Bedside diagnosis of spontaneous bacterial peritonitis using reagent strips

Abstract

Objective: To determine the efficacy of reagent strip for bedside diagnosis of spontaneous bacterial peritonitis (SBP).

Design: Cross-sectional analytical study.

Place and duration of study: Shaikh Zayed Postgraduate Medical Institute from November 2003 to August 2004.

Patients and methods: Patients with cirrhosis and ascites underwent diagnostic paracentesis. Fluid was checked for leukocyte esterase released by PMN by using Combur 10 urine strip and graded for color change from 0-3. Fluid was also analyzed by cytology for PMN count. Results of both methods were compared to determine sensitivity, specificity and accuracy of strip for diagnosis of SBP.

Results: Of 214 paracentesis performed, SBP was diagnosed in 38 patients whereas 176 were negative for infection. Strip test was 97.7% sensitive and 89.4% specific with positive predictive value of 90%, negative predictive value of 97.7% and accuracy of 96.2%, when reagent strip grade 3 was considered as positive for diagnosis.

Conclusion: Reagent strip is a quick bedside test, highly sensitive and specific for the diagnosis of SBP, based on polymorphonuclear count in ascitic fluid, to initiate early treatment, thus improving patient's outcome.