title: Absence of mesangial C1q deposition is associated with resolution of proteinuria and hematuria after tonsillectomy plus steroid pulse therapy for immunoglobulin a nephropathy.
abstract: OBJECTIVE
  Deposition of C1q occurs in 0 to 45% of patients with IgAN. In order to identify whether mesangial C1q deposition in IgAN is a novel marker for the response to tonsillectomy plus steroid pulse therapy (TSP), we studied the association between mesangial C1q deposition in IgAN and the remission rate after TSP therapy for IgAN.
  
  
  METHODS
  We conducted a retrospective cohort study at a single Japanese center. We analyzed data on 110 patients diagnosed with IgA nephropathy who received TSP between January 2003 and December 2012. Positive C1q findings were defined as diffuse mesangial C1q deposition. The study outcome was the resolution of abnormal urinary findings and was defined as negative proteinuria and negative occult blood 1 year after steroid pulse therapy.
  
  
  RESULTS
  In all enrolled cases, 69 patients (62.7%) went into remission. Ten out of 24 (41.7%) C1q-positive patients experienced remission, and 59 out of 86 (68.6%) C1q-negative patients experienced remission. Multiple logistic regression model analysis showed that the absence of C1q deposition increased the odds ratio for remission (odds ratio 4.41; 95% confidence interval 1.33-15.75, p = 0.017).
  
  
  CONCLUSIONS
  These results suggest that the absence of diffuse C1q deposition in the mesangial area of the glomerulus in patients with IgA nephropathy is a positive predictive sign for a response to TSP and is associated with the resolution of urinary abnormalities 1 year after TSP.
authors.affiliation: Division of Nephrology, Showa University Fujigaoka Hospital, Yokohama, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nishiwaki
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Yoshikuni
authors.initials: Y
authors.lastname: Nagayama
authors.forename: Nobuharu
authors.initials: N
authors.lastname: Kaneshima
authors.forename: Mamiko
authors.initials: M
authors.lastname: Takayasu
authors.forename: Makoto
authors.initials: M
authors.lastname: Hirose
authors.forename: Daisuke
authors.initials: D
authors.lastname: Komukai
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Inoue
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Koiwa
authors.forename: Ashio
authors.initials: A
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000009:adverse effects / Q000627:therapeutic use; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D015331:Cohort Studies; D015922:Complement C1q / Q000032:analysis / Q000378:metabolism*; D005260:Female; D005920:Glomerular Mesangium / Q000378:metabolism*; D005922:Glomerulonephritis, IGA / Q000188:drug therapy* / Q000601:surgery*; D006417:Hematuria / Q000209:etiology / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D011183:Postoperative Complications / Q000188:drug therapy* / Q000378:metabolism*; D011237:Predictive Value of Tests; D011239:Prednisolone / Q000009:adverse effects / Q000627:therapeutic use; D011507:Proteinuria / Q000209:etiology / Q000378:metabolism*; D012189:Retrospective Studies; D013256:Steroids / Q000009:adverse effects* / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000893:Anti-Inflammatory Agents; D015415:Biomarkers; D013256:Steroids; D015922:Complement C1q; D011239:Prednisolone