The natural history of focal segmental glomerulosclerosis with and without mesangial hypercellularity in children.

The clinical courses and biopsy findings of twenty-four children with focal segmental glomerulosclerosis (FSG) were reviewed retrospectively to determine whether the presence of significant mesangial accentuation and proliferation (MAP) has prognostic implications. At the latest assessment, 10 of 13 patients with significant mesangial involveme,t (MAP [+]) had glomerular filtration rates less than or equal to 90 ml/min/1.73 m2, with four in renal failure. In contrast, all of eleven children with no significant mesangial involvement (MAP [-]) maintain glomerular filtration rates greater than 90 ml/min/1.73 m2, (P less than 0.001). Of no prognostic importance were: age at onset of disease, type of onset, or presence or absence of hematuria. The preponderance of males in the MAP (+) group was a statistically significant difference (P less than 0.001). The two groups did not differ in regard to either the type of clinical course or the length of the period of observation, and there was no obvious effect of therapy in either group of patients. Immunofluorescence data were of no value in differentiating between the two groups. Our results imply that FSG with significant mesangial accentuation and proliferation is a unique glomerular disease of childhood, with a clinical course characterized by rapid progression to renal insufficiency. FSG without mesangial involvement, on the other hand, appears to have an excellent prognosis over long periods of time. At present, these two diseases can be differentiated only by renal biopsy.