Endocrine Abstracts

Introduction: Sheehan syndrome (SS), or postpartum pituitary necrosis, is a complete or dissociated adeno-pituitary insufficiency due to hypovolemia secondary to excessive blood loss during or after delivery. Although few studies have investigated osteoporosis in isolated hormone deficiencies, the relationship between SS and osteoporosis has not been investigated in large series of SS. In this study, we aimed to evaluate bone mineral density (BMD) in patients with SS.

Patients and methods: This is a descriptive cross-sectional study, involving 65 patients. It was carried out in the Endocrinology-Diabetology department of University Hospital Farhat Hached in Sousse, Tunisia, over a period of nine months, from July 2019 to March 2020. Patients were evaluated by Dual Energy X-ray absorptiometry to determine bone mineral density (BMD), T-score and Z-score.

Results: The mean age at diagnosis of SS was 48.2 ± 12.4 years. The incidence of SS in our study was 2.8 cases/year. A causal hemorrhagic delivery was found in all of our patients. Thyrotropic and corticotropic insufficiency were present in 86.2% of our patients, followed by gonadotropic and lactotroph insufficiency in 72.3% and 38.5% of patients, respectively. Somatotropic insufficiency was explored by a dynamic test in only 8 patients, concluding with somatotropic deficiency in 10.8% of cases. Hormone replacement therapy was initiated in all patients based on the affected anterior pituitary axis. In no case has the somatotropic sector been substituted in our series. Bone densitometry was performed in 21 patients, on average 5 years after the diagnosis of SS. Bone mineralization disorders were found in 18 patients: 10 patients had osteoporosis and 8 patients had osteopenia. The lumbar spine was more frequently involved than the femoral neck. Two patients had femoral neck fractures associated with low energy falls, on average 33 years after the diagnosis of SS. In univariate analysis, bone mineral loss was correlated with age, body mass index, vitamin D level, duration of SS and estrogen progesterone Hormone replacement. However, in multivariate analysis no factor was significantly correlated with an elevated risk of bone mineral loss.

Discussion-Conclusion: Anterior pituitary insufficiency, especially in sex and growth hormones, as well as an overdose of thyroid hormones and glucocorticoids could increase bone mineral loss. In fact, bone loss is increased in SS compared to other causes of anterior pituitary insufficiency since patients with SS had an earlier disease onset and more severe hormonal deficits.