A 47-year-old man comes to a homeless shelter clinic due to 2 weeks of skin rash. The patient was recently hospitalized and treated for an infection, but he is unsure of the details. He was diagnosed with HIV 10 months ago and is not on antiretroviral therapy. He also has a history of chronic kidney disease and hypertension. He takes no medication regularly. The patient drinks 1-2 cans of beer daily and does not use tobacco. Temperature is 37.2 C (99.0 F), blood pressure is 120/70 mm Hg, pulse is 80/min, and respirations are 14/min. BMI is 17 kg/m². Oropharyngeal thrush is present. Cardiopulmonary auscultation reveals clear lung fields, and normal first and second heart sounds without murmur or gallop. The abdomen is soft and nontender. The liver is palpable 3 cm below the costal margin, and mild splenomegaly is present. Neurological examination shows no abnormalities. Multiple small papules with central umbilication are present on the face, neck, trunk, and upper thighs. Some of the lesions have central necrosis and are covered with a hemorrhagic crust. Which of the following is most likely to result in a diagnosis for this patient?

Question

Quizplus · Accepted Answer

Explanation: This patient with untreated HIV developed several papular lesions with central umbilication and necrosis over 2 weeks, raising strong suspicion for cutaneous cryptococcosis. Diagnosis requires biopsy of a lesion; histopathological examination after staining (eg, periodic acid-Schiff, Gömöri methenamine silver nitrate) typically reveals hyperplasia of the overlying dermis with underlying granulomas surrounding encapsulated yeasts. encapsulated yeasts Cutaneous cryptococcosis is usually treated with >2 weeks of intravenous amphotericin B and oral flucytosine followed by a year of oral fluconazole (higher dose for 8 weeks, then maintenance). (Choice B) Infectious endocarditis can be diagnosed with an echocardiogram and often manifests with cutaneous lesions (eg, splinter hemorrhages, petechiae, Janeway lesion, Osler nodes). This patient with untreated HIV who has several papular, umbilicated lesions is more likely to have cutaneous Cryptococcus. (Choice C) Fungal blood cultures are often positive in severe, disseminated cryptococcal disease. However, the etiology of the lesion must be determined with biopsy (more sensitive and specific than blood cultures), especially as patients with untreated HIV may have multiple ongoing opportunistic infections. (Choice D) Skin scrapings with microscopic evaluation can often diagnose fungal infection such as tinea or candidiasis. Cryptococcus typically requires a biopsy for cutaneous diagnosis. (Choice E) Urine antigen testing is not typically performed for cryptococcosis; however, serum antigen testing is often useful for diagnosis. Educational objective: Cutaneous cryptococcosis is typically diagnosed by lesion biopsy with histopathological examination.

A 47-Year-Old Man Comes to a Homeless Shelter Clinic Due