RESUMEN
Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and cryoglobulinemic vasculitis (CV) rarely coexist. An 83-year-old woman was admitted with rapidly progressive renal failure, gastrointestinal hemorrhage and purpura with myeloperoxidase (MPO)-ANCA positivity and cryoglobulinemia. Despite intensive immunosuppressive treatment, she died of aspergillus pneumonia. Autopsy revealed necrotizing crescentic glomerulitis in the majority of the glomeruli, accompanied by partially membranoproliferative-like glomerular changes. Immunofluorescence staining revealed the presence of neutrophil extracellular trap (NET) formation in the glomeruli and cutaneous arteries. These pathological findings suggested that MPO-AAV and/or CV caused NET formation, leading to lethal systemic vasculitis.
Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Crioglobulinemia/complicaciones , Crioglobulinemia/patología , Vasculitis Sistémica/complicaciones , Vasculitis Sistémica/patología , Anciano de 80 o más Años , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/inmunología , Autopsia , Trampas Extracelulares/inmunología , Resultado Fatal , Femenino , Tracto Gastrointestinal/patología , Glomerulonefritis/inmunología , Humanos , Riñón/patología , Glomérulos Renales/inmunología , Glomérulos Renales/patología , Peroxidasa/inmunología , Piel/inmunología , Piel/patologíaRESUMEN
Tacrolimus is the most commonly used immunosuppressant. Because of its narrow therapeutic range, it is necessary to frequently monitor its concentration. We report the case of a 25-year-old man who underwent kidney transplantation whose tacrolimus concentrations, as measured by an affinity column-mediated immunoassay, were falsely elevated. As we reduced the dose of tacrolimus, the recipient developed T cell-mediated rejection. Using the same blood samples, an enzyme-multiplied immunoassay technique showed that the patient's levels of tacrolimus were extremely low. A further examination indicated that the false increase in the tacrolimus concentration was likely due to an unknown interfering substance. We administered methylprednisolone and antithymocyte-globulin. The patient's serum creatinine level decreased and remained stable after these treatments.