Endocrine Abstracts

Isolated sarcoidosis of the hypothalamic-pituitary system is a very rare form of neurosarcoidosis. It usually leads to secondary damage to endocrine function, resulting in hypopituitarism and diabetes insipidus. A 32-year-old male patient with progressive deterioration of his general condition, weakness, polyuria, dizziness and visual field disturbances was admitted to the Department of Endocrinology for the diagnosis of a tumor in the hypothalamic-pituitary region. MRI showed a tumor (19x16x15 mm) with suprasellar extension, and hormonal evaluation revealed multi-hormonal pituitary insufficiency and diabetes insipidus. The patient was referred for pituitary surgery: the lesion initially described in MR as a tumor was sub totally removed from the fronto-parietal access. The histopathological examination revealed a hypothalamic sarcoidosis. Based on the imaging studies performed, the presence of sarcoid lesions in other typical locations (lungs, lymph nodes, heart, eye, skin) was excluded. Isolated sarcoidosis of the pituitary system was diagnosed. Methylprednisolone treatment was initiated at 500 mg/week for 6 weeks, followed by 250 mg/week for 6 weeks. Additionally, the patient required replacement treatment with l-thyroxine, testosterone and desmopressin. Following 12 weeks of methylprednisolone therapy MRI showed a progression of the infiltrative process: the tumor was enlarged (20x19x17 mm) and two satellite foci appeared. Due to the clinically and radiologically identified steroid resistance of the lesions, immunosuppressive treatment with methotrexate was introduced in the 15 mg sc regimen for 7 days for 4 weeks, and then 25 mg sc every 7 days chronically. Subsequent MRI examinations performed 3, 12 and 24 months after the initiation of methotrexate therapy showed a regression of the infiltrative process in the CNS and decompression of the optic chiasm together with clinical improvement and no signs of sarcoid lesions in other locations. At the same time, no complications of the applied treatment were observed. In the control hormonal tests, the features of multi-hormonal anterior pituitary insufficiency were maintained, which required continuation of substitution treatment. In conclusion, an optimal treatment of isolated neurosarcoidosis of the hypothalamic-pituitary system has not been clearly established. Steroid therapy with high doses of methylprednisolone should be considered first, but the possibility of steroid resistance should also be considered. The use of immunosuppressants, such as methotrexate as a second line therapy, may have a positive effect on reducing the extent of the sarcoid process. Such a treatment is effective and safe, although the time frame and the dosing schedule of methotrexate are still unknown.