Effect of trimethoprim-sulfamethoxazole vs. norfloxacin on fecal E. coli resistance pattern and efficacy in patients receiving prophylaxis for spontaneous bacterial peritonitis

Abstract

Background: Spontaneous Bacterial Peritonitis (SBP) is an infection of ascitic fluid. It is highly mortal and recurrent condition, so prophylaxis with Norfloxacin (NOR) or Trimethoprim-sulfamethoxazole (TMP-SMX) seems to play an important role in the prevention of further episodes of SBP. Aims of the study were to assess the effect of TMP-SMX/NOR on the sensitivity pattern of fecal E. coli after long term prophylaxis in Spontaneous Bacterial Peritonitis (SBP) and to compare the efficacy of TMP-SMX and NOR in prophylaxis of SBP.Methods: An interventional, prospective, open label, single center study conducted in Maulana Azad medical college, New Delhi, India. 52 patients of SBP or with high risk of SBP were screened and finally 39 patients were recruited. Stool sensitivity testing of fecal E. coli was done and they were divided into TMP-SMX group(n=18) and NOR group(n=21) according to sensitivity. After 45±3 days (7 weeks) their stool sample was re-examined for change sensitivity pattern of E. coli. Efficacy variables like any episode of SBP, fever (FEV) resolution of ascites (ASC), bacteremia (BACT), extraperitoneal infection (EPI), liver transplantation (LT) or death (D) were noted throughout the period of 24 weeks.Results: Resistance developed in 60% vs. 48% in TMP-SMX vs. NOR group(p=0.46) after 45 days of prophylaxis. By the end of 24 weeks, Incidence of SBP (29%vs. 25%, p>0.99), episodes of FEV(P=0.60), EPI(p>0.99), ASC(p>0.99) and death (14% vs. 16%, p>0.99) were almost similar in both the groups (TMP-SMX vs. NOR) respectively.Conclusions: Both TMP-SMX and NOR showed same degree of resistance and found equi-efficacious when administered as long-term prophylactic therapy in SBP. TMP-SMX can be a suitable as well as cost effective alternative to NOR for the prophylaxis of SBP.