. She has frequent urinary accidents during the day and night. She takes no medications and has no other medical problems. Immunizations are up to date. Temperature is 40 C (104 F), blood pressure is 90/60 mm Hg, pulse is 110/min, and respirations are 20/min. Physical examination shows a tired-appearing girl with dry mucous membranes. She has right costovertebral tenderness. The abdomen is soft, nontender, and nondistended. The remainder of the examination is unremarkable. Laboratory results are as follows: A 20-mL/kg normal saline bolus is administered. The patient has another episode of emesis and an additional void in the emergency department. Item 1 of 2 Which of the following best describes the appropriate management plan for this patient?

Accepted Answer

Explanation: 11ec2b69_bfcc_243a_8f63_0355a6a677e5_MD0005_00 Pyelonephritis is a kidney infection that typically presents with fever, nausea/vomiting, and flank/suprapubic pain. Additional findings include costovertebral angle tenderness, pyuria (eg, leukocyte esterase on dipstick analysis or >5 WBC/hpf on microscopy), and bacteriuria. Risk factors include female sex and a history of bladder and bowel dysfunction, as in this girl with chronic constipation. Initial management of suspected urinary tract infections (UTIs), including pyelonephritis, includes empiric systemic antibiotic therapy (eg, 3rd-generation cephalosporins). Intravenous antibiotics are indicated for patients with hemodynamic instability, the inability to tolerate oral medications (ie, persistent vomiting), or failure of improvement on oral antibiotics. Infants age <2 months are at increased risk of sepsis and should also be initially treated intravenously (Choice B). (Choice A) Renal ultrasound is indicated in children with febrile or recurrent UTIs. Imaging should be performed after completion of treatment as renal inflammation during acute illness can lead to false-positive results. (Choice C) The height of the fever does not influence the decision to treat with oral versus intravenous antibiotics if the patient is otherwise hemodynamically stable. Persistent fevers in a patient on oral therapy could warrant intravenous therapy. (Choice E) Oral antibiotics are first-line therapy for a UTI in a hemodynamically stable child with the ability to tolerate oral medications. This patient requires intravenous therapy to ensure adequate delivery of medication and can be transitioned to oral therapy if oral intake improves. Educational objective: Pyelonephritis is a kidney infection that presents with fever, nausea/vomiting, and flank pain. Intravenous antibiotics are indicated for patients who are unable to tolerate oral medication, have failed oral antibiotics, or are hemodynamically unstable. References: Antibiotics for acute pyelonephritis in children. (http://www.ncbi.nlm.nih.gov/pubmed/25066627) Randomised trial of oral versus sequential intravenous/oral cephalosporins in children with pyelonephritis. (http://www.ncbi.nlm.nih.gov/pubmed/18074149)

Question 5

A 30-year-old woman, gravida 1 para 0, at 34 weeks gestation comes to the office for a prenatal visit. The patient reports no abdominal pain, vaginal bleeding, or leakage of fluid. Fetal movement is normal. The patient has had urinary frequency throughout her pregnancy, but it has worsened over the last 4 days and is now associated with dysuria. She has no fevers, chills, nausea, vomiting, back pain, or hematuria. The pregnancy has been uncomplicated. The patient has no history of chronic medical conditions and has had no previous surgery. She takes a daily prenatal vitamin. The patient smokes half a pack of cigarettes a day but does not use alcohol or illicit drugs. Temperature is 36.7 C (98.0 F), blood pressure is 126/78 mm Hg, pulse is 76/min, and respirations are 18/min. BMI is 28 kg/m². Fetal heart rate is 140/min. On physical examination, the uterus is nontender and fundal height is 34 cm. Suprapubic tenderness is elicited with deep palpation. There is no costovertebral angle tenderness. Laboratory results are as follows: The patient is prescribed an appropriate antibiotic, and a clean-catch urine sample is obtained and sent for culture. The following day, the patient comes to the emergency department with fever, chills, nausea, and flank pain. Temperature is 38.3 C (101 F), blood pressure is 110/70 mm Hg, pulse is 96/min, and respirations are 16/min. The fetal heart rate tracing has a baseline of 170/min, moderate variability, multiple accelerations, and no decelerations. Tocometer shows no contractions. The left costovertebral angle is tender to palpation. Abdominal examination reveals a gravid, nontender uterus and no abdominal tenderness. A digital cervical examination reveals the cervix to be closed, long, and posterior. There is trace pedal edema over the bilateral lower extremities to the knees. Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bfcb_87f7_8f63_cf7d564533a3_MD0005_00 This patient now has fever, nausea, flank pain, and costovertebral angle tenderness, a presentation consistent with acute pyelonephritis. Risk factors for acute pyelonephritis during pregnancy include age <20, nulliparity, pregestational diabetes mellitus, sickle cell disease or trait, and tobacco use. Complications of acute pyelonephritis in pregnancy include pulmonary edema, acute respiratory distress syndrome, and preterm labor. Pyelonephritis can also cause renal abscess, papillary necrosis, and renal failure. Due to the risk for complications, pyelonephritis during pregnancy requires hospitalization for intravenous hydration and empiric treatment with broad-spectrum β-lactam antibiotics (eg, ceftriaxone, cefepime). Once afebrile for 48 hours, patients are placed on oral antibiotics for 10-14 days. After treatment completion, daily suppressive therapy (eg, low-dose nitrofurantoin or cephalexin) is initiated and is maintained until 6 weeks postpartum to prevent recurrence. (Choices A and E) Outpatient management of patients with pyelonephritis during pregnancy is not recommended due to the risks of complications (eg, pulmonary edema). In addition, nitrofurantoin does not achieve adequate renal levels and is not used to treat pyelonephritis. Trimethoprim-sulfamethoxazole use in the first trimester is associated with birth defects (eg, neural tube defects) and in the late third trimester with neonatal kernicterus. (Choice C) Ciprofloxacin, a fluoroquinolone, is effective in treating uncomplicated pyelonephritis in nonpregnant patients. Fluoroquinolones are avoided during pregnancy as they are toxic to fetal cartilage development. (Choice D) A renal ultrasound is indicated to evaluate for nephrolithiasis or a renal abscess in patients who are still febrile despite 48-72 hours of broad-spectrum antibiotics. Educational objective: Pyelonephritis presents with fever and costovertebral angle tenderness. Treatment during pregnancy involves hospitalization and broad-spectrum β-lactam antibiotics (eg, ceftriaxone). References: Pyelonephritis in pregnancy: an update on treatment options for optimal outcomes. (http://www.ncbi.nlm.nih.gov/pubmed/20731473)

