Katelaris P H, Nguyen T V, Robertson G J, Bradbury R, Ngu M C
Gastroenterology Unit, University of Sydney, Concord Hospital, NSW.
Aust N Z J Med. 1998 Oct;28(5):633-8. doi: 10.1111/j.1445-5994.1998.tb00660.x.
The pre-treatment sensitivity of Helicobacter pylori to metronidazole is a key determinant of successful eradication therapy and should influence local choice of therapy. However, there are few data defining the prevalence of metronidazole resistance (MR) in Australia.
To determine prospectively the prevalence and demographic determinants of MR in H. pylori isolates from a large and cosmopolitan cohort of dyspeptic patients in Sydney.
Consecutive dyspeptic patients undergoing endoscopy had gastric biopsies for histology, urease test and culture. Metronidazole resistance was determined by E-test after subculture. An MIC > 8 micrograms/mL defined MR. Patient age, gender, birthplace and history of previous nitroimidazole use were recorded.
In 732 patients, H. pylori was present in 46.4%. Culture was successful in 81% and subculture for MR in 88% of these. In 237 evaluable patients the overall MR rate was 59.1%. Five patients had had prior triple therapy for H. pylori (of which four of five had MR). Therefore, the primary MR rate in the study population was 58.6% (136/232). MR was more prevalent in younger patients (p = 0.0002). The MR rate was 70.4% in patients 18-39 years, 66.7% in those aged 40-59 years and lowest (38.9%) in those 60 years or older (p = 0.002). The MR rate was highest in patients born in Southeast Asia (72.8%, 59/81) and significantly higher than in Australian born (48.1%, 26/54), or Southern European (46.2%, 24/52) born patients (p = 0.002). There was no gender difference. Logistic regression to determine the impact of each variable (birthplace, age and gender) on MR identified Southeast Asia birthplace as a factor associated with greater likelihood of harbouring an MR isolate (OR 1.88, p = 0.02). Southern European born patients had the lowest risk of MR (OR 0.70, p = 0.02) as did patients older than 60 years (OR 0.56, p = 0.04). A definite history of prior metronidazole use was infrequent and not predictive of MR.
While a high rate of MR is not unexpected in patients born in developing countries, the high rate in Australian born patients is surprising and of concern. This may relate to the high local usage of nitroimidazoles as monotherapy and has important implications for the effectiveness of metronidazole containing triple therapies.
幽门螺杆菌对甲硝唑的治疗前敏感性是根除治疗成功的关键决定因素，应影响当地治疗方案的选择。然而，关于澳大利亚甲硝唑耐药（MR）的流行情况的数据较少。
前瞻性地确定悉尼一大群消化不良患者中幽门螺杆菌分离株的MR流行情况及其人口统计学决定因素。
连续接受内镜检查的消化不良患者进行胃活检以进行组织学检查、尿素酶试验和培养。亚培养后通过E试验确定甲硝唑耐药性。最低抑菌浓度（MIC）>8微克/毫升定义为MR。记录患者的年龄、性别、出生地和既往使用硝基咪唑的病史。
732例患者中，幽门螺杆菌感染率为46.4%。81%的培养成功，其中88%的培养物用于MR亚培养。在237例可评估患者中，总体MR率为59.1%。5例患者曾接受过幽门螺杆菌三联疗法（其中5例中有4例有MR）。因此，研究人群中的原发性MR率为58.6%（136/232）。MR在年轻患者中更为普遍（p = 0.0002）。18 - 39岁患者的MR率为70.4%，40 - 59岁患者为66.7%，60岁及以上患者最低（38.9%）（p = 0.002）。出生在东南亚的患者MR率最高（72.8%，59/81），显著高于澳大利亚出生的患者（48.1%，26/54）或南欧出生的患者（46.2%，24/52）（p = 0.002）。无性别差异。通过逻辑回归确定每个变量（出生地、年龄和性别）对MR的影响，发现东南亚出生地是携带MR分离株可能性更大的一个因素（比值比1.88，p = 0.02）。南欧出生的患者MR风险最低（比值比0.70，p = 0.02），60岁以上患者也是如此（比值比0.56，p = 0.04）。既往明确使用过甲硝唑的病史并不常见，也不能预测MR。
虽然在发展中国家出生的患者中MR率较高并不意外，但澳大利亚出生的患者中MR率较高令人惊讶且令人担忧。这可能与当地硝基咪唑作为单一疗法的高使用率有关，并且对含甲硝唑三联疗法的有效性具有重要意义。
