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Hypercalcaemia After a Sunny Holiday
Shannon Ferrie1, Puneet Malhotra2, Alan Amal Calist1
1General Medicine, Whiston Hospital, Merseyside, GBR.
None:
Severe hypercalcaemia can be life-threatening, and presentation is often non-specific. We report a case of a man who returned from a sunny holiday in Portugal with abdominal symptoms, confusion, and severe hypercalcaemia with normal serum parathyroid hormone (PTH). Routine blood tests, including serum calcium, performed in primary care two months before his holiday, were normal. Imaging during admission revealed bilateral hilar lymphadenopathy. Endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA) from mediastinal lymph nodes showed multiple non-caseating granulomas, consistent with a diagnosis of sarcoidosis. Hypercalcaemia was attributed to excess calcitriol (1,25-dihydroxyvitamin D) production by activated macrophages within sarcoid granulomas, exacerbated by recent sunlight exposure. The patient responded to intravenous fluids and corticosteroids, with subsequent steroid-sparing treatment using methotrexate. This case highlights the importance of considering sarcoidosis in PTH-independent hypercalcaemia.
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