Question 6

A 4-year-old girl is brought to the emergency department due to fever and lethargy. Her parents say she has been withdrawn and less playful over the last 2 weeks. She has also had several days of low-grade fever and headaches. Since yesterday morning, the patient has mostly slept and seems to be increasingly confused. She has no significant prior medical problems and is up to date with recommended vaccinations. Her grandfather, who is visiting the family from South Asia, is being evaluated for cough; otherwise, the patient has no sick contacts. The family has a pet cat. Temperature is 38 C (100.4 F). The patient is somnolent and responds to painful stimuli. There is resistance to passive neck flexion. Her right eye is deviated medially, and funduscopic examination reveals several ill-defined, raised, yellow-white nodules near the bilateral optic discs. CT scan of the head reveals basilar meningeal enhancement. Lumbar puncture is performed, and cerebrospinal fluid analysis results are as follows: Item 1 of 2 Which of the following is most likely to yield the diagnosis in this patient?

Accepted Answer

Explanation: 11ec2b69_bfc7_693b_8f63_2b453b273a0c_MD0005_00 This patient likely has tuberculous meningitis, a highly fatal form of extrapulmonary tuberculosis (TB). Manifestations typically begin with 2-3 weeks of prodromal symptoms (eg, headache, low-grade fever, lassitude) followed by progressive signs of meningeal irritation (eg, nuchal rigidity, vomiting, confusion). Cranial nerve palsies, coma, and seizures may occur. Choroidal tubercles (yellow-white nodules near the optic disc) are often detected via funduscopic examination. Suspicion for tuberculous meningitis is typically raised when brain imaging reveals basilar meningeal enhancement and cerebrospinal fluid (CSF) examination shows the following: Elevated protein (>250 mg/dL, generally 100-500 mg/dL) Low glucose (<10 mg/dL) Lymphocytic pleocytosis Elevated adenosine deaminase Definitive diagnosis requires serial lumbar punctures with CSF examination for acid-fast bacilli using smear and culture. (Choice B) Cytomegalovirus can cause a mononucleosis-type syndrome with fever, malaise, and lymphadenopathy. Retinitis and encephalitis may occur but are rare in patients with intact immunity. This patient with basilar meningeal enhancement and choroidal tubercles likely has tuberculous meningitis. (Choice C) Cryptococcal meningitis can be diagnosed with India ink preparation of CSF. Although most cases occur in patients with advanced HIV, immunocompetent individuals can develop subacute meningitis from Cryptococcus in rare cases. Basilar meningeal enhancement is uncommon. (Choice D) Toxoplasmosis infection is usually asymptomatic in immunocompetent individuals, but it may occasionally cause a mild systemic illness. Encephalitis is rare and usually associated with multiple ring-enhancing lesions on brain imaging. (Choice E) West Nile virus can cause systemic symptoms and meningitis in children. However, manifestations are typically acute, retinitis is uncommon, and brain imaging does not usually reveal basilar meningeal enhancement. Educational objective: Tuberculous meningitis typically causes 2-3 weeks of prodromal symptoms followed by signs of meningeal irritation. Suspicion is often raised in patients with choroidal tubercles, basilar meningeal enhancement, and characteristic cerebrospinal fluid (CSF) findings. Diagnosis typically requires serial lumbar punctures with CSF examination for acid-fast bacilli using smear and culture.

Question 7

A 30-year-old woman, gravida 1 para 0, at 34 weeks gestation comes to the office for a prenatal visit. The patient reports no abdominal pain, vaginal bleeding, or leakage of fluid. Fetal movement is normal. The patient has had urinary frequency throughout her pregnancy, but it has worsened over the last 4 days and is now associated with dysuria. She has no fevers, chills, nausea, vomiting, back pain, or hematuria. The pregnancy has been uncomplicated. The patient has no history of chronic medical conditions and has had no previous surgery. She takes a daily prenatal vitamin. The patient smokes half a pack of cigarettes a day but does not use alcohol or illicit drugs. Temperature is 36.7 C (98.0 F), blood pressure is 126/78 mm Hg, pulse is 76/min, and respirations are 18/min. BMI is 28 kg/m². Fetal heart rate is 140/min. On physical examination, the uterus is nontender and fundal height is 34 cm. Suprapubic tenderness is elicited with deep palpation. There is no costovertebral angle tenderness. Laboratory results are as follows: Item 1 of 2 Which of the following is the most appropriate medication for this patient's condition?

Accepted Answer

Explanation: 11ec2b69_bfca_ebb4_8f63_33e7448b24a0_MD0005_00 During pregnancy, physiologic changes such as increased urine output and compression of the bladder by the gravid uterus often cause symptoms of urinary frequency and urgency. However, this patient also has dysuria and a urinalysis positive for bacteria and leukocyte esterase, a presentation consistent with acute cystitis. The most common pathogen for acute cystitis is Escherichia coli. Other less common pathogens include Proteus mirabilis and Klebsiella pneumoniae. Risk factors for urinary tract infection in pregnancy include the presence of asymptomatic bacteriuria, nulliparity, pregestational diabetes mellitus, and tobacco use. Pregnant patients with clinically suspected acute cystitis are treated empirically with antibiotics for 3-7 days. First-line antibiotics include nitrofurantoin, cephalexin, fosfomycin, and amoxicillin-clavulanate. A urine culture is obtained to confirm infection and to direct the modification of the antibiotic regimen should symptoms not improve with treatment. Because there is a high risk of persistent bacteriuria, a urine culture is repeated for a test of cure one week after treatment completion. (Choice B) Ciprofloxacin, a fluoroquinolone, is effective in treating acute cystitis in nonpregnant patients. Fluoroquinolones are avoided during pregnancy as they are toxic to fetal cartilage development. (Choice C) Clindamycin covers gram-positive and anaerobic bacteria. Because it does not cover gram-negative bacteria, it is not typically used to treat acute cystitis. (Choice D) Tetracyclines are avoided in pregnancy as they cross the placenta, impair fetal long-bone development, and stain fetal teeth. (Choice E) Trimethoprim-sulfamethoxazole is a first-line treatment for cystitis in nonpregnant women. However, its use in the first trimester has been associated with neural tube defects due to the folate antagonist properties of trimethoprim. Use in the late third trimester is associated with neonatal kernicterus. Educational objective: Pregnant patients with clinically suspected acute cystitis require empiric antibiotics with nitrofurantoin, cephalexin, or amoxicillin-clavulanate for 3-7 days. Fluoroquinolones and tetracyclines are contraindicated in pregnancy, and trimethoprim-sulfamethoxazole should be avoided in the first and third trimesters. References: Urinary tract infection and bacteriuria in pregnancy. (http://www.ncbi.nlm.nih.gov/pubmed/26475951) Asymptomatic bacteriuria and symptomatic urinary tract infections in pregnancy. (http://www.ncbi.nlm.nih.gov/pubmed/18826482)

