Extracorporeal treatments in a dapsone overdose: a case report.

Introduction: Intentional dapsone intoxication can be life-threatening. There is limited data on the clinical effect of extracorporeal treatments (ECTRs) on dapsone elimination. We describe a case of severe dapsone toxicity treated with different ECTRs.

Case Details: A 23-year-old woman was admitted 2.5 h after ingesting 2.2 g of dapsone. She developed methemoglobinemia (39.9%) and showed signs of toxicity (hemodynamic instability and altered mental status) despite multiple-activated charcoal, methylene blue, vasopressors and endotracheal intubation. Continuous venovenous hemofiltration (CVVH) was then initiated for 5 h, followed by intermittent hemodialysis with hemoperfusion (IHD-HP) for 4 h, and CVVH for another 48 h. The platelet count decreased to 32 × 10/L 3 h after IHD-HP. The elimination half-life of dapsone was 2.0 h during IHD-HP, and 14.2 h during CVVH. Mean dapsone clearance with IHD was 62 mL/min versus 22 mL/min with CVVH. IHD removed 95.3 mg, and CVVH removed 67.8 mg over 3.8 h. No rebound occurred following ECTR cessation. The toxicokinetics of dapsone metabolites were also accelerated during ECTR. The patient was extubated after 3.5 days and discharged without sequelae after 7 days.

Discussion: Dapsone clearance was enhanced by ECTR, especially by IHD-HP. However, HP was associated with severe asymptomatic thrombocytopenia.