Purpose: Endocarditis in cirrhotic patients is known to cause increased mortality and morbidity. We report a case of a cirrhotic patient who was thought to have SBP refractory to antibiotic treatments but was later found to have mitral valve aneurysm and endocarditis. Methods: A 55-year-old male with Hep C cirrhosis and IV drug abuse presented with altered mental status and abdominal pain. The patient was a cachectic, alert and oriented to location and person only. He had an admission a month earlier to another hospital for SBP and completed a course of antibiotics. Physical examine showed mild asterixis, tachycardia, no murmur, abdominal distention, tense ascites, and caput medusa. Results: Labs showed hemoglobin of 11.6g/dL, WBC 8.7K/mcl. Ascitic fluid showed WBC 20875/cumm, and RBC 200/cumm, poly 95%, glucose 35mg/dL, protein 4.7g/dL. Blood culture was positive for pansensitve enterococcus faecalis. Patient was inititally treated with cefotaxime, ampicillin and flagyl for SBP. After he failed to improve clinically, a repeat paracentesis was done 6 days later. It showed WBC 22000/cumm, and RBC 4800/cumm, poly 95%. Gram stain, culture, TB culture, amylase and cytology were negative. As there was nothing to indicate a surgical abdomen on physical exam, CT abdomen was done which showed loculations of ascitic fluid likely abscess, and vascular thrombosis of the spleen. Repeat blood culture continued to show pansensitive enterococcus faecalis. A transthoracic echo was done and showed aneurysmal mitral valve lesion with vegetations. The patient was started on gentamyin and ampicillin for endocarditis. He also had IR guided drainage of the abscess with a 15L drainage from the abdomen. Patient's clinical condition improved with multiple negative blood and ascitic cultures thereafter. However, he left against medical advice 3 weeks after treatment. Conclusion: Cirrhotic patients are more susceptible to various infections and bacteremia due to changes in the endothelial system, decreased opsonic activity, leukocyte dysfunctions, and iatrogenic factors. Large number of autopsy series and multiple retrospective studies have shown increased incidences of endocarditis in cirrhotic patients compared to noncirrhotics, and also with a higher mortality rate. Our case is a rare presentation of what was thought to be severe SBP but was instead endocarditis causing peritoneal abscess. This is important as endocarditis has a mortality rate of 20-30%, with a recurrence rate of 5%, which maybe even higher in cirrhotics. However, it is rarely promptly diagnosed since it is often masked by SBP or other types of infection.