Question 8

A 26-year-old man comes to the office after learning that one of his sexual partners tested positive for HIV.  The patient has had intermittent headaches, malaise, nausea, and blurry vision over the last several weeks.  He has had no fever, sore throat, skin rash, genital lesions, or weight loss.  The patient has no prior history of sexually transmitted infections or chronic medical problems.  He smokes a pack of cigarettes daily, consumes alcohol occasionally, and does not use illicit drugs.  The patient has had multiple sexual partners over the last several years and does not use condoms consistently.  Temperature is 37.1 C (98.8 F), blood pressure is 122/74 mm Hg, and pulse is 72/min.  There is no scleral icterus, oropharyngeal lesions, or skin rash.  Mild, generalized lymphadenopathy is present.  Cardiopulmonary and abdominal examinations are normal.  Cranial nerves, deep tendon reflexes, and sensation are normal.  No nuchal rigidity is present.  Ophthalmologic examination reveals no abnormalities.  Screening HIV immunoassay is positive.  Other laboratory studies are as follows:  A subsequent fluorescent treponemal antibody absorption test is positive.  Contrast-enhanced CT scan of the head reveals no space-occupying lesions.  Which of the following is the most appropriate next step in management of this patient's treponemal infection?

Accepted Answer

Explanation: This patient with HIV has positive 2-step serology for syphilis, a sexually transmitted infection caused by the spirochete Treponema pallidum. Hematogenous dissemination of the spirochete occurs early in the disease course and frequently leads to seeding of the cerebrospinal fluid (CSF). Although this nervous system infection is usually asymptomatic at first and may clear spontaneously, any patient with syphilis who has neurologic symptoms (eg, headache, blurred vision) requires a lumbar puncture to evaluate for neurosyphilis. Patients with HIV are at greatest risk for developing neurosyphilis, particularly when CD4 counts are <350/mm³ and rapid plasma reagin titers are >1:128. Diagnosis is typically confirmed when CSF analysis reveals an elevated leukocyte count (>5/mm³) and positive VDRL or fluorescent treponemal antibody absorption (FTA-ABS) testing. (Choice A) Patients who do not have neurologic symptoms do not require additional testing and can proceed with treatment based on the stage of illness. This patient has neurologic symptoms and requires lumbar puncture prior to treatment (as the treatment for neurosyphilis is different from that for other stages of illness). (Choices B, C, and E) False positive nontreponemal testing (eg, rapid plasma reagin) can occur in patients with HIV but is usually low titer (<1:16) and associated with negative treponemal testing (eg, FTA-ABS). This patient with high titer nontreponemal testing and a positive treponemal test has syphilis. He does not require additional treponemal testing with T pallidum enzyme immunoassay or repeat serology. Lumbar puncture and appropriate treatment are now required and should not be delayed due to risk of progression and spread to others. Educational objective: Patients with syphilis who have neurologic signs or symptoms require a lumbar puncture to evaluate for neurosyphilis prior to consideration of treatment. References: Occurrence, risk factors, diagnosis and treatment of syphilis in the prospective observational Swiss HIV Cohort Study. (http://www.ncbi.nlm.nih.gov/pubmed/20616699) Neurosyphilis in the age of AIDS: clinical and laboratory features. (http://www.ncbi.nlm.nih.gov/pubmed/19768370)

Question 9

A 25-year-old man comes to the employee health center for a physical examination prior to starting work as a patient care technician in a community hospital.  The patient's family immigrated to the United States from Eastern Europe when he was a toddler.  He received a medical evaluation prior to immigrating, but the records are not available.  The patient has had no fevers, chills, night sweats, weight loss, cough, or fatigue.  He has no chronic medical problems and takes no medications.  He consumes alcohol occasionally but does not use tobacco or illicit drugs.  The patient went on a 2-month backpacking trip through Central and South America a year ago.  His immunization records are up to date.  He has a small scar in the right deltoid area and notes that he received a bacillus Calmette-Guérin vaccination as an infant.  The patient has no other abnormalities on physical examination. The patient's interferon-gamma release assay (IGRA) is positive.  He is asymptomatic and feels well.  Chest x-ray reveals no abnormalities.  Which of the following is the next most appropriate step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bfc9_650e_8f63_afc5104364eb_MD0005_00 Health care providers with positive tuberculosis (TB) screening require further evaluation with chest x-ray and symptom review to determine if they have latent or active disease. Findings concerning for active TB include the following: Nonspecific symptoms - unexplained weight loss, anorexia, night sweats, fever, fatigue Pulmonary symptoms - coughing >3 weeks, hemoptysis, chest pain Chest x-ray findings - cavitation or infiltrate Patients with no symptoms or x-ray abnormalities have latent tuberculosis infection (LTBI). Although LTBI is considered noninfectious, individuals with LTBI are at risk for conversion to active disease. If conversion occurs, TB can spread from one individual to another. Health care providers with LTBI are generally given treatment with isoniazid daily for 9 months. (Choices A and E) Patients with a positive interferon-gamma release assay (IGRA) or tuberculin skin test (TST) do not require additional confirmation of TB exposure with repeat TST or IGRA. (Choices B and D) Individuals with active TB require microbial diagnosis with serial sputum samples for acid-fast bacilli and mycobacterial culture. Once a microbial diagnosis is obtained, treatment with 4-drug therapy is typically initiated. This patient with no symptoms and a normal chest x-ray has LTBI, not active TB. Treatment with isoniazid daily should be initiated without additional testing. Educational objective: Health care providers with positive tuberculosis screening should receive chest x-ray and symptom review to determine if they have latent or active disease. Those with no symptoms or chest x-ray abnormalities (eg, infiltrate, cavitation) are considered to have latent tuberculosis infection and should be offered treatment with isoniazid daily for 9 months.

