Severe hypercalcemia following vitamin d supplementation in a patient with multiple sclerosis: a note of caution.
OBJECTIVE
To describe a patient with multiple sclerosis (MS) who developed severe hypercalcemia, attributed to the additive effect of 5500 IU of cholecalciferol and 2020 mg of calcium daily.


METHODS
Case report.


METHODS
University hospital.


METHODS
A 58-year-old woman with MS and osteoporosis presenting with acute-onset tremors and confusion.


METHODS
Serum calcium and 25-hydroxyvitamin D levels.


RESULTS
The patient's corrected serum calcium level was 15.2 mg/dL (reference range, 8.7-10.1 mg/dL; to convert to millimoles per liter, multiply by 0.25), and her 25-hydroxyvitamin D level was 103 ng/mL (to convert to nanomoles per liter, multiply by 2.496). The results of extensive laboratory tests to rule out hyperparathyroidism, malignant neoplasms, and other causes of hypercalcemia were unrevealing.


CONCLUSIONS
It is common practice to prescribe high-dose cholecalciferol to MS patients for its possible role in immunomodulation and relapse-rate reduction. Nevertheless, cholecalciferol may increase serum calcium, and there seems to be an additive effect when patients simultaneously use calcium supplements. This case underscores the need for physicians to be attentive to the possibility of hypercalcemia in patients treated with both high-dose cholecalciferol and calcium.
Department of Neurology, University of California, San Francisco, 350 Parnassus Ave, 908, PO Box 0114, San Francisco, CA 94143, USA. Jacqueline.marcus@ucsf.edu
Jacqueline F
JF
Marcus
Sarah M
SM
Shalev
Charles A
CA
Harris
Douglas S
DS
Goodin
S Andrew
SA
Josephson
D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000097:blood / Q000139:chemically induced*; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000178:diet therapy*; D014807:Vitamin D / Q000009:adverse effects* / Q000031:analogs & derivatives / Q000097:blood
D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium