The role of intra-operative parathyroid hormone assay in non-localized adenoma

The incidence of primary hyperparathyroidism (PHPT) is increasing in trend due to more common practice of routine blood investigations especially in the elderly. Surgery is the only curative therapy in symptomatic patients. We present a case of a 63-year-old lady with generalised body weakness associated with occasional muscle cramps. Her biochemical results were consistent with PHPT. As a result of persistent severe hypercalcemia, surgery was planned. However, the pre-operative anatomical and functional radiological imaging (neck ultrasonography, ^99mTc-MIBI and FDG-PET scans) failed to identify the abnormal parathyroid gland. Therefore, bilateral neck exploration with intra-operative parathyroid hormone (io-PTH) measurement was performed. The nodular left thyroid and adenomatous right superior parathyroid glands were removed. Possible causes of negative localization and incorporation of io-PTH in under-resourced countries to ensure successful surgery are discussed.