Characteristics of vitamin D deficiency in early infancy

Purpose: Vitamin D deficiency is a health problem in developing countries. This study aims to investigate the characteristics of children with vitamin D deficiency in early infancy. 
Materials and Methods: Hundred and forty infants with vitamin D deficiency (mean age:3.5 ± 1.7 [0-6] months) and a control group of 200 healthy infants (mean age: 3.4 ± 1.7 [0-6] months) were included in the study. Serum calcium, phosphorus, alkaline phosphatase, parathyroid hormone (PTH), and 25-hydroxyvitamin D (25(OH)D) levels were measured in the patient, control groups, and the mothers of the patients. In 38 patients, radiological findings were evaluated with knee and wrist radiographs. Thacher Rickets Severity Scoring (RSS) system was used for radiological evaluation of rickets severity. 
Results: The most common (42%) complaints were respiratory symptoms, including cough, respiratory distress, and wheezing. The most common finding of physical examination was the rachitic rosary. Serum calcium (Ca++), alkaline phosphatase (ALP), 25(OH) vitamin D, and parathormone (PTH) levels were significantly different in the patient and the control groups. The mean Thacher radiological score of 38 patients was 3.1 ± 2.1 (0-8) points. The mother's dressing style of covering up the whole body, i.e., veiling, increased the infant's risk of vitamin D deficiency by 17.5 times. 
Conclusion: Subtle clinical, laboratory, and radiological findings of vitamin D deficiency are detected in early infancy. Vitamin D deficiency should be considered primarily in infants with hypocalcemia whose mothers are less frequently exposed to sunlight due to geographical conditions and their preferred or imposed lifestyle.