Question 1

A 32-year-old female is seen for a follow-up visit six months after undergoing total thyroidectomy and central neck dissection for medullary thyroid cancer.  Pathology results revealed that the tumor was 3 cm in diameter, and 3 of 18 dissected nodes were positive for malignancy.  The fasting serum calcitonin level before surgery was 250 ng/ml (normal < 4ng/ml).  The postoperative course was uncomplicated, and she was then started on levothyroxine 0.15 mg/d.  The repeat TSH level obtained after 8 weeks was normal.  The physical examination revealed no abnormal neck masses.  The rest of the examination is also unremarkable.  Her current calcitonin level is 120 ng/ml.  What is the next best step in the management of this patient?

Accepted Answer

Explanation: The patient has residual metastatic thyroid cancer, as suggested by the persistently elevated calcitonin levels. CT scan of the neck and chest with or without high-resolution ultrasound of the neck is recommended as the next step to look for metastatic disease. Surgical resection should be performed if a resectable lesion(s) is identified. If no lesion is identified, then an abdominal CT scan and bone scan may be required. I111 octreotide or PET scan may be helpful if CT scans are negative despite the presence of elevated calcitonin levels. (Choice C)Thallium scintiscan is nonspecific and has not been studied properly in patients with medullary thyroid cancer. (Choice B)Chest x-ray has a very low sensitivity for detecting metastatic lesions, and should not be used as a solitary investigative tool. (Choice E)Ultrasonography limited to the thyroid bed will not pick up lesion(s) in other parts of the neck. (Choice A)Medullary thyroid cancer is a malignancy of parafollicular C-cells that do not concentrate iodine; therefore, total body iodine scan is not useful in detection of metastasis of medullary thyroid cancer. Educational Objective: Elevated calcitonin levels in patients with medullary thyroid cancer following total thyroidectomy indicate metastatic disease. CT scan of the neck and chest is recommended as the next step to look for metastatic disease. Medullary thyroid cancer cells do not take-up iodine; therefore, total body iodine scan is not useful.

Question 2

A 5-year-old boy is brought to the emergency department with severe leg pain that started 6 hours earlier.  His mother says that their heating system broke last night so she "tried to keep him warm with lots of blankets."  The patient was given ibuprofen and oxycodone at home without relief of pain.  He played outside with his brother yesterday but did not experience any trauma or injury.  He has not had fever, cough, vomiting, or rash.  Medical history includes mild persistent asthma and sickle cell disease, and he has been hospitalized once for a vaso-occlusive pain episode.  Temperature is 37.2 C (99 F), blood pressure is 100/62 mm Hg, pulse is 150/min, and respirations are 20/min.  Physical examination shows a young child lying in bed in significant discomfort, crying and holding his left leg.  Mucous membranes are moist and capillary refill is <2 seconds.  The lungs are clear to auscultation, and the abdomen is soft, nontender, and nondistended without organomegaly.  The left anterior calf is markedly tender to palpation but does not have erythema, warmth, or swelling.  A peripheral intravenous line is inserted, and a complete blood count is drawn. The child is admitted to the hospital and experiences improvement of his leg pain overnight.  The next morning, however, he develops chest pain and difficulty breathing.  Temperature is 38.9 C (102 F), blood pressure is 94/62 mm Hg, pulse is 124/min, and respirations are 28/min.  The patient's pulse oximetry shows 95% on room air.  Examination reveals diminished left-sided breath sounds with mild subcostal retractions.  Hemoglobin is stable from admission at 9.5 g/dL, and a blood culture is sent.  A chest x-ray is obtained.  Which of the following is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf80_759f_8f63_b1a11092e05d_MD0005_00 Acute chest syndrome (ACS) is a potentially life-threatening pulmonary complication of sickle cell disease (SCD). The diagnosis of ACS requires the presence of a new pulmonary infiltrate on chest x-ray and >1 of the following: Fever >38.5 C (101.3 F), hypoxemia, chest pain, or respiratory distress. This patient meets diagnostic criteria for ACS based on x-ray findings, fever, chest pain, and difficulty breathing. new pulmonary infiltrate on chest x-ray Causes of ACS in children include infection, asthma exacerbation, and pulmonary infarction. Because infection is the most common cause, empiric broad-spectrum antibiotics should be started promptly. First-line therapy is a third-generation cephalosporin (eg, ceftriaxone, cefotaxime) plus a macrolide (eg, azithromycin) to cover Streptococcus pneumoniae and Mycoplasma pneumoniae, respectively. Additional management includes pain control to prevent splinting and subsequent hypoventilation and atelectasis. Judicious intravenous fluids should also be administered to prevent dehydration and further sickling. (Choice A) Blood transfusion in ACS is indicated for an oxygen saturation <92%, significant anemia, or worsening symptoms despite initial treatment. Although transfusions are often required in ACS, they are avoided in SCD unless necessary, given the risk of alloimmunization. (Choice C) Continuous positive airway pressure is a form of noninvasive ventilation that can be helpful in patients with an increasing oxygen requirement or significant respiratory distress. It is not indicated in this patient who is on room air and has only mildly increased work of breathing. (Choice D) Pulmonary embolism is a complication of ACS that can be diagnosed with CT angiography of the chest, and is more common in adults. This patient also does not have severe respiratory distress or hypoxemia. (Choice E) A tension pneumothorax presents with dyspnea, hypotension, diminished breath sounds on the affected side, and tracheal deviation toward the unaffected side. Needle thoracostomy is indicated for decompression of a tension pneumothorax but has no role in the treatment of ACS. Educational objective: Acute chest syndrome in sickle cell disease is defined by the presence of a new pulmonary infiltrate on chest x-ray and fever, hypoxemia, chest pain, tachypnea, or increased work of breathing. Initial treatment includes a third-generation cephalosporin (eg, ceftriaxone) and macrolide (eg, azithromycin), pain control, and intravenous fluids. References: Managing acute complications of sickle cell disease in pediatric patients. (http://www.ncbi.nlm.nih.gov/pubmed/27775898)

