Endocrine Abstracts

Objective: To assess the levels of osmolality, sodium in blood and urine, and copeptin level in patients after transnasal adenomectomy for pituitary adenomas.

Materials and methods: A total of 154 patients, aged 18 to 65 years, were included in this study and underwent transnasal adenomectomy. Surgical treatment was performed in 73 patients with Cushing’s disease, 66 – acromegaly, 4 – prolactinoma, 9 – hormonally inactive adenoma, 1 – Nelson syndrome, 1 – TSH-oma. Before and after surgery, patients were assessed the sodium levels, blood and urine osmolality, and 30 patients were tested for copeptin.

Results: The development of a permanent form of central diabetes insipidus (central DI) in the postoperative period was noted in 22 patients (14.3%), transient form was detected in 39 patients (25.3%). In 2 patients (1.3%) development of hyponatremia was noted. In 91 patients (59%) there was no development of water-electrolyte disturbances. When assessing the level of blood osmolality in the dynamics of patients of different groups, no statistically significant differences were found (P>0.05), however, when assessing the blood sodium level, significant differences were revealed in the postoperative period in patients with transient DI compared to the group of patients without water-electrolyte disorders (P=0.024 and P=0.015 for 1–3 and 5–7 days of follow-up, respectively), and significant differences in pre- and postoperative sodium levels were found in patients with transient (P<0.008) and permanent form of DI (P<0.05). When assessing the level of copeptin, there were no statistically significant differences between pre- and postoperative levels, but patients with a permanent central DI form had a sharp decrease in its level (median 10.13 (6.181; 10.98) pmol/L before the procedure, 5.265 [4.7, 8.262] pmol/L after the intervention). When assessing the level of osmolality and sodium in urine, significant differences in the indices of osmolality and sodium in patients with a constant and transient form of central DI were found in comparison with patients without disturbances (P<0.05), and significant differences in the level of osmolality of urine in the dynamics in patients with transient form of the central DI (P<0.006).

Conclusions: Blood sodium, osmolality and sodium in urine indicators are sensitive markers for diagnosis and prediction of further development of water-electrolyte disturbances in the early postoperative period. The level of copeptin as a predictor of the development of the permanent form of central DI, is a promising marker for further study.