Renal disease in Down syndrome: autopsy study with emphasis on glomerular lesions.

A range of renal diseases have been previously described in patients with Down syndrome. With increased survival, it appears that a growing number of these patients present with chronic renal failure. Definition of underlying causes of renal failure could potentially lead to prevention of progressive renal dysfunction in this population. We report two index cases of teenaged Down patients who presented with proteinuria and focal segmental glomerulosclerosis with hyalinosis, not previously described in this population. In addition, autopsy files were reviewed at the Johns Hopkins Hospital to assess renal and especially glomerular pathology in Down patients. Additional cases, including acute glomerulonephritis with early crescents and vasculitis, minimal change disease, and membranous nephropathy, were identified; the latter two diseases had not been previously reported in patients with Down syndrome. Semiquantitative studies on glomerular changes in all cases examined through autopsy also were performed. The only pathological finding that was significantly more common in the Down syndrome group, compared with age-matched cases from the autopsy files, was cystic dilation of Bowman's space. Histological findings described as increased in the Down population in previously published autopsy studies were also present in the control population, highlighting the need to adequately control such studies. The cases of acquired glomerular disease reported here were seen largely after the first decade of life. Monitoring of Down patients for renal and especially glomerular disease should be done regularly as patients age into the second and third decades.