Early-Onset Methemoglobinemia in an HIV Patient Receiving Dapsone for PCP Prophylaxis Without G6PD Deficiency: A Case Report G6PD Eksikliği Olmayan ve PCP Profilaksisi için Dapson Alan Bir HIV Hastasında Erken Başlangıçlı Methemoglobinemi: Bir Vaka Raporu

Kakalıçoğlu Özden D., Cengiz C., Öztürk Çiftci E., Pehlivanoğlu F.

Mediterranean Journal of Infection, Microbes and Antimicrobials, cilt.15, 2026 (ESCI, Scopus, TRDizin)

Özet

Dapsone is used for Pneumocystis jirovecii pneumonia (PCP) prophylaxis in patients with human immunodeficiency virus (HIV) infection who cannot tolerate trimethoprim–sulfamethoxazole (TMP-SMX), the first-line agent. Methemoglobinemia is a known adverse effect of dapsone, usually associated with glucose-6-phosphate dehydrogenase (G6PD) deficiency, but it may also occur in patients with normal enzyme activity. We report a case of early-onset methemoglobinemia in a newly diagnosed HIV-infected patient without G6PD deficiency receiving dapsone for PCP prophylaxis. A 24-year-old male with a CD4 T-cell count of 32/mm3 developed decreased oxygen saturation approximately 72 hours after starting dapsone. Despite minimal symptoms, methemoglobin levels increased up to 11.5%. Dapsone was discontinued, and the patient was treated with methylene blue with rapid improvement. Although dapsone-induced methemoglobinemia is well described, reports in HIV-infected patients receiving dapsone for PCP prophylaxis are limited. This case highlights that methemoglobinemia may occur without G6PD deficiency and emphasizes early recognition.