Add comprehensive articles on Vascular Dementia and Wallerian Degeneration

- Created a detailed article for Vascular Dementia covering key facts, terminology, imaging findings, differential diagnoses, pathology, clinical issues, and diagnostic checklist. - Developed an extensive article on Wallerian Degeneration including key facts, terminology, imaging features, differential diagnoses, pathology, clinical issues, and diagnostic checklist.
2025-10-17 22:11:27 +01:00
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+---
+title: "Lymphocytic Hypophysitis"
+docid: "f30774c3-cbd0-4ab3-b3d1-e0574106db1f"
+breadcrumbs:
+  - "Brain"
+  - "Diagnosis"
+  - "Anatomy-Based Diagnoses"
+  - "Sella and Pituitary"
+  - "Miscellaneous"
+  - "Lymphocytic Hypophysitis"
+---
+# KEY FACTS
+
+- ## Terminology
+  
+  
+    - Lymphocytic hypophysitis (LH)
+    - Synonyms: Adenohypophysitis, primary hypophysitis, stalkitis
+    - Idiopathic inflammation of pituitary gland &/or stalk
+- ## Imaging
+  
+  
+    - Thick stalk (> 2 mm + loss of normal "top to bottom" tapering)
+    - ± enlarged pituitary gland
+    - 75% show loss of posterior pituitary "bright spot"
+    - Enhances intensely, uniformly
+    - May have adjacent dural or sphenoid sinus mucosal thickening
+- ## Top Differential Diagnoses
+  
+  
+    - Macroadenoma
+    - Pituitary hyperplasia
+    - Adolescent pituitary gland
+    - Granulomatous disease
+    - Ectopic posterior pituitary gland
+- ## Clinical Issues
+  
+  
+    - Autoimmune, inflammatory disorder; other etiologies: Granulomatous disease, IgG4 disease or drug related
+    - Peripartum woman with headache, multiple endocrine deficiencies
+    - Middle-aged man with diabetes insipidus (lymphocytic infundibuloneurohypophysitis)
+    - Mean in women = 35 years, men = 45 years
+    - M:F = 1:8-9
+    - Often self-limited
+    - Unrecognized, untreated LH can result in death from panhypopituitarism
+    - Conservative care (steroids, hormone replacement)
+- ## Diagnostic Checklist
+  
+  
+    - LH can mimic pituitary adenoma
+
+# TERMINOLOGY
+
+- ## Abbreviations
+  
+  
+    - Lymphocytic hypophysitis (LH)
+- ## Synonyms
+  
+  
+    - Adenohypophysitis, primary hypophysitis, stalkitis
+- ## Definitions
+  
+  
+    - Idiopathic inflammation of pituitary gland or stalk
+
+# IMAGING
+
+- ## General Features
+  
+  
+    - ### Best diagnostic clue
+      
+      
+          - Thick, nontapered stalk, ± pituitary mass
+    - ### Location
+      
+      
+          - Suprasellar, intrasellar
+    - ### Size
+      
+      
+          - Usually < 10 mm but may reach 2-3 cm
+    - ### Morphology
+      
+      
+          - Rounded pituitary gland with infundibulum that appears thickened, nontapering, or bulbous
+- ## MR Findings
+  
+  
+    - ### T1WI
+      
+      
+          - Thick stalk (> 2 mm + loss of normal tapering)
+          - ± enlarged pituitary gland
+          - 75% show loss of posterior pituitary "bright spot"
+    - ### T2WI
+      
+      
+          - Iso-/hypointense
+    - ### T1WI C+
+      
+      
+          - Enhances intensely, uniformly
+          - May see dural or sphenoid sinus mucosal thickening
+- ## Imaging Recommendations
+  
+  
+    - ### Best imaging tool
+      
+      
+          - MR
+    - ### Protocol advice
+      
+      
+          - MR: Precontrast thin-section (< 3 mm) sagittal, coronal T1 and T2
+          - Coronal dynamic T1 C+ (may show delayed pituitary enhancement)
+
+# DIFFERENTIAL DIAGNOSIS
+
+- [Macroadenoma](/document/pituitary-macroadenoma/14ebde13-80bb-4c4e-833c-fcc6c992d47c)
+    - Sellar and suprasellar mass
+    - Sella turcica enlarged/eroded
+    - Diabetes insipidus common in LH, rare with adenoma
+- [Pituitary Hyperplasia](/document/pituitary-hyperplasia/9696bc9e-f00b-4fa7-aa67-f039efd8fbed)
+    - Stalk usually normal
+          - In young female patients, late pregnancy/peripartum
+    - May be seen with hypothyroidism, Addison disease, end-organ failure, neuroendocrine neoplasms
+- ## Adolescent Pituitary
+  
+  
+    - Enlarged gland with uniform enhancement
+- ## Granulomatous Disease
+  
+  
+    - Sarcoid, Langerhans cell histiocytosis (LCH), granulomatosis with polyangiitis; systemic disease often present
+- ## Pituitary "Dwarf"
+  
+  
+    - Stalk may appear short and stubby
+- ## Ectopic Posterior Pituitary
+  
+  
+    - Hyperintense focus at tuber cinereum or truncated stalk
+
+# PATHOLOGY
+
+- ## General Features
+  
+  
+    - ### Etiology
+      
+      
+          - Autoimmune, inflammatory disorder
+          - Other types of hypophysitis include
+                  - Granulomatous (sarcoid, LCH, infectious, etc.)
+                  - IgG4-related hypophysitis
+                  - Drug-related [cancer immunotherapy (e.g., ipilimumab)]
+- ## Gross Pathologic & Surgical Features
+  
+  
+    - Diffusely enlarged stalk/pituitary gland
+- ## Microscopic Features
+  
+  
+    - Acute
+          - Dense infiltrate of B/T lymphocytes, plasma cells, occasionally eosinophils; ± lymphoid follicles
+          - No granulomas, giant cells, or organisms; no neoplasm
+    - Chronic may demonstrate extensive fibrosis
+
+# CLINICAL ISSUES
+
+- ## Presentation
+  
+  
+    - ### Most common signs/symptoms
+      
+      
+          - Headache, visual impairment
+    - ### Clinical profile
+      
+      
+          - Peripartum woman with headache, multiple endocrine deficiencies
+          - Middle-aged man with diabetes insipidus (lymphocytic infundibuloneurohypophysitis)
+- ## Demographics
+  
+  
+    - ### Age
+      
+      
+          - Mean in women = 35 years, men = 45 years
+    - ### Sex
+      
+      
+          - M:F = 1:8-9
+    - ### Epidemiology
+      
+      
+          - Rare (1-2% of sellar lesions)
+- ## Natural History & Prognosis
+  
+  
+    - Often self-limited
+    - Unrecognized, untreated LH can result in death from panhypopituitarism
+- ## Treatment
+  
+  
+    - Conservative (steroids, hormone replacement)
+
+# DIAGNOSTIC CHECKLIST
+
+- ## Image Interpretation Pearls
+  
+  
+    - LH can mimic pituitary adenoma
+
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