Epidemiology of renal disease in children in the region of southern Croatia: a 10-year review of regional renal biopsy databases.

BACKGROUND: Epidemiological data on some renal diseases in children are available from world national registries of renal biopsies. However, there is no publislhed study of biopsy-proven childhood glomerulonephritis in Croatia. This report is the first review of pathohistological data covering a pediatric population over a 10-year period in the Croatian region of Dalmatia.

MATERIAL/METHODS: A retrospective study was done on all renal biopsies from 65 children under 18 years of age received by the Clinical Hospital Split between 1995 and 2005. The histopathological findings were reviewed to determine the pattern of biopsy-proven glomerulonephritis. Indications for renal biopsy and clinico-pathological correlations were studied. Data on serum creatinine concentration, 24-h proteinuria, hematuria, clinical diagnosis, pathohistological diagnosis, and post-biopsy complications were collected.

RESULTS: The main indications for biopsy were nephrotic syndrome (41.5%), hematuria with proteinuria (23.1%), and isolated hematuria (12.3%). The most frequent renal diseases in decreasing order were mesangioproliferative glomerulonephritis (27.7%), IgA nephropathy (13.8%), and Henoch-Schönlein nephritis (10.8%). Tubulointerstitial nephritis, focal segmental glomerulosclerosis, and endoproliferative glomerulonephritis each accounted for 6.2%. Alport syndrome, fibrillary glomerulonephritis, and minimal change diseases were each found in 4.6% of cases. Other forms of glomerulonephritis were rarely found.

CONCLUSIONS: The present data represent the basis for a future Croatian Registry of Renal Biopsies and are an important contribution to the epidemiology of renal diseases in south-eastern Europe. Three cases of fibrillary glomerulonephritis in children with steroid-dependent nephrotic syndrome, not reported in other countries' registries, were also found. The importance of ultrastructural analysis of biopsy specimens is emphasized.