Question 3

A newborn boy is evaluated on arrival in the nursery.  He was born 3 hours ago by spontaneous vaginal delivery at 40 weeks gestation after an uncomplicated pregnancy.  Apgar scores were 9 at 1 minute and 10 at 5 minutes after birth.  His mother has no significant medical history and does not take any medications.  Temperature is 36.7 C (98 F), pulse is 124/min, and respirations are 26/min.  He is awake, alert, and active with a strong cry.  His head is normocephalic and atraumatic with an open flat anterior fontanelle.  Pupils are equal and reactive to light and accommodation, and red reflexes are present bilaterally.  The nares are patent, there is no cleft lip or palate, and the pharynx is not erythematous.  Clavicles are intact without crepitus.  S1 and S2 are normal without murmurs, and lungs are clear to auscultation bilaterally.  The abdomen is soft, nontender, and nondistended with normal bowel sounds and no organomegaly.  Femoral pulses are normal and symmetrical.  All extremities move spontaneously and there is no edema.  There are no rashes, skin lesions, or jaundice, but the complexion appears ruddy with generalized erythema.  Blood samples obtained from the heel through simple prick method reveal a hematocrit of 70%. Repeat testing revealed a hematocrit of 65%.  The patient is re-evaluated in the nursery and appears comfortable, with no tachycardia or respiratory distress.  He feeds slowly but has no emesis, and voids spontaneously after his first feed.  A decision is made to observe the child without intervention.  Approximately 12 hours later, he appears irritable and lethargic.  The infant has refused all subsequent feeds and has had decreased urine output.  Nursery staff observed an episode of apnea.  Temperature is 37.4 C (99.3 F), pulse is 170/min, and respirations are 60/min.  Physical examination shows a drowsy, hypotonic, poorly responsive newborn.  The fontanelle is open and flat.  Pupils are equal and reactive with normal red reflexes.  There is no rhinorrhea.  Oral mucosa is moist.  S1 and S2 are present without murmurs.  On pulmonary examination there are no wheezes or rales, but there are intercostal retractions.  The skin is erythematous and ruddy, and there is cyanosis of the fingertips.  There are no focal neurologic deficits.  Laboratory results from peripheral blood draw are as follows:
 The patient is transferred to the neonatal intensive care unit, and treatment with intravenous fluids and glucose is initiated.  His symptoms fail to improve, and his hematocrit after several hours is 71%.  What is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: Although the majority of newborns with polycythemia are asymptomatic, some affected patients will develop hyperviscosity, which causes complications such as hypoperfusion and tissue hypoxia. This manifests clinically in signs such as plethora, lethargy, irritability, drowsiness, poor feeding, abdominal distension, and hypotonia. Respiratory compromise may occur, resulting in apnea or cyanosis. Metabolic derangements such as hypoglycemia and hyperbilirubinemia are common laboratory abnormalities. Asymptomatic patients can be observed clinically, as the condition usually resolves within the first 24 hours of life; however, those with clinical symptoms require treatment. Initial treatment consists of hydration and correction of hypoglycemia. If first-line treatment is ineffective, an alternate management strategy is partial exchange transfusion. This procedure consists of withdrawing blood from the infant and infusing normal saline. There are risks associated with this procedure, so it is not the first-line option; however, it improves short-term symptoms of hyperviscosity and is therefore a reasonable next step if more conservative management fails. (Choices A and C) Apnea, tachypnea, retractions, and cyanosis could suggest cardiac or pulmonary pathology. However, the patient has laboratory evidence of polycythemia and his cardiopulmonary examination demonstrated clear lungs and normal heart sounds. Therefore, although chest x-ray and echocardiography might be performed later as part of a complete workup, the most important next step is to correct the underlying hematologic abnormality. (Choice B) The patient is irritable and lethargic, but he does not have any focal neurologic deficits, and CT scan would expose his developing brain to a significant amount of radiation. In addition, he has evidence of polycythemia, which is known to cause neurologic symptoms. (Choice D) Apnea, tachypnea, and hypoglycemia can be markers of neonatal sepsis. However, this patient does not have other laboratory findings suggestive of sepsis (eg, neutropenia, leukocytosis, thrombocytopenia), and he has the classical clinical picture and laboratory findings of symptomatic neonatal polycythemia, so correction of the polycythemia is a more appropriate step. Educational objective: Neonatal polycythemia is frequently asymptomatic but can be a life-threatening disease that causes apnea, hyperviscosity, hypoglycemia, hyperbilirubinemia, and respiratory compromise. Treatment consists of adequate hydration and correction of metabolic derangements (eg, hypoglycemia). Partial exchange transfusion is an option if patients fail to improve with conservative management; however, there are associated risks with the procedure. References: Management of polycythemia in neonates. (http://www.ncbi.nlm.nih.gov/pubmed/20725868)

Question 4

A 30-year-old Caucasian man with no significant past medical history presents to his primary care physician complaining of nausea, vomiting, diarrhea, abdominal cramping, and fever to 38.3C (100.9F).  The symptoms started 12 hours after the man consumed a beverage that contained pureed fruit, powdered protein, and three raw eggs.  Physical examination of the man is unremarkable.  Salmonella enteritidis is subsequently isolated from his stool culture.  What is the best means of managing this patient's care?

Accepted Answer

Explanation: Symptomatic individuals found to be infected with Salmonella enteritidis should be given replacement fluid and electrolytes, as they are at risk for becoming dehydrated. Since the gastroenteritis is usually self-limited and antibiotic use has not been shown to hasten the resolution of symptoms or improve the rate of Salmonella clearance from stool, antibiotic usage is not recommended for immunocompetent adults or children older than one year of age. Therefore, supportive therapy and observation (Choice E) would be most appropriate. Salmonella enteritidis In the United States, Salmonella enteritidis is becoming increasingly resistant to ampicillin (Choice A). Even if antibiotic therapy were indicated, ampicillin would be a poor choice. Salmonella enteritidis Preemptive therapy is warranted in patient groups at greater risk for complications. These groups include children younger than twelve months of age (with special attention paid to neonates) and immunocompromised adults. Therapy may be considered for adults at least 50 years old with known atherosclerotic disease, as they are more prone to developing bacteremia and endovascular infection. Effective antibiotics include ciprofloxacin (Choice B), trimethoprim/sulfamethoxazole (Choice C), and ceftriaxone (Choice D). Educational objective: Salmonellosis does not need to be treated with antibiotics in immunocompetent individuals age 12 months or older.

Question 5

A 4-year-old girl with sickle cell disease is brought to the emergency department with fatigue and loss of appetite.  Her parents first noticed her fatigue 3 days ago when she asked to go to sleep earlier than her bedtime.  Over the past 2 days, the patient has been drinking well but eating much less than normal.  Her father states, "She's been so tired that she wouldn't even get out of bed this morning."  She had an episode of acute chest syndrome 2 years prior that required an exchange transfusion.  The patient takes folic acid and penicillin.  Immunizations are up to date, including the annual influenza vaccine.  Temperature is 36.7 C (98 F), blood pressure is 110/65 mm Hg, pulse is 120/min, and respirations are 25/min.  Oxygen saturation is 95% on room air.  Physical examination shows a pale and tired-appearing girl.  Conjunctival pallor is present.  Respiratory, abdominal, and neurologic examinations are within normal limits.  Laboratory results are as follows:  Which of the following is the most likely diagnosis of this patient?

