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A Case of Cyanosis With Saturation Gap: Dapsone-Induced Methemoglobinemia
Mahammed Khan Suheb1, Farheen Naaz2, Tyler K Anderson3
1Internal Medicine, University of Nebraska Medical Center, Omaha, USA.
Abstract:
Dapsone is an antibiotic used in the management of dermatologic infections and opportunistic infection prophylaxis in developed countries. Methemoglobinemia (MetHb) is a known complication of dapsone use that can result in cyanosis. MetHb is an aberrant form of hemoglobin produced physiologically by auto-oxidation. An impairment in the process of auto-oxidation due to genetic defects or the use of drugs/toxins causes its levels to rise. Management involves timely recognition and the use of methylene blue (MB) or ascorbic acid. We describe the diagnosis and management of a patient with acquired MetHb as a result of dapsone use.
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