Use of Reagent Strips for the Rapid Diagnosis of Spontaneous Bacterial Empyema

Abstract

To assess the utility of reagent strips for rapid diagnosis of spontaneous bacterial empyema in cirrhotic patients with hepatic hydrothorax. Analysis of ascitic fluid using reagent strips is a useful diagnostic test for spontaneous bacterial peritonitis. A reagent strip for leukocyte esterase designed for the testing of urine was used to evaluate pleural fluid analysis in 47 nonselected thoracenteses in 28 cirrhotic patients with hepatic hydrothorax. Twelve spontaneous bacterial empyemas were diagnosed. Simultaneous spontaneous bacterial peritonitis was present in 7 of 10 cases in which ascites fluid was analyzed. When a test result of 3 or 4 was considered positive, sensitivity was 83% (10 of 12), specificity was 100% (35 of 35), and positive predictive value was 100%. When result of 2 or more was considered positive, sensitivity was 92% (11 of 12), specificity was 80% (28 of 35), and negative predictive value was 97%. Analysis of pleural fluid with reagent strips is a rapid, easy to use, and inexpensive tool for the diagnosis of spontaneous bacterial empyema in cirrhotic patients. A positive result should be considered an indication for antibiotic therapy.