Category: Calcium/Bone Disorders
Vitamin D deficiency is a common problem worldwide. It has been associated with increased risk of fractures and osteomalacia. It has been commonly found in post gastrectomy patients due to limited food intake and malabsorption caused by reduced acidity or malfunction of small bowel. Osteomalacia appears to be the major bone lesion due to vitamin D deficiency in post gastrectomy patients.
Methods : A 48 year old female with a past medical history of breast cancer, RA, Sjorgren’s disease and gastrectomy with multiple abdominal surgeries was referred to endocrine clinic for evaluation of vitamin D deficiency. Patient had underwent gastrectomy after two Nissen procedures for symptoms of reflux and regurgitation of food particles. Her vitamin D level was noted to be 6 ng/ml which increased to 23 ng/ml in one year with oral supplementation. Goal for her Vitamin D was kept at 50ng/ml due to worsening bone mineral density on bone scan caused by osteomalacia despite supplementation. She was initially on liquid vitamin D supplementation but later she developed diarrhea on a daily basis on this medication. An option to try intramuscular injection of vitamin D was discussed with the patient.
Labs were drawn every two weeks after vitamin D intramuscular injection. She received 150,000 IU once. She experienced side effects of mild headache and malaise after the injection which subsided with rest and hydration. Her Vitamin D level increased to 28 next visit with reduction in PTH (after 1 month). A oral form of vitamin D3 of 2000u/day was added to her regimen as an adjunct to her therapy. After two injections at 4 months on therapy her vitamin D normalized to 32ng/ml.
Vitamin D2 and D3 are rarely available in intramuscular (IM) injection preparations. Currently IM formulation of vitamin D is difficult to obtain in the US due to variability in the potency of different vitamin D preparations. Many studies have indicated that IM administration of vitamin D3 may provide a more sustained increase in 25(OH)D concentrations in the body compared to oral supplementation. Although currently not FDA approved, it can be an effective alternate route of administration in patients with malabsorption, intolerance and noncompliance to oral vitamin D medications.
Effective use of IM vitamin D in patients with history of gastrectomy or malabsorption is not commonly used in the US population. Our case study shows effective use of IM vitamin D in a patient with history of gastrectomy and multiple abdominal surgeries as an alternate agent where patients have failed oral supplementation or remain intolerant to them.
University of Florida Department of Medicine
Endocrinology Fellow at University of Florida Jacksonville