Review Question - QID 214626

A 34-year-old African-American woman presents to the emergency department with sudden-onset dark urine and pallor. She also complains of back pain and fatigue. She has a history of celiac disease. Due to poor adherence to a gluten-free diet, the patient’s recently developed dermatitis herpetiformis. She was started on dapsone 2 days ago. The patient drinks socially and had 6 beers last night. Labs are drawn, as shown below:

Leukocyte count: 11,000/mm^3
Hemoglobin: 8.0 g/dL
Platelets: 200,000/mm^3

Serum:
Aspartate aminotransferase (AST, GOT): 15 U/L
Alanine aminotransferase (ALT, GPT): 12 U/L
Total bilirubin: 3.8 mg/dL
Direct bilirubin: 0.2 mg/dL
Haptoglobin: 36 g/dL (normal range: 50-200 g/dL)
Lactate dehydrogenase (LDH): 125 U/L
Glucose-6-phosphate dehydrogenase (G6PD): 8.5 U/g (normal range: 5.5 to 20.5 U/g)

A peripheral smear shows red blood cells with semicircular portions removed from the cells' periphery. Inclusion bodies are seen with methylene blue staining. Which of the following is the most likely diagnosis?