How many kinds of FSGS are there, and what are their individual prognoses?
Focal segmental glomerulosclerosis (FSGS) has many diverse pathologic presentations. In an important new study, Thomas et al. now provide an excellent clinical correlation between the pathologic description and the clinical outcome of patients with FSGS. They studied forms of FSGS previously grouped into several types: cellular, collapsing, tip lesion, perihilar, and not readily classifiable. Collapsing FSGS was more likely to affect younger and black patients. Black race was uncommon in the tip variant. Patients who had collapsing and tip variants had higher proteinuria and lower serum albumin than patients with the other types of FSGS. Better renal function and less severe tubulointerstitial injury at histology were observed in patients with the tip variant. These patients more often achieved complete remission and were more likely to receive steroids than the patients with other types of FSGS. After a median follow-up of 1.8 years, 23% of all patients were on dialysis, and 28% had r
