Small changes in calcium replacement therapy triggering hypercalcaemia and rising creatinine - a case series

Area of Science:

• Nephrology
• Endocrinology
• Clinical Pharmacology

Background:

• Hypoparathyroidism management post-thyroid surgery often involves calcium and vitamin D supplementation.
• Medication formulation changes can inadvertently alter drug absorption and physiological effects.
• Hypercalcemia is a known complication of calcium and vitamin D therapy.

Observation:

• Four cases of acute kidney injury (AKI) secondary to hypercalcemia were identified.
• The AKI occurred following minor adjustments to calcium supplement regimens.
• Excipient changes in calcium preparations were implicated in two cases.

Findings:

• Minor changes in calcium supplement preparations led to significant hypercalcemia and subsequent renal failure.
• Cessation of the implicated calcium preparation and intravenous rehydration reversed the renal impairment.
• Patient education on consistent supplement intake and prescriber awareness of formulation changes are critical.

Implications:

• Healthcare providers must recognize that seemingly minor medication changes, including excipient variations, can have serious clinical consequences.
• Emphasizing consistent calcium and vitamin D supplement use to patients is crucial for preventing adverse events.
• Further investigation into the impact of excipients on calcium supplement bioavailability is warranted.