Accepted Answer

Explanation: 11ec2b69_bf7f_3d1d_8f63_31bf94476b0f_MD0005_00 Sickle cell disease (SCD) is characterized by abnormal hemoglobin chains that result in decreased life span of red blood cells and chronic anemia. Patients compensate for this chronic anemia with increased erythropoiesis and an elevated reticulocyte count. An aplastic crisis in SCD is characterized by sudden cessation of erythropoiesis with a very low reticulocyte count (less than <1%) and resultant acute, severe anemia. Parvovirus B19, which preferentially attacks erythroid precursors rather than other cell lines, is the most common cause of an aplastic crisis in SCD. As most children are exposed to and develop immunity against parvovirus by age 15, aplastic crises are rare after early childhood. Blood transfusions are the mainstay of treatment while erythropoiesis recovers. Aplastic crises in SCD differ from aplastic anemia, which occurs in patients without SCD and is characterized by pancytopenia. (Choice A) Acute chest syndrome typically presents with fever, chest pain, and a new pulmonary infiltrate on chest x-ray. This patient is afebrile and has no chest pain or cough. (Choice C) A hyperhemolytic crisis is a very rare complication of SCD that presents with acute, severe anemia and an increased reticulocyte count, which differentiates it from an aplastic crisis. The etiology is unknown. (Choice D) Splenic sequestration is due to pooling of red blood cells in the spleen and presents with a rapidly enlarging spleen. Laboratory findings include severe anemia and marked reticulocytosis. This patient's low reticulocyte count and normal abdominal examination make sequestration unlikely. (Choice E) SCD is the most common cause of stroke in pediatric patients and should be considered in any patient with altered mental status, new focal neurologic deficits, or headache. The absence of focal neurologic deficits and headache, combined with severe anemia, makes stroke unlikely in this patient. Educational objective: An aplastic crisis in sickle cell disease is a transient failure of erythropoiesis most commonly due to parvovirus B19. Presentation includes a sudden drop in hemoglobin and a very low reticulocyte count (<1%). References: Clinical presentations of parvovirus B19 infection. (http://www.ncbi.nlm.nih.gov/pubmed/17304869) Human parvovirus B19: general considerations and impact on patients with sickle-cell disease and thalassemia and on blood transfusions. (http://www.ncbi.nlm.nih.gov/pubmed/21585562)

Question 6

A 45-year-old Caucasian female presents to your office with abdominal discomfort and distention that is especially bothersome after meals.  She has noticed recently that she gets tired more easily.  She feels "down", but denies any sleep difficulty, crying spells and suicidal ideation.  She visited a doctor approximately one year ago due to similar complaints, and was told that the problem was psychological.  She underwent myomectomy for a large uterine fibroid 8 years ago.  She is not sexually active.  Her family history is significant for pancreatic cancer in her father and a thyroid disease in her mother.  The physical examination is significant for mild pallor of the conjunctivae.  The abdomen is somewhat distended with no palpable masses.  The laboratory values are:  After taking the appropriate initial steps, you proceed with gastric endoscopy.  Which of the following findings is more likely to be present in this patient?

Accepted Answer

Explanation: Pernicious anemia is associated with a type of gastritis called autoimmune metaplastic atrophic gastritis (AMAG). AMAG is caused by autoimmune aggression against gastric mucosa. An immune response is mainly directed against oxyntic cells and intrinsic factor. The three main components of AMAG are glandular atrophy, intestinal metaplasia and inflammation. Atrophy affects mainly the gastric body and fundus. (Choice B)Typically, little changes are observed in the gastric antrum. (Choices C and D)No erosions or ulcerations are usually observed. If present, these may indicate a high probability of malignancy. (Choice E)In advanced stages, the mucosa becomes thin and atrophic, and endoscopy may demonstrate absent gastric rugae in the body and fundus. Intestinal metaplasia replaces normal oxyntic glands; sometimes, the mucosa becomes villiform and resembles normal small intestine. Educational Objective: The three main components of AMAG (which is associated with pernicious anemia) are glandular atrophy, intestinal metaplasia and inflammation. Atrophy affects mainly the gastric body and fundus. Typically, little changes are observed in the gastric antrum. *High yield*

Question 7

A 45-year-old Caucasian female presents to your office with abdominal discomfort and distention that is especially bothersome after meals.  She has noticed recently that she gets tired more easily.  She feels "down", but denies any sleep difficulty, crying spells and suicidal ideation.  She visited a doctor approximately one year ago due to similar complaints, and was told that the problem was psychological.  She underwent myomectomy for a large uterine fibroid 8 years ago.  She is not sexually active.  Her family history is significant for pancreatic cancer in her father and a thyroid disease in her mother.  The physical examination is significant for mild pallor of the conjunctivae.  The abdomen is somewhat distended with no palpable masses.  The laboratory values are:   What is the best next step in the management of this patient?

Accepted Answer

Explanation: This patient's findings (macrocytic anemia with a normal serum folate level and severely depressed serum cobalamin level) suggest the presence of B12-deficiency anemia. Accompanying gastrointestinal symptoms may indicate pernicious anemia as the cause of the problem. Pernicious anemia is characterized by the autoimmune destruction of parietal cells. The two major implicated auto-antibodies that have been described are the anti-parietal and anti-intrinsic factor (IF) antibodies. Anti-IF antibody testing is the recommended initial test for the detection of pernicious anemia. (Choice D)Anti-IF antibody testing has 50 to 84% sensitivity and almost 100% specificity in detecting pernicious anemia; anti-parietal testing is much less specific. (Choice A)Schilling test is a classic diagnostic test of pernicious anemia that uses radio-labeled cobalamin. It is more cumbersome than antibody testing, and can be used as the second-line test if the anti-IF test is negative. (Choice B)Patients with pernicious anemia are typically achlorhydric, but measurement of gastric secretions is generally not performed because it is highly invasive and non-specific. (Choice E)Bone marrow biopsy can confirm the diagnosis of megaloblastic anemia, but is also highly invasive and non-specific for the underlying cause of the problem. Educational objective: Anti-IF antibody testing has 50 to 84% sensitivity and almost 100% specificity in detecting pernicious anemia. It is the recommended initial diagnostic test.

Question 8

A 50-year-old African American man comes to the emergency department because his left leg has been bothering him. He describes vague, diffuse left leg pain that is present both at rest and with activity. He denies any chest pain, shortness of breath, palpitations, syncope, or hemoptysis. He was discharged from the hospital one month ago after being diagnosed with and treated for a left popliteal vein thrombosis. Since his discharge from the hospital, he has been taking a stable dose of warfarin every evening, without medical followup. His blood pressure is 143/82 mmHg and his heart rate is 72/min. His oxygen saturation is 98% on room air. His BMI is 37 kg/m². There is marked swelling of the left leg. His INR (International Normalized Ratio) in the emergency room is 1.4. An ultrasound examination reveals venous thrombosis involving the common femoral vein. Which of the following is the best next step in managing this patient?

