[Not Available].

Primary hyperparathyroidism (PHPT) is the most prevalent cause of hypercalcaemia, affecting 0.3% of the population. The only curative procedure is parathyroidectomy. Ectopic adenomas are challenging to localize and frequently result in persistent PHPT. This is a case report of a 29-year-old male patient who was diagnosed with PHPT prior to neck surgery and reoperated with bilateral neck exploration. However, the PHPT was not cured, until diagnostic CT with contrast had helped localizing a 1 cm ectopic parathyroid adenoma in the right horn of the thymus gland. The adenoma was then removed successfully.