Lymphocytic hypophysitis

• Pembrolizumab-Induced Hypothyroidism and Diabetes Mellitus: A Rare Case Presentation Post-Treatment
• Development of Graves' disease in a patient with lymphocytic hypophysitis following glucocorticoid treatment
• Adrenal Insufficiency in Adults: A Review
• Intracranial Immunoglobulin G4-Related Disease Presented as Hypophysitis and Pachymeningitis: A Case Report
• Lymphocytic Hypophysitis Presenting as Acute-onset Arginine Vasopressin Deficiency and Pituitary Stalk Thickening: A Case Report
• A case of lymphocytic hypophysitis initially diagnosed as aseptic meningitis
• Primary autoimmune hypothalamitis: management strategies and long-term outcomes in a tertiary care setting with a focused review of literature
• Adrenal Insufficiency: Etiology and Characterization of Patients Attended at a University Center

Lymphocytic adenohypohysitis and lymphocytic infundibulo neurohypophysitis are rare autoimmune mediated diseases of the anterior and posterior pituitary, respectively. Lymphocytic hypophysitis is a relatively rare autoimmune disease defined by lymphocytic infiltration to the pituitary.

It is closely related to other inflammatory conditions in the region, namely orbital pseudotumor and Tolosa Hunt syndrome.

Lymphocytic hypophysitis is seen most frequently in women (strong female predilection with a M:F of ~ 9:1), and often in the post-partum period or in the third trimester of pregnancy.

Clinical presentation is varied depends of part of the pituitary affected and on the size of the lesion. Lymphocytic hypophysitis can thus be classified as:

anterior pituitary: Lymphocytic adenohypohysitis (LAH)

most common

mimics a pituitary neuroendocrine tumor

endocrine hormone deficits are common

mass effects on adjacent structures (e.g. optic chiasm)

posterior pituitary: lymphocytic Infundibular neurohypophysitis (LINH)

rare

diabetes insipidus

both anterior and posterior pituitary: lymphocytic Infudibular panhypophysitis (LIPH)

Occasionally lymphocytic hypophysitis may be associated with auto-immune conditions such as:

autoimmune thyroiditis

pernicious anaemia

It is characterised by infiltration of the pituitary stalk with lymphocytes (as the name would suggest).

Radiographic features

CT

Coronal CT and multiplanar reconstructions are able to visualise the pituitary region reasonably well. Lymphocytic hypophysitis appears as an enhancing soft tissue mass involving the pituitary and extending into the suprasellar region.

MRI

MRI, as is the case with other pituitary lesions, is the best modality for assessing this condition which appears as a pituitary region mass.

T1 affected region is isointense with slight signal heterogeneity normal posterior pituitary bright spot may be absent T1 C+ (Gd) can variably enhance, usually homogeneously dural enhancement may be present infundibulum may be thickened

T2 Hypointensity in parasellar region can be present and may be useful in differentiating from a pituitary neuroendocrine tumor

Lymphocytic hypophysitis is usually self limiting and spontaneous recovery can occur. Corticosteroids are sometimes given and deficient hormones can be replaced 8

The differential diagnosis is essentially that of other pituitary region masses. Considerations include:

pituitary neuroendocrine tumor

craniopharyngioma (papillary type)

suprasellar meningioma

pituitary metastasis

Granulomatous hypophysitis (idiopathic of secondary to systemic illness e.g sarcoidosis, syphilis, and tuberculosis).

Pekic S, Bogosavljevic V, Peker S, Doknic M, Miljic D, Stojanovic M, Skender-Gazibara M, Gacic EM, Popovic V, Petakov M. Lymphocytic Hypophysitis Successfully Treated with Stereotactic Radiosurgery: Case Report and Review of the Literature. J Neurol Surg A Cent Eur Neurosurg. 2017 Jul 25. doi: 10.1055/s-0037-1604079. [Epub ahead of print] PubMed PMID: 28743133 ¹⁾.