Accepted Answer

Explanation: The extent of this patient's lower extremity deep venous thrombosis (DVT) has increased since it was first diagnosed one month ago - the thrombus was previously at the level of the popliteal vein and now has spread proximally to involve the common femoral vein as well. The increased DVT size is almost certainly the cause of his left lower extremity symptoms, and the proximal propagation of the thrombosis may place him at increased risk of developing a pulmonary embolism. Inadequate anticoagulation is the likely cause of this problem, since the goal INR level for this type of patient is between 2.0 and 3.0. The reason for this patient's under-anticoagulation is unclear. While the patient does describe taking the same dose of warfarin every day, he had no followup. It may be that, for his size (BMI is 37 kg/m²), the prescribed warfarin dose was too low. Outpatient follow-up of his INR would have revealed this problem. This should not be considered a failure of anticoagulation, as the patient was never adequately anticoagulated in the first place. The patient should be admitted to begin intravenous heparin therapy and will need an increase in his warfarin dose to reach an appropriate INR level. (Choice A) While this patient is at risk of developing a pulmonary embolism, he has no symptoms to suggest this at the current time and as such there is no indication for CT angiography of the chest. (Choice B) Placement of an IVC filter should be considered if appropriate anticoagulation fails, but the propagation of this patient's DVT is secondary to under-anticoagulation. (Choice D) Checking a D-dimer level is unnecessary since the test will surely be elevated given that the patient has a known thrombosis. The patient's dose of warfarin will need to be increased, but he must be started on heparin until his INR is at a therapeutic level. (Choice E) The patient should be admitted for heparin therapy until the INR reaches a therapeutic level. Educational objective: Under-anticoagulation can lead to worsening of thrombotic disease, and such patients should be started on intravenous heparin (or subcutaneous low molecular weight heparin) until a therapeutic INR is achieved with warfarin. Such cases should not be considered anticoagulation failures that warrant placement of an IVC filter.

Question 9

In three months, his repeat hemoglobin level is 19.0 g/dL.  His oxygen saturation in the office is 95% on room air.  His carboxyhemoglobin level is normal and serum erythropoietin level is elevated.  Iron studies and serum folate and vitamin B12 levels are all normal.  Urinalysis shows no blood, no RBCs, and trace protein.  Which of the following is the best next step in managing this patient?

Accepted Answer

Explanation: This patient was appropriately evaluated with a repeat serum hemoglobin level followed by measurement of the erythropoietin level. The elevated erythropoietin level essentially eliminates polycythemia vera as a possibility. The most likely cause of this patient's polycythemia is therefore chronic hypoxia. The normal carboxyhemoglobin level excludes carbon monoxide toxicity, which can be a cause of polycythemia in patients who smoke heavily. Since this patient's oxygen saturation is 95% on room air, significant underlying pulmonary disease is unlikely. It is therefore reasonable to consider a source of intermittent hypoxia, the most common of which is sleep apnea. Nocturnal oximetry would be a reasonable test at this point since nighttime hypoxia from sleep apnea is a potential cause of reactive polycythemia. Given his high BMI, obesity hypoventilation could also be contributing his sleep apnea/hypoxia. (Choice A) Bone marrow biopsy can be used to confirm a diagnosis of polycythemia vera, but this diagnosis has been excluded by the elevated serum erythropoietin. (Choice B) Hemoglobin electrophoresis is beneficial when an abnormality in the hemoglobin molecule itself is suspected, such as in sickle cell anemia or the thalassemias. (Choice C) JAK2 mutation testing is sometimes used as a confirmatory test for polycythemia vera, which has already been excluded by the elevated serum erythropoietin. (Choice E) Phlebotomy can help reduce symptoms of polycythemia vera. However, treatment of secondary polycythemia should be directed towards the underlying cause, which has yet to be determined in this case. Educational objective: Chronic hypoxia is the most common cause of secondary polycythemia. Carboxyhemoglobin levels should be obtained to exclude carbon monoxide poisoning in certain patients, including those who smoke heavily. Sleep apnea should be considered in patients with a relatively normal oxygen saturation on physical examination, as the hypoxia may be only intermittently present at night.

Question 10

An 18-month-old boy is brought to the emergency department by his adoptive mother due to increasing irritability.  The patient has been tiring easily for the past 3-4 days; now he is irritable, constantly crying, and inconsolable.  The mother tried to comfort him by playing with his toys, but he refuses to pick them up and cries more when he attempts to walk.  The patient has had no recent trauma, fever, cough, or runny nose.  He was adopted 6 months ago from Nigeria and has been healthy.  Immunizations are up to date.  Family history is unknown.  Temperature is 37.8 C (100 F) and pulse is 120/min.  The patient is alert and appears uncomfortable.  Pupils are equal and reactive.  Scleral icterus is present and the conjunctivae are pale.  Cardiopulmonary examination is normal.  The hands and feet are mildly swollen and tender to palpation.  Hemoglobin is 9 g/dL.  Which of the following tests would establish the underlying diagnosis in this patient?

Accepted Answer

Explanation: 11ec2b69_bf7e_79cb_8f63_39b14ea7baac_MD0005_00 Sickle cell disease (SCD) is an autosomal recessive disorder caused by a hemoglobin (Hb) beta globin chain mutation. When patients are exposed to triggers (eg, cold weather, dehydration, overexertion), the red blood cells (RBCs) sickle and destroy erythrocytes. In children age <4, a common sequestration site is the small bones of the hands and feet; this sequestering results in bone infarction and a vaso-occlusive pain crisis known as dactylitis (painful swelling of the hands or feet). Because of systemic inflammation, patients often have an associated low-grade fever. RBC destruction due to intravascular hemolysis also results in chronic hemolytic anemia (eg, scleral icterus, jaundice). The gold standard for diagnosing SCD is hemoglobin electrophoresis, which shows predominant HbS with absent HbA. Acute management includes hydration and pain control; hydroxyurea can help prevent future vaso-occlusive episodes. (Choice A) A direct Coombs test is positive in autoimmune hemolytic anemia, which can be associated with systemic lupus erythematosus. Patients with lupus have joint pain; however, this patient does not fulfill diagnostic criteria (eg, malar rash, oral ulcers). (Choice B) Glucose-6-phosphate dehydrogenase deficiency typically presents shortly after exposure to an oxidative stress (eg, sulfa drugs, fava beans) with hemolysis (eg, jaundice, pallor, dark urine). Patients may have associated abdominal and/or back pain rather than joint pain. (Choice D) Parvovirus may cause anemia and arthropathy; however, the anemia is due to red cell aplasia rather than hemolysis. Arthritis is more common in adolescents/adults than in young children. (Choice E) Thick and thin smears are used to diagnose malaria, which causes anemia from hemolysis of parasitized RBCs. Cyclical high fever and malaise, headache, and abdominal pain are typical, but are not seen in this patient. Educational objective: Early manifestations of sickle cell disease include dactylitis, painful swelling of the hands or feet due to bone infarction, and hemolytic anemia. Predominant hemoglobin S with absent hemoglobin A on hemoglobin electrophoresis is diagnostic. References: Musculoskeletal manifestation of sickle cell disease: a review. (http://www.ncbi.nlm.nih.gov/pubmed/26623213) Sickle cell disease. (http://www.ncbi.nlm.nih.gov/pubmed/27637966)

Question 11

A 56-year-old Caucasian male presents to your office for a routine check-up. He complains of chronic cough, fatigue, and occasional headaches. He has longstanding hypertension, which is controlled with amlodipine and lisinopril. Three months ago, he was diagnosed with acute bronchitis and treated with a short course of antibiotics. He smokes one pack of cigarettes daily and consumes alcohol occasionally. He denies any recreational drug use. His family history is significant for prostate cancer in his father and renal cell carcinoma in his uncle. His blood pressure is 147/82 mmHg, pulse is 93/min, temperature is 36.7 C (98 F), and respirations are 14/min. His oxygen saturation is 94% on room air. His BMI is 42 kg/m². Physical examination is unremarkable. His chest X-ray is normal. Item 1 of 2 Which of the following is the best next step in managing this patient?

