Unit of Cancer Epidemiology, C.E.R.M.S., University of Turin, Turin, Italy.
PLoS One. 2009 Dec 2;4(12):e8128. doi: 10.1371/journal.pone.0008128.
Occult Hepatitis C virus (HCV) infection is a new pathological entity characterized by presence of liver disease and absence or very low levels of detectable HCV-RNA in serum. Abnormal values of liver enzymes and presence of replicative HCV-RNA in peripheral blood mononuclear cells are also observed. Aim of the study was to evaluate occult HCV occurrence in a population unselected for hepatic disease.
METHODOLOGY/PRINCIPAL FINDINGS: We chose from previous epidemiological studies three series of subjects (n = 276, age range 40-65 years) unselected for hepatic disease. These subjects were tested for the presence of HCV antibodies and HCV-RNA in plasma and in the peripheral blood mononuclear cells (PBMCs) by using commercial systems. All subjects tested negative for HCV antibodies and plasma HCV-RNA and showed normal levels of liver enzymes; 9/276 patients (3.3%) were positive for HCV-RNA in PBMCs, identifying a subset of subjects with potential occult HCV infection. We could determine the HCV type for 8 of the 9 patients finding type 1a (3 patients), type 1b (2 patients), and type 2a (3 patients).
The results of this study show evidence that occult HCV infection may occur in a population unselected for hepatic disease. A potential risk of HCV infection spread by subjects harbouring occult HCV infection should be considered. Design of prospective studies focusing on the frequency of infection in the general population and on the clinical evolution of occult HCV infection will be needed to verify this unexpected finding.
隐匿性丙型肝炎病毒（HCV）感染是一种新的病理实体，其特征为存在肝脏疾病和血清中检测不到或极低水平的 HCV-RNA。也观察到肝酶的异常值和外周血单核细胞中复制性 HCV-RNA 的存在。本研究的目的是评估未选择肝脏疾病的人群中隐匿性 HCV 的发生情况。
方法/主要发现：我们从以前的流行病学研究中选择了三个未选择肝脏疾病的受试者系列（n=276，年龄范围 40-65 岁）。使用商业系统检测这些受试者血浆和外周血单核细胞（PBMC）中 HCV 抗体和 HCV-RNA 的存在情况。所有受试者 HCV 抗体和血浆 HCV-RNA 检测均为阴性，肝酶水平正常；9/276 例患者（3.3%）在 PBMC 中 HCV-RNA 阳性，确定了具有潜在隐匿性 HCV 感染的亚组受试者。我们对 9 例患者中的 8 例确定了 HCV 类型，发现 1a 型（3 例）、1b 型（2 例）和 2a 型（3 例）。
本研究结果表明，隐匿性 HCV 感染可能发生在未选择肝脏疾病的人群中。应考虑携带隐匿性 HCV 感染的受试者传播 HCV 感染的潜在风险。需要设计前瞻性研究，重点关注一般人群中的感染频率和隐匿性 HCV 感染的临床演变，以验证这一意外发现。
