Endocrine Abstracts

Introduction: Hypoparathyroidism (HPTH) is an uncommon condition resulting in the production of insufficient amounts of parathyroid hormone (PTH) by the parathyroid glands consequently affecting the calcium phosphate balance. The most frequent etiology of HPTH is the damage to or removal of the parathyroid glands due to a surgery for another condition. Other causes, including autoimmunity and genetic disorders may be responsible for HPTH. Our aim is to compare the different clinical, biological and evolutive aspects of postsurgical HPTH to non-surgical HPTH.

Patients and methods: It is a retrospective study that collected data from 61 patients diagnosed with hypoparathyroidism that were hospitalized in the Department of Endocrinology, Hedi Chaker University Hospital, Sfax over 12 years.

Results: The most common etiology of HPTH was postsurgical HPTH found in 45 cases (74%), including 40 women and 5 men. The mean age of the patients that underwent surgery was 41.5 years. A clear female predominance with a sex ratio (F/M) of 8. The type of intervention was total thyroidectomy in 29 cases, subtotal thyroidectomy in 11 cases and parathyroidectomy in 7 cases. The diagnosis of HPTH was made within the first few days post-intervention. The mean serum calcium level within the first week of surgery was 1.8 mmol/l (extremes: 1.24-2.38 mmol/l). The hypocalcaemia was symptomatic in 29 cases. In 31 cases, the patients required urgent treatment with intravenous calcium salts as well as oral calcium supplementation. Transient HPTH was observed in 3 patients with a mean recovery time of 2.5 months whereas as permanent HPTH was found in 34 patients. Only the presence of clinical signs of hypocalcaemia within the first week post-intervention was significantly correlated as a predictive risk factor for permanent HPTH. More trophic and psychic disorders were found in non-postsurgical HPTH whereas there was no significant difference in serum calcium levels. A more favorable clinical outcome under calcium supplementation therapy in postsurgical HPTH than in non-postsurgical HPTH.

Conclusion: HPTH is a rare affection which results from an absence or reduced secretion of PTH form parathyroid glands resulting in the inability to maintain extracellular calcium homeostasis. One of the most common causes either of transient or permanent HPTH remains post-thyroid surgery. Serum calcium dosage within the first days of thyroid or parathyroid surgery is primordial as well as monitoring the patients for clinical symptoms so as to detect hypocalcaemia and treat it effectively and accordingly.