Dapsone-Induced Hemolytic Anemia, Severe Acute Liver Injury and Clinically Suspected Methemoglobinemia in a Patient with Hansen's Disease: A Rare Case Report.

Abstract

Background
Dapsone is a key component of multidrug therapy (MDT) for Hansen's disease but is associated with serious adverse effects, including methemoglobinemia, hemolytic anemia, and hepatotoxicity. The simultaneous occurrence of these complications is rare and potentially life-threatening. Early recognition is critical, especially in resource-limited settings where advanced diagnostic tools may not
be readily available.
Case Report
The patient presented with jaundice, fever, and breathlessness approximately one month after initiation of dapsone therapy. Examination revealed pallor, icterus, and edema. Laboratory findings showed severe hyperbilirubinemia (>25 mg/dL), elevated transaminases, anemia (hemoglobin ~8 g/dL), markedly elevated lactate dehydrogenase (1705 U/L), and negative Coombs test, consistent with non-immune hemolysis. Inflammatory markers were elevated, and arterial blood gas analysis indicated metabolic acidosis. Methemoglobinemia was clinically diagnosed by the treating team.
Imaging revealed pleural effusion and ascites, suggesting systemic involvement. Dermatology consultation suggested dapsone hypersensitivity syndrome, and dapsone was discontinued. The overall findings were consistent with dapsone-induced multisystem toxicity involving hepatic, hematological, and respiratory systems.
Conclusion
This case highlights a rare but severe presentation of dapsone-induced methemoglobinemia, hemolytic anemia, and acute liver failure. Clinicians should maintain a high index of suspicion for dapsone toxicity in patients presenting with jaundice, anemia, and respiratory symptoms shortly after initiation of therapy. Early drug withdrawal and prompt supportive management are essential to
prevent life-threatening complications.