Vitamin D deficiency rickets caused by improper lifestyle in Japanese children.
BACKGROUND
Nutritional rickets is considered rare in developed countries. However, reports on vitamin D deficiency rickets caused by improper lifestyle have recently increased. The clinical and laboratory characteristics of patients with vitamin D deficiency rickets treated at Fukuoka Children's Hospital, Fukuoka, Japan, were evaluated to clarify current causes and ways to prevent this disease.


METHODS
Clinical records were reviewed, and obtained information and data were summarized.


RESULTS
Eight patients with vitamin D deficiency rickets (five boys and three girls) were treated during the past 10 years (January 1992 to December 2001). Two infants were referred to the hospital for hypocalcemia and convulsion, and six toddlers (1-2 years old) for bowlegs. One patient lacked exposure to sunlight, and six had an unbalanced diet. The cause of rickets could not be established in one patient. Anthropometric and laboratory data did not indicate malnutrition. Serum alkaline phosphatase was 2518.3 +/- 1401.7 IU/l, calcium was 8.2 +/- 2.6 mg/dL (including 4.7 mg/dL in one infant and 4.8 mg/dL in another), and phosphorus was 4.9 +/- 1.0 mg/dL. High sensitive parathyroid hormone was 1393.1 +/- 321.7 pg/mL (reference range, 180-560), 1,25-dihydroxyvitamin D was 86.0 +/- 61.5 pg/mL (reference range, 20-70), and 25-hydroxyvitamin D was 11.6 +/- 5.6 ng/mL (reference range, 10-30). The patients recovered with a change to a balanced diet, the promotion of weaning, and/or an increase in sunlight exposure.


CONCLUSIONS
Vitamin D deficiency rickets remains a common condition that is best managed by education and disease prevention.
Miyako
Kenichi
K
Department of Endocrinology and Metabolism, Fukuoka Children's Hospital, Fukuoka, Japan. ken-miyako@asahi.email.ne.jp
Kinjo
Saori
S
Kohno
Hitoshi
H
D000469:Alkaline Phosphatase / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism; D002675:Child, Preschool; D005260:Female; D006706:Homeostasis; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008019:Life Style; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D012279:Rickets / Q000453:epidemiology / Q000209:etiology*; D013472:Sunlight; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D010281:Parathyroid Hormone; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D000469:Alkaline Phosphatase