Cell and Molecular Research Center, Qazvin University of Medical Sciences, Qazvin, Iran.
Laryngoscope. 2013 Jun;123(6):1478-82. doi: 10.1002/lary.23777. Epub 2013 Feb 12.
OBJECTIVES/HYPOTHESIS: To investigate the allelic prevalence of resistance to clarithromycin in the DNA of clinical isolates of Helicobacter pylori obtained from biopsy specimens of patients with chronic tonsillitis by Scorpion real-time polymerase chain reaction (PCR).
Pathologic specimens of patients with chronic tonsillitis were used for rapid urease test, and blocks of paraffin-embedded tonsillar tissue were used for McMullen staining, rapid urease test, and Scorpion real-time PCR test.
A total of 103 biopsy samples were obtained from patients with chronic tonsillitis and examined for the presence of clarithromycin resistant H. pylori. Modified McMullen staining and rapid urease test were done on the all the samples. The DNA of specimens was extracted from the pathology blocks, and Scorpion real-time PCR was performed on a final volume of 25 μL.
Of 103 biopsy specimens, 22 samples were identified as infected by H. pylori, of which none were sensitive to clarithromycin. One had the A2143G genotype, and four had the A2142G genotype. Two had a mixed sensitive and the A2143G genotype, and five had a mixed sensitive and A2142G genotype. One strain had a mixed genotype of sensitive, A2143G, and A2142G.
The reported rate of resistance to clarithromycin is of great variation among H. pylori strains isolated from specimens in different countries. Our study showed that the most prevalent genotypes in our H. pylori-positive specimens was A2142G followed by A2143G, which is different from reported results of allele-specific genotyping of H. pylori strains isolated from gastric biopsy and may be a result of cross-resistance to erythromycin and other macrolides.
目的/假设：通过蝎式实时聚合酶链反应（PCR）检测从慢性扁桃体炎患者活检标本中分离的幽门螺杆菌临床分离株的 DNA 中克拉霉素耐药的等位基因流行率。
将慢性扁桃体炎患者的病理标本用于快速尿素酶试验，并用石蜡包埋扁桃体组织块进行 McMullen 染色、快速尿素酶试验和蝎式实时 PCR 试验。
从慢性扁桃体炎患者中获得 103 个活检样本，用于检测是否存在克拉霉素耐药的 H. pylori。对所有样本均进行改良 McMullen 染色和快速尿素酶试验。从病理块中提取标本的 DNA，在最终体积为 25μL 的情况下进行蝎式实时 PCR。
在 103 个活检标本中，22 个样本被鉴定为感染了 H. pylori，其中没有一个对克拉霉素敏感。其中一个有 A2143G 基因型，四个有 A2142G 基因型。两个有敏感和 A2143G 基因型的混合，五个有敏感和 A2142G 基因型的混合。一个菌株具有敏感、A2143G 和 A2142G 的混合基因型。
在不同国家从不同标本中分离的 H. pylori 菌株对克拉霉素的耐药率报道差异很大。我们的研究表明，在我们的 H. pylori 阳性标本中最常见的基因型是 A2142G，其次是 A2143G，这与从胃活检标本中分离的 H. pylori 菌株的等位基因特异性基因分型报道结果不同，可能是由于对红霉素和其他大环内酯类药物的交叉耐药性所致。
