Poor association of TT virus viremia with hepatocellular carcinoma

AIM: The aim of this study was to clarify the relationship between TT virus (TTV) infection and the development of hepatocellular carcinoma. METHODS: TTV from serum was examined in 224 patients with hepatocellular carcinoma (HCC) and 106 patients with chronic liver disease (CLD) but without HCC who were admitted to our hospital between 1995-1997. As controls, 48 patients without liver disease were also examined. TTV DNA was detected using nested PCR method after extraction of DNA from serum. RESULTS: TTV DNA was detected in 29/224 (13%) of patients with HCC; in 14% (4/28) of HCC patients negative for both hepatitis B virus surface antigen (HBsAg) and anti-hepatitis C virus antibody (anti-HCV), in 9% (2/22) of HCC patients positive for HBsAg, and in 12% (21/170) of HCC patients positive for anti-HCV. The prevalence of TTV DNA in HCC patients (13%) was not significantly higher than in CLD patients (22%). There were no significant differences in age, gender, liver function, tumor biology (size, TNM classification), other viral markers, or amount of alcohol intake between TTV-positive and -negative HCC patients. Only a history of blood transfusion was significantly more frequent in TTV-positive HCC patients than in TTV-negative cases (p= 0.02). Coinfection with TTV did not correlate with the severity of HCV-positive liver disease. There was no significant difference in prognosis between TTV-positive and -negative HCC patients. CONCLUSIONS: TTV does not seem to contribute to the development of HCC from chronic liver disease and is not correlated with severity of liver disease.     

Superinfection with hepatitis C virus in patients with symptomatic chronic hepatitis B.

11/323 patients (3.4%) with symptomatic chronic hepatitis B were positive for antibody to hepatitis C virus (anti-HCV). The positive rate of anti-HCV in patients with serum alanine aminotransferase (ALT) levels greater than 200 U/l (n = 219) did not exceed that of the patients with ALT less than or equal to 200 U/l (n = 104) (2.7% vs. 4.8%). Of the 219 patients who were positive for hepatitis B e antigen (HBeAg) and/or hepatitis B virus-DNA (HBV-DNA), 5 (2.3%) had anti-HCV, while 6/104 patients (5.8%) who were positive for antibody to HBeAg (anti-HBe) had anti-HCV (p greater than 0.1). In contrast to the anti-HCV-negative patients, the patients with anti-HCV had a higher percentage of cirrhosis in their liver histological findings (36.4% vs 5.4%, p less than 0.005). In conclusion, the prevalence of HCV superinfection in symptomatic chronic hepatitis B patients is low and HCV superinfection is not an important factor in acute exacerbation of chronic hepatitis B. However, the superinfection with HCV may exacerbate the existing liver disease and accelerate its progression.     

Studies on hepatitis C virus infection in haemodialysis patients]

To examine the prevalence of hepatitis C virus (HCV) in haemodialysis patients without blood transfusion in Hiroshima Prefecture, antibody to HCV (anti-HCV) was studied by the Ortho ELISA Kit in sera from 393 consecutive haemodialysis patients and in sera from 510 age and sex matched healthy members of the general population (control). An additional confirmatory test was done by a recombinant immunoblot assay. 1) Anti-HCV was detected in 70 of the 393 dialysis patients and 3 of the 510 healthy controls (17.8% vs 0.6%, p less than 0.01). Prevalence of anti-HCV in haemodialysis patients sera was increased by the volume of blood transfusion, and even in dialysis patients who had no blood transfusion, the frequency of anti-HCV positivity (9.2%) was greater than the healthy controls (p less than 0.01). Thus, the major route of HCV transmission in haemodialysis patients without blood transfusion may be via the haemodialysis treatment. 2) The prevalence of anti-HCV increased significantly with the ALT level and abnormal ALT activity of the anti-HCV positive group were significantly greater than that of the negative group. Thus, it is suggested that HCV infection may be an etiologic factor of liver dysfunction in haemodialysis patients.     

