A 23-Year-Old African American Man Returns to the Physician Because

question 360

Multiple Choice

A 23-year-old African American man returns to the physician because of jaundice, dark urine, and fatigue.  He was seen in the clinic 4 days ago for sinusitis and was prescribed trimethoprim-sulfamethoxazole.  He reports that his sinus symptoms have improved.  He has no other medical problems and takes no other medications.  He does not use tobacco, alcohol, or illicit drugs.
Vitals signs are normal.  Physical examination shows scleral icterus.  Abdominal examination is unremarkable with no evidence of hepatosplenomegaly.
Laboratory results are as follows:

Peripheral blood smear shows many bite cells.  Direct and indirect Coombs' test is negative.  Red blood cell glucose-6-phosphate dehydrogenase level is normal.
Which of the following is the most likely cause of his anemia?

• A)Autoimmune hemolytic anemia
• B)Glucose-6-phosphate dehydrogenase deficiency
• C)Paroxysmal nocturnal hemoglobinuria
• D)Pyruvate kinase deficiency
• E)Microangiopathic hemolytic anemia

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Definitions:

Epidermis

The external layer of skin which serves as a water-resistant barrier and determines our skin color.

Stratum

A layer or a series of layers of tissue in an organism or a part of its structure.

Epidermis

The surface layer of the skin that acts as a barrier to water and defines the color of our skin.

Stratum

A layer or level within a structure, such as skin or geological formations.