Chattopadhyay Saket, Das B C, Gupta R K, Kar P
PCR-Hepatitis Laboratory, Department of Medicine, Maulana Azad Medical College, New Delhi, India.
Indian J Med Res. 2005 Jul;122(1):29-33.
BACKGROUND & OBJECTIVE: The recent discovery of a novel parenterally transmitted, unenveloped, single-stranded DNA virus called TT virus (TTV) in chronic hepatitis patients with unclear pathogenesis throughout the world led us to investigate, its presence in chronic hepatitis patients attending a hospital in New Delhi, India, and to evaluate its role in liver disease.
TT virus DNA was investigated in serum samples of 70 patients with various types of chronic hepatitis, and 100 healthy subjects from New Delhi, India by nested PCR using the primers that belonged to UTR (A) region of the genome.
TTV DNA was detected in 6 of 23 patients (26%) with type B chronic hepatitis, 3 of 20 patients (15%) with type C chronic hepatitis, and 12 of 100 subjects (12%) from healthy control group with normal liver function profile tests. None of the 27 non-B, non-C chronic hepatitis patients had TTV DNA positivity. The prevalence of TTV was significantly higher in type-B chronic hepatitis patients as compared to normal subjects (P< 0.05) but comparable to type C chronic hepatitis patients. The clinical course and biochemical profiles of type B, or type C chronic hepatitis patients co-infected with TTV did not differ significantly from those without TTV infection.
INTERPRETATION & CONCLUSION: Interestingly, in chronic hepatitis patients, TTV was always associated with either hepatitis B or C virus indicating a likely parenteral route of transmission. All TTV-positive subjects in healthy control group showed normal clinical and biochemical profiles. Thus, the presence of TTV infection is unlikely to influence the course of chronic hepatitis related to hepatitis B virus (HBV) or hepatitis C virus (HCV) or cause liver diseases in healthy subjects.
最近在世界各地病因不明的慢性肝炎患者中发现了一种新型的经肠道外传播的、无包膜的单链DNA病毒,称为TT病毒(TTV),这促使我们对印度新德里一家医院的慢性肝炎患者中该病毒的存在情况进行调查,并评估其在肝脏疾病中的作用。
采用属于该基因组UTR(A)区域的引物,通过巢式PCR对70例不同类型慢性肝炎患者和100名来自印度新德里的健康受试者的血清样本进行TT病毒DNA检测。
在23例B型慢性肝炎患者中有6例(26%)检测到TTV DNA,20例C型慢性肝炎患者中有3例(15%)检测到,100名肝功能检查正常的健康对照组受试者中有12例(12%)检测到。27例非B、非C型慢性肝炎患者中无一例TTV DNA呈阳性。与正常受试者相比,B型慢性肝炎患者中TTV的流行率显著更高(P<0.05),但与C型慢性肝炎患者相当。合并感染TTV的B型或C型慢性肝炎患者的临床病程和生化指标与未感染TTV的患者相比无显著差异。
有趣的是,在慢性肝炎患者中,TTV总是与乙型或丙型肝炎病毒相关,提示可能存在肠道外传播途径。健康对照组中所有TTV阳性受试者的临床和生化指标均正常。因此,TTV感染的存在不太可能影响与乙型肝炎病毒(HBV)或丙型肝炎病毒(HCV)相关的慢性肝炎病程,也不太可能在健康受试者中引起肝脏疾病。