Endocrine Abstracts

Introduction: Sarcoidosis is a rare systemic disease where clusters of immune cells form granulomas in various organs of the body. Its prevalence ranges from 1-40 per 100,000 people in Europe. Neurological involvement of the disease occurs in 5-10% of cases, with the hypothalamus-pituitary gland being one of the most commonly affected structures.

Clinical Case: A 36-year-old male with a history of hypertension, obesity, asthma and OSAS. He went to the emergency department due to symptoms of 4 months of evolution of asthenia, hypersomnia, compulsive food intake with a weight gain of 30 kg and behavioral disorders, being admitted to the Internal Medicine department. Physical examination revealed a weight of 157 kg, height 177 cm (BMI 50.1) and white striae on the abdomen. Cardiopulmonary auscultation was normal. Neurologically, there was evidence of decreased strength and painful stiffness on extension in the upper limbs.

Cranial CT scan showed two intracranial lesions, at hypothalamic and right parietal level, with associated perilesional oedema. These lesions were confirmed by MRI, suggesting an inflammatory-granulomatous aetiology. Fine-needle aspiration with Endo Bronchial Ultra Sound of a mediastinal lymph node revealed non-necrotising granulomatous lymphadenitis and a diagnosis of systemic neurosarcoidosis was made. Treatment with corticosteroids, rituximab and mycophenolate mofetil was started. After discharge, he was admitted to the intensive care unit a few days later due to disturbance of consciousness consciousness secondary to hypernatraemia. Ionogram showed a serum sodium of 172 mEq/l with a plasma osmolality of 380 mOs/Kg and a urinary osmolality of 843 mOsm/kg. The endocrinology department, after ruling out diabetes insipidus and assessing the hormone analysis, diagnosed it of hypothalamic syndrome secondary to neurosarcoidosis, presenting with hypernatraemia due to hypodipsia/adipsia, morbid obesity, type 2 diabetes mellitus, hypogonadotropic hypogonadism and hyperprolactinaemia. At discharge, treatment for diabetes was started with metformin and weekly dulaglutide, hormone replacement therapy was started with testosterone gel and a controlled water intake of 2.5-3 litres per day was indicated, depending on physical activity and the season of the year.

Conclusions: - Hypothalamic syndrome as a consequence of neurosarcoidosis can affect a number of vital endocrine and non-endocrine functions that are difficult to control.

- Hypothalamic adipsic hypernatremia can present with severe symptoms and these patients should be educated in controlled fluid intake.