Accepted Answer

Explanation: The most notable abnormality in this patient's laboratory values is a markedly elevated hemoglobin/hematocrit level. This would qualify as polycythemia, which is considered when the hemoglobin level is greater than 16.5 g/dL in a woman or 18.5 g/dL in a man. Repeat testing is generally indicated to ensure that a spurious value has not been obtained. In the majority of cases, polycythemia is caused by chronic hypoxia secondary to cardiac or pulmonary disease. The presence of pulmonary disease is possible in this patient given his smoking history. The best initial test for determining the cause of polycythemia is a serum erythropoietin level. In polycythemia secondary to chronic hypoxia, a high serum erythropoietin level is expected as a compensatory mechanism to correct for the hypoxia. Erythropoietin may be inappropriately elevated in the presence of certain tumors that secrete the hormone, such as renal cell carcinoma. A low erythropoietin level would suggest polycythemia vera, a chronic myeloproliferative disorder. (Choice A)A bone marrow biopsy is unnecessarily invasive at this time, as the presence of a high erythropoietin level would essentially exclude polycythemia vera. (Choice B)Polycythemia can be caused by various neoplasms, particularly renal cell carcinoma, which could be detected with a CT of the abdomen. However, serum erythropoietin is a better first test because it helps to better characterize the cause of polycythemia and guide further diagnostic evaluation. (Choice D)Hemoglobin electrophoresis is most helpful when an abnormality is suspected in the hemoglobin molecule itself, such as in sickle cell anemia or the thalassemias. (Choice E)Serum iron and B12 levels are more helpful in the work-up of low hemoglobin. Educational Objective: Serum erythropoietin is a good initial diagnostic test for the evaluation of polycythemia and helps to guide the remainder of the work-up. A low erythropoietin level suggests polycythemia vera, whereas a high erythropoietin level suggests a secondary cause of polycythemia, such as chronic hypoxia or a hormone-producing neoplasm (commonly renal cell carcinoma).

Question 12

A 27-year-old woman, gravida 3 para 1 aborta 1, at 20 weeks gestation comes to the office as she is concerned that she might be at risk for hemolytic disease.  She just learned that her sister-in-law's second baby has hydrops fetalis due to Rh(D) incompatibility and is concerned that this could happen to her second baby as well.  The patient's pregnancy has been uncomplicated to date.  The patient is Rh(D) positive and her husband is Rh(D) negative.  Their 3-year-old son is healthy, and he is Rh(D) positive.  A year prior, the patient had a missed abortion requiring suction curettage.  She has no chronic medical problems and no other surgeries.  The patient is taking a prenatal vitamin and does not use tobacco, alcohol, or illicit drugs.  Vital signs are normal.  Fetal anatomic ultrasound a week prior demonstrated an echogenic intracardiac focus but no other abnormalities.  Which of the following is the most accurate statement to the patient regarding hemolytic disease due to Rh(D) incompatibility?

Accepted Answer

Explanation: 11ec2b69_bf7d_b67a_8f63_5d2782f2e985_MD0005_00 Rh(D) incompatibility is possible only in an Rh(D)-negative mother and Rh(D)-positive father. It occurs when an Rh(D)-negative mother is exposed to the Rh(D) antigen, typically from fetomaternal hemorrhage in a prior pregnancy with an Rh(D)-positive fetus. The mother then produces IgG anti-D antibodies that cross the placenta and destroy Rh(D)-positive fetal red blood cells (eg, hemolysis) in a subsequent pregnancy. When Rh(D) incompatibility is unrecognized or untreated, alloimmunization can develop, resulting in hemolytic disease of the fetus or newborn. Disease ranges from mild anemia to severe hydrops fetalis. Progression of disease occurs when severe fetal anemia results in cardiac failure and subsequent edema (eg, pleural and pericardial effusions, ascites). Serial ultrasounds monitor the progression of fetal anemia, which can be treated with in utero red blood cell transfusions. This patient is Rh(D) positive; there is no risk of hemolytic disease to her newborn due to Rh(D) incompatibility. Regardless of the baby's blood type, the mother will never produce antibodies against the Rh(D) antigen (Choice C). However, antibodies to less common antigens [eg, Kell, Rh(c), Rh(E)] can also cause hemolytic disease; therefore antibody screening is performed in all pregnant women regardless of Rh(D) status. (Choice A) Maternal Rh(D) alloimmunization is diagnosed when an antibody screen and titers are positive for anti-D. In patients with elevated titer levels (>1:8), serial ultrasounds are performed to monitor for signs of anemia and hydrops fetalis. Fetal anemia can be treated with intrauterine fetal transfusion in an attempt to prevent the development of hydrops fetalis. (Choices B and D) When a mother is Rh(D) negative and a father is Rh(D) positive, there is a risk of hemolytic disease if the mother has been previously exposed to Rh(D) antigens (eg, prior pregnancy, blood transfusion). Rh(D)-negative patients can decrease the risk of an infant with hemolytic disease by receiving anti-D immune globulin [eg, Rho(D) immune globulin] during each pregnancy, including abortions and ectopic pregnancies. Educational objective: Hemolytic disease of the newborn due to Rh(D) incompatibility is possible only in an Rh(D)-negative mother and Rh(D)-positive father. References: Red cell alloimmunization in RhD positive pregnant women and neonatal outcome. (http://www.ncbi.nlm.nih.gov/pubmed/27324408) Hemolytic disease of the fetus and newborn: modern practice and future investigations. (http://www.ncbi.nlm.nih.gov/pubmed/27397673)

Question 13

A 32-year-old woman is brought to the emergency department after she was found wandering aimlessly in the street. She lives in a homeless shelter and has not received medical care in several years. The patient has no chronic medical problems or previous surgeries. She has a history of intravenous drug use and 16-pack-year cigarette use. Temperature is 37.2 C (99 F), blood pressure is 120/60 mm Hg, and pulse is 94/min. BMI is 19 kg/m². On examination, the patient is mildly agitated, but oriented to person and place. Her sclerae are icteric. The mucous membranes are moist, but there is evidence of poor oral hygiene and multiple dental caries. There are scattered bilateral petechial lesions on the extremities and trunk. Cardiac, abdominal, and neurologic examinations are unremarkable. Bimanual pelvic examination reveals a uterus consistent with 14 weeks gestation. Laboratory results are as follows: Urine pregnancy test is positive. Which of the following is the most likely diagnosis?

