Evaluation of vitamin D repletion regimens to correct vitamin D status in adults.

OBJECTIVE: To determine the efficacy and safety of commonly prescribed regimens for the treatment of vitamin D insufficiency. METHODS: We performed a retrospective analysis of 306 consecutive patients who were prescribed ergocalciferol (vitamin D2) for correction of vitamin D insufficiency at the Atlanta Veterans Affairs Medical Center between February 2003 and May 2006. Serum levels of parathyroid hormone, 25-hydroxyvitamin D (25-OHD), and calcium were compared before and after treatment with ergocalciferol. Patients who did not have a 25-OHD determination (n = 41) were excluded from analysis. Vitamin D deficiency, insufficiency, and sufficiency were defined as a serum 25-OHD level of <20 ng/mL, 21 to 29 ng/mL, and > or =30 ng/mL, respectively. RESULTS: We identified 36 discrete prescribing regimens. The 3 most common regimens were ergocalciferol 50,000 IU once weekly for 4 weeks followed by 50,000 IU once monthly for 5 months (n = 48); ergocalciferol 50,000 IU once monthly for 6 months (n = 80); and ergocalciferol 50,000 IU 3 times weekly for 6 weeks (n = 27). Each of these 3 treatments significantly increased serum 25-OHD (P<.01), but vitamin D sufficiency was achieved in only 38%, 42%, and 82% of study subjects, respectively. Regimens with >600,000 IU of ergocalciferol given for a mean of 60 +/- 40 days achieved sufficiency in 64% of cases, without vitamin D toxicity. CONCLUSION: In this study, regimens that contained at least 600,000 IU of ergocalciferol appeared to be the most effective in achieving vitamin D sufficiency. Guidelines for the treatment of vitamin D insufficiency in healthy adults should be developed.

Renal cell carcinoma presenting with paraneoplastic hypercalcemic coma: a case report and review of the literature.

We report a case of a 62-year-old woman with renal cell carcinoma (RCC) presenting with a hypercalcemia-induced coma. A laboratory evaluation indicated nonparathyroid-mediated hypercalcemia with an initial serum calcium level of 18.6 mg/dL. Our patient's parathyroid hormone (PTH)-related peptide level was undetectable. Initial imaging was negative, but PET scan identified a mass in the upper pole of the left kidney. Our patient underwent partial nephrectomy, and the mass was identified as RCC on final pathology. After surgery, her hypercalcemia resolved and PTH returned to normal limits. This case report describes a patient with RCC with the unusual presentation of hypercalcemic coma. We review the differential diagnosis of malignant hypercalcemia and the evaluation of hypercalcemia occurring with RCC. This case illustrates the need to carefully review and interpret all available data, especially when conventional testing in the work-up of hypercalcemia is unrevealing.