Universidade Federal do Ceará, Faculdade de Medicina, Programa de Pós-Graduação em Ciências Médico-Cirúrgicas, Fortaleza, Ceará, Brazil.
Hospital do Câncer de Barretos, Centro de Pesquisa em Oncologia Molecular, Barretos, São Paulo, Brazil.
Rev Inst Med Trop Sao Paulo. 2022 Jul 13;64:e47. doi: 10.1590/S1678-9946202264047. eCollection 2022.
The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori's primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment.
幽门螺杆菌对克拉霉素耐药性的增加令人担忧。本研究评估了成人消化不良患者和无症状儿童中幽门螺杆菌对克拉霉素的原发耐药率及其与毒力因子的相关性。纳入了患者（153 例胃炎、24 例胃癌、21 例消化性溃疡）的胃黏膜和通过丝线试验从 24 例幽门螺杆菌和 23S rRNA 阳性无症状儿童获得的胃液。通过 TaqMan RT-PCR 23S rRNA 点突变 A2142G 和/或 A2143G 评估克拉霉素耐药性，并通过 PCR 评估幽门螺杆菌毒力标志物。总体而言，克拉霉素耐药率为 14.4%（32/222），成人耐药率为 14.2%，儿童耐药率为 12%，而来源、性别和疾病无显著差异。最常见的点突变是 A2143G（62.5%）。cagA 阳性菌株（11.4%）的点突变明显少于 cagA 阴性菌株（23.6%）（p=0.03 OR=0.495%CI=0.19-0.91）和 cagE 阳性菌株（10.2%）、cagE 阴性菌株（21.2%）（p=0.03 OR：0.4 IC：0.20-0.91）。iceA 或 vacA 等位基因基因型无差异。克拉霉素原发耐药率低于巴西东南部报道的耐药率。cagA 和 cagE 阳性的幽门螺杆菌样本点突变较少，提示感染毒力株的个体可能对抗幽门螺杆菌治疗更敏感。
