title: Significance of serum IgA levels and serum IgA/C3 ratio in diagnostic analysis of patients with IgA nephropathy.
abstract: Diagnostic analysis of clinical markers including serum IgA levels and serum IgA/C3 ratio in patients with IgA nephropathy is described. One hundred patients with IgA nephropathy (IgA nephropathy group) and 100 patients with other primary glomerular diseases (non-IgA nephropathy group) were examined. The analysis was performed to distinguish between these two groups using four clinical markers: 1) more than five red blood cells in urinary sediments, 2) persistent proteinuria (urinary protein of more than 0.3 g/day), 3) serum IgA levels of more than 315 mg/dl, and 4) a serum IgA/C3 ratio of more than 3.01. Patients with three or four clinical markers were easily diagnosed as having IgA nephropathy in this study. Furthermore, there was a significant difference in these clinical markers between the good prognosis and relatively good prognosis groups (Groups I and II) and the relatively poor prognosis and poor prognosis groups (Groups III and IV) of IgA nephropathy patients. It appears that the presence of microscopic hematuria and/or persistent proteinuria, high serum IgA levels, and the serum IgA/C3 ratio are useful for distinguishing IgA nephropathy from other primary renal diseases. It is postulated that these clinical markers are also useful for diagnosis of IgA nephropathy without renal biopsy.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Juntendo University School of Medicine, Tokyo, japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Maeda
authors.forename: Tomohito
authors.initials: T
authors.lastname: Gohda
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Funabiki
authors.forename: Satoshi
authors.initials: S
authors.lastname: Horikoshi
authors.forename: Isao
authors.initials: I
authors.lastname: Shirato
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tomino
mesh_terms: D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood* / Q000652:urine; D019411:Clinical Laboratory Techniques; D003176:Complement C3 / Q000032:analysis*; D004912:Erythrocytes; D005922:Glomerulonephritis, IGA / Q000097:blood* / Q000145:classification / Q000150:complications / Q000652:urine; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D007678:Kidney Glomerulus / Q000378:metabolism; D016017:Odds Ratio; D011379:Prognosis; D011507:Proteinuria / Q000209:etiology / Q000652:urine; D012016:Reference Values; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D003176:Complement C3; D007070:Immunoglobulin A