Evaluation of leukocyte esterase reagent strip test to detect spontaneous bacterial peritonitis in cirrhotic patients

Spontaneous bacterial peritonitis (SBP) is a frequent and sever complication of cirrhotic patients with ascites. The aim of this study was to assess diagnostic value of leukocyte esterase reagent strip test (Medi-Test Combi) for the rapid diagnosis of SBP in cirrhotic patients with ascites in the University Hospital of Imam Reza in Tabriz, Iran. In this study, 132 consecutive samples from cirrhotic patients who underwent abdominal paracentesis were evaluated. These samples were tested by 3 methods: i) manual cell count with differential study, SBP was defined as having poly-morphonuclear cells count of ≥250/mm3; ii) culture of ascetic fluid samples; iii) all samples were tested by leukocyte esterase dipsticks. The sensitivity, specificity, positive and negative predictive values of two different colorimetric cut-off scales (1+ and 2+) were calculated and compared. The sensitivity, specificity, positive and negative predictive values of 1+ and 2+ cut-off scales to diagnose SBP were 97.5%, 84.6%, 74% and 98.7% for the 1+ cut-off scale and 87.8%, 96.7%, 92.3% and 94.6% for the 2+ cut-off scale. Leukocyte esterase reagent strip test can be used as a rapid test for screening of SBP. The higher cut-off colorimetric scale has a better specificity and positive predictive value but a lower sensitivity.