title: The Association between Serum 25-Hydroxy Vitamin D Level and Urine Cathelicidin in Children with a Urinary Tract Infection.
abstract: OBJECTIVE
  Cathelicidin is an important antimicrobial peptide in the urinary tract. Cathelicidin expression is strongly stimulated by 1,25-dihydroxy vitamin D in epithelial cells, macrophages/monocytes, and neutrophils. Vitamin D and cathelicidin status in children with urinary tract infection (UTI) caused by Escherichia coli is unknown. To establish the relationship between serum vitamin D and urine cathelicidin levels in children with a UTI caused by Escherichia coli.
  
  
  METHODS
  Serum 25-hydroxy vitamin D and urine cathelicidin levels were measured in 36 patients with UTI (mean age 6.8±3.6 years, range: 0.25-12.6 years) and 38 controls (mean age 6.3±2.8 years, range: 0.42-13 years).
  
  
  RESULTS
  There were no significant differences in urine cathelicidin levels between the study and control groups (p>0.05). Eight (22.2%) patients in the study group and 21 (58.3%) children in the control group were found to have sufficient vitamin D (≥20 ng/mL). Patients with sufficient vitamin D had higher urine cathelicidin levels than the controls with sufficient vitamin D (respectively 262.5±41.1 vs. 168±31.6 ng/mL, p=0.001). There were no significant differences between the patients and controls with insufficient vitamin D (p>0.05).
  
  
  CONCLUSIONS
  The children with vitamin D insufficiency may not be able to increase their urine cathelicidin level during UTI caused by Escherichia coli. There is a need of prospective studies in order to prove a beneficial effect of vitamin D supplementation for the restoration of cathelicidin stimulation and consequently for prevention of UTI recurrence.
authors.affiliation: Gülhane Military Medical Academy, Haydarpaşa Training and Research Hospital, Clinic of Pediatrics, İstanbul, Turkey, Phone: +90 533 727 08 50 E-mail: duyguovunc@yahoo.com.tr.
authors.forename: Duygu
authors.initials: D
authors.lastname: Övünç Hacıhamdioğlu
authors.forename: Demet
authors.initials: D
authors.lastname: Altun
authors.forename: Bülent
authors.initials: B
authors.lastname: Hacıhamdioğlu
authors.forename: Ferhat
authors.initials: F
authors.lastname: Çekmez
authors.forename: Gökhan
authors.initials: G
authors.lastname: Aydemir
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kul
authors.forename: Tuba
authors.initials: T
authors.lastname: Müftüoğlu
authors.forename: Selami
authors.initials: S
authors.lastname: Süleymanoğlu
authors.forename: Ferhan
authors.initials: F
authors.lastname: Karademir
mesh_terms: D000293:Adolescent; D023181:Antimicrobial Cationic Peptides / Q000652:urine*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D004927:Escherichia coli Infections / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D014552:Urinary Tract Infections / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D054804:Cathelicidins
chemical_list: D023181:Antimicrobial Cationic Peptides; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D054804:Cathelicidins