Life-Threatening Calcium Chloride Ingestion

Abstract

Calcium chloride dihydrate (CaCl₂·2H₂O), a common component in household dehumidifiers in South Korea, poses a significant risk of toxicity upon ingestion. We present a case of life-threatening hypercalcemia following intentional calcium chloride dihydrate ingestion, with a focus on electrolyte homeostasis and physiological adaptation. An 86-year-old Korean woman presented with transient unconsciousness after ingesting dehumidifier fluid. She exhibited drowsiness and developed sinus tachycardia 10 h later. Severe hypercalcemia (19.4 mg/dL) was the main biochemical disturbance. Parathyroid hormone was initially suppressed but later rose, facilitating renal calcium excretion and phosphorus regulation. Electrolyte levels normalized by day 4. Prompt treatment, including gastric lavage and cardiac management, led to a full recovery. A rapid parathyroid hormone response played a crucial role in restoring calcium balance.

Keywords: Calcium chloride dihydrate; Dehumidifiers; Deliberate ingestion; Hypercalcemia; Parathyroid hormone.

Figure 1

Sequential measurement of (upper; Y-axis is a logarithmic scale) serum levels of intact parathyroid hormone (pg/mL) and 24-h urine calcium and phosphorus (mg in 24-h urine), and (lower) serum calcium and phosphorus (mg/dL). Notably, the initial parathyroid hormone level, indicated by the downward arrow, was much lower than the levels measured after recovery. This result suggests that parathyroid hormone levels decreased immediately after CaCl₂ ingestion, accompanied by increased renal calcium and decreased renal phosphorus excretion. In parallel, serum calcium and phosphorus levels gradually normalized by the fourth day of hospitalization. The normal reference ranges were as follows: 24-h urine phosphorus < 250 mg (females), 24-h urine calcium 400 - 1,300 mg, and serum intact parathyroid hormone 15 - 65 pg/mL. Reference values for serum calcium and phosphorus are shown in Table 1. Creatinine clearance, measured by 24 h urine on day 2, 3, and 6, was 41.7, 37.5, and 46.7 mL/min, respectively.