title: Prevalence of renal abnormality in pediatric intestinal failure.
abstract: BACKGROUND
  Outcomes of children with intestinal failure have improved over the last decade. However, with improved survival, other co-morbidities have become evident. The goal of our study was to evaluate the presence of renal nephrocalcinosis or increased echogenicity in a cohort of patients with pediatric intestinal failure (PIF).
  
  
  METHODS
  A cross-sectional prevalence design was performed in PIF patients followed by our intestinal rehabilitation program between 2013 and 2014. Renal function was evaluated using serum creatinine and urea, urine oxalate, creatinine, calcium, and calcium/creatinine ratios. Renal ultrasounds were performed to assess for echogenicity. Data was collected on intestinal failure related factors and nutritional intake. Data was analyzed using medians and Mann-Whitney U or proportions and chi square.
  
  
  RESULTS
  Fifty-four patients (median age 48months; 33 males (61%) were studied. Twenty-two patients (41%) had increased echogenicity or nephrocalcinosis on ultrasound. There were no differences in serum Creatinine or urea, but patients with nephrocalcinosis had statistically different calcium:creatinine ratio (1.69 vs 0.74; p=0.043), urine oxalate (108 vs 219; p=0.06), and serum phosphate (1.55 vs 1.75; p=0.044). Patients with echogenicity had a shorter colonic remnant (25cm vs 31cm; p=0.01), a history of longer PN exposure (928 vs 483days; p=0.05), percent PN calories (37 vs 0; p=0.05), PN h/day (13 vs 0; p=0.05), but no difference in PN Ca/phosphate/magnesium content (mmol/kg).
  
  
  CONCLUSIONS
  A large proportion of PIF patients have increased echogenicity/nephrocalcinosis on ultrasound that is associated with prolonged PN exposure. This has implications for long-term management. Regular surveillance is required, and further study is warranted to determine specific risk factors.
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Christina
authors.initials: C
authors.lastname: Kosar
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Nicole
authors.initials: N
authors.lastname: De Silva
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada; Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Yaron
authors.initials: Y
authors.lastname: Avitzur
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Karen
authors.initials: K
authors.lastname: Steinberg
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Glenda
authors.initials: G
authors.lastname: Courtney-Martin
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Chambers
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Kevin
authors.initials: K
authors.lastname: Fitzgerald
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada; Division of Nephrology, The Hospital for Sick Children, University of Toronto, Canada.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Harvey
authors.affiliation: Group for Improvement of Intestinal Function and Treatment (GIFT), The Hospital for Sick Children, University of Toronto, Canada; Division of General and Thoracic Surgery, The Hospital for Sick Children, University of Toronto, Canada. Electronic address: paul.wales@sickkids.ca.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Wales
mesh_terms: D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007422:Intestines / Q000002:abnormalities*; D007668:Kidney / Q000002:abnormalities* / Q000000981:diagnostic imaging; D007677:Kidney Function Tests; D008297:Male; D009397:Nephrocalcinosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D014463:Ultrasonography
keywords: Intestinal failure; Parenteral nutrition; Pediatric; Renal abnormality