Accepted Answer

Explanation: 11ec2b69_bf81_d531_8f63_fd38f73eae69_MD0005_00 This patient has altered mental status, a petechial rash, renal failure, thrombocytopenia, and a microangiopathic hemolytic anemia (eg, hyperbilirubinemia, scleral icterus), a presentation consistent with thrombotic thrombocytopenic purpura (TTP). Other features of TTP include fever, seizure, coma, and gastrointestinal symptoms (eg, nausea, abdominal pain). TTP occurs as a result of an either inherited or acquired deficiency in the activity of ADAMTS13, a von Willebrand factor-cleaving protease. Pregnancy is associated with an ADAMTS13 deficiency that becomes more pronounced with increasing gestational age and persists into the postpartum period and can precipitate TTP. TTP is a life-threatening condition that requires emergency treatment with plasma exchange. (Choices A and B) Acute fatty liver of pregnancy typically presents in the third trimester with nausea, vomiting, epigastric pain, malaise, and elevated transaminases. HELLP syndrome typically presents in the third trimester with hemolytic anemia, thrombocytopenia, and elevated transaminases. These diagnoses are unlikely in this patient due to the early gestational age and normal transaminases. (Choice C) Serum sickness typically presents with a rash and renal failure 1-2 weeks after antigenic exposure. However, patients also typically have an associated polyarthralgia, which is not seen in this patient. (Choice D) Wernicke encephalopathy (eg, thiamine deficiency) typically presents with an altered mental status. However, Wernicke encephalopathy also presents with oculomotor dysfunction (eg, nystagmus) and gait ataxia, which are not seen in this patient. Educational objective: Thrombotic thrombocytopenic purpura (TTP) presents with a petechial rash, neurologic abnormalities, thrombocytopenia, and microangiopathic hemolytic anemia. TTP can occur during pregnancy or in the postpartum period. Treatment is with plasma exchange. References: Thrombotic thrombocytopenic purpura: from diagnosis to therapy. (http://www.ncbi.nlm.nih.gov/pubmed/26418759) Pregnancy associated thrombotic thrombocytopenic purpura: practical issues for patient management. (http://www.ncbi.nlm.nih.gov/pubmed/26626962)

Question 14

A 45-year-old woman comes to the emergency department due to worsening fatigue.  Today, she was so tired that she became short of breath doing household chores.  She has also had "spots" on her extremities and seems to bruise very easily.  The patient has had no fever, night sweats, cough, chest pain, palpitations, or abdominal pain.  She has no chronic medical problems and has had no recent cold or flu symptoms.  She does not take any medications and does not use tobacco, alcohol, or illicit drugs.  Temperature is 38 C (100.4 F), blood pressure is 110/60 mm Hg, pulse is 92/min, and respirations are 16/min.  Physical examination shows moist mucous membranes, clear lung fields, and normal heart sounds.  The abdomen is soft and nontender with no hepatosplenomegaly.  Neurologic examination is within normal limits.  The extremities have no edema, but there are scattered petechiae and ecchymoses bilaterally.  Laboratory results are as follows:  Chest x-ray is normal.  A peripheral blood smear is shown in the exhibit.  Which of the following is the goal of the first-line therapy for this patient's current condition?

Accepted Answer

Explanation: 11ec2b69_bf82_7173_8f63_c7e79ac0d8b1_MD0005_00 This patient with fatigue and bruising has microangiopathic hemolytic anemia (MAHA), severe thrombocytopenia, and normal coagulation studies, indicating likely thrombotic thrombocytopenic purpura (TTP). TTP is an acquired syndrome due to the formation of autoantibodies against ADAMTS13, a plasma metalloprotease responsible for cleaving ultralarge strings of von Willebrand factor (vWF) off the vascular endothelial wall. When levels of ADAMTS13 become severely deficient, uncleaved strings of vWF trap and activate platelets, resulting in diffuse microvascular thrombi. This causes the following: Platelet consumption, leading to severe thrombocytopenia Intravascular red blood cell shearing, leading to signs of MAHA such as schistocytes and elevated indirect bilirubin, lactate dehydrogenase, and aminotransferases Organ ischemia, leading to neurologic and renal dysfunction (classically) Patients who have clinical and laboratory data that support the diagnosis of TTP require urgent treatment with plasma exchange. This removes the autoantibody against ADAMTS13 and replenishes the enzyme with ADAMTS13 from donor serum. (Choice A) Desmopressin increases serum concentrations of vWF and is often used in von Willebrand disease to stop minor episodes of bleeding. Patients with this disease may have easy bruising and petechiae, but MAHA is uncommon. (Choice C) Patients with disseminated intravascular coagulation usually have signs of thrombocytopenia and MAHA due to coagulation cascade activation. However, disseminated intravascular coagulation is usually associated with prolonged coagulation testing, unlike this patient. (Choice D) Antibodies against platelet antigens are responsible for immune thrombocytopenia, which may cause thrombocytopenia, bruising, and petechiae. However, immune thrombocytopenia is not associated with MAHA. (Choice E) Platelet transfusions are not recommended for patients with TTP unless severe bleeding occurs. The additional platelets may worsen the ongoing intravascular thrombosis. Educational objective: Thrombotic thrombocytopenic purpura is due to acquired autoantibodies against the metalloprotease ADAMTS13, which cleaves ultralarge chains of von Willebrand factor off the vascular endothelium. Uncleaved chains trap and activate platelets, resulting in severe thrombocytopenia and microangiopathic hemolytic anemia (eg, schistocytes, elevated indirect bilirubin). Urgent treatment with plasma exchange removes the autoantibody and replenishes ADAMTS13. References: Optimal preprocedural platelet transfusion threshold for central venous catheter insertions in patients with thrombocytopenia. (http://www.ncbi.nlm.nih.gov/pubmed/21517892)

Question 15

A 45-year-old male returns to clinic for follow-up examination.  He has no current complaints and has been feeling well recently.  Past medical history is significant for hypertension and gastroesophageal reflux disease.  He also had a left knee operation eight months ago that was complicated by a postoperative deep vein thrombosis (DVT) of the left leg.  He has no other personal history of blood clots, and there is no family history of clotting disorders.  Currently, his vital signs are stable and his physical examination is within normal limits.  Specifically, there is no swelling or calf tenderness of the left leg.  He took warfarin on a daily basis for a total of six months after the DVT was diagnosed and then stopped taking it because he no longer wanted to deal with monitoring his INR.  This is his first visit to clinic since being discharged after his knee operation.  Which of the following is the next best step in treating this patient's prior DVT?

