[Clinical and pathologic features of nephropathy with C1q deposits]

To determine the frequency, clinical and morphological features of a nephropathy with C1q deposits in chronic glomerulonephritis adult patients.

296 specimens of kidneys of patients with a chronic glomerulonephritis (CGN) from 2014 for 2018 were analyzed. At the first step, specimens with C1q deposits in glomeruli revealed by immunofluorescent method were chosen. Lupus nephritis and primary membranoproliferative glomerulonephritis were exclusion criteria. At the second step, the retrospective analysis of the clinical characteristics was carried out.

Deposits of C1q in kidneys at 12 of 296 (4.05%) CGN were revealed, m:f ratio 2:1. Average age of the beginning of a disease was 32.1±14.7 years. At a morphological research in 8 membranous nephropathy (MN), in 2 mesangioproliferative glomerulonephritis (MesPGN), in 2 - nephrosclerosis was revealed. Among 12 patients in 5 the disease debuted a nephrotic syndrome, at the others - a proteinuria from 0.5 to 4.0 g/days with the subsequent formation of a nephrotic syndrome. In 5 of 12 patients the disease was characterized by a favor course with preserved kidney function. At 7 patients at the time of inspection decrease in function of kidneys [glomerular filtration rate (eGFR) 31 (30-34) ml/min] was noted. 5 had slow progressing of a renal failure. 2 of 12 progressed to renal failure (eGFR to 19 and 24 ml/min) within a year.

Deposits of C1q in kidney were revealed in 4.05% of biopsy specimens in CGN. The most frequent morphological form was the membranous nephropathy. The clinical course was characterized by a nephrotic syndrome, more than at a half of patients - with renal dysfunction.