Complete Remission from C1q Nephropathy with Disappearance of C1q Deposition after Steroid Therapy / 대한내과학회지

ABSTRACT

C1q nephropathy is a rare glomerular disease, defined by characteristic mesangial C1q immune deposition seen in immunofluorescence microscopy with no serological evidence of systemic lupus erythematosus. C1q nephropathy can be diagnosed with a subsequent biopsy, as with IgA nephropathy. There are some cases with an initial diagnosis of hematuria and proteinuria with minimal disease changes, focal segmental glomerulonephritis, and mesangial proliferative glomerulonephritis, but lacking C1q nephropathy, in which C1q deposition on immunofluorescence subsequently develops. We report a case that was diagnosed as diffuse mesangial proliferative glomerulonephritis, but a subsequent biopsy showed C1q nephropathy, with C1q deposition in both immunohistochemistry and electron microscopy (EM). We treated the C1q nephropathy with methylprednisolone and confirmed the disappearance of C1q depositions by both immunohistochemistry and EM in a follow-up biopsy.