C1q nephropathy: a pediatric clinicopathologic study.
We report on 15 children with proteinuria, at the nephrotic level in the majority of cases, who had no histologic glomerular alterations (eight cases), or focal and segmental glomerular scarring with (three cases) or without (four cases) mesangial proliferation. In all cases, immunofluorescence (IF) microscopy showed prominent mesangial C1q deposits with variable amounts of immunoglobulins. Ultrastructurally, most had conspicuous mesangial electron-dense deposits. Cases with no glomerular histologic alterations were histologically indistinguishable from minimal change disease (MCD), yet they uniformly had an unsatisfactory response to oral prednisone. Thus, the presence of immune deposits with a prominent C1q contribution identifies a group of cases that respond poorly to steroids and that, if light microscopy is considered in isolation, might otherwise be designated MCD.
Department of Pathology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157-1072.
S S
SS
Iskandar
M C
MC
Browning
W B
WB
Lorentz
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015922:Complement C1q / Q000032:analysis*; D003176:Complement C3 / Q000032:analysis; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007674:Kidney Diseases / Q000276:immunology / Q000473:pathology*; D007678:Kidney Glomerulus / Q000276:immunology / Q000473:pathology; D008297:Male
D003176:Complement C3; D007136:Immunoglobulins; D015922:Complement C1q