Characterization of a cohort of patients with hypercalcemia in a tertiary pediatric hospital

Introduction. Hypercalcemia is infrequent in pediatrics, of diverse etiology, and with multiorgan morbidity. Objective. Describe the etiology, biochemistry, clinical, and treatment in pediatric patients with hypercalcemia. Population and methods. Retrospective and descriptive study of a cohort of patients with hypercalcemia between 2008 and 2022. They were classified into three groups (G): hypercalcemia of iatrogenic cause (G1), parathyroid hormone (PTH) independent (G2), or PTH-dependent (G3). Results. One hundred forty-seven patients were included; 57% were male, with a median age of 3.7 years, median calcemia of 11.8 mg/dl, and mean phosphatemia of 4.9 mg/dl. Symptoms were present in 29% of patients, and 28.6% required additional treatments to those of the first line. In G1, 76 patients (51.7%) were included; in G2, 58 (39.4%), and in G3, 13 (8.8%). Median calcemia was lower in G1 vs. G2 and G3 (11.6 mg/dl, 12.6 mg/dl, and 12.3 mg/dl), and mean phosphatemia was lower in G3 vs. G1 and G2 (3.7 mg/dl, 5.3 mg/dl, and 4.9 mg/dl). Most of the patients with hypercalcemia were asymptomatic and did not require additional treatments. The percentage of symptomatic patients and the percentage requiring additional treatment were lower in G1 than in the other two groups. Conclusions. Iatrogenesis was the most frequent cause, presenting lower calcemia, while PTH-dependent causes presented the lowest phosphatemia. PTH-independent causes represented a diagnostic and therapeutic challenge due to lacking a characteristic biochemical profile.