A case of isolated hypothalamitis with a literature review and a comparison with autoimmune hypophysitis

• Published in: Endocrine Journal Vol. 68; no. 1; pp. 119 - 127
• Main Authors: Niri, Tetsuro, Horie, Ichiro, Kawahara, Hiromi, Ando, Takao, Fukuhara, Noriaki, Nishioka, Hiroshi, Inoshita, Naoko, Fujisawa, Haruki, Suzuki, Atsushi, Sugimura, Yoshihisa, Abiru, Norio, Kawakami, Atsushi
• Format: Journal Article
• Language: English
• Published: Japan The Japan Endocrine Society 01.01.2021; Japan Science and Technology Agency
• Subjects: Antibodies; Autonomic nervous system; Biopsy; Case reports; Cerebrospinal fluid; Diabetes insipidus; Diagnosis; Epidemiology; Glucocorticoids; Granulomatosis; Histiocytosis; Hyperphagia; Hypophysitis; Hypothalamitis; Hypothalamus; Infectious diseases; Inflammation; Langerhans cell histiocytosis; Lesions; Literature reviews; Magnetic resonance imaging; Methylprednisolone; Neoplasia; Pituitary (anterior); Pituitary (posterior); Prednisolone; Rabphilin-3A; Vasculitis; Rabphilin-3A; Hypothalamus; Diabetes insipidus; Hypophysitis; Hypothalamitis
• ISSN: 0918-8959; 1348-4540
• DOI: 10.1507/endocrj.EJ20-0300

Idiopathic hypothalamitis is a rare condition that can cause anterior pituitary dysfunction and central diabetes insipidus (CDI), occasionally accompanied by a disturbance of autonomic regulation known as hypothalamic syndrome. This condition has been described as a subtype of autoimmune (lymphocytic) hypophysitis; however, some cases of isolated hypothalamic involvement with no inflammatory lesions in either the pituitary gland or infundibulum have been reported. The detailed epidemiology and pathophysiology of isolated hypothalamitis have not been clarified. We herein report a case of a solitary hypothalamic lesion in a young woman who showed spontaneous development of CDI and panhypopituitarism accompanied by hyperphagia. The hypothalamic lesion increased from 11 × 7 to 17 × 7 mm over 16 months based on the sagittal slices of magnetic resonance imaging examinations. The negative results for anti-pituitary antibodies and anti-Rabphilin-3A antibodies suggested that upward extension of lymphocytic adenohypophysitis or infundibulo-neurohypophysitis was unlikely. Infectious disease, granulomatosis, Langerhans cell histiocytosis, vasculitis, and systemic neoplastic diseases were excluded by the findings of a laboratory investigation, cerebrospinal fluid examination, and imaging studies. To make a definitive diagnosis, we performed a ventriculoscopic biopsy of the hypothalamic lesion. Histology revealed an infiltration of nonspecific lymphoplasmacytes with no evidence of neoplasm, which was consistent with a diagnosis of idiopathic hypothalamitis. Subsequently, the patient was treated with methylprednisolone pulse therapy followed by oral prednisolone. The hypothalamic lesion improved and remained undetectable after withdrawal of the prednisolone, suggesting that the glucocorticoid treatment was effective for isolated hypothalamitis while the patient remains dependent on the replacement of multiple hormones.