Misleading acute hypercalcemia due to hyperlipidemia: a method-dependent error.
OBJECTIVE: To report a case of artifactual hypercalcemia in a patient with hyperlipidemia. METHODS: We present clinical data and laboratory findings in a 33-year-old woman with generalized fatigue, a recent 5-kg weight loss, and a papular rash on the extremities as well as a history of diabetes and hypertension. RESULTS: Physical examination revealed an obese patient with eruptive xanthomas and lipemia retinalis. Laboratory tests showed hyperlipidemia, hypercalcemia (serum calcium measured by spectrophotometry), anemia, hyperproteinemia, hyperuricemia, and hyperbilirubinemia. After 4 days of a low-fat, low-cholesterol diet and gemfibrozil therapy, the serum triglyceride level decreased, and the serum calcium concentration returned to normal. CONCLUSION: In patients with hypercalcemia without an obvious cause, a spurious measurement should be considered.