Endocrine Abstracts

19-year-old gentleman was initially investigated by his local hospital when he presented with 2-year history of diarrhoea, intermittent abdominal pain, sweating, and depression with suicidal ideation. His only past medical history was eczema. His maternal grandmother had PTHP aged 50 years. A paternal grandmother had colon and pancreatic cancer and cousin had Graves’ disease.

Gastroenterology investigations were normal. However he was found to have hypercalcaemia with elevated, PTH and high 24 h urine calcium:creatinine ratio which was consistent with PHPT. USS was suggestive of right lower parathyroid adenoma but sestamibi scan was inconclusive. He had a right inferior prathyroidectomy but histology showed normal parathyroid and he remained hypercalcaemic post-operatively.

He was then referred to Hammersmith hospital for further investigation. His symptoms continued post-operatively. Repeat investigations confirmed PTHP with a 24 h calcium:creatinine ratio of 0.017, calcium: 2.82, PO₄: 1.17 and an elevated PTH. He had no nephrocalcinosis in USS but osteopenia in DEXA scan.

In addition, in view of his young age it is our routine practice to exclude MEN 1. A biochemical screen and genetic test for MEN 1 was performed and it was negative for a mutation. His pituitary function and gut hormones profile were normal.

He had further localisation studies were unhelpful with negative repeat sestamibi scan USS and CT scan of the neck. Therefore he underwent PTH sampling which showed a 10 × 5 mm diameter oval vascular blush on the left side of the neck with concordant rise in PTH levels at this site. Although CT scan had been reported as normal, in retrospect this did revealed 10 × 5 mm diameter oval soft tissue abnormality lying between left side of the trachea and the left lobe of the thyroid. He is now awaiting surgical removal of the parathyroid adenoma.

This case highlights that PTH adenomas may be found in unusual places particularly if the localization studies are negative. We would also recommend MEN 1 genetic screen in any patient who develops PHPT below the age 40 years.