Question 10

A 19-year-old man comes to the student health center due to 2 days of burning pain during urination.  He has also had itching of the urethral meatus but no urinary discharge, fever, chills, or rash.  The patient has no chronic medical conditions and takes no medications.  He had unprotected sexual intercourse with a new female partner a week ago.  The patient has smoked a pack of cigarettes daily since age 14.  He drinks alcohol on weekends and does not use illicit drugs.  Vital signs are within normal limits.  There is scant, watery urethral discharge at the urethral meatus.  There are no genital ulcers, rashes, erythema, or inguinal lymphadenopathy.  Urethral swab is performed, and Gram stain of the urethral fluid reveals many neutrophils but no organisms.  Nucleic acid amplification tests of the urine are sent for Chlamydia trachomatis and Neisseria gonorrhoeae. The patient received treatment with a single dose of azithromycin but returns to the office 2 weeks later due to continued burning with urination.  Since his previous visit, he has had no urethral discharge, fever, chills, scrotal pain, rash, or additional sexual encounters.  Nucleic acid amplification testing from his prior visit was negative for Neisseria gonorrhoeae and Chlamydia trachomatis.  Screening for syphilis with rapid plasma reagin and for HIV with fourth-generation HIV testing was also negative.  No urethral discharge is present, and the remainder of the physical examination is normal.  Which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Patients with urethritis often have continued symptoms after initial treatment. This can be due to reinfection, medication noncompliance, or infection with an organism not sensitive to initial empiric treatment. The first diagnostic step is repeating the urethral fluid Gram stain to confirm ongoing urethritis (≥2 leukocytes/hpf). If positive, patients should undergo nucleic acid amplification (NAAT) testing of the urine for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis (if available). This patient has continued symptoms of nongonococcal urethritis (NGU) after treatment with azithromycin, no new sexual activity, and negative testing for C trachomatis and N gonorrhoeae, suggesting an infection with an azithromycin-insensitive organism. Most cases of NGU not effectively treated with azithromycin are due to C trachomatis resistance or M genitalium or T vaginalisinfection. Persistent C trachomatis is usually treated with doxycycline, M genitalium is treated with moxifloxacin, and T vaginalis is treated with metronidazole. (Choice A) Fluorescent treponemal antibody absorption testing can be used for syphilis screening. This patient with a negative rapid plasma reagin test and no symptoms of primary syphilis (eg, chancre, lymphadenopathy) does not need a second syphilis screening test. (Choice B) Genital herpes simplex virus infection can be confirmed by PCR, viral culture, or serologic testing. Genital herpes is typically associated with multiple vesicles on an erythematous base, not isolated dysuria and urethral discharge. (Choice D) A 6-week course of trimethoprim-sulfamethoxazole can be used to treat bacterial prostatitis. Chronic bacterial prostatitis usually causes >3 months of urinary tract symptoms (frequency, dysuria, urgency) and/or pain in the perineum. Acute bacterial prostatitis usually causes fevers, chills, cloudy urine, and voiding symptoms. This young, sexually active patient has had dysuria for a few weeks and scant urethral discharge. Urethritis is more likely; a diagnosis of chronic prostatitis would be premature. (Choice E) Ceftriaxone is the antibiotic of choice for gonococcal urethritis. This patient had negative testing for N gonorrhoeae, making gonococcal urethritis unlikely. Educational objective: Patients with nongonococcal urethritis frequently have continued symptoms after azithromycin therapy due to reinfection, resistance, or infection with an organism (eg, Mycoplasma genitalium) not susceptible to azithromycin. Patients should receive repeat urethral Gram stain and nucleic acid amplification testing of the urine for common urethritis organisms to identify the best next treatment.

Question 11

A 25-year-old man is brought to the emergency department due to high-grade fever, chills, myalgias, and skin rash, which started on the day of admission. He also had nausea and 3 episodes of profuse watery diarrhea and is now feeling lightheaded. Two days ago, he underwent corrective surgery for a deviated nasal septum but otherwise has no other past medical history. The patient has not traveled recently and has not been around sick contacts. He does not use illicit drugs. His temperature is 39.4 C (103 F), blood pressure is 85/50 mm Hg, and pulse is 116/min. Oxygen saturation is 98% on room air. He is lethargic but has no focal weakness or nuchal rigidity. Examination shows clear lung fields and tachycardia with normal first and second heart sounds. The abdomen is soft and nontender. There is nasal packing in both nostrils. Skin examination shows a diffuse, red, macular rash that also involves the palms and soles. Blood cultures are sent. Item 1 of 2 Which of the following is the most likely cause of this patient's symptoms?

Accepted Answer

Explanation: The patient's clinical scenario and history of nasal packing are suggestive of toxic shock syndrome (TSS). Most patients with TSS have a prodrome of fever, chills, and myalgias that evolves into a multisystemic syndrome (eg, hypotension and shock with dermatologic, gastrointestinal, muscular, renal, and/or neurologic findings); some patients can become abruptly ill within hours. Almost all menstrual and most non-menstrual cases of TSS are due to Staphylococcus aureus and are usually associated with a staphylococcal exotoxin called TSS toxin-1. The pathophysiology involves widespread activation of T cells by exotoxins acting as superantigens (ie, can activate T cells directly without needing to be processed by antigen recognition cells). Massive cytokine production and release occur, leading to the observed clinical manifestations. (Choice B) Bacterial overgrowth and dissemination are characteristic of bacterial endocarditis. (Choices C and D) TSS is not considered an allergic or hypersensitivity reaction. (Choice E) TSS is primarily due to exotoxin effects (although contributions from endotoxins are also possible), not massive bacterial lysis and circulating endotoxin (which would be the main mechanism of septic shock). Educational objective: The pathophysiology of toxic shock syndrome involves widespread activation of T cells by exotoxins acting as superantigens, leading to the massive release of cytokines.

Question 12

A 4-year-old girl is brought to the emergency department due to fever and lethargy.  Her parents say she has been withdrawn and less playful over the last 2 weeks.  She has also had several days of low-grade fever and headaches.  Since yesterday morning, the patient has mostly slept and seems to be increasingly confused.  She has no significant prior medical problems and is up to date with recommended vaccinations.  Her grandfather, who is visiting the family from South Asia, is being evaluated for cough; otherwise, the patient has no sick contacts.  The family has a pet cat.  Temperature is 38 C (100.4 F).  The patient is somnolent and responds to painful stimuli.  There is resistance to passive neck flexion.  Her right eye is deviated medially, and funduscopic examination reveals several ill-defined, raised, yellow-white nodules near the bilateral optic discs.  CT scan of the head reveals basilar meningeal enhancement.  Lumbar puncture is performed, and cerebrospinal fluid analysis results are as follows:  The patient's cerebrospinal fluid samples are sent for acid-fast bacilli staining and culture.  The parents note that the patient's grandfather also tested positive for sputum acid-fast bacilli.  Which of the following is most accurate about the management of this child?

