Endocrine Abstracts

Introduction: Sarcoidosis may affect the central and peripheral nervous systems in 5–16% of patients. In most cases, such involvement occurs within a multi-systemic disease. Neurological involvement is rare but a potentially life-threatening form of sarcoidosis. The endocrine manifestations of neurosarcoidosis include hypothalamic dysfunction, diabetes insipidus, hypopituitarism, and amenorrhea–galactorrhea syndrome. Herein, we report the case of a patient with hypopituitarism secondary to neurosarcoidosis with no other manifestations of the disease.

Observation: A 35-year-old man was admitted for severe hyponatremia. His past medical history was unremarkable. The diagnosis of acute hypopituitarism with ACTH and TSH deficiencies was established. The patient was put on hydrocortisone and then levothyroxine. Initial pituitary magnetic resonance imaging (MRI) revealed a thickened pituitary stalk, an ectopic posterior lobe, and an intrasellar process. The second MRI performed 18 days later, showed pituitary necrosis and a partially empty sella with optic chiasm ptosis. Biological tests were normal (total calcium level, protein electrophoresis, serum angiotensin-converting enzyme (ACE) level). Tuberculin skin test showed tuberculin anergy. Direct staining and culture do not demonstrate the presence of mycobacteria in urine and sputum. Chest-x-ray and cervical-thoracic-abdominal-pelvic computed tomography scan were normal. Bronchoalveolar lavage and salivary gland biopsy were normal. Immunological investigations revealed the presence of atypical ANCA, normal IgG4 levels, and negative AAN. Cerebrospinal fluid examination showed an increased ACE level. The diagnosis of neurosarcoidosis was established and the patient was treated with high-dose oral corticosteroids.

Conclusion: Our case represents an unusual form of neurosarcoidosis. It should then be considered as part of the etiological diagnosis in patients with hypopituitarism especially when infiltrative lesions of the infundibulum, hypothalamus, or pituitary gland are identified.