Evaluation of diagnostic criteria for analgesic nephropathy in patients with end-stage renal failure: results of the ANNE study

Abstract

It was found that in Belgium, renal imaging techniques, demonstrating a decreased renal mass of both kidneys combined with either bumpy contours or papillary calcifications, were the only methods to reliably diagnose analgesic nephropathy (AN) in patients with end-stage renal failure. However, these criteria were selected in an area with a high prevalence of this disease (15.6% of the dialysis population at December 1990). To evaluate the criteria selected to diagnose AN in populations with lower or unknown prevalences of AN, the Analgesic Nephropathy Network of Europe (ANNE) was formed, consisting of 23 dialysis units from 14 European countries and Brazil. During 1991-1992, 598 new patients with equivocal diagnosis of renal disease (excluding biopsy-proven glomerulonephritis, polycystic disease, diabetic nephropathy and other systemic diseases) and who began renal replacement therapy in the ANNE centres were evaluated by a short questionnaire and two renal imaging techniques: sonography and either tomography or computed tomography (CT) scan. A comparison of 82 abusers (daily use of analgesic mixtures for at least 5 years) and 495 controls corroborated the excellent diagnostic performance of the renal imaging techniques for AN. We recommend the use of these renal imaging criteria in all patients without a clear renal diagnosis in order to obtain a more reliable insight into the magnitude of the AN problem in different countries.