Accepted Answer

Explanation: In contrast to patients with idiopathic DVTs, patients with DVTs secondary to reversible or time-limited risk factors (eg, surgery, pregnancy, oral contraceptive use, or trauma) should be treated for at least three months but not longer than six months, as the risk of a recurrent DVT after six months of treatment is very low. In patients with idiopathic DVTs, at least six months of warfarin therapy is also recommended, with re-evaluation at the end of the treatment cycle for long-term anticoagulation. This decision is individualized and should be based on the risk to benefit ratio for anticoagulation. Because this particular patient's DVT occurred after a major surgery and he has no other personal or family history of venous thromboembolic disease, the six months of warfarin therapy he has already received is adequate treatment. He does not require further anticoagulation at this time. (Choice A and B)There is no need to initiate treatment with unfractionated or low-molecular weight heparin at this time, as this patient has no evidence of recurrent thromboembolic disease and has already received adequate anticoagulation. (Choice C) Because this patient's risk of a recurrent DVT after six months of warfarin therapy is very low (less than 3% in the first year), he requires no further anticoagulation. (Choice E)As there is no suspicion of a recurrent DVT at this time, a lower extremity venous scan is not likely to be helpful. Educational objective: In a patient who develops a DVT as a result of a reversible or time-limited risk factor (eg, surgery, pregnancy, oral contraceptive use, or trauma), warfarin anticoagulation should be continued for a minimum of three months. Treatment for longer than six months, however, is not necessary.

Question 16

A newborn boy is evaluated on arrival in the nursery.  He was born 3 hours ago by spontaneous vaginal delivery at 40 weeks gestation after an uncomplicated pregnancy.  Apgar scores were 9 at 1 minute and 10 at 5 minutes after birth.  His mother has no significant medical history and does not take any medications.  Temperature is 36.7 C (98 F), pulse is 124/min, and respirations are 26/min.  He is awake, alert, and active with a strong cry.  His head is normocephalic and atraumatic with an open flat anterior fontanelle.  Pupils are equal and reactive to light and accommodation, and red reflexes are present bilaterally.  The nares are patent, there is no cleft lip or palate, and the pharynx is not erythematous.  Clavicles are intact without crepitus.  S1 and S2 are normal without murmurs, and lungs are clear to auscultation bilaterally.  The abdomen is soft, nontender, and nondistended with normal bowel sounds and no organomegaly.  Femoral pulses are normal and symmetrical.  All extremities move spontaneously and there is no edema.  There are no rashes, skin lesions, or jaundice, but the complexion appears ruddy with generalized erythema.  Blood samples obtained from the heel through simple prick method reveal a hematocrit of 70%. 
What is the most appropriate next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf7a_8228_8f63_03773155b374_MD0005_00 Neonatal polycythemia, which affects up to 5% of newborns, is defined as a hematocrit >65% or hemoglobin >22 g/dL. It is most often observed at 2-3 hours of life as a result of increased hemoglobin production, possibly due to unstable newborn vasomotor factors or in response to relative uterine hypoxia. Factors that contribute to the development of polycythemia include delayed clamping of the umbilical cord, gestational diabetes, maternal hypertension, and intrauterine growth restriction. In most cases, newborns are asymptomatic and the hematocrit value declines to baseline levels within the first 24 hours of life. However, polycythemia can be associated with complications (eg, hypoglycemia, hyperbilirubinemia, hyperviscosity, hypoperfusion, tissue hypoxia), due mostly to increased red blood cell volume. There may be significant variability in measurements with capillary samples (eg, heel prick). Therefore, if the hematocrit is >65% on a heel prick, it should be confirmed by rechecking a sample from peripheral venous blood, which is more reliable, unaffected by changes in temperature and blood flow, and often up to 15% lower than a hematocrit taken from a capillary sample (Choice D). (Choice A) Checking blood type and Coombs test is an important part of the workup for a newborn with suspected ABO incompatibility. However, ABO incompatibility leads to hemolytic anemia rather than polycythemia. (Choices B and C) Checking serum blood urea nitrogen and creatinine levels helps to determine hydration status, as dehydration can be both a source and an outcome of polycythemia. Hypothyroidism or hyperthyroidism can also cause polycythemia. However, it is more important to determine whether polycythemia is actually present before conducting further workup. Educational objective: Neonatal polycythemia is diagnosed when the peripheral venous hematocrit is >65%. High hematocrit levels that are obtained from capillary samples (usually from a heel prick) are unreliable and must be confirmed through venous blood sampling. References: Management of polycythemia in neonates. (http://www.ncbi.nlm.nih.gov/pubmed/20725868)

Question 17

A 78-year-old man comes to the office for the evaluation of persistent, severe, low back pain.  The pain does not radiate down to his legs, and is not associated with bladder or bowel disturbances.  He has metastatic prostate cancer, which has progressed despite hormonal therapy and chemotherapy.  A bone scan done 6 weeks ago revealed the presence of 2 vertebral metastases in the L4 and L5 vertebral bodies.  He was started on high-dose narcotic analgesics at that time.  He says that the narcotics have "taken the edge" off the pain, but he continues to have severe debilitating pain.  Neurological examination of the lower extremities is unremarkable.  A repeat bone scan reveals results similar to the previous scan results.  Which of the following is the next most appropriate step in controlling this patient's symptoms?

Accepted Answer

Explanation: The axial skeleton is the most common site of spread of prostate cancer, which can cause significant pain and functional impairment. The primary goal of treatment in patients with metastatic, hormone-refractory prostate cancer is palliation. Specific aims in the management are adequate pain relief, improvement of the functional status, and prevention of vertebral compression fractures and subsequent spinal cord compression. Focal external beam radiation therapy is the treatment of choice for palliation of pain in patients with metastatic, advanced hormone-refractory prostate cancer. It should be used in patients with a single or few focal bone lesions in which the pain is not adequately controlled with narcotic analgesics. (Choice B) The patient has a history of progressive, metastatic prostate cancer despite hormone therapy. It is unlikely that he will respond adequately to subsequent hormone manipulation. (Choice C) Corticosteroids reduce inflammation by inhibiting prostaglandin synthesis. These drugs are only useful when inflammation or edema surrounding the tumor causes pain secondary to compression or visceral distention. These are also useful in patients with epidural spinal cord compression. (Choice D) Surgery is only indicated in patients with pathological vertebral compression fractures or signs and symptoms of epidural spinal cord compression secondary to the metastases. Educational objective: External beam radiation therapy should be used for pain alleviation in patients with single or few focal bone metastatic lesions due to hormone-refractory prostate cancer.

Question 18

A 5-year-old boy is brought to the emergency department with severe leg pain that started 6 hours earlier.  His mother says that their heating system broke last night so she "tried to keep him warm with lots of blankets."  The patient was given ibuprofen and oxycodone at home without relief of pain.  He played outside with his brother yesterday but did not experience any trauma or injury.  He has not had fever, cough, vomiting, or rash.  Medical history includes mild persistent asthma and sickle cell disease, and he has been hospitalized once for a vaso-occlusive pain episode.  Temperature is 37.2 C (99 F), blood pressure is 100/62 mm Hg, pulse is 150/min, and respirations are 20/min.  Physical examination shows a young child lying in bed in significant discomfort, crying and holding his left leg.  Mucous membranes are moist and capillary refill is <2 seconds.  The lungs are clear to auscultation, and the abdomen is soft, nontender, and nondistended without organomegaly.  The left anterior calf is markedly tender to palpation but does not have erythema, warmth, or swelling.  A peripheral intravenous line is inserted, and a complete blood count is drawn. 
What is the best next step in management of this patient?