Clinical significance of TT virus infection in patients with chronic hepatitis C

OBJECTIVE: The TT virus (TTV) is a novel DNA virus that has recently been identified. The clinical significance of TTV infection in patients with chronic hepatitis C has not been determined. The aim of this study was to determine the prevalence and possible role of TTV in a well characterized population with chronic hepatitis C infection. METHODS: Ninety patients with chronic HCV and known time of HCV acquisition were selected from approximately 250 patients followed at our institution. Characteristics including age, sex, histology, and length of disease were recorded. Direct sequencing of the NS5 region was used for HCV genotyping. TTV DNA detection was based on PCR. RESULTS: TTV infection was present in 24 of 90 (27%) HCV patients. Patients were divided into four groups based on stage of disease; chronic hepatitis (CH, 29 patients), compensated cirrhosis (CC, 17 patients), decompensated cirrhosis (DC, 28 patients), and hepatocellular carcinoma (HCC, 16 patients). TTV was present in 2/29 (7%), 2/17 (12%), 11/28 (39%), and 9/16 (56%) in those with CAH, CC, DC, and HCC respectively. TTV was significantly more prevalent among those with advanced disease (DC and HCC) compared to those with stable disease (CH and CC; p = 0.001). Mean age, sex, and the time from exposure to HCV to development of complications were similar in TTV-positive and -negative patients. TTV infection was more common in patients infected with HCV genotype 1b. Univariate analysis showed that length of HCV infection, HCV genotype 1b, and TTV infection were important in predicting the stage of liver disease in HCV patients. However, after adjusting for length of HCV infection, TTV but not HCV genotype was important in predicting the stage of liver disease. CONCLUSIONS: We conclude that 1) TTV infection is common in patients with chronic HCV; 2) TTV infection is more prevalent among patients with advanced HCV-associated liver disease (DC and HCC) than in those with stable disease (CH and CC); and 3) TTV infection is more common in patients with HCV genotype 1b but is independent from genotype in predicting the stage of HCV-associated liver disease.     

Hepatitis C virus infection in patients with leukemia

We have studied 30 patients with acute leukemia by the second-generation assay for antibodies to hepatitis C virus (HCV) to determine the incidence of HCV infection and the impact of anti-HCV positivity on liver disease. After a complete remission, 21/30 (70%) patients were anti-HCV-positive. During chemotherapy the anti-HCV-positive patients had more severe liver disease than the anti-HCV-negative patients, and they had a higher incidence of chronic hepatitis (13/21; 62% vs. 1/9; 11%, P < 0.01). During subsequent follow-up, 15/30 (50%) patients relapsed and 15/30 (50%) patients completed the chemotherapy protocols. After a relapse 12/15 (80%) patients were anti-HCV-positive and they had more severe liver disease than the anti-HCV-negative patients. Among the patients who completed chemotherapy (n = 15), biochemical evidence of chronic hepatitis was found in 9/9 (100%) anti-HCV-positive, and 2/6 (33%) anti-HCV-negative cases during off-therapy follow-up after therapy-withdrawal (P < 0.05). These results indicate that HCV plays an important role in the etiology of chronic hepatitis which could worsen the final prognosis of successfully treated patients with leukemia. © 1994 Wiley-Liss, Inc.     

A survey of current liver biopsy practice patterns

GOALS: To study transfusion-transmitted virus (TTV) infection in 75 patients on hemodialysis and examine its relationship with age, sex, duration of dialysis, history of transfusion, and chronic elevation of alanine aminotransferase (ALT) levels. STUDY: Serum TTV was analyzed by polymerase chain reaction (PCR), TTV genotypes by restriction fragment length polymorphism, and hepatitis C virus (HCV) RNA by PCR. RESULTS: Transfusion-transmitted virus was detected in 32 patients (42.7%). Transfusion-transmitted virus genotypes were as follows: G1 in 16 patients; G2, 3; G3, 1; G4, 2; G2-G5, 6; and unclassified, 4. Mean duration of dialysis was 37 +/- 32 months for TTV-positive patients and 43 +/- 37 months for TTV-negative patients (not significant). Twenty-seven (84%) TTV-positive patients and 27 (63%) TTV-negative patients had a history of transfusions ( p = 0.04). Chronic ALT elevation was observed in 9 patients; 5 of them were TTV-positive (16%) and 4 were TTV-negative (9%) (not significant). Four (40%) HCV RNA-positive patients and 5 (8%) HCV RNA-negative patients had chronic ALT elevation ( p = 0.003). Three TTV-positive patients with chronic ALT elevation were also infected with HCV. The two patients with isolated TTV infection did not have another clinical feature to explain their ALT elevation. CONCLUSIONS: Transfusion-transmitted virus had a high prevalence in the patients on hemodialysis; genotype G1 accounts for half of the cases. Transfusion-transmitted virus infection depends on the transfusional antecedent but not on the duration of dialysