Therapeutic efficacy of amoxicillin and rifaximin in patients with small intestinal bacterial overgrowth and Helicobacter pylori infection

Introduction
Small intestinal bacterial overgrowth (SIBO) may coexist with Helicobacter pylori infection, which can be the cause of chronic gastrointestinal complaints.

Aim
Evaluation of the therapeutic efficacy of amoxicillin and rifaximin in the treatment of these diseases.

Material and methods
The lactulose hydrogen breath test (LHBT) and the urea breath test (¹³C-UBT) were performed in 116 patients. In 62 patients the coexistence of small intestinal bacterial overgrowth and H. pylori infection was observed. Then, in group I (n = 30) pantoprazole (2 × 40 mg), amoxicillin (2 × 1000 mg) and metronidazole (2 × 500 mg) and in group II (n = 32) pantoprazole and amoxicillin at the above doses and rifaximin (3 × 400 mg) were administered for 10 days. After 6 weeks, both breath tests were repeated and the degree of remission of symptoms was measured using a 10-point visual analog scale (VAS).

Results
After the treatment the LHBT index decreased in group I from 61.2 ±19.4 ppm to 22.0 ±8.2 ppm (p < 0.001) and in group II from 59.6 ±15.5 ppm to 15.2 ±8.6 ppm (p < 0.001). Eradication of H. pylori (¹³C-UBT below 4.0‰) was achieved in 63.3% of patients in group I and 59.4% in group II (p > 0.05). The decrease of pain below 3.0 points in the VAS was obtained in 64.8% of patients in group I and in 56.2% in group II.

Conclusions
Combination of amoxicillin and rifaximin may be effective in the treatment of patients with small intestinal bacterial overgrowth syndrome and concomitant H. pylori infection.