Nutritional Rickets in Ekiti, Southwestern Nigeria: Investigating the Roles of Calcium and Vitamin D

Abstract

          Background: Nutritional rickets remains a common cause of skeletal deformities among children in developing countries. While vitamin D deficiency is traditionally implicated, evidence from tropical regions with abundant sunlight suggests calcium deficiency may be more prominent.

Objectives: This study evaluated the relative roles of calcium and vitamin D in children with rickets in Ekiti, Southwestern Nigeria.

Methods: A descriptive comparative study was conducted involving 32 children with clinical features of rickets and 32 age- and sex-matched controls without rickets at Ekiti State University Teaching Hospital, Ado-Ekiti. Sociodemographic and clinical data were collected, and biochemical analyses included serum calcium, phosphate, alkaline phosphatase (ALP), vitamin D, total protein, albumin, and renal function tests. Radiographs of wrists and knees were obtained for affected children. Independent sample t-tests compared mean biochemical values, while Chi-square tests assessed associations between variables. Statistical significance was set at p < 0.05.

Results: The mean age of affected children was 3.06 ± 0.13 years (range 2–5 years). Bilateral genu varum was the most common presentation (31.3%). Hypocalcaemia was observed in 87.5% of cases and elevated ALP in 75.0%, whereas 87.5% had normal serum vitamin D levels. Significant differences between cases and controls were found for serum calcium (p = 0.02) and ALP (p = 0.01), but not for vitamin D or protein levels. Renal parameters were largely normal.

Conclusion: Calcium deficiency appears to be the predominant biochemical abnormality in children with rickets in this tropical setting, despite adequate sunlight exposure and largely normal vitamin D levels. Emphasis on calcium assessment and supplementation is essential for effective management and prevention.

Keywords:

Nutritional rickets, calcium deficiency, vitamin D, alkaline phosphatase, tropical region, Nigeria.

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