Prognostic factors in mesangioproliferative glomerulonephritis.

BACKGROUND The aim of our study was to examine patients with mesangioproliferative glomerulonephritis (MPGN), with or without glomerular IgA deposits, and to analyse the effect of different clinical and histopathological variables at the time of biopsy on progression to end-stage renal failure (ESRF) and death. METHODS We retrospectively examined 273 patients who got this diagnosis in Norway from April 1988 to December 1990 after a renal biopsy. All patients were followed for a median duration of 34.8 months (0.8-68 months). RESULTS The mean age at the time of biopsy was 40+/-17 years (range 1.1-79 years). Glomerular IgA deposits were present in 45% of the patients; IgA deposits did not affect prognosis. Three years after the time of biopsy, 7% had developed ESRF (chronic dialysis treatment or kidney transplantation) and 8% had died. By Kaplan-Meier analyses, the following clinical variables indicated progression to ESRF: increased serum creatinine, proteinuria > or =1 g/24 h, systolic blood pressure (BP) > or =160 mmHg, diastolic BP > or =90 mmHg, serum albumin <35 g/l, presence of urinary granular casts and age > or =60 years. Morphological variables indicating progression to ESRF were presence of focal mesangial sclerosis, focal glomerular crescents or necroses, benign nephrosclerosis and increased interstitial score. In the multivariable analysis, the following variables indicated progression to ESRF: increased serum creatinine (P<0.001), decreased serum albumin (P<0.05), increased diastolic BP (P<0.05), low age (P<0.05) and increased interstitial score (P<0.001). CONCLUSIONS It is possible from clinical and histopathological variables to identify low-risk and high-risk patients at the time of biopsy. There is, however, considerable convergence. A major new observation is the finding of young age, decreased serum albumin and the presence of urinary granular casts as important clinical risk factors. Interstitial damage was the most important histopathological predictor of ESRF.