title: Incidence of vitamin D deficiency rickets among Australian children: an Australian Paediatric Surveillance Unit study.
abstract: OBJECTIVE
  To determine the incidence of and factors associated with vitamin D deficiency rickets in Australian children.
  
  
  METHODS
  18-month questionnaire-based prospective observational study, using Australian Paediatric Surveillance Unit (APSU) data.
  
  
  METHODS
  Australian paediatricians and child health workers, January 2006 - July 2007.
  
  
  METHODS
  Children aged ≤ 15 years with vitamin D deficiency rickets (25-hydroxyvitamin D [25OHD] ≤ 50 nmol/L, and elevated alkaline phosphatase levels [> 229 IU/L] and/or radiological rickets).
  
  
  METHODS
  Incidence of vitamin D deficiency rickets. Description of demographics, clinical presentation, identification and further analysis of overrepresented groups, and treatment regimens compared with best-practice guidelines.
  
  
  RESULTS
  We identified 398 children with vitamin D deficiency (55% male; median age, 6.3 years [range, 0.2-15 years]). The overall incidence in children ≤ 15 years of age in Australia was 4.9/100 000/year. All had a low 25OHD level (median, 28 nmol/L [range, 5-50 nmol]) and an elevated alkaline phosphatase level (median, 407 IU/L [range, 229-5443 IU/L]), and 48 (12%) were hypocalcaemic. Ninety-five children had wrist x-rays, of whom 67 (71%) had rachitic changes. Most (98%) had dark or intermediate skin colour and 18% of girls were partially or completely veiled. Most children were born in Africa (252; 63%) and 75% of children were refugees. Duration of exclusive breastfeeding was inversely related to serum vitamin D levels in children < 3 years of age. Empirical vitamin D treatment was given to 4% of children before diagnosis.
  
  
  CONCLUSIONS
  Vitamin D deficiency rickets is a significant problem in Australia among known high-risk groups. Public health campaigns to prevent, identify and tre@vitamin D deficiency, especially in high-risk groups, are essential.
authors.affiliation: Institute of Endocrinology and Diabetes, Children's Hospital at Westmead, Sydney, NSW. craigm2@chw.edu.au
authors.forename: Craig F
authors.initials: CF
authors.lastname: Munns
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Simm
authors.forename: Christine P
authors.initials: CP
authors.lastname: Rodda
authors.forename: Sarah P
authors.initials: SP
authors.lastname: Garnett
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Zacharin
authors.forename: Leanne M
authors.initials: LM
authors.lastname: Ward
authors.forename: Janet
authors.initials: J
authors.lastname: Geddes
authors.forename: Sarah
authors.initials: S
authors.lastname: Cherian
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Zurynski
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Cowell
mesh_terms: D000293:Adolescent; D000349:Africa / Q000208:ethnology; D000469:Alkaline Phosphatase / Q000097:blood; D001315:Australia / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D012036:Refugees; D012279:Rickets / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000175:diagnosis / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000469:Alkaline Phosphatase