Efficacy and safety of parenteral vitamin D therapy in infants and children with vitamin D deficiency caused by intestinal malabsorption

Purpose: Oral supplementation of vitamin D can be inefficient in patients with vitamin D deficiency caused by intestinal malabsorption. This study investigated the efficacy and safety of parenteral vitamin D supplementation in infants and children with vitamin D deficiency caused by intestinal malabsorption. Methods: This study included 11 patients with vitamin D deficiency who were unresponsive to oral vitamin D or were unable to try oral vitamin D therapy due to underlying conditions. All patients were treated with weekly intramuscular injection of cholecalciferol 50,000 IU. Radiological findings and biochemical parameters including serum calcium, phosphorus, alkaline phosphatase, 25-hydroxyvitamin D-3 (25(OH)D-3), and parathyroid hormone levels were reviewed retrospectively. Results: Underlying diseases included small bowel atresia (n=3), necrotizing enterocolitis (n=3), congenital megacolon (n=2), chronic intestinal pseudo-obstruction (n=1), congenital mesenteric band (n=1), and Crohn disease (n=1). Three patients exhibited rickets on X-ray findings. The mean duration of treatment was 4.8 +/- 2.9 weeks. The alkaline phosphatase levels were decreased from 710 +/- 650 IU/L to 442 +/- 284 IU/L (P=0.143). The 25(OH)D-3 level was increased from 6.0 +/- 3.4 ng/mL to 50.4 +/- 28.8 ng/mL (P=0.008) after 3 months. Two patients with rickets showed improved radiologic findings after parenteral treatment. Conclusion: Parenteral vitamin D therapy was effective and safe in patients with vitamin D deficiency caused by intestinal malabsorption. Long-term follow-up is needed to establish the efficacy of parenteral vitamin D therapy in a large number of patients.