Endocrine Abstracts

Hypocalcaemia is a common presentation to the emergency department; patient’s symptoms vary but typically report pins and needles and muscle cramps, due to neuromuscular irritability. Other important features include ECG changes (prolonged QTc) and seizures. The most common causes are hypoparathyroidism, vitamin D deficiency and chronic kidney disease.

A 25-year old male presented with symptomatic hypocalcaemia who was referred to us for follow up, after replacement.

On examination he was short of stature, a stocky build, obese for his height and clinically had shorter 4^th metacarpals. He had 2 siblings on his father’s side with similar body habitus. He had coexisting hypothyroidism, but was not on replacement as it was stopped aged 12.

Additionally he described a syncopal episode 6 months prior to presentation, with no features of epilepsy.

His serum calcium was 1.47 mmol/L with elevated PTH at 54 pmol/L and a phosphate of 1.78 mmol/L. He was also severely vitamin D deficient with a level of 19 nmol/l. His TSH was 10.3 mU/L suggesting subclinical hypothyroidism. A diagnosis of pseudo-hyperparathyroidism was suspected and X-rays of his hands, along with a CT head were arranged to assess his 4–5th metacarpal joints and to look for evidence of basal ganglia calcification. These investigations supported the diagnosis of Albright hereditary osteodystrophy. He was managed with calcitriol, a more active form of vitamin D, but unfortunately developed an urticarial rash. Therefore he was given alfacalcidol and sandocal; with the goal of therapy to maintain calcium levels, supress PTH to normal levels and avoid hypercalciuria. This case highlights the investigations and management of hypocalcaemia and the importance of considering more unusual causes, such as pseudo-hyperparathyroidism.