Hypervitaminosis D Rarely Causes Hypercalcemia: The New Concept ''Subclinical Intoxication"

Objective: In clinical practice, hypercalcemia may not be observed with very high serum 25 OH vitamin D levels. The reason for this is unknown. Our aim in this study is to reveal the percentage of hypercalcemia in patients with very high serum 25 OH vitamin D levels.Methods: Between January 1, 2016 and October 31, 2017, 22996 patients who were referred to hospital and examined 25 OH vitamin D levels from all patients were screened at the Dicle University Medical Faculty Hospital. Patients with 25 OH vitamin D levels> 150 mu g/L were included in the study. The calcium, phosphorus, creatinine, albumin and parathormone values of these patients, if any, were checked. Rates of hypercalcemia in patients with hypervitaminosis D were evaluated. The vitamin D preparations they used were recorded. Serum 25 OH Vitamin D was measured by HPLC method.Results: A total of 27 patients with serum 25 OH vitamin D> 150 mu g/L were detected. The ratio was approximately 1/1000 (0.0013). The mean age was 56 +/- 20 (24-90) years. Twenty-one of the 27 patients in our study were female (78%) and 6 were male (12%). Serum 25 OH Vitamin D level averaged 184.81 +/- 35.37 (150.51-279.64) mu g/L, serum 25 OH vitamin D levels after replacement were measured after a mean of 2.10 +/- 1.58 months. The mean serum calcium level was 9.48 +/- 0.52 (8.4-10.9) mg/dL, and the serum calcium level of one patient was above normal (10.9 mg/dL). The percentage of hypercalcemia in patients with serum 25 OH vitamin D level> 150 mu g/L was 3.70%.Conclusion: As a result, very high levels of vitamin D do not show hypercalcemia. When vitamin D level is above the level of toxicity, calcium and phosphorus control should be performed. Very high vitamin D levels are often attributed to too much ampoule use. Close follow-up and appropriate dose treatment of the patients will solve this problem.