Endocrine Abstracts

Hypoparathyroidism (HP) is a rare disease characterized by an absence or inappropriately low concentrations of circulating parathyroid hormone, leading to hypocalcaemia, hypophosphatemia and elevated urinary calcium excretion.

Aim: To determine complications in chronic post-surgical HP patients.

Material and methods: We have analyzed the data from 76 patients (71 women and 5 men; median age 51.8 years (range 18–77)) with chronic post-surgical HP reviewed during 2017–2019. We present the main characteristics of patients including a volume of surgery, disease duration, biochemical parameters, treatment modalities and disease-associated complications.

Results: The average HP duration in group was 8.7 years (2–32). In most cases HP developed after total thyroidectomy for nontoxic unilateral/multinodular goiter and well-differentiated thyroid carcinoma (38.2% and 30.3% respectively). Other reasons included diffuse toxic goiter (14.5%), thyroid malignancy with central neck dissection (10.5%) and primary hyperparathyroidism due solitary adenoma (6.6%). 15 patients (19.7%) were diagnosed with HP after the reoperation on neck region. The median levels of serum Ca and albumin-adjusted serum Ca on conditional therapy were 2.03 mmol/l (1.83; 2.24) and 1.97 mmol/l (1.78; 2.15) respectively. Patients required alfacalcidol in medium doses of 1.5 mcg/day (min 0.25; max 6.0) and calcium carbonate in medium doses of 1875 mg/day (min 250; max 4500). 12 patients received thiazide diuretics in doses 25–75 mg/day to control the hypercalciuria. We did not reveal hypomagnesaemia (0.76 mmol/l (0.71; 0.8)) and vitamin D deficiency (32.75 ng/ml (28.1; 42.9)) in study group. The following complications were identified: decrease of estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73 m² in 9 patients (11%); nephrocalcinosis and kidney stones in 4 (5%) and 17 (22%) patients respectively. A diagnosis of hypoparathyroid-caused cataract was confirmed in 5 (6.5%). 5 patients suffered from central nervous system calcifications (Fahr’s syndrome) detected by CT scan results. An electrocardiogram showed HP-associated cardiac arrhythmias and prolongation of the corrected QT interval in 5 patients (6.5%). Symptoms of myopathy with increased serum levels of creatine phosphokinase and ossification of longitudinal spine ligament were identified in 8 (10%) and 4 (5%) respectively.

Conclusion: Chronic HP and its treatment may lead to long-term complications affecting various organ systems and consequently the quality of life thus active screening of these patients is strongly recommended. The longitudinal studies and further research are required to develop the new effective strategies in prevention of long-term HP complications.