Spurious hypocalcemia after gadodiamide-enhanced magnetic resonance imaging: a case report and review of the literature.

Gadolinium-enhanced magnetic resonance imaging is a diagnostic modality widely used in urologic practice. We report on a 54-year-old woman in whom a critically low serum calcium level was measured with standard colorimetric assay after gadodiamide-enhanced magnetic resonance imaging. The same phenomenon was noted in 2 other patients seen in our practice. Repeat serum calcium measurements performed several hours later were within normal limits. Commercially available gadolinium-based contrast agents might precipitate critically low serum calcium values when measured by standard colorimetric assay. Physician awareness of gadodiamide-induced spurious hypocalcemia might prevent unnecessary therapeutic interventions.