Unusual Presentation of Central Diabetes Insipidus in a Patient With Neurosarcoidosis

Hypothalamic-Pituitary Axis Dysfunction, Central Diabetes Insipidus, and Syndrome of Inappropriate Antidiuretic Hormone Secretion as the First Clinical Presentation of Neurosarcoidosis: Why Early Diagnosis and Treatment is Important?

Sarcoidosis is defined by granuloma formation in a multitude of organs. Despite its rare involvement in the nervous system, there are a number of cases that identify neurological symptoms to be the initial clinical manifestation of sarcoidosis. The involvement of the hypothalamic-pituitary (HP) axis presented most frequently with hormone deficiencies. Studies have reported that damage to the pituitary gland may be irreversible, and hormone abnormalities were generally permanent. Neurosarcoidosis has been described as the underlying cause of central diabetes insipidus (DI) and syndrome of inappropriate antidiuretic hormone (SIADH) secretion. The pathological mechanism that can lead both to deficiency and excess of antidiuretic hormone (ADH) secretion is still not fully understood. It has been shown that diagnosis of neurosarcoidosis remains challenging, as symptoms can be inconclusive and diagnostic tools are not sufficiently sensitive and specific. Early treatment may potentially reverse pituitary deficiencies, although studies to confirm this hypothesis are minimal. This review article aims to increase knowledge about central DI and SIADH caused by neurosarcoidosis, identify possible difficulties in diagnosis, and discuss the importance of early management. Clinical trials investigating the long-term therapeutic response in patients with HP sarcoidosis are essential, as there are currently no established guidelines for the treatment of neurosarcoidosis.

Neurosarcoidosis Presentation as Adipsic Diabetes Insipidus Secondary to a Pituitary Stalk Lesion and Association with Anti-NMDA Receptor Antibodies

Sarcoidosis is a multisystemic inflammatory disease of unknown cause. It is characterized by the presence of noncaseating granuloma on a biopsy specimen. Clinical presentation varies across case report series with myriad of symptoms ranging from fever, respiratory symptoms, and skin lesions, or atypical symptoms like heart block or neurological symptoms. Hence, we report the case of a 22-year-old woman with encephalitis, a pituitary mass, and adipsic diabetes insipidus. The diagnostic approach did not end on the biopsy of the lesion, which reported noncaseating granulomas; on the contrary, it was the beginning of a path to exclude other causes of the central nervous system granulomas that ended with the diagnosis of the isolated central nervous system sarcoidosis. Also, we report the first proven association between anti-NMDA receptor antibodies and sarcoidosis.