Dapsone methemoglobinemia: a case report

Abstract

Objective: Report a case of Methemoglobinemia induced by Dapsone in a young patient undergoing treatment for Leprosy at Hospital Santa Casa de Misericórdia de Vitória and write a literature review based on the topic. Methods: Observational, descriptive and qualitative case report study with literature review based on original scientific articles in the databases Medline, PubMed, Latin American and Caribbean Literature in Health Science, Scientific Electronic Library Online and Virtual Health Library. Results: Methemoglobinemia is a pathology characterized by the presence of high concentrations of methemoglobin (MetHb) in the blood. This is an oxidized form of hemoglobin, very greedy for oxygen, which is unable to transfer it to the tissues. It is a rare entity, with low diagnostic suspicion and in several multicenter studies, dapsone has been the main cause of drug-induced methemoglobin. The case reports a young patient using Polychemotherapy (MDT) with dapsone, rifampicin and clofazimine to treat multibacillary leprosy. She reported dyspnea after taking the medication on the 14th day of use and looked for assitance at the service. Other pathologies with laboratory and imaging tests, such as TEP and COVID-19, were excluded and contact was made with the Toxicological Information and Assistance Center of the State of Espírito Santo (Ciatox), where treatment with intravenous methylene blue was advised. After 40 minutes of administering the drug, the patient showed clinical improvement in dyspnea, as well as in pulse oximetry, evidently. Final considerations: The information obtained in this study will be able to expand the scientific community's knowledge about this pathology, offering better management of these neoplasia and contributing to the benefit of the patient.