Serum Complement 3 Level and Culture Positivity As Predictors Of Spontaneous Bacterial Peritonitis Recurrence In Egyptian Cirrhotic Patients

Background: Spontaneous bacterial peritonitis (SBP) is one of the most common and life threatening complications of cirrhosis. The risk of SBP recurrence is around 70% per year. Altered host immune system and presence of infection are thought to be the basis for its recurrence. Objective: To study serum complement 3 level and culture positivity as predictors of SBP recurrence in Egyptian cirrhotic patients. Patients &Methods: This study was carried out at Faculty of Medicine, Zagazig University, Egypt. It is a prospective case-control study in which we recruited 160 cirrhotic ascitic patients presenting with SBP. Any episode of SBP after resolution of the first index case of SBP within 6months was considered as recurrence. They were divided after follow up for 6 months to detect recurrence into two groups; Group I: 79 cirrhotic ascitic patients without recurrent SBP (control group) and Group II : 71 cirrhotic ascitic patients with recurrent SBP (cases group). All patients were subjected to full history taking, general and local abdominal examinations and ultrasonographic examination. In addition, they were subjected to routine laboratory investigations, ascitic fluid (AF) analysis and culture and serum complement C3 level assay Results: In the current study, there was 71 of 150 (47.3%) patients developed recurrent SBP. Recurrent SBP developed in patients with total bilirubin >1.2 mg/dL (p < 0.001), serum albumin < 3.5 g/dL (p < 0.001), SGOT > 35 IU/L (p < 0.032), ascitic protein <1 gm/dL (p < 0.001), PT >18 seconds (p < 0.001) and AF polymorphonuclear leucocyte count < 250 cell/ mm3 (p < 0.001), serum C3 <90 mg/dL (p < 0.001) and positive culture of ascitic fluid (p < 0.001). Multivariate logistic regression analysis for the most predictor variables of recurrent SBP among the studied patients were decreased serum C3, positive culture, increased total bilirubin, decreased serum albumin, decreased AF protein and prolonged PT. Conclusion: Recurrent SBP was noticed in 47.3% of Egyptian cirrhotic patients. Serum C3 <90 mg/dl and positive culture were significant factors associated with recurrent SBP in Egyptian cirrhotic patients.