Nutritional rickets in young Nigerian children in the Sahel savanna.

OBJECTIVES

To determine the prevalence of clinical and biochemical rickets in an under-five out-patient population, relate the prevalence of biochemical rickets (BR) to the sociocultural characteristics of families and determine the response of nutritional rickets to vitamin D therapy.

DESIGN

Prospective cross-sectional and retrospective case-series surveys.

SETTING

Paediatric general out-patient and consultant clinics.

SUBJECTS: One hundred and ninety eight out-patients and twenty two patients aged >1 to 60 months treated for nutritional rickets.

INTERVENTIONS: Clinical examination, interview with mothers and determination of biochemical abnormalities of under-fives and management of patients with rickets using stosstherapy.

MAIN OUTCOME MEASURES: Prevalence of BR and response to stosstherapy.

RESULTS

Eight (4%) patients in the survey had clinical and biochemical rickets while 33 (17%) had biochemical rickets only; 92 (47%) other patients had isolated hypocalcaemia and/or hypophosphataemia. The prevalence of BR was higher in males (p <0.05), and increased with age (p <0.001). The prevalence was lower in families who were indigenous to the area (p <0.05), children of Moslem families (p <0.05) and children whose mothers were full-time housewives, unskilled or traders (p <0.01), and who lacked any formal western education (p = 0.157). Three of the seven evaluable patients who received stosstherapy responded late.

CONCLUSION

The results support the hypothesis that deficiency or reduced availability of dietary calcium may be of at least equal importance with vitamin D deficiency in the aetiology of nutritional rickets in the Sahel savanna.