What Causes GAVE Syndrome (Watermelon Stomach)
GAVE syndrome is associated with several chronic medical conditions including cirrhosis, chronic kidney disease, and systemic sclerosis, though the exact pathogenesis remains unclear and portal hypertension is not required for its development. 1
Primary Associated Conditions
The most well-established associations with GAVE include:
- Cirrhosis and liver disease – GAVE occurs in patients with cirrhosis, though importantly, about 30% of GAVE patients have portal hypertension, and it remains unclear whether portal hypertension is actually involved in GAVE development 1
- Chronic kidney disease and end-stage renal disease – GAVE is recognized as a cause of chronic gastrointestinal blood loss in dialysis patients 1, 2, 3
- Autoimmune connective tissue diseases, particularly systemic sclerosis (scleroderma) 1, 4, 3
Pathophysiology
The underlying mechanism involves:
- Dilated vessels with fibrin thrombi in the gastric mucosa 1
- Fibromuscular hyperplasia of the lamina propria 1, 3
- Possible mechanical stress on submucosal vessels due to antropyloric peristaltic motility dysfunction, modulated by neurohormonal vasoactive alterations 5
Important Distinction from Portal Hypertensive Gastropathy
GAVE must be distinguished from portal hypertensive gastropathy (PHG), as these are separate entities with different treatments. 1, 5 While PHG requires portal hypertension and causes diffuse gastric mucosal changes with a snake-skin or mosaic pattern, GAVE:
- Can occur independently of portal hypertension 1
- Has characteristic linear red stripes (resembling watermelon stripes) or diffuse erythematous patches on endoscopy 4, 3
- Shows specific histologic features of vascular ectasia with fibrin thrombi 1, 3
Additional Risk Factors and Associations
- Iatrogenic causes: Imatinib mesylate (tyrosine kinase inhibitor) has been reported as a cause of GAVE 5
- Cardiovascular disease 6
- Idiopathic cases: Many patients have no identifiable associated condition 4
Clinical Pitfall
The endoscopic appearance of GAVE can be misdiagnosed as "gastritis" or confused with portal hypertensive gastropathy if not carefully examined 4, 5. Gastric biopsy showing vascular ectasia without inflammation helps confirm the diagnosis 4.
Emerging Evidence on Autoimmune Etiology
Recent case reports suggest autoimmune mechanisms may play a role, as demonstrated by complete mucosal healing with azathioprine treatment, supporting an autoimmune component to GAVE pathogenesis 6.