title: Effect of treatment on urinary kidney injury molecule-1 in IgA nephropathy.
abstract: BACKGROUND
  Kidney injury molecule-1 (KIM-1) is a biomarker useful for detecting early tubular damage and has been recently reported as a useful marker for evaluating kidney injury in IgA nephropathy (IgAN). We therefore investigated whether treatment decreases urinary KIM-1 excretion in IgAN.
  
  
  METHODS
  We prospectively enrolled 37 patients with biopsy-proven IgAN. Urinary KIM-1 was assessed before and after treatment, which included low salt diet, blood pressure control, pharmacotherapy with angiotensin receptor blockers and/or angiotensin converting enzyme inhibitors, and immunosuppressive agents as necessary. The median treatment duration was 24 months.
  
  
  RESULTS
  Urinary KIM-1/creatinine (Cr) was significantly decreased in patients with IgAN after treatment compared to baseline (P < 0.0001, 1.16 [0.51-1.83] vs 0.26 [0.12-0.65] ng/mg). There was a decrease in the amount of proteinuria after treatment, but it was not statistically significant (P = 0.052, 748.1 [405-1569.7] vs 569.2 [252.2-1114] g/d). Estimated glomerular filtration rate (eGFR) did not change with treatment (P = 0.599, 79.28 ± 30.56 vs 80.98 ± 32.37 ml/min/1.73 m2). Urinary KIM-1 was not correlated with proteinuria baseline or follow up (pre-: R = - 0.100, P = 0.577, post-: R = 0.001, P = 0.993). In patients with higher baseline urinary KIM-1, both urinary KIM-1 level and proteinuria were significantly decreased following treatment.
  
  
  CONCLUSIONS
  Treatment decreases urinary KIM-1/Cr in patients with IgAN. It also reduces proteinuria in patients with higher baseline urinary KIM-1. These results suggest a potential role for urinary KIM-1 as a biomarker for predicting treatment response in IgAN, however, further study is needed to verify this.
authors.forename: Mi Seon
authors.initials: MS
authors.lastname: Seo
authors.forename: Moo Yong
authors.initials: MY
authors.lastname: Park
authors.forename: Soo Jeong
authors.initials: SJ
authors.lastname: Choi
authors.forename: Jin Seok
authors.initials: JS
authors.lastname: Jeon
authors.forename: Hyunjin
authors.initials: H
authors.lastname: Noh
authors.forename: Jin Kuk
authors.initials: JK
authors.lastname: Kim
authors.forename: Dong Cheol
authors.initials: DC
authors.lastname: Han
authors.forename: Seung Duk
authors.initials: SD
authors.lastname: Hwang
authors.forename: So Young
authors.initials: SY
authors.lastname: Jin
authors.forename: Soon Hyo
authors.initials: SH
authors.lastname: Kwon
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D005922:Glomerulonephritis, IGA / Q000175:diagnosis* / Q000628:therapy / Q000652:urine*; D000072596:Hepatitis A Virus Cellular Receptor 1; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000652:urine*; D008875:Middle Aged; D011446:Prospective Studies; D011991:Receptors, Virus; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; C491143:HAVCR1 protein, human; D000072596:Hepatitis A Virus Cellular Receptor 1; D008562:Membrane Glycoproteins; D011991:Receptors, Virus