Department of Gastroenterology and Hepatology, Federation of National Public Service Personnel Mutual Aid Associations Meijo Hospital, Nagoya, Japan,
Department of Gastroenterology and Hepatology, Nagoya University Graduate School of Medicine, Nagoya, Japan,
Intervirology. 2019;62(1):23-29. doi: 10.1159/000499691. Epub 2019 Jun 17.
The incidence of mixed hepatitis C virus (HCV) genotype infection is variable, and a few reports exist regarding the efficacy of direct-acting antivirals (DAA) therapy for mixed genotype. We aimed to investigate the prevalence of mixed genotype and its impact on the virologic response to DAA therapy.
A total of 365 patients with chronic HCV infection who completed antiviral therapy were recruited. Nested polymerase chain reaction with universal and specific primers of genotypes 1b and 2 and direct sequencing were used for HCV genotyping.
Direct sequencing with universal primers defined genotypes 1b (n = 230), 2a (n = 95), and 2b (n = 40). Direct sequencing of genotype 2 was performed in patients with genotype 1b, and direct sequencing of genotype 1b in patients with genotype 2. Four patients with genotype 1b underwent amplification for genotype 2, and direct sequencing identified genotypes 1b (n = 1), 2a (n = 1), and 2b (n = 2). None with genotype 2 underwent amplification for genotype 1b. Three cases were confirmed to have mixed genotype.
Mixed genotype was rare, and hence the impact of mixed genotype on treatment outcome with DAA therapy is expected to be minimal.
混合丙型肝炎病毒（HCV）基因型感染的发生率各不相同，有少数关于直接作用抗病毒药物（DAA）治疗混合基因型疗效的报告。我们旨在研究混合基因型的流行情况及其对 DAA 治疗病毒学应答的影响。
共招募了 365 名完成抗病毒治疗的慢性 HCV 感染患者。使用通用和特定于基因型 1b 和 2 的引物进行巢式聚合酶链反应和直接测序，用于 HCV 基因分型。
通用引物的直接测序确定了基因型 1b（n = 230）、2a（n = 95）和 2b（n = 40）。对基因型 1b 患者进行基因型 2 的直接测序，对基因型 2 患者进行基因型 1b 的直接测序。4 名基因型 1b 患者进行了基因型 2 的扩增，直接测序鉴定出基因型 1b（n = 1）、2a（n = 1）和 2b（n = 2）。无基因型 2 患者进行了基因型 1b 的扩增。确认有 3 例为混合基因型。
混合基因型罕见，因此预计混合基因型对 DAA 治疗的治疗结果影响最小。
