A 60-year-old man with decompensated cirrhosis presents with fever (38.9°C), abdominal pain, and worsening confusion. Vital signs show BP 92/58, HR 108, RR 22, SpO2 98% on room air. Physical examination reveals tense ascites but no focal peritoneal signs. Diagnostic paracentesis yields turbid fluid with neutrophil count of 420 cells/mm³, total protein 1.2 g/dL, and negative bacterial culture. He denies recent antibiotic use. Which diagnosis best explains these findings?

1. A)Spontaneous bacterial peritonitisGABARITO
2. B)Budd-Chiari syndrome
3. C)Perforated duodenal ulcer
4. D)Primary sclerosing cholangitis
5. E)Acute pancreatitis