Subclinical kidney injury before and 1 year after bariatric surgery among adolescents with severe obesity

Obesity (Silver Spring). 2015 Jun;23(6):1234-8. doi: 10.1002/oby.21070. Epub 2015 May 9.


Objective: To assess subclinical kidney injury in adolescents with severe obesity by measuring biomarkers of early kidney disease and to assess changes in the levels of these biomarkers following bariatric procedures.

Methods: Twenty-two adolescents undergoing bariatric surgery with no microalbuminuria and normal kidney function were selected. Urinary NGAL, IL-18, and KIM-1 were measured at baseline, 6 and 12 months postoperatively. Biomarker levels were compared to 44 age-gender-matched lean controls.

Results: Subjects with obesity had a mean baseline BMI of 48 kg/m(2) that decreased by 34% at 1-year follow-up. Urine NGAL, IL-18, and KIM-1 were significantly elevated in subjects with obesity compared to lean controls at baseline. The obese cohort had a further significant increase in NGAL and KIM-1 at 6 months, followed by decline at 1 year. The overall change in levels of all three biomarkers through 1 year after surgery, however, was not significant compared to baseline.

Conclusions: Adolescent severe obesity is associated with increased urinary excretion of novel biomarkers of kidney injury, despite no microalbuminuria or decreased kidney function. This subclinical kidney injury persists 1 year after significant weight loss induced by bariatric surgery, suggesting that close, long-term follow-up of kidney status is warranted in these adolescents.

Trial registration: NCT00474318.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acute Kidney Injury / etiology*
  • Acute Kidney Injury / surgery
  • Acute-Phase Proteins / urine*
  • Adolescent
  • Bariatric Surgery / adverse effects
  • Biomarkers / blood
  • Female
  • Hepatitis A Virus Cellular Receptor 1
  • Humans
  • Interleukin-18 / urine*
  • Lipocalin-2
  • Lipocalins / urine*
  • Male
  • Membrane Glycoproteins / urine*
  • Obesity, Morbid / metabolism*
  • Obesity, Morbid / surgery
  • Pediatric Obesity / metabolism*
  • Pediatric Obesity / surgery
  • Proto-Oncogene Proteins / urine*
  • Receptors, Virus
  • Statistics, Nonparametric


  • Acute-Phase Proteins
  • Biomarkers
  • HAVCR1 protein, human
  • Hepatitis A Virus Cellular Receptor 1
  • Interleukin-18
  • LCN2 protein, human
  • Lipocalin-2
  • Lipocalins
  • Membrane Glycoproteins
  • Proto-Oncogene Proteins
  • Receptors, Virus

Associated data