Spontaneous bacterial empyema in patients with liver cirrhosis in Upper Egypt: prevalence and causative organisms

Abstract

Background: Spontaneous bacterial empyema (SBEM) is a complication in cirrhotic patients, in which a preexisting pleural effusion becomes infected.

Purpose: The purpose was to determine the prevalence and causative organisms of SBEM among cirrhotic patients with hydrothorax.

Materials and methods: This descriptive, cross-sectional study included 901 cirrhotic patients. All patients underwent clinical evaluation, liver function tests, chest X-ray, abdominal and chest ultrasonography, and pleural and peritoneal fluids study (when detected) including polymorphonuclear (PMN) leukocyte count, biochemical analysis, and culture by two methods: conventional and modified (inoculation of 10 mL of pleural or peritoneal fluid into a blood culture bottle). Diagnostic criteria for SBEM included positive pleural fluid culture and a PMN count of >250 cells/mm(3) or, if a negative culture, a pleural fluid PMN count of >500 cells/mm(3) and the absence of pneumonia on chest radiography.

Results: Of 901 cirrhotic patients, 16 cases of SBEM were diagnosed. The prevalence of SBEM was 1.8 % in cirrhotic patients and 26.2 % in patients with cirrhosis and hydrothorax. Pleural fluid culture was found to be positive by the conventional method in four (25 %) cases and by modified methods in 11 (68.8 %) cases. Escherichia coli was the most frequently isolated pathogen (six cases). The mortality rate of SBEM was 25 %.

Conclusions: SBEM is a frequent complication in cirrhotic patients with hydrothorax. E. coli is the most frequent organism responsible for SBEM. The modified method of pleural fluid culture is more sensitive than the conventional method for diagnosis of SBEM.

Keywords: Cirrhosis; Hydrothorax; Spontaneous bacterial empyema (SBEM).