Abstract 20
Category: Clinical Science
At the end of the session, participants will be able to:
- Describe the histopathology of lymphocytic hypophysitis.
- Describe the inflammation associated with other pituitary lesions (PitNET, cyst, apoplexy)
- Summarize the (possible) pathogenesis and clinical significance of lymphocytic hypophysitis.
COI Disclosure:
None to disclose.
Presenter
Dr. Del Bigio is a Professor – Department of Pathology, University of Manitoba (since 1994).
MD 1982; PhD 1987; FRCPC (Neuropathology) 1993
Marc R. Del Bigio
Department of Pathology, University of Manitoba and Shared Health Manitoba, Winnipeg Canada
Target Audience:
Pathologists, Residents, Medical Students
CanMEDS:
Medical Expert (the integrating role), Health Advocate
Pituitary inflammatory lesions including lymphocytic hypophysitis: a 30-year single centre experience
Abstract
In Manitoba (population 1.4 million) all neurosurgical procedures and all autopsy neuropathology examinations are done at one center. In a retrospective review (1996-2025) I searched for cases with pituitary inflammation. Among 678 surgical pituitary biopsies we encountered: 15 idiopathic lymphocytic hypophysitis; 18 PitNET with inflammation; 34 PitNET + apoplexy with inflammation; 13 inflammation associated with Rathke cleft cyst; 3 bacterial infection. Among 4768 pituitaries from autopsies we encountered: 16 idiopathic lymphocytic hypophysitis; 1 PitNET + apoplexy; 2 pituitary apoplexy without obvious cause; 3 inflammation associated with Rathke cleft cyst; 19 pituitary inflammation and associated disseminated infection (2 Herpes simplex; 5 suspected viral; 5 Mycobacterial; 7 other bacterial sepsis / meningitis). In some autopsy cases lymphocytic hypophysitis was incidental, 1 had chronic demyelinating disease, 4 had prominent inflammation in the thyroid, and in 1 case it was considered to be a major contributor to death. Four decedents had pre-mortem clinical endocrine syndrome (38 year female hypothyroidism; 49 year female hyperprolactinemia; 44 year male Addison disease and hypothyroidism; 49 year female diabetes mellitus). Conclusive proof of autoimmune lymphocytic hypophysitis is elusive. PitNET, apoplexy, and cyst-associated inflammation are common and of uncertain significance. In all specimens, complete history and imaging correlates are necessary. Although rarely a contributor to death, examination of the pituitary gland is an important part of the autopsy in individuals who die unexpectedly, particularly if they have a history of endocrine disease or recent neurological symptoms.