Accepted Answer

Explanation: This patient with acid-fast bacilli in her cerebrospinal fluid (CSF) has tuberculous meningitis. Prolonged treatment is required with 2 months of 4-drug therapy (isoniazid, rifampin, pyrazinamide, and either a fluoroquinolone or injectable aminoglycoside), followed by 9-12 months of continuation therapy (isoniazid plus rifampin) (Choice E). As antitubercular treatment can result in a transient worsening of central nervous system inflammation, patients with tuberculous meningitis are typically given 8 weeks of adjuvant glucocorticoid therapy (dexamethasone or prednisone). This significantly reduces morbidity and mortality. (Choice B) Patients should be initiated on antitubercular treatment and glucocorticoids as soon as tuberculous meningitis is strongly suspected (eg, basilar enhancement, characteristic CSF findings). Delaying for bacterial confirmation, which often takes several days, increases the risk of morbidity. (Choice C) Isoniazid, rifampin, and pyrazinamide are all bactericidal with good CSF penetration; intrathecal medications are not required. (Choice D) Tuberculous meningitis is associated with a high risk of long-term neurologic sequelae. Prompt treatment reduces this risk, but many patients have permanent neurologic damage. Educational objective: Patients with suspected tuberculous meningitis should be initiated on treatment prior to bacteriologic confirmation. Treatment involves 2 months of 4-drug therapy with isoniazid, rifampin, pyrazinamide, and either a fluoroquinolone or injectable aminoglycoside, followed by 9-12 months of continuation therapy with isoniazid plus rifampin. Patients should also receive adjuvant glucocorticoids to reduce treatment-associated central nervous system inflammation.

Question 13

A 25-year-old woman comes to the office due to 4 days of burning with urination, increased urinary frequency, and blood in her urine. The patient has not had fevers, chills, or abnormal vaginal discharge. She has tried to treat her symptoms with cranberry juice and increased fluid intake but has had no improvement. The patient has been in a monogamous relationship for the last 8 months. She and her partner have intercourse 3 or 4 times a week; they use a progestin subdermal implant and condoms with spermicide for contraception. The patient voids immediately after intercourse but has had 3 urinary tract infections in the last 7 months. She has no chronic medical conditions but had a laparoscopic ovarian cystectomy for a mature teratoma at age 20. The patient takes a multivitamin daily. She drinks wine on special occasions but does not use tobacco or illicit drugs. Temperature is 36.7 C (98 F), blood pressure is 110/60 mm Hg, and pulse is 58/min. BMI is 22 kg/m². Abdominal examination shows suprapubic tenderness but no costovertebral angle tenderness. Pelvic examination reveals a small, nontender uterus with no adnexal masses. Speculum examination reveals a normal cervix with no abnormal discharge. Urinalysis results are as follows: A 1-week course of antibiotics is prescribed. In addition to the course of antibiotics, which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bfca_7681_8f63_c9b361f654eb_MD0005_00 This patient has recurrent urinary tract infections (UTI), defined as >2 infections in 6 months or >3 infections in 1 year. Risk factors for recurrent UTI include a history of cystitis at age <15 years, spermicide use, recent new sexual partner, and postmenopausal status. Behavioral strategies that may help decrease the risk of UTI recurrence include early postcoital voiding, adequate oral hydration, and avoidance of spermicides (Choice A). However, the most effective treatment for recurrent cystitis is antibiotic prophylaxis. Patients with development of a UTI temporally related to intercourse can use postcoital antibiotic prophylaxis. Patients with recurrent UTIs unrelated to sexual activity are managed with daily low-dose antibiotic suppression. Typical antibiotics used for prophylaxis include trimethoprim-sulfamethoxazole, nitrofurantoin, cephalexin, and ciprofloxacin.(Choice B) A renal ultrasound is indicated for patients with recurrent UTIs that do not respond to antibiotics, particularly when there is concern for an underlying etiology such as nephrolithiasis or obstructive uropathy. (Choice C) Acute cystitis is a common cause of hematuria. To rule out malignancy, cystoscopy and bladder biopsy are indicated in patients with hematuria that does not resolve with antibiotic therapy. (Choice D) Urodynamic testing and measurement of postvoid residual volume are indicated in the evaluation of urinary incontinence. This patient has no urinary incontinence; therefore, these tests are not indicated. Educational objectives: Recurrent urinary tract infections refer to >2 infections in 6 months or >3 infections in 1 year. Management of recurrent urinary tract infections is with antibiotic prophylaxis. References: Urinary tract infections: current and emerging management strategies. (http://www.ncbi.nlm.nih.gov/pubmed/23645845)

Question 14

A 28-year-old primigravid woman comes to the office for her first prenatal visit.  She is 9 weeks pregnant by date of her last menstrual period.  The patient reports excessive tiredness, intermittent nausea, and anorexia.  She has also had subjective fever, night sweats, and dry cough.  The patient has no prior medical problems and takes a prenatal multivitamin daily.  She does not use tobacco, alcohol, or illicit drugs.  The patient's mother recently came to visit her from Southeast Asia but had to return back early after becoming sick.  Temperature is 38 C (100.4 F), blood pressure is 120/80 mm Hg, and pulse is 76/min.  Sclerae are anicteric and mucous membranes are pink and moist.  Heart sounds are normal with no murmurs.  Fine crackles are present over the right posterior thorax.  The abdomen is soft and nontender with no hepatosplenomegaly.  Pelvic examination reveals an appropriately enlarged uterus.  Chest radiograph reveals a right upper lobe infiltrate with a small cavity.  Two of three sputum samples are positive for acid-fast bacilli.  Liver function studies are within normal limits and testing for HIV, hepatitis B virus, and hepatitis C virus are negative.  Which of the following is the most appropriate next step in management of this patient's pulmonary infection?

