Usefulness of reagent strips for checking cure in spontaneous bacterial peritonitis after short-course treatment

P>Background The usefulness of reagent strips to check cure of spontaneous bacterial peritonitis have not been evaluated to date. Aim To assess the usefulness of ascitic fluid analysis by means of reagent strips to check cure after a 5-day antibiotic course. Methods We prospectively included all cirrhotic patients diagnosed with spontaneous bacterial peritonitis. On day 5, conventional and reagent strip ascitic fluid analyses were performed. Results Fifty-three episodes of spontaneous bacterial peritonitis in 51 cirrhotic patients were included. Five patients died before the fifth day and in two patients, the control paracentesis yielded no ascitic fluid. In nine out of 46 cases (19.6%), spontaneous bacterial peritonitis had not resolved by day 5. In 32 out of 33 cases in which the ascitic fluid polymorphonuclear count was < 250/mu L at day five, the reagent strips was negative. The negative predictive value of the reagent strip at fifth day was 97% and the LR- 0.13. Conclusions Almost 20% of episodes of spontaneous bacterial peritonitis do not resolve with a short-course of antibiotic treatment. In view of the high negative predictive value and low likelihood ratio for a negative test, reagent strips analysis may be an alternative to conventional cytology if a 5-day antibiotic therapy is planned.