Vitamin D deficiency
Vitamin D deficiency results from either lack of exposure to sunlight or impaired absorption. Malabsorption of vitamin D can occur in individuals with small bowel resections, celiac disease, inflammatory bowel disease, cystic fibrosis, or protein-losing enteropathies. Some medications (eg, phenytoin) can impair vitamin D absorption as well. Exclusively breastfed infants are also at high risk for vitamin D deficiency without adequate supplementation. Elderly, institutionalized, chronically ill, and darkly pigmented individuals are at high risk for vitamin D deficiency as well.
Patients with vitamin D deficiency are often asymptomatic, but children may present with bowing of the legs, a preference to sit, and rickets, while adults may present with chronic muscle aches and pains. In severe cases, adults may present with osteomalacia, a condition of defective bone mineralization.
E55.9 – Vitamin D deficiency, unspecified
34713006 – Vitamin D deficiency
- Impaired absorption – celiac disease, gastric bypass, inflammatory bowel disease (eg, Crohn disease, ulcerative colitis), cystic fibrosis, phenytoin use
- Inadequate intake / exposure – exclusively breastfed infants, northern altitude, darkly pigmented skin
- Obesity – increased adipose tissue decreases the bioavailability of fat-soluble vitamin D
- Osteopenia / osteoporosis – decreased bone mass with typically normal calcium and phosphate levels; of note, phenytoin can also cause osteopenia
- Primary hyperparathyroidism – presents with osteitis fibrosa cystica, usually associated with hypercalcemia
- Secondary hyperparathyroidism – usually due to chronic renal disease, associated with hypocalcemia and hyperphosphatemia
- Multiple myeloma – bone pain with hypercalcemia
- Child abuse – must distinguish history and radiologic findings of rickets from child abuse
- Elder abuse – must distinguish history and radiologic findings of new fractures from osteomalacia and osteoporosis, especially in the setting of preexisting osteoporosis
Last Updated: 01/31/2019