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/microL 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.