Significance of levels of circulating IgA-class immune complex in discriminant analysis of patients with IgA nephropathy before renal biopsy.
Discriminant analysis of clinical markers including circulating IgA-class immune complex (IgA-CIC) before renal biopsy in patients with IgA nephropathy is described. Fifty-six patients with IgA nephropathy (IgA nephropathy group) and 54 patients with other primary chronic glomerulonephritis (non-IgA nephropathy group) were examined. Discriminant analysis was applied to separate these two groups by using 21 clinical markers including levels of IgA-CIC. The levels of IgA-CIC in sera were measured by a solid-phase anti-C3 Facb enzyme immunoassay (EIA). Among these clinical markers, the levels of serum IgA, IgA-CIC and creatinine, and the degree of microhematuria in the IgA nephropathy group were significantly higher than those in the non-IgA nephropathy group. Contributions of IgA and IgA-CIC to the classification were very high and both had almost the same effect. The correct classification rate was 80.00% using five clinical markers: serum IgA, microhematuria, IgA-CIC, serum creatinine, and blood urea nitrogen. It was shown that the levels of serum IgA and IgA-CIC were major markers for the clinical diagnosis of patients with IgA nephropathy. It was concluded that discriminant analysis before renal biopsy was useful for the diagnosis of IgA nephropathy.
Yagame
M
M
Department of Internal Medicine, School of Medicine, Tokai University, Kanagawa-ken, Japan.
Suzuki
D
D
Watanabe
K
K
Nakao
E
E
Eguchi
K
K
Miyazaki
M
M
Matsumoto
Y
Y
Yano
N
N
Kuramoto
T
T
Sakai
H
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D000936:Antigen-Antibody Complex / Q000032:analysis*; D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood; D005260:Female; D005922:Glomerulonephritis, IGA / Q000175:diagnosis*; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis*; D007668:Kidney / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D013223:Statistics as Topic
D000936:Antigen-Antibody Complex; D015415:Biomarkers; D007070:Immunoglobulin A; D003404:Creatinine