Vitamin D in incident nephrotic syndrome: a Midwest Pediatric Nephrology Consortium study.
BACKGROUND
Cross-sectional studies of children with prevalent nephrotic syndrome (NS) have shown 25-vitamin D (25(OH)D) deficiency rates of 20-100 %. Information on 25(OH)D status in incident patients or following remission is limited. This study aimed to assess 25(OH)D status of incident idiopathic NS children at presentation and longitudinally with short-term observation.


METHODS
Multicenter longitudinal study of children (2-18 years old) from 14 centers across the Midwest Pediatric Nephrology Consortium with incident idiopathic NS. 25(OH)D levels were assessed at diagnosis and 3 months later.


RESULTS
Sixty-one children, median age 5 (3, 11) years, completed baseline visit and 51 completed second visit labs. All 61 (100 %) had 25(OH)D < 20 ng/ml at diagnosis. Twenty-seven (53 %) had 25(OH)D < 20 ng/ml at follow-up. Fourteen (28 %) children were steroid resistant. Univariate analysis showed that children prescribed vitamin D supplements were less likely to have 25(OH)D deficiency at follow-up (OR 0.2, 95 % CI 0.04, 0.6). Steroid response, age, and season did not predict 25(OH)D deficiency. Multivariable linear regression modeling showed higher 25(OH)D levels at follow-up by 13.2 ng/ml (SE 4.6, p < 0.01) in children supplemented with vitamin D.


CONCLUSIONS
In this incident idiopathic NS cohort, all children at diagnosis had 25(OH)D deficiency and the majority continued to have a deficiency at 2-4 months. Supplemental vitamin D decreased the odds of 25(OH)D deficiency at follow-up, supporting a role for supplementation in incident NS.
Division of Nephrology, Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI, USA. dselewsk@med.umich.edu.
David T
DT
Selewski
Department of Pediatrics, Section of Pediatric Nephrology, Wake Forest Baptist Health, Winston-Salem, NC, USA.
Ashton
A
Chen
Division of Pediatric Nephrology and Hypertension, Sidra Medical and Research Center, Doha, Qatar.|Medical University of South Carolina, Charleston, SC, USA.
Ibrahim F
IF
Shatat
Department of Pediatric Nephrology, St. John's Medical College Hospital, St John's National Academy of Health Sciences, Bangalore, India.
Priya
P
Pais
Emory University and Children's Healthcare of Atlanta, Atlanta, GA, USA.
Larry A
LA
Greenbaum
Division of Nephrology, Department of Pediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada.
Pavel
P
Geier
Division of Nephrology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA.
Raoul D
RD
Nelson
Department of Pediatrics, University of Kentucky, Lexington, KY, USA.
Stefan G
SG
Kiessling
Stead Family Department of Pediatrics, Division of Nephrology, University of Iowa, Iowa City, IA, USA.
Patrick D
PD
Brophy
DeVos Children's Hospital, Grand Rapids, MI, USA.
Alejandro
A
Quiroga
Division of Pediatric Nephrology, Department of Pediatrics, Washington University at St. Louis, St. Louis, MO, USA.|Department of Pediatrics, Southern Illinois University, Springfield, IL, USA.
Michael E
ME
Seifert
Department of Pediatrics, Louisiana State University and Children's Hospital, New Orleans, LA, USA.
Caroline E
CE
Straatmann
Nationwide Children's Hospital, The Ohio State University, College of Medicine, Columbus, OH, USA.
John D
JD
Mahan
Pediatric Nephrology, UNC Kidney Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Maria E
ME
Ferris
Division of Nephrology, Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI, USA.
Jonathan P
JP
Troost
Division of Nephrology, Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, University of Michigan, Ann Arbor, MI, USA.
Debbie S
DS
Gipson
D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D015994:Incidence; D016014:Linear Models; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D015146:Midwestern United States / Q000453:epidemiology; D015999:Multivariate Analysis; D009404:Nephrotic Syndrome / Q000175:diagnosis / Q000453:epidemiology*; D016017:Odds Ratio; D010281:Parathyroid Hormone / Q000097:blood; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D014808:Vitamin D Deficiency / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*
D015415:Biomarkers; C470125:PTH protein, human; D010281:Parathyroid Hormone; D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; C104450:25-hydroxyvitamin D
25(OH)D deficiency; Children; Nephrotic syndrome; Pediatric; Vitamin D