Accepted Answer

Explanation: This pregnant patient has an upper lobe cavitary infiltrate and acid-fast bacilli in her sputum, suggesting active pulmonary tuberculosis (TB). Pregnant women with active TB require treatment as untreated infections carry significant risk for the mother, fetus, and close contacts. Treatment usually involves 3-drug therapy with isoniazid (INH), rifampin (RIF), and ethambutol for 2 months followed by INH and RIF for 7 additional months. All 3 of these medications cross the placenta but are not associated with significant fetal toxicity. Pyrazinamide, part of the 4-drug TB treatment given to most nonpregnant individuals, is generally not administered to pregnant patients due to uncertain teratogenic properties and little contribution to overall TB treatment efficacy. Pregnant women undergoing treatment for TB should also receive pyridoxine (vitamin B₆) supplementation to prevent INH-induced neurotoxicity. Counseling about medication side effects and monthly monitoring for disease response and drug-associated hepatitis are required. ₆ (Choice A) The benefits of treatment outweigh the risk in pregnant patients with active TB. Those with latent TB (positive tuberculin skin test with no symptoms or chest x-ray abnormalities) generally do not require treatment until after delivery. (Choice B) Active TB rarely causes a placental infection but may result in a low birth weight infant. Treatment is effective, and pregnancy termination is not indicated. (Choice C) Ethambutol is given in addition to INH, RIF, and pyridoxine for the first 2 months of therapy. (Choice D) INH monotherapy is often used to treat latent (not active) TB. This patient with active TB requires multidrug therapy. Educational objective: Pregnant women who develop active tuberculosis require treatment with multidrug therapy and pyridoxine. Treatment usually involves 3-drug therapy with isoniazid (INH), rifampin (RIF), and ethambutol for 2 months followed by INH and RIF for 7 additional months.

Question 15

A 48-year-old man comes to the emergency department with several days of headache, photophobia, nausea, and vomiting.  He has also had decreased hearing in the left ear and occasional vision floaters for the past week.  The patient has no earache, tinnitus, or vertigo.  He was treated for gonorrhea 6 months ago with a single antibiotic injection.  He uses intravenous drugs and reports having unprotected sex with multiple partners.  The patient does not use tobacco or alcohol and has not traveled recently.  His temperature is 37.2 C (99 F), blood pressure is 122/68 mm Hg, and pulse is 92/min.  He has bilateral eye irritation and a generalized maculopapular rash, as shown in the exhibit.  Multiple, nontender cervical and inguinal lymph nodes are palpable.  There is sensorineural hearing loss in the left ear and neck stiffness.  Cardiopulmonary examination is normal.  The abdomen is soft and nontender.  The motor examination is symmetric, and reflexes are 2+ bilaterally throughout the upper and lower extremities.  Which of the following is the most likely diagnosis?

Accepted Answer

Explanation: 11ec2b69_bfc4_8302_8f63_d711399a7bb9_MD0005_00 This patient with high-risk sexual behavior (unprotected sex with multiple partners, history of gonorrhea) has signs and symptoms of meningitis (headache, photophobia, neck stiffness) that have developed subacutely and are accompanied by floaters, eye irritation, and hearing loss. These features are suggestive of symptomatic meningitis, ocular syphilis, and otosyphilis and are likely manifestations of early neurosyphilis, which occurs most commonly during the secondary stage of syphilis (as indicated by the generalized maculopapular rash and lymphadenopathy). Neurosyphilis can occur at any time following Treponema pallidum infection. The early stages usually affect the cerebrospinal fluid (CSF), meninges, and vasculature and are not considered manifestations of tertiary syphilis; the late forms more commonly cause disease of the spinal cord (eg, tabes dorsalis) and brain parenchyma and are considered manifestations of tertiary syphilis. Patients with syphilitic meningitis are usually not as sick as those with bacterial meningitis and frequently have a prodrome several days prior to meningitic symptoms. A CSF-VDRL test is almost universally reactive. Ocular syphilis can present as impaired vision with posterior uveitis, retinitis, or optic neuritis. Cranial neuropathies, especially of the optic, facial, or auditory nerves, can occur. Otosyphilis may also present with tinnitus. (Choices A and C) Both acute HIV infection and infectious mononucleosis can present with fever, lymphadenopathy, rash, and neurologic symptoms. However, cranial nerve palsies and visual and auditory symptoms are not typical of acute HIV. Neurologic symptoms of mononucleosis (eg, meningitis, cranial neuropathies) are rare and usually develop 2-4 weeks after other acute symptoms. (Choice B) Disseminated gonococcemia presents as either a combination of rash with tenosynovitis and non-purulent polyarthralgia or lone purulent polyarthritis. (Choice D) Meningococcal infections may present with rash and meningitis but would progress rapidly (usually over a period of hours rather than days) to severe and life-threatening meningitis. Educational objective: Early neurosyphilis may present with symptomatic meningitis, ocular syphilis, and otosyphilis. Patients with syphilitic meningitis are usually not as sick as those with bacterial meningitis and frequently have a prodrome several days preceding presentation of meningitic symptoms. Cranial neuropathies, especially of the optic, facial, or auditory nerves, can occur. References: Canadian Public Health Laboratory Network laboratory guidelines for the diagnosis of neurosyphilis in Canada. (http://www.ncbi.nlm.nih.gov/pubmed/25798161) Neurosyphilis in the modern era. (http://www.ncbi.nlm.nih.gov/pubmed/15548491)

Question 16

A 25-year-old man is brought to the emergency department due to high-grade fever, chills, myalgias, and skin rash, which started on the day of admission.  He also had nausea and 3 episodes of profuse watery diarrhea and is now feeling lightheaded.  Two days ago, he underwent corrective surgery for a deviated nasal septum but otherwise has no other past medical history.  The patient has not traveled recently and has not been around sick contacts.  He does not use illicit drugs.  His temperature is 39.4 C (103 F), blood pressure is 85/50 mm Hg, and pulse is 116/min.  Oxygen saturation is 98% on room air.  He is lethargic but has no focal weakness or nuchal rigidity.  Examination shows clear lung fields and tachycardia with normal first and second heart sounds.  The abdomen is soft and nontender.  There is nasal packing in both nostrils.  Skin examination shows a diffuse, red, macular rash that also involves the palms and soles.  Blood cultures are sent. Which of the following is the most important next step in the treatment of this patient?

Accepted Answer

Explanation: Patients with symptoms suggestive of toxic shock syndrome (TSS) should be carefully examined for any potentially associated foreign bodies (eg, nasal packing), which should be removed. They may require extensive fluid replacement, which can reach 20 L per day. Physicians generally administer clindamycin (which theoretically prevents toxin synthesis) with or without antistaphylococcal antimicrobial therapy (vancomycin, or oxacillin or nafcillin if susceptible) to eradicate the organism and prevent TSS recurrence. Corticosteroids do not seem to affect mortality and are not routinely recommended (Choice D). (Choice A) If hypotension persists despite fluid resuscitation, vasopressors agents may also be needed in the intensive care unit; dobutamine is usually reserved for cardiogenic shock. (Choice B) Epinephrine and antihistamines are used in the management of allergic reactions leading to anaphylactic shock. Antihistamines are not likely to help with TSS. (Choice E) Polyclonal human immunoglobulin has not been extensively assessed for the treatment of TSS and appears to be more effective in streptococcal rather than staphylococcal TSS. It can be considered in severe cases (eg, patients unresponsive to fluids and pressors). Educational objective: The mainstay of treatment for toxic shock syndrome is supportive therapy. Patients may require extensive fluid replacement that can reach 20 L per day.

