Prognosis, treatment and outcome of childhood mesangiocapillary (membranoproliferative) glomerulonephritis.

BACKGROUND: Prognostic factors and outcome are incompletely known in childhood mesangiocapillary glomerulonephritis (MCGN). This study aimed to correlate renal outcome with clinical and histopathological variables.

METHODS: We conducted a two-centre retrospective analysis of children with MCGN.

RESULTS: Fifty-three children presented at a mean age of 8.8 years (range: 13 months-15 years). They were followed for a median of 3.5 years (range: 0-17 years). Histological classification identified 31 type 1, 14 type 2, two type 3 and six undetermined type. Mean renal survival [time to end-stage renal failure (ESRF)] was projected to be 12.2 years [confidence interval (CI): 9.7-14.6 years]. Five and 10 year renal survival was 92% (CI: 88-100%) and 83% (CI: 74-92%), respectively. Those with nephrotic syndrome at presentation had mean renal survival of 8.9 years (CI: 7.1-10.7 years) vs 13.6 years for those without (CI: 10.8-16.5 years) (P = 0.047). The mean estimated glomerular filtration rate (eGFR) at 1 year in those who progressed to ESRF was 52 vs 98 ml/min/1.73 m2 in those who did not (P < 0.001). Chronic damage scored on the first biopsy in 31 children (one centre) was positively associated with adverse renal outcome at 5 years: <20% was associated with 100% and > or =20% with 71% 5-year renal survival (P = 0.006). In 29 children treated with steroid there was a higher proportion (76%) with reduced eGFR at presentation and a significantly higher incidence of nephrotic syndrome (P = 0.002) and hypertension (P = 0.037). There were no significant differences in outcome eGFR, hypertension or proteinuria.

CONCLUSIONS: Nephrotic syndrome at presentation and subnormal eGFR at 1 year were adverse features. The finding that structural disease at onset predicted poor renal outcome at 5 years has implications for the design of therapeutic trials. Treatment of MCGN was variable and not evidence-based.