Evaluation of a Specific Modulation Frequency Technique for Detecting H. pylori in a Model of Experimentally Infected Mice.

ABSTRACT

Diagnosis of Helicobacter pylori is challenging. Diverse techniques have been developed for accurate diagnosis. However, they have some limitations. This research investigated the efficacy of specific modulation frequency (SMF) compared to other routine diagnostic methods for detecting H. pylori in gastric biopsy samples of experimentally infected mice. One-hundred and fifty healthy male C57BL/6 mice were included and divided into the control and treatment groups. The mice in the treatment group were treated with 0.2 ml of 0.2 M NaHCO3 to neutralize gastric acidity. Then, 109 colony-forming units of H. pylori (ATCC 43504) mixed in PBS were used intragastrically to inoculate the mice. Mice were kept for up to 28 days and examined on days 0, 7, 14, 21, and 28 using culture, polymerase chain reaction (PCR), and SMF. On day 0, only the SMF and PCR could detect the H. pylori in the stomach of 60% and 20% of mice, respectively. On day 7, culture, PCR, and SMF could detect H. pylori in 40%, 80%, and 100% of mice, respectively. SMF detected all infected mice from days 7 to 28 (100%). PCR detected all H. pylori-infected mice at days 14 to 27 (100%). Another test (culture) detected all infected mice only on day 28. Significant differences were found among the three diagnostic methods on days 0, 7, 14, and 21 of the experiment (P<0.05). SMF was found to have high sensitivity and specificity for H. pylori detection in the early stages of infection.