Post-operative Transient Hypoparathyroidism: Incidence and Risk Factors

Abstract

Background: There is limited data on the incidence and risk factors for developing postoperative hypoparathyroidism (POHP) in the South African setting. Objectives: This study aims to calculate the incidence of postoperative hypoparathyroidism in a South African tertiary setting, and to compare local risk factors for POHP to international published data. Methods: All patients who underwent a total or completion thyroidectomy at an academic referral center from January 2010 to December 2015 were included. Data reviewed included post-operative parathyroid hormone (iPTH) level, demographics, type of operation and lymphadenectomy, size of thyroid glands resected, final histology, extra capsular extension of carcinomas, number of lymph nodes resected, and the number of parathyroid excised. Results: Postoperatively, 29% of patients were diagnosed with hypoparathyroidism. Overall, there was no association between POHP and age or gender. In patients with
benign histology, size was significantly associated with higher rates of POHP. In patients with thyroid carcinoma, lymphadenectomy and the number of lymph nodes resected were associated with higher rates of POHP. Conclusion: The incidence of immediate postoperative hypoparathyroidism is within international standards. Standardized postoperative follow up is necessary, and strategies to improve POPH such as auto transplantation in locally identified high-risk subgroups should be considered.

Key words: Postthyroidectomy, Hypocalcaemia, Hypoparathyroidism