Superior mesenteric arteriovenous fistula as a rare manifestation of Cowden syndrome: A case report and review of literature

Table 3 Timeline of clinical presentation, diagnosis, and management

Time point	Clinical presentation and diagnostic/therapeutic interventions	Key findings and clinical decisions
Day 0	A 50-year-old woman presented with progressive abdominal distension for more than 6 months	Physical examination revealed a markedly protuberant abdomen, with positive shifting dullness, consistent with massive ascites
Day 1	Laboratory testing for liver function, hepatotropic viruses, autoantibodies, and ascitic fluid analysis	All markers (viral, autoimmune, and biochemical) were within normal limits. Ascites was confirmed as transudate; alcoholic and viral hepatitis were excluded
Day 2	Initial physical examination and contrast-enhanced abdominal MRI	Findings suggested possible early-stage liver cirrhosis, splenomegaly, ascites, and portal vein dilatation (18 mm)
Day 4	DSA with superior mesenteric artery angiography combined with indirect portography	Thickened and tortuous superior mesenteric artery with a distinct arteriovenous malformation; rapid flow with early visualization of mesenteric and portal veins
Day 10	TIPS and transjugular liver biopsy	Liver biopsy showed fibrous hyperplasia but no definitive evidence of cirrhosis
Day 21	Acute hematemesis followed by emergency gastroscopy	Esophagogastric varices and multiple gastric polyps identified; biopsy confirmed fundic gland polyps
Day 22	WES	PTEN mutation identified (c.80A>G/p.Tyr27Cys)
Retrospective review	Detailed retrospective analysis of past medical history	History of multiple neoplasms (endometroid adenocarcinoma, thyroid cancer, uterine leiomyoma, bilateral breast tumors) and vascular malformations (lower-extremity hemangiomas)
Final diagnosis	Integration of clinical, imaging, pathological, and genetic data	Diagnosis of CS established

DSA: Digital subtraction angiography; MRI: Magnetic resonance imaging; TIPS: Transjugular intrahepatic portosystemic shunt; WES: Whole-exome sequencing.