Nutritional rickets and osteomalacia in school children and adolescents

OBJECTIVE: To review experiences of nutritional rickets and osteomalacia in school children and adolescents at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia.

METHODS: Records of children and adolescents aged 6-18 years, seen at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, during the period January 1994 through to December 1999, who were diagnosed to have rickets or osteomalacia were reviewed. The diagnosis was based on clinical, biochemical and radiological data. Data extracted and analyzed included age, sex, presenting symptoms and signs, dietary history and sun exposure, blood count, bone profiles, renal and liver profile, and 25-hydroxy vitamin D3 and 1, 25 dihydroxy vitamin D3. Hand and wrist x-rays were carried out for all patients while bone density of lumbar spine and 3 femoral sites and bone scan were performed on the majority of patients.

RESULTS: Forty-two children and adolescents (25 females and 17 males) were diagnosed. Their age ranged between 6-18 years with a mean of 13.5. Non specific symptoms, such as bone pain and fatigue were the most presenting symptoms, while skeletal deformities and fractures were the presenting symptoms in only 5 and 3 patients. Lack of direct sun exposure and poor calcium intake was evident. Bone profiles at the time of diagnosis revealed mean serum calcium of 2.1 mmol/L, range 1.5-2.3 (Normal=2.2-2.7), phosphorus 1.1 mmol/L, range 0.7-1.9 (Normal=1.4-2.1) and alkaline phosphatase activities of 1,480 U/L, range 834-2,590 (N=<600). Serum concentrations of 25-hydroxy Vitamin D were low (<10 mg/L) while that of 1, 25 Dihydroxy Vitamin D varied between low to normal (<10-45 ng/L). Bone density of the lumbar spine and 3 femoral sites were performed in 26 patients and showed markedly reduced values, while bone scan demonstrated a high uptake of tracer throughout the skeleton "super scan". Multiple stress fractures were evident in 8 children.

CONCLUSION: Although a community-based study to assess the magnitude of the problem is needed, it seems that rickets and osteomalacia of nutritional origin are not that uncommon and deserves special attention from all pediatricians and practicing physicians. They also suggested that further studies are needed to help understand the pathophysiology, and identify the contributing factors for the development of the disorder.