title: Measurement of salivary cortisol level for the diagnosis of critical illness-related corticosteroid insufficiency in children.
abstract: OBJECTIVE
  To compare serum total, serum free and salivary cortisol in critically ill children.
  
  
  METHODS
  Prospective observational cohort study.
  
  
  METHODS
  Tertiary pediatric critical care unit at Ronald McDonald Children's Hospital at Loyola University Medical Center.
  
  
  METHODS
  We enrolled 59 patients (4 weeks to 18 years of age) between January 2012 and May 2013. Thirty-four patients were included in the salivary to serum free cortisol correlational analysis.
  
  
  METHODS
  Blood and saliva samples were obtained simultaneously within 24 hours of admission between the hours of 6 AM and 12 PM. Salivary cortisol was tested by liquid chromatography/tandem mass spectrometry, serum free cortisol by liquid chromatography/tandem mass spectrometry followed by equilibrium dialysis, and serum total cortisol by liquid chromatography/tandem mass spectrometry.
  
  
  RESULTS
  Salivary and serum free cortisol values from 34 patients had a correlation coefficient (r) of 0.87 (95% CI, 0.75-0.93; p < 0.0001). The total serum and salivary cortisol values had a correlation coefficient (r) of 0.67 (95% CI, 0.42-0.81; p < 0.0001). The total serum and serum free cortisol values had a correlation coefficient (r) of 0.83 (95% CI, 0.69-0.91; p < 0.0001).
  
  
  CONCLUSIONS
  Serum free and salivary cortisol values correlate in critically ill children. Salivary cortisol can be used as a surrogate for serum free cortisol in critically ill pediatric patients. Salivary cortisol is a cost-effective and less invasive measure of bioavailable cortisol and offers an alternate and accurate method for assessing critical illness-related corticosteroid insufficiency in children.
authors: 1Division of Pediatric Critical Care, Ann and Robert H. Lurie Children's Hospital, Northwestern University, Chicago, IL. 2Clinical Research Office, Stritch School of Medicine, Loyola University Chicago, Maywood, IL. 3Division of Pediatric Endocrinology, Department of Pediatrics, Stritch School of Medicine, Loyola University Medical Center, Maywood, IL. 4Department of Biostatistics and Epidemiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL. 5Department of Pediatrics, Stritch School of Medicine, Loyola University Medical Center, Maywood, IL. 6Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University of Chicago, Maywood, IL. 7Division of Pediatric Critical Care, Department of Pediatrics, Stritch School of Medicine, Loyola University Medical Center, Maywood, IL.
authors: Vishal
authors: V
authors: Gunnala
authors: Rong
authors: R
authors: Guo
authors: Carla
authors: C
authors: Minutti
authors: Ramon
authors: R
authors: Durazo-Arvizu
authors: Cynthia
authors: C
authors: Laporte
authors: Herbert
authors: H
authors: Mathews
authors: Stephanie
authors: S
authors: Kliethermis
authors: Rahul
authors: R
authors: Bhatia
mesh_terms: D000293:Adolescent; D000309:Adrenal Insufficiency / Q000097:blood / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D002853:Chromatography, Liquid / Q000379:methods; D015331:Cohort Studies; D016638:Critical Illness; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis* / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012463:Saliva / Q000737:chemistry / Q000378:metabolism*; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D006854:Hydrocortisone