Understanding Hypercalcaemia: Causes and Implications

Hypercalcaemia, characterized by elevated calcium levels in the blood, can arise from various underlying conditions. A corrected serum calcium level of 2.66 mmol/L (10.64 mg/dL) signals a need for further investigation. Potential causes include excessive vitamin D intake from non-prescribed supplements, possible complications from prolonged tourniquet application during venesection, and the use of thiazide diuretics for hypertension. Moreover, a familial link to breast cancer associated with hypercalcaemia of malignancy may also be contributing factors that require careful consideration.

Familial hypercalcaemia presents a unique set of challenges. The most concerning form is Multiple Endocrine Neoplasia type 1 (MEN1), where primary hyperparathyroidism often emerges as an early sign. However, in cases where the affected individuals are asymptomatic and previous neck surgeries have not yielded results, familial benign hypercalcaemia might be the diagnosis. Recognizing this condition is crucial, as misdiagnosing it as primary hyperparathyroidism could lead to unnecessary parathyroidectomies.

In instances of pathological fractures, such as the one described, the underlying issue is often osteoporosis, particularly when the mechanism of injury appears trivial. Factors like post-menopausal age and prolonged use of glucocorticoids for conditions such as severe asthma can significantly contribute to bone density loss. Diagnosing osteoporosis typically involves a DEXA scan, and the management strategy often includes calcium and vitamin D supplementation, alongside bisphosphonate therapy, especially in patients on long-term glucocorticoids.

Additionally, the role of medications should not be overlooked. For instance, bendrofluazide may lead to mild increases in serum calcium levels. Elevated parathyroid hormone (PTH) levels might suggest vitamin D deficiency, particularly in individuals with inadequate sun exposure and a diet lacking in this essential nutrient. It's important to measure serum vitamin D levels and, if found to be low, initiate appropriate replacement therapy.

Ultimately, the interplay of these factors underscores the complexity of diagnosing and managing hypercalcaemia. Each patient's unique history and presentation play a significant role in determining the underlying cause and guiding treatment. Regular monitoring and a comprehensive approach are essential to ensure optimal outcomes for individuals affected by this condition.