Patterns of renal disease in Cape Town South Africa: a 10-year review of a single-centre renal biopsy database

Background. The patterns of glomerular diseases have been widely reported from different regional and national biopsy registries worldwide. However, there are scant studies on the epidemiology of biopsy-proven renal disease, particularly glomerular diseases in sub-Saharan Africa. Methods. We retrospectively analysed the reports of 1284 native renal biopsies, reviewed by the same pathologist and performed at the Groote Schuur Hospital in Cape Town from 1 January 2000 to 31 December 2009. Results. The mean age of all the patients biopsied was 36.8 +/- 14.0 years with 61.8% of the patients being under 40 years of age. There was a preponderance of females (54.8%). There were more coloured patients (53.7%) than blacks (42.2%) or whites (3.9%). The frequencies of clinical indications for a renal biopsy were nephrotic range proteinuria (52.5%), acute renal failure (21.3%), asymptomatic urinary abnormalities (13.6%), chronic renal failure (6.4%), acute nephritic syndrome (5.8%) and haematuria (0.3%). The frequencies of the primary glomerulonephritis (GN) include mesangiocapillary GN (20.4%), mesangial proliferative GN (19.2%), membranous GN (18.5%), crescentic and necrotizing GN (11.4%), focal and segmental glomerulosclerosis (10.5%), post-infectious GN (8.2%), minimal change disease (6.0%) and IgA nephropathy (5.8%). Lupus nephritis was the most frequent secondary glomerular disease (39.0%) and was also the most frequent cause of the nephrotic range proteinuria (17.2%). HIV-associated nephropathy increased from 6.6% in 2000 to 25.7% in 2009 (P < 0.0001). Conclusion. Our data are an important contribution to the epidemiology of renal disease in Africa. We hope that this will form the basis for developing a renal biopsy registry in South Africa and across the continent.