Recurrent focal segmental glomerulosclerosis. A pathological study of the early lesion.

We describe the early lesion of focal segmental glomerulosclerosis (FSGS) as it appeared in 2 cases of recurrent FSGS with early transplant nephrectomies (approximately 2 months) due to uncontrollable nephrotic syndrome. A quantitative evaluation showed that these lesions were present more often in the glomeruli of the juxtamedullary cortex. Epithelial cell proliferation and detachment and foam cells were seen frequently and were considered the hallmarks of the early lesion of FSGS. Hyaline deposits are secondary late phenomena. We suggest that the glomerular foam cells in FSGS are mesangial in origin.