Accepted Answer

Explanation: 11ec2b69_bf7f_d95e_8f63_0b44de50d2b6_MD0005_00 The most common manifestation of sickle cell disease (SCD) is a vaso-occlusive episode (VOE). VOEs are acute episodes of minor to severe pain that typically affect the back, chest, abdomen, or extremities. Triggers can include dehydration, infection, stress, weather changes, or menstruation. Treatment often requires hospitalization and consists of prompt administration of oral or intravenous pain medication and gentle rehydration. Outpatient therapy typically includes nonsteroidal anti-inflammatory drugs and acetaminophen for mild pain and oral opiate medications (eg, oxycodone) for moderate pain. Intravenous opiates (eg, morphine) are the first-line treatment in the emergency department and should be given within 30 minutes of arrival. Rehydration is also a key component of VOE management, as dehydration is known to cause sickling and worsen VOEs. Intravenous fluids are indicated for hypovolemic or hypotensive patients as initial fluid resuscitation. This patient's blood pressure is normal for age, and pain medications should therefore be given first. (Choice A) Patients with SCD are at increased risk for bacteremia, specifically from encapsulated organisms due to functional asplenia. All patients with SCD with fever should have a blood culture drawn and be started on antibiotics. Because this patient is afebrile, a blood culture is not indicated. (Choice C) Codeine is contraindicated in children age <12 due to unpredictable metabolism resulting in increased conversion to active opioid metabolites, resulting in life-threatening respiratory depression. (Choice D) This patient did not improve on oral opiate therapy at home, and therapy should be escalated. Intravenous opiates are preferred for hospitalized patients or those in the emergency department with significant pain. (Choice E) The most likely cause of pain in this patient is a VOE, which is a clinical diagnosis and does not require imaging. Fracture or osteomyelitis is unlikely in the absence of trauma or fever. Educational objective: Patients with sickle cell disease who have a severe vaso-occlusive episode and are hemodynamically stable should be treated promptly with intravenous opioids. References: Evidence-based management of sickle cell disease in the emergency department. (http://www.ncbi.nlm.nih.gov/pubmed/22164362) Management of sickle cell disease: summary of the 2014 evidence-based report by expert panel members. (http://www.ncbi.nlm.nih.gov/pubmed/25203083)

Question 19

A 42-year-old Caucasian woman comes to the emergency department because of right-sided neck pain, persistent cough, and dyspnea for the past three days.  Her past medical problems include hypertension and obesity.  She takes enalapril and hydrochlorothiazide.  She has smoked one pack of cigarettes daily for the past 25 years.  She does not drink alcohol.  She works as an executive secretary.  Her temperature is 37.8C (100 F), blood pressure is 130/80 mm Hg, pulse is 92/min and respirations are 18/min.  Examination shows decreased breath sounds in the upper part of the right lung.  There is moderate swelling and erythema of the neck, moderate right jugular vein dilatation, and increased venous marks in the right arm.  Her serum creatinine level is 0.8 mg/dL.  A chest x-ray reveals a right-sided opacity.  Which of the following is the most appropriate immediate step in the management of this patient?

Accepted Answer

Explanation: The patient's history, physical findings, and radiologic findings suggest superior vena cava syndrome (SVCS) secondary to a lung malignancy. At least 80% of the cases of SVCS are due to bronchogenic carcinoma. The classic presentation of SVCS begins with dyspnea, persistent cough, facial fullness and neck pain, and progresses into hoarseness, dysphagia, chest pain and syncope. Pertinent physical findings are edema and erythema of the neck (which may sometimes compromise the face), and dilated veins of the arms and neck. Advanced disease is manifested by cyanosis, collateral veins in the thorax, ocular proptosis and lingual edema. The best diagnostic test for SVCS is a contrast CT scan of the chest and neck, which will reveal an obstruction of the superior vena cava due to the pulmonary mass, the metastatic nodes, or an intravenous thrombus. CT scan is very useful because it can reveal the extent of obstruction and provide a histopathologic diagnosis (via percutaneous biopsy), which will determine the particular therapeutic regimen required to manage the underlying malignancy. (Choice E) Magnetic resonance imaging (MRI) is a more expensive procedure, and does not offer any visual advantage over computed tomography. It is only used when a patient is allergic to the contrast dye used in CT scan, or when venous access cannot be obtained for contrast-enhanced studies. (Choice C) Immediate endotracheal intubation may be performed if there exists a risk of sudden airway occlusion, such as in patients with mediastinitis and deep neck infection; however, this patient does not have a history of esophageal disease, upper respiratory tract infection, fever, or chills, to make us suspect mediastinitis. (Choice A) The erythema of the patient is due to venous occlusion and possible thrombosis, not to facial or neck cellulitis. Antibiotic therapy may be subsequently needed if the patient is found to have an infection; however, it is not necessary at this point. (Choice D) Biochemical and hematological tests may be obtained after CT scan evaluation. Educational objective: Superior vena cava syndrome must be suspected in any patient who has a high risk of malignancy (e.g., family history or smokers) and presents with dyspnea, orthopnea, neck pain and swelling, and has cervical and upper extremities venous dilatation. The best diagnostic test to perform is computerized tomography of the neck and chest.

Question 20

A 1-year-old child is diagnosed with severe microcytic/hypochromic anemia.  His past medical history is insignificant.  His family history is significant for an early death of his uncle from 'a blood disease'.  Physical examination reveals hepatomegaly and splenomegaly.  Subicteric discoloration of the sclerae is present.  If this child survives several years after the diagnosis, severe organ damage due to iron overload is best explained by which of the following?

Accepted Answer

Explanation: Severe microcytic/hypochromic anemia in this patient is most likely explained by thalassemia major, a severe congenital hemolytic anemia. Patients with this disorder usually die early in life due to relentless anemia and catastrophic expansion of erythroid precursors. Hypertransfusion therapy has a great role in treated patients (i.e. the child may survive several years after the diagnosis). Hypertransfusion regimen can suppress the effects of chronic severe anemia and extramedullary hematopoiesis, but result in significant iron overload and resultant organ damage. (Choices A and E)Interestingly, iron metabolism is significantly affected even without transfusion therapy in these patients. Iron overload is caused by erythroid hyperplasia, red blood cell destruction, and ineffective hematopoiesis. (Choice D)The transferrin saturation level is high in these patients. (Choice B)Iron chelators, not supplements, are given in an attempt to decrease iron deposition in tissues. Educational Objective: Hypertransfusion regimen results in significant iron overload and resultant organ damage in patients with severe congenital anemias.

Exam 1: Advanced Clinical Medicine