Comparision of fluorescent in situ hybridization and rapid diagnostic methods on helicobacter pylori diagnosis, and detection of accompanying clarithromycin resistance

Helicobacter pylori, is a spiral shaped gram-negative, microaerophilic bacterium which coloni?s gastric mucosa. The infected population with H. pylori prevalence rate is 50 % in developed countries and over 90 % in developing countries. Persistent infection induces peptic ulcer and chronic gastritis and has also been associated with gastric cancer and mucosal associated lymphoid tissue lymphoma. The accurate detection of the organism is essential for proper patient management and particularly for the eradication of the bacteria following treatment. There have been many invasive (histopathological diagnosis, culture, urease tests, molekular testler) and noninvasive methods (urea breath test, serological tests, HpSA) for the detection of H. pylori. Although some of the invasive methods are still accepted for the primary diagnosis in symptomatic patients, noninvasive methods are much more utilized in practice easier to perform. This study was carried out with 147 patients (%61.9 females; mean age 45.2 ± 14.9) who has taken antral biopsy. FISH and HpSA examinations were made on 133 and 122 samples respectively. The presence of clarithromycin resistance investigated with FISH and agar dilution methods. A total of 61 (41.5%) biopsy samples were positive for culture and 67 (54.9%) stool samples were positive with HpSA. FISH and PCR positivity rates were found 61.7% (82) and 73.5% (108) respectively. Clarithromycin resistance was detected 11.6% with agar dilution and 24.4% with FISH. In our study on H. pylori, we have evaluated the sensitivity and spesivity of the FISH method as 72.5% and 74.1% respectively. Our study suggests that the FISH method can be used in the diagnosis of H pylori infections and for detecting clarithromycin resistance as a rapid, sensitive and simple method to support other diagnostic tools.