We have studied the incidence of renal involvement, the severity and the clinical course of nephropathy in 83 children, 47 males and 36 females, aged from 2 to 13 years, who were under observation for SSH at the II Pediatric Clinic, Florence University. In 72.3% of cases, we have not observed any sign of renal involvement, at least within 6 months of onset of the syndrome. In 16.3% we have observed persistent urinary abnormalities: these findings have returned to normal within 1 year in 13 children and within 3 years in one child. In 10.8% of cases, a nephropathy has appeared, in all of the cases within 3 months of onset. Only one case has developed renal failure 5 years after onset. We can conclude that a good correlation exists between clinical manifestations of this disease and histopathologic changes; that therapy is of little value in modifying the clinical course; that renal failure is a rare occurrence.