Endocrine Abstracts

Mr RP is a 69 year old gentleman who presented to A&E following a fall. He described several weeks of lethargy, ataxia, confusion and polydipsia. He had a past medical history of hypertension and COPD, but was otherwise fit and well. On admission bloods revealed an adjusted calcium of 5.25, with a PTH of 2.4. He also had a significant AKI with an eGFR of 22. After initial management with IV fluids, a cautious dose of pamidronate was given. Basic investigations did not identify a cause for the hypercalcaemia. Bendroflumethiazide was stopped, but it was not felt that this was the sole cause. Over the next 10 days, his symptoms resolved and he was discharged with an adjusted calcium of 2.83 and eGFR 35. Over the forthcoming months he had extensive investigations into the cause of the hypercalcaemia. Malignancy was thought to be most likely given the low PTH, despite no constitutional symptoms. Bloods revealed PSA 1.7 and ALP 109, and no evidence of Multiple Myeloma. CT-chest/abdomen/pelvis and bone scan were normal. Recurrent PTH levels were low but detectable. In light of a PTH of 2.4, despite a calcium above 5, it was felt prudent to investigate further for primary hyper-parathyroidism. Both US and Sestmibi scan of the parathyroids did not reveal an adenoma. The only abnormality of note on his bloods was a raised ACE at 84. Following discussion with the respiratory team and the radiologists, it was felt that a diagnosis of Sarcoid was a possibility, however there was little evidence to support this diagnosis and no lesion to biopsy. PTHrP result is pending. Regular monitoring of the calcium was performed, which varied dramatically on a week-to-week basis. On two occasions over the last couple of months, the calcium was found to be greater than 3, but without intervention dropped to the normal range within 1 week.

This case posed a number of difficulties for us as physicians.

i) What further investigations could help make a diagnosis?

ii) Are there any cyclical causes of hypercalcaemia?

iii) How frequently do we need to monitor this gentleman’s calcium level?

iv) At what calcium shall we treat this gentleman given the drastic variation in results?

v) How do we manage expectations in our patients when a diagnosis is not found?