A 66-year-old man comes to the emergency department due to a 3-day history of fever, chills, dysuria, and perineal pain. The patient has never had similar symptoms before, although he has had occasional nocturia and urinary hesitancy over the last 2 years. His other medical conditions include type 2 diabetes mellitus and hypertension. The patient does not use tobacco, alcohol, or illicit drugs. He has not traveled recently and is not sexually active. Temperature is 39 C (102.2 F), blood pressure is 124/78 mm Hg, and pulse is 106/min. The abdomen is soft and nontender with no costovertebral angle tenderness. Digital rectal examination shows a smoothly enlarged and tender prostate. External genitalia are normal with no scrotal tenderness. There is no urethral discharge. The remainder of the examination shows no abnormalities. Urinalysis reveals bacteriuria and pyuria. Which of the following pathogens is most likely responsible for this patient's current symptoms?

Question

A 66-year-old man comes to the emergency department due to a 3-day history of fever, chills, dysuria, and perineal pain.  The patient has never had similar symptoms before, although he has had occasional nocturia and urinary hesitancy over the last 2 years.  His other medical conditions include type 2 diabetes mellitus and hypertension.  The patient does not use tobacco, alcohol, or illicit drugs.  He has not traveled recently and is not sexually active.  Temperature is 39 C (102.2 F), blood pressure is 124/78 mm Hg, and pulse is 106/min.  The abdomen is soft and nontender with no costovertebral angle tenderness.  Digital rectal examination shows a smoothly enlarged and tender prostate.  External genitalia are normal with no scrotal tenderness.  There is no urethral discharge.  The remainder of the examination shows no abnormalities.  Urinalysis reveals bacteriuria and pyuria.  Which of the following pathogens is most likely responsible for this patient's current symptoms?

Quizplus · Accepted Answer

11ec160b_386a_141f_9249_a9da204a555a_MD0001_00 This patient has fever, dysuria, and prostatic tenderness, consistent with acute bacterial prostatitis (ABP). ABP is most commonly caused by reflux of urine and organisms from the bladder and urethra into the prostatic ducts, although it can occasionally be caused by direct inoculation (eg, prostate biopsy) or hematogenous seeding from remote infection (eg, endocarditis). The risk of developing ABP is greater in patients with diabetes mellitus, anatomic abnormalities (eg, strictures), or bladder catheterization. As with other urinary tract infections, the most common organisms in ABP include enteric gram-negative bacilli, predominantly Escherichia coli, because of virulence factors (eg, adhesins on bacterial fimbriae) that allow it to adhere onto mucosal or urothelial cells. The other bacteria (also gram-negative bacilli) that commonly cause ABP include Proteus, Klebsiella, Pseudomonas. (Choices A and E) Sexually transmitted organisms (eg, Chlamydia trachomatis, Neisseria gonorrhoeae) commonly cause urethritis and/or urogenital infections that can involve the prostate, but this typically occurs in younger, sexually active men (this patient is older and not sexually active). (Choice B) Coccidioides infections most commonly cause community-acquired pneumonia in endemic areas (eg, California, Arizona), but they can also cause dermatologic (eg, erythema nodosum or multiforme) or rheumatologic (eg, arthralgias) manifestations. (Choices D and H) Mycoplasma hominis and Ureaplasma urealyticum commonly colonize the genitourinary tract, but they have not been proven to be a significant cause of symptomatic genitourinary infections. (Choice F) Gram-positive skin flora (eg, Staphylococcus aureus) most commonly cause skin and soft tissue infections. Although patients with S aureus bacteremia can develop localized infections throughout the body (eg, endocarditis, osteomyelitis, organ abscess), isolated ABP would be rare. (Choice G) Coagulase-negative staphylococci (eg, S saprophyticus) are a common cause of acute cystitis in young women. Educational objective: Acute bacterial prostatitis is usually caused by reflux of urine and organisms from the bladder and urethra. The risk is greater in patients with anatomic abnormalities (eg, strictures) or bladder catheterization. Escherichia coli is the most common cause of acute bacterial prostatitis and other urinary tract infections because of adhesins on its fimbriae that promote adherence to urothelial or mucosal cells. __________ References: Acute bacterial prostatitis: diagnosis and management. (http://www.ncbi.nlm.nih.gov/pubmed/26926407) The etiology and management of acute prostatitis. (http://www.ncbi.nlm.nih.gov/pubmed/21403661)

A 66-Year-Old Man Comes to the Emergency Department Due to a 3-Day