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Toxicidad de la Dapsona en la Policondritis Recidivante: Metahemoglobinemia y Anemia Hemolítica Concomitante
José Nuno Magalhães1, Ana Monteiro2
1Medicina, Unidade Local de Saúde de Santo António, Porto, PRT.
Cureus
|February 23, 2026
Resumen
La dapsona, utilizada para la policondritis recidivante, puede causar metahemoglobinemia y hemólisis. Un paciente experimentó estos problemas, diagnosticados mediante un "gap de saturación", y mejoró tras la administración de azul de metileno y la retirada de la dapsona.
Área de la Ciencia:
- Reumatología; Hematología; Farmacología
Sus antecedentes:
- La policondritis recidivante (PC) es un trastorno raro mediado por el sistema inmunitario que afecta al cartílago.; La dapsona es un agente que ahorra esteroides para la PC, pero conlleva riesgos de metahemoglobinemia y hemólisis.; Los metabolitos oxidativos de la dapsona están implicados en estos efectos adversos.
Objetivo del estudio:
- Informar un caso de metahemoglobinemia y hemólisis oxidativa inducida por dapsona en un paciente con PC.; Destacar la utilidad diagnóstica del "gap de saturación" en la identificación de estas afecciones.; Enfatizar la importancia de considerar la toxicidad de la dapsona en pacientes con hipoxemia o anemia inexplicables.
Principales métodos:
- Reporte de caso de un hombre de 70 años con PC con diagnóstico confirmado por biopsia.; Presentación clínica de disnea progresiva y cianosis bajo tratamiento con dapsona.; Estudio diagnóstico que incluye cooximetría y análisis de frotis de sangre periférica.
Principales resultados:
- El paciente desarrolló metahemoglobinemia, evidenciada por un "gap de saturación" (oximetría de pulso baja con tensión de oxígeno arterial preservada).; La administración de azul de metileno condujo a una rápida mejoría clínica.; La anemia consistente con hemólisis oxidativa también se resolvió después de la interrupción de la dapsona.
Conclusiones:
- La dapsona puede inducir metahemoglobinemia y hemólisis oxidativa potencialmente mortales en pacientes con PC.; El "gap de saturación" es una pista diagnóstica crucial para la dishemoglobinemia relacionada con la dapsona.; El reconocimiento temprano y la interrupción de la dapsona son esenciales para la recuperación del paciente y la prevención de recurrencias.
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