Severe hypercalcemia requiring acute hemodialysis: A retrospective cohort study with increased incidence during the Covid-19 pandemic

BACKGROUND: The Covid-19 pandemic has had dramatic consequences on the progression of numerous pathologies, especially neoplastic ones. The orientation of hospital activities toward the care of patients with SARS-Cov2 infection has caused significant delays in the diagnosis and therapy of many other pathologies. What about severe hypercalcemia? The aim of this work was to determine the clinical and biological presentation, etiologies, mortality, and the impact of the Covid-19 pandemic on severe hypercalcemia. MATERIAL AND METHODS: we conducted a retrospective study for 84 months (September 2014 to September 2021) at the Nephrology Unit in University Hospital Mohammed VI, Oujda, Morocco. Included were all adult patients diagnosed with severe hypercalcemia (defined as corrected total serum calcium of >3.5 mmol/l or > 14.0 mg/dl) and who had benefited from one or more hemodialysis sessions. RESULTS: 66 episodes of severe hypercalcemia occurred in 64 patients. The mean age was 57 ± 15 years and 57.6% were female. The mean corrected serum calcium at admission was 16.9 ± 2.1 mg/dl and 33.3% had more than 18.0 mg/dl. Malignancies represented 80.4% of all etiologies. Acute kidney injury was observed in 69.7%. The delta drop in serum calcium 48 h after initiation of medical treatment was 4.64 ± 1.63 mg /dl. Mortality was noted in 14% of all cases. Electrocardiographic abnormalities were observed in 58.3%, 87.5% and 85.7%, respectively, in group 1 (14.0–16.0 mg/dl), group 2 (16.1–18.0 mg/dl), and group 3 (> 18.0 mg/dl) (p = 0.04). The mean serum potassium value was 5.1 ± 1.3, 4.0 ± 1.0, and 3.7 ± 0.7 respectively, in group 1 (14.0–16.0 mg/dl), group 2 (16.1–18.0 mg/dl), and group 3 (> 18.0 mg/dl) (p < 0.001). Newly diagnosed neoplasia, severe hypercalcemia (> 16.0 mg/dl), and mortality have been observed in 15.4% vs. 23.7% (p = 0.31), 25% vs. 50% (p = 0.03), and 35.7% vs. 52.6% (p = 0.13) respectively, in patients before and during the Covid-19 pandemic. CONCLUSIONS: The Covid-19 pandemic caused an increase in both the incidence and severity of hypercalcemia and the hemodialysis practiced in this context remains efficient and safe.