Hypophysitis

Abstract

Hypophysitis is defined as the presence of any inflammatory process of the pituitary gland, that may involve the anterior lobe, the posterior lobe and/or the infundibulum, and is classified in three main histopathological types: lymphocytic, granulomatous, and xanthomatous. The epidemiology of hypophysitis, which encompasses a broad variety of primary and secondary inflammatory diseases, is changing due to the emergence of new causative factors, including treatment with immune checkpoint inhibitors. Hypophysitis may also be of infective origin, part of an IgG4-related disease, or occur secondarily to other sellar lesions and/or tumors. Sarcoidosis and other systemic granulomatous and histiocytic disorders may occasionally involve pituitary gland. As different conditions can be suspected according to the clinical context, the indications for diagnostic neurosurgery are decreasing. However, histopathological examination remains a cornerstone in many cases. The clinical implications of hypopituitarism, in particular adrenal insufficiency, should be promptly treated in order to prevent morbidity and mortality. Mass effects, with their potential neurosurgical implications, and diabetes insipidus are additional concerns. This article provides a synthetic update on the physiopathology, clinical presentation, diagnosis, and treatment of the different forms of hypophysitis. The need for interdisciplinary collaboration and multidisciplinary management of affected patients is emphasized.