title: Fluctuation of serum C3 levels reflects disease activity and metabolic background in patients with IgA nephropathy.
abstract: BACKGROUND
  We focused on the fluctuations of serum C3 levels throughout the clinical course of patients and investigated the relationship between these fluctuations and clinical findings.
  
  
  METHODS
  IgA nephropathy patients (n = 122) were enrolled in the present study. Serum C3 and other clinical markers were compared at the time of renal biopsy and at last follow-up (6.67 ± 2.07 years). Patients were divided into 3 groups based on serum C3 levels: Group I with first C3 levels below the mean -1 SD, which turned into an increase at last observation; group II with first C3 levels more than the mean +1 SD, which turned into a decrease at last observation; and group III, with first C3 levels more than the mean +1 SD, which turned into an increase at last observation. First and last levels of clinical markers were compared among the 3 groups.
  
  
  RESULTS
  Serum C3 levels of the patients whose renal symptoms, including hematuria, proteinuria and estimated glomerular filtration rate (eGFR), were improved, were significantly increased at last observation (p<0.05, p<0.01, p<0.01, respectively). Age, total cholesterol and triglyceride levels in group III were significantly higher than those in group I. Group II showed a significant reduction of urinary protein. Groups I and II maintained renal function, but group III showed a significant deterioration of renal function.
  
  
  CONCLUSIONS
  The levels and fluctuations of serum C3 might reflect the disease activity and metabolic alteration in patients with IgA nephropathy.
authors: Division of Nephrology, Department of Internal Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan.
authors: Hiyori
authors: H
authors: Suzuki
authors: Isao
authors: I
authors: Ohsawa
authors: Fumiko
authors: F
authors: Kodama
authors: Kazutaka
authors: K
authors: Nakayama
authors: Atsuko
authors: A
authors: Ohtani
authors: Kisara
authors: K
authors: Onda
authors: Seiji
authors: S
authors: Nagamachi
authors: Atsushi
authors: A
authors: Kurusu
authors: Yusuke
authors: Y
authors: Suzuki
authors: Hiroyuki
authors: H
authors: Ohi
authors: Satoshi
authors: S
authors: Horikoshi
authors: Yasuhiko
authors: Y
authors: Tomino
mesh_terms: D000328:Adult; D003176:Complement C3 / Q000032:analysis*; D005260:Female; D005500:Follow-Up Studies; D005922:Glomerulonephritis, IGA / Q000097:blood* / Q000378:metabolism; D006801:Humans; D008297:Male
chemical_list: D003176:Complement C3