Question 17

A 26-year-old man comes to the office after learning that one of his sexual partners tested positive for HIV.  The patient has had intermittent headaches, malaise, nausea, and blurry vision over the last several weeks.  He has had no fever, sore throat, skin rash, genital lesions, or weight loss.  The patient has no prior history of sexually transmitted infections or chronic medical problems.  He smokes a pack of cigarettes daily, consumes alcohol occasionally, and does not use illicit drugs.  The patient has had multiple sexual partners over the last several years and does not use condoms consistently.  Temperature is 37.1 C (98.8 F), blood pressure is 122/74 mm Hg, and pulse is 72/min.  There is no scleral icterus, oropharyngeal lesions, or skin rash.  Mild, generalized lymphadenopathy is present.  Cardiopulmonary and abdominal examinations are normal.  Cranial nerves, deep tendon reflexes, and sensation are normal.  No nuchal rigidity is present.  Ophthalmologic examination reveals no abnormalities.  Screening HIV immunoassay is positive.  Other laboratory studies are as follows:  A subsequent fluorescent treponemal antibody absorption test is positive.  Contrast-enhanced CT scan of the head reveals no space-occupying lesions. Several hours after the appropriate treatment for the syphilis is administered, the patient develops a fever and headache and feels "achy all over."  On repeat evaluation, temperature is 38.1 C (100.6 F), blood pressure is 130/82 mm Hg, and pulse is 105/min.  The remainder of the physical examination is unchanged.  Which of the following could have prevented this patient's current condition?

Accepted Answer

Explanation: Patients who develop an acute febrile syndrome within 24 hours of initial treatment for a spirochetal infection (eg, syphilis, leptospirosis, tick-borne spirochetes) usually have the Jarisch-Herxheimer reaction. This reaction is thought to be due to the rapid lysis of spirochetes, which releases bacterial proteins into the bloodstream and triggers an innate immunologic response. Manifestations commonly include fever, malaise, chills, headache, and myalgias. Although there is no effective prevention for the Jarisch-Herxheimer reaction, symptoms are generally self-limited and resolve within 48 hours. Most patients require no treatment, but those with severe manifestations can be treated with an antipyretic medication (eg, acetaminophen). (Choices A and B) The Jarisch-Herxheimer reaction is not due to an allergic reaction or interaction with other medications. Serum sickness-like reactions following initiation of beta-lactam therapy can occur, but typically not within the first 24 hours. (Choices D and E) The Jarisch-Herxheimer reaction is not mediated by mast cells or basophils so antihistamine therapy is ineffective. Corticosteroids have also not been shown to prevent or improve symptoms. Educational objective: The Jarisch-Herxheimer reaction is an acute febrile response that often occurs after the initial treatment of spirochetal illnesses such as syphilis. No effective prevention is available, but manifestations are generally self-limited and resolve within 48 hours. References: Jarisch-Herxheimer reaction after penicillin therapy among patients with syphilis in the era of the HIV infection epidemic: incidence and risk factors. (http://www.ncbi.nlm.nih.gov/pubmed/20825309) Penicillin-induced Jarisch-Herxheimer reaction. (http://www.ncbi.nlm.nih.gov/pubmed/16288069)

Question 18

A 52-year-old man comes to the office for a follow-up visit.  He had a pre-employment tuberculin skin test done 3 days ago, and had a skin reaction with 16 mm of induration.  He has not had any cough, fever, weight loss, night sweats, or recent exposure to patients with tuberculosis.  He has a 40-pack-year history of smoking and continues to smoke heavily.  He immigrated from South Korea to the United States about 8 years ago.  He had BCG vaccination as a child but never had a tuberculin skin test done in the past.  A chest x-ray is ordered and shows right upper lobe fibrosis without signs of active tuberculosis.  Which of the following is the most appropriate next step in the management of this patient?

Accepted Answer

Explanation: 11ec2b69_bfc6_30b7_8f63_f979ce81e690_MD0005_00 Given that this patient was born in South Korea, which has a relatively high incidence of tuberculosis, a 10 mm of induration cutoff for the tuberculin skin test would be most appropriate. This patient's 16 mm area of induration would therefore count as a positive test. A confounding factor in this case is the patient's prior BCG vaccination. Induration from BCG rarely exceeds 15 mm, and significantly decreases 15 years after it is received. Interferon gamma release assays can be used to distinguish a true positive tuberculin skin test from prior BCG vaccination. A chest x-ray is also a reasonable step to differentiate the 2 entities, with this patient's upper lobe fibrosis strongly suggestive of latent tuberculosis. While there are no radiographic signs of active infection in this patient, the presence of active tuberculosis cannot be entirely excluded radiographically and correlation with the patient's symptoms is needed. Ancillary tests such as sputum culture may be needed before determining that the patient has no active tuberculosis. Given the radiographic findings and absence of clinical symptoms in this patient, latent tuberculosis is most likely. Treatment is still indicated for latent tuberculosis since the infection can become reactivated should the patient become immunocompromised. Several rifamycin-based regimens taken for 3-4 months (eg, daily rifampin for 4 months; daily isoniazid and rifampin for 3 months) are recommended unless there are contraindications (eg, drug-drug interactions). Longer courses are not necessary and may increase risk of hepatotoxicity (Choices D and E). (Choice A) This patient needs treatment for his latent tuberculosis otherwise he may develop reactivation should he become immunocompromised. (Choice B) Given that the patient has no evidence of active infection it is unlikely that the chest x-ray will change in a month. If there is concern for active infection then the patient's sputum should be cultured for acid fast bacilli. Educational objective: Prior BCG vaccination should rarely cause more than 15 mm induration with tuberculin skin testing. The effect of BCG vaccination on induration decreases significantly 15 years after the vaccine is received. Rifamycin-based treatment regimens for 3-4 months are recommended for patients with latent tuberculosis. References: A meta-analysis of the effect of Bacille Calmette Guérin vaccination on tuberculin skin test measurements. (http://www.ncbi.nlm.nih.gov/pubmed/12200526) Identification and management of latent tuberculosis infection. (http://www.ncbi.nlm.nih.gov/pubmed/19496388)

