Chronic nephropathy in idiopathic multicentric osteolysis.

A 19-year-old girl having a sporadic form of idiopathic multicentric osteolysis with nephropathy is described. She was first diagnosed as having sporadic carpotarsal osteolysis at the age of 6. Her proteinuria was first detected at 15 years of age and renal biopsy specimens obtained at the same age were compatible with those of focal segmental glomerulosclerosis with interstitial fibrosis and tubular atrophy. Immunofluorescence microscopy revealed negative deposits of Ig G, Ig A and C3 but a trace amount of mesangial Ig M in unsclerosed segments of the glomeruli. Electronmicroscopy showed no specific changes. Renal vascular changes such as proliferation of vascular intima and medial hypertrophy were not demonstrated in the present case. It is our conclusion that focal segmental glomerulosclerosis is part of the spectrum of nephropathy in the sporadic form of idiopathic multicentric osteolysis.