Brazilian Journal of Nephrology (Mar 2010)
Um índice clínico preditor de sobrevida renal A clinical predictor index for renal survival
Abstract
INTRODUÇÃO: Um índice capaz de antecipar a progressão da doença renal independente dos achados histológicos seria de inestimável valor para a indicação da biópsia renal. OBJETIVO: Avaliar se um índice clínico baseado na ecogenicidade cortical renal, na relação diâmetro longitudinal do rim/altura do indivíduo (KL/H) e na creatinina sérica pode predizer a sobrevida renal. MÉTODOS: As lesões crônicas (obsolescência glomerular, esclerose segmentar e focal, atrofia tubular e fibrose intersticial) e agudas (proliferação mesangial, permeação leucocitária, necrose fibrinoide e crescentes e infiltrado intersticial) das biópsias de 154 pacientes foram graduadas e somadas para geração de índices. Um índice clínico de cronicidade foi criado pela soma da gradação da ecogenicidade cortical relativa a do fígado ou baço, dos níveis de creatinina sérica e da relação KL/H. O desfecho do estudo foi a necessidade de iniciar diálise. RESULTADOS: Os maiores graus do índice clínico de cronicidade e do índice crônico de biópsia foram associados com sobrevida renal mais curta. Dos seis pacientes com creatinina sérica > 2,5 mg/dL, maior ecogenicidade cortical e KL/H INTRODUCTION: A clinical index that discriminates disease progression independent of histopathologic features may be valuable in the best timing of biopsy. OBJECTIVE: This study addresses the question if a clinical index based on cortical echogenicity, renal length to body height ratio (KL/H), and serum creatinine levels predicts renal survival. METHODS: The study enrolled 154 patients. Biopsy specimens were graded for chronic (glomerular obsolescence, segmental glomerular sclerosis, tubular atrophy and interstitial fibrosis) and acute (mesangial proliferation, leucocyte permeation, crescent and fibrinoid necrosis and interstital infiltrate) index by the sum of scored lesions. A chronic clinical index was created by the sum of scored cortical echogenicity relative to liver or spleen, creatinine serum levels and KL/H. The study end point was start on dialisis. RESULTS: Higher grade of chronic clinical and biopsy indices were associated with poorer long-term renal survival. Five out of six patients with serum creatinine levels > 2.5mg/dL, highest cortical echogenicity and KL/H < 0.60, before biopsy, startet on dialysis and one increased creatinine levels up to 4.5 mg/dL. The chronic clinical index correlates well with chronic biopsy index. CONCLUSIONS: The chronic clinical index could be useful to predict a clinical setting in which a renal biopsy will show advanced chronic and irreversible lesion. In patients with highest grade of clinical parameters renal biopsy can be obviate. As a chronicity of illness index for groups of patients with renal medical diseases, the system could be useful in outcome comparisons and evaluation of therapeutic efficacy.
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