Résumé
Objective:To compare the performance of chemiluminescent microparticle immunoassay ( CMIA) and enzyme-linked immunosorbent assay ( ELISA) for the determination of Anti-PR3 and Anti-MPO.Methods:Concentration of Anti-PR3 and Anti-MPO in serum samples from 166 patients with autoimmune diseases and 50 healthy donors were determined by using CMIA (Method A) and ELISA(Method B),respectively.The results from both assays were analyzed and compared by statistical methods .Results:Method A showed better intra-assay reproducibility and inter-assay reproducibility than Method B for the determination of high ,medium and low levels of control serum .Both methods met the accuracy requirement .The correlation coefficient of Anti-PR3 and Anti-MPO were 0.987 8 and 0.989 6 for Method A and Method B ,respectively.And the Kappa coefficients were 0.897 and 0.882 for Method A and Method B,respectively.Conclusion:The performance of Method A is superior to Method B for the deter-mination of Anti-PR3 and Anti-MPO, which makes Method A to be a potentially better choice for clinical application .
Résumé
La enfermedad de Wegener es una vasculitis de pequeños y medianos vasos asociada a anticuerpos anticitoplasma del neutrófilo (ANCA). Dentro de los órganos blancos, el pulmón se encuentra comprometido en el 85% de los casos. Numerosas entidades deben ser consideradas en el diagnóstico diferencial, entre ellas, la tuberculosis pulmonar. Presentamos el caso de un hombre de 54 años de edad, con diagnóstico en el año 1996 de enfermedad de Wegener, que comienza en agosto de 2007 con expectoración hemoptoica, disnea de esfuerzo progresiva y esputo con baciloscopia BAAR (+), por lo que inicia tratamiento antituberculoso. La baciloscopia no se constata en dos lavados broncoalveolares contemporáneos. Evoluciona con deterioro de la función renal, púrpura palpable y anticuerpos anticitoplasma del neutrófilo patrón citoplasmático (ANCA-c) positivo. Se interpreta reactivación de su enfermedad de base. Inicia tratamiento inmunosupresor y hemodiálisis y suspende tratamiento antituberculoso. Un mes después del alta se reinterna con cuadro similar al previo, con esputo seriado positivo para BAAR.
Wegener's disease is a vasculitis of small and medium-sized vessels associated with anti-neutrophil cytoplasm antibodies (ANCA). Within their target organs the lungs are involved in 85% of cases. Many entities are part of the differential diagnosis, including pulmonary tuberculosis. We present the case of a 54 years old man, diagnosed as Wegener's disease in 1996 which begins in August 2007 with cough, hemoptysis, progressive dyspnea on effort and serial sputum positive for AFB and then starts TB treatment. Subsequent bronchoalveolar fluids resulted negative for AFB. The patient evolved with impaired renal function, palpable purpura and positive anti-neutrophil cytoplasm antibodies cytoplasmic pattern (c-ANCA), interpreted as Wegener's disease relapse. He started hemodialysis and immunosuppressive therapy and tuberculosis treatment was stopped. One month after discharge was readmitted with a similar picture with serial sputum positive for AFB.