Question 19

A 24-year-old woman, gravida 1 para 0, comes to the office at 12 weeks gestation for an initial prenatal visit. She is feeling well and reports no nausea, cramping, or vaginal bleeding. The patient has no chronic medical conditions and has had no previous surgeries. She takes a prenatal vitamin daily. Pap test and sexually transmitted infection screening last year were normal. Family history is not significant. She drank 1 or 2 alcoholic beverages a week prior to pregnancy, but does not use tobacco or illicit drugs. The patient developed a skin rash and difficulty breathing after taking penicillin for streptococcal pharyngitis as a child. Blood pressure is 110/60 mm Hg and pulse is 78/min. BMI is 26 kg/m². Bimanual examination is consistent with a 12-week-sized uterus. Pelvic ultrasound reveals a singleton intrauterine pregnancy consistent with gestational age. Fetal heart rate is 160/min. Laboratory results from this visit are as follows: Which of the following is the most appropriate treatment for this patient?

Accepted Answer

Explanation: 11ec2b69_bfc2_601a_8f63_2bb2a9dd562f_MD0005_00 Treponema pallidum crosses the placenta; a syphilis infection during pregnancy can result in vertical transmission, leading to adverse fetal outcomes including fetal growth restriction, intrauterine fetal demise, and congenital syphilis (eg, hepatomegaly, jaundice, rash, skeletal abnormalities). Therefore, all pregnant patients are screened at the initial prenatal visit with either the rapid plasma reagin or the VDRL test. Repeat screening can be performed in the early third trimester for high-risk patients. Those with a positive screening test require confirmatory testing with a treponemal-specific test (eg, fluorescent treponemal antibody absorption, microhemagglutination test for antibodies to T pallidum). Penicillin is the first-line therapy for the treatment of syphilis during pregnancy as it treats maternal disease, prevents vertical transmission, and treats fetal infection. Patients who have a penicillin allergy require penicillin desensitization prior to treatment. Penicillin desensitization typically involves incremental doses of either oral or intravenous penicillin followed by treatment with intramuscular penicillin G benzathine. To ensure an adequate response following treatment completion, repeat serologic titers are obtained in the third trimester (eg, 28-32 weeks gestation) and at delivery. A 4-fold or greater decrease in the serologic titer indicates treatment success; an inadequate response requires additional treatment. (Choices A and D) Azithromycin and erythromycin are second-line antibiotics for syphilis in nonpregnant patients. Although both are safe in pregnancy, neither crosses the placenta or treats fetal infection. (Choice B) Ceftriaxone is a second-line antibiotic for nonpregnant patients with syphilis. However, it is insufficiently studied for the treatment of syphilis during pregnancy. (Choice C) Doxycycline is a second-line antibiotic for nonpregnant patients with syphilis. It is contraindicated in pregnancy due to a risk of fetal tooth staining and abnormal fetal long bone development. Educational objective: Penicillin is the first-line antibiotic for patients with syphilis during pregnancy. Patients with a penicillin allergy require penicillin desensitization prior to initiating treatment. References: Syphilis during pregnancy: a preventable threat to maternal-fetal health. (http://www.ncbi.nlm.nih.gov/pubmed/27956203) The continuing threat of syphilis in pregnancy. (http://www.ncbi.nlm.nih.gov/pubmed/26871538)

Question 20

A 25-year-old man comes to the employee health center for a physical examination prior to starting work as a patient care technician in a community hospital. The patient's family immigrated to the United States from Eastern Europe when he was a toddler. He received a medical evaluation prior to immigrating, but the records are not available. The patient has had no fevers, chills, night sweats, weight loss, cough, or fatigue. He has no chronic medical problems and takes no medications. He consumes alcohol occasionally but does not use tobacco or illicit drugs. The patient went on a 2-month backpacking trip through Central and South America a year ago. His immunization records are up to date. He has a small scar in the right deltoid area and notes that he received a bacillus Calmette-Guérin vaccination as an infant. The patient has no other abnormalities on physical examination. Item 1 of 2 Regarding pre-employment evaluation for tuberculosis, which of the following is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Health care personnel (HCP) are at risk for workplace exposure to Mycobacterium tuberculosis. Prior to beginning employment, these individuals should be screened for tuberculosis (TB) to document baseline TB status. Screening can be done with either a tuberculin skin test (TST), which requires intradermal tuberculin injection, or interferon-gamma release assay (IGRA), which requires a blood sample. Although roughly comparable in accuracy, IGRA has 3 main advantages over TST: No false positives in patients with previous bacillus Calmette-Guérin (BCG) vaccine: BCG vaccine administration can cause an initial TST reaction of up to ~20 mm; serial vaccination, practiced in some countries, can boost this response. The TST reaction generally wanes with time (eg, <10 mm 10 years after BCG vaccine administration). No need for a return visit to measure induration size: The TST reaction should be read 48-72 hours after intradermal tuberculin injection. No need for 2-step confirmation: Patients who were exposed to mycobacterial antigens remotely can have a negative result to an initial TST (due to waned immunity) but a positive result to a second, "booster" TST weeks later (due to anamnestic response following the initial TST); for HCP (and close contacts of patients with active TB), a second TST is often recommended 1-4 weeks later to confirm a negative initial test. IGRA is not subject to the "booster" phenomenon. This patient who previously received a BCG vaccine should be screened with an IGRA, not a TST (Choice D). (Choice A) Although the BCG vaccine is associated with reduced risk of active tuberculosis, protection wanes 10-15 years after vaccination. In addition, all patients who work in the health care setting require pre-employment screening for TB regardless of immunization status. (Choice B) Patients who have a history of latent TB are likely to have a positive TST and IGRA for life. As a result, these patients are typically screened for TB with a chest radiograph. (Choice E) Patients with abnormal screening tests who have symptoms (eg, chronic cough, fever, night sweats) or radiographic findings (eg, cavitation, infiltrate) concerning for active TB require microbial confirmation with sputum acid-fast bacillus samples and culture. This patient is asymptomatic and should be screened with an IGRA. Educational objective: Individuals who work in the health care setting should receive pre-employment tuberculosis (TB) screening to establish baseline TB status. Two main screening tools are used: tuberculin skin test and interferon-gamma release assay (IGRA). An IGRA should be used to screen for TB in most patients with previous bacillus Calmette-Guérin vaccine as these patients may have a false-positive tuberculin skin test.

Exam 1: Advanced Clinical Medicine