Endocrine Abstracts

A 68 years old lady was referred to our endocrine clinic after she had routine blood tests done as a part of monitoring of her chronic kidney disease stage 3. She had high corrected calcium of 2.85 mmol/l and parathyroid hormone levels of 13 pmol/l consistent with primary hyperparathyroidism. She was clinically symptomatic with high calcium and had polyuria, polydipsia and constipation. There was no history of renal calculi or fractures although DEXA scan confirmed osteoporosis. She had a neck ultrasound scan which could not localize any parathyroid adenoma. Sestamibi scan showed reduced wash out close to the midline inferior to the thyroid isthmus raising the possibility of parathyroid adenoma. Given the discrepancy in both results, she underwent CT neck with contrast which showed a 6 mm enhanced nodule in correlation with the sestamibi result again raising the possibility of an adenoma. She underwent neck exploration and had excision of nodule identified on the neck CT. Histology was consistent with benign parathyroid tissue and not suggestive of an adenoma or hyperplasia. She remained hypercalcaemic and later had SPECT MIBI which localized ectopic parathyroid adenoma within thymus. She underwent further surgery which resulted in cure of primary hyperparathyroidism with post operative PTH of less than 0.3 pmol/l and corrected calcium of 1.91 mmol/l. Histology confirmed a benign parathyroid adenoma. She is now maintained on alfacalcidol and corrected calcium is just at the lower end of the normal reference range at 2.15 mmol/l. This case highlights the importance of pre operative localization of pathological parathyroid gland and the use of SPECT MIBI in such challenging cases given its much higher sensitivity compared with planar sestamibi scan.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.