| Popis: |
Renal involvement in antineutrophil cytoplasmic antibodies (ANCA) associated vasculitis is frequent and, if there is no response to treatment, progression to end-stage renal disease is fast, leading to increased mortality. We evaluated several factors (clinical, analytical and histological) as predictors of progression to dialysis-dependent stage 5 chronic kidney disease within 2 years after diagnosis of kidney biopsy-proven ANCA-associated vasculitis (outcome), between 1997 and 2010. Twenty-seven patients (16 men, mean age 58 years) met the inclusion criteria. The most common extra-renal manifestations were haematological (93%) and systemic symptoms (70%). At the time of biopsy, mean creatinine and proteinuria were 5.11 �± 2.5mg/dL and 2.36 �± 2.1g/day, respectively. The majority of patients (81%) had ANCA against myeloperoxidase. The induction therapy was with corticosteroids and cyclophosphamide in 71%; 40% received maintenance treatment with azathioprine. At 2 years, 12 patients (27.44%) began renal replacement therapy (RRT). Only a higher serum creatinine at diagnosis, within the clinical and analytical variables analysed, was a significant predictor of renal outcome (odds ratio (OR) = 1.73, p = 0.046) in a logistic regression model adjusted for age and sex. We developed a histological index (0 to 1 point considering the absence or presence of: < 30% of normal glomeruli, > 50% cellular crescents, > 30% glomerulosclerosis, moderate-severe tubular atrophy and interstitial infiltrate), which was associated with renal prognosis at 2 years (OR = 2.07, p = 0.043). This means that for each 1-point increase in the created index the likelihood of needing to RRT to 2 years rises 2.1 times. We then stratified the histological variables into glomerular and tubulointerstitial findings. We found that only the glomerular findings (OR = 4.99, p = 0.049) were independent predictors of the outcome, with glomerulosclerosis (OR = 16.7, p = 0.04) being the most significant. We concluded that baseline serum creatinine and glomerular histological findings were independent predictors of the renal prognosis and may prove helpful in the management of these patients. O envolvimento renal nas vasculites associadas aos anticorpos anticitoplasma de neutrofilos (ANCA) e frequente e, na ausencia de resposta ao tratamento, evoluem rapidamente para doenca renal terminal, com aumento da mortalidade. Avaliamos varios fatores (clinicos, analiticos e histologicos) como preditores da evolucao para Doenca Renal Cronica Estadio 5 com necessidade de dialise aos 2 anos em doentes com envolvimento renal por vasculite ANCA confirmado por biopsia (“outcome”) entre 1997 e 2010. Vinte e sete doentes (16 do sexo masculino, idade media de 58 anos) obedeceram aos criterios de inclusao. As manifestações extra-renais mais frequentes foram hematologicas (93%) e sintomas sistemicos (70%). A data da biopsia a creatinina e a proteinuria media eram 5,11 �± 2,5mg/dL e 2,36 ± 2,1g/dia, respectivamente. A maioria dos doentes (81%) tinha ANCA contra mieloperoxidase. A terapeutica de inducao foi em 71% com corticoides e ciclofosfamida; 40% receberam tratamento de manutencao com azatioprina. Aos 2 anos, 12 (27,44%) iniciaram tecnicas de substituicao renal (TSR). Apenas a creatinina mais elevada a apresentacao, dentro das variaveis clinicas e analiticas, foi preditor significativo de “outcome” (odds ratio (OR) = 1,73; p = 0,046), num modelo de regressao logistica ajustado para a idade e sexo. Desenvolvemos um indice histológico (0 ou 1 ponto considerando a presenca de: < 30% de glomerulos normais, > 50% crescentes celulares, > 30% glomerulosclerose, infiltrado intersticial e atrofia tubular moderados-graves), que se associava com o prognostico renal aos 2 anos (OR = 2,07, p = 0,043). Isto significa que, por cada aumento de 1 ponto no indice criado, a probabilidade de necessidade de TSR aos 2 anos torna-se 2,1 vezes maior. Depois estratificamos as variaveis histologicas em achados glomerulares e tubulointersticiais: verificamos que apenas os primeiros eram preditivos do prognostico (OR = 4,99, p =0,049), sendo a glomerulosclerose a mais significativa (OR = 16,07, p = 0,04). Concluiu-se que a creatinina e os achados histologicos glomerulares sao preditores independentes do prognostico renal, podendo mostrar-se uteis no acompanhamento destes doentes. |
