Endocrine Abstracts

A 61-year-old female, with a previous history of left nephrectomy for papillary renal cell carcinoma, presented with lethargy. Her initial blood tests revealed an adjusted calcium of 4.26 mmol/l (normal range 2.2–2.6) associated with acute renal impairment (creatinine 432 μmol/l, urea 25 mmol/l) and low PTH of 9 ng/l (normal range 20–75). Following rehydration with IV fluids and IV pamidronate administration, her adjusted calcium normalised to 2.37 mmol/l. The initial impression was that her hypercalcaemia was most likely malignancy related. Imaging including CXR, renal US, CT scan of thorax, abdomen, pelvis and MRI brain and whole spine were all unremarkable. A bone isotope scan revealed abnormal increased uptake over both hemithoraces suggestive of soft tissue calcification. On further questioning, it appeared that the patient had been taking a full packet (36 tablets) of Setlers antacid (calcium carbonate 500 mg per tablet) per day for the previous 6 weeks for indigestion indicating her hypercalcaemia was due to Milk Alkali Syndrome. The medication was stopped. Three months later, a repeat bone isotope scan, showed that the increased uptake over the right hemithorax had resolved with reduced intensity over the left hemithorax. Several months later her calcium levels remained normal. About 90% of cases of hypercalcaemia are caused by primary hyperparathyroidism or malignancy, however, this case illustrates the importance of considering less common causes of hypercalcaemia even in a patient with a history of cancer.