Endocrine Abstracts

Primary hyperparathyroidism in the most common cause of hypercalcemia. 87% of the cases present with single adenoma, 9% of them have hyperplasia, while multiple adenomas and parathyroid malignancy are detected in 3 and 1% of the cases, respectively. Although it is rare, parathyroid adenomas may be ectopic. The most common locations for ectopic parathyroid adenomas are thymus, tracheaesophageal cleft, carotis sheet, intrathyroidal and paraesophageal area. In this study, we aimed to present an intrathymic parathyroid adenoma as a rare case.

A 46-year old female patient who received hemodialysis for chronic renal failure secondary to chronic glomerulonephritis for 7 years and then underwent cadaveric renal transplantation in 2010 was presented for routine follow-up visit. Laboratory examination revealed urea:19 mg/dl(n:15–43),creatinin:0.8 mg/dl(n:0.57–1.11)), calcium:11.5 mg/dl (n:8.6–10.2 mg/dl), phosphorus:2.7 mg/dl (n:2.4–5.1 mg/dl), albumin:4.2 g/l (n:3.2–4.8 g/l), iPTH:340 pg/ml (n:15–68), creatinin clerarance in 24-h urine: 82 ml/min, calcium in 24-h urine: 410 mg/day. Neck ultrasonography was performed, which demonstrated 12×9 mm sized well-circumscribed nodular lesion with heterogeneous echo at inferior part of lower pole of left thyroid gland (thyroid nodule? Parathyroid adenoma?). Femoral neck and L1–L4 vertebra were osteopenic on bone densitometry. Parathyroid scintigraphic examination detected no scintigraphic signs characteristic for parathyroid adenoma in the neck and mediastinum. The patient underwent parathyroidectomy following surgical exploration. Histopathologic examination of parathyroidectomy material revealed intrathymic parathyroid adenoma. The patient was scheduled for outpatientclinic follow-up with post-operative laboratory findings of iPTH: 38 pg/ml, Ca:9.9 mg/dl, P:2.5 mg/dl, Alb:4.3 g/l, kreatinin:0.7 mg/dl.

Annual incidence of primary hyperparathyroidism is 0.27%. Since Primerhiperparatiroidizmin yıllık görülme oranı % 0.27dir. Since both thymus and parathyroid gland embrologically derive from 3rd pharyngeal cleft, ectopic parathyroid adenomas may locate within thymus. It is very important to pre-operatively determine the localisation of ectopic parathyroid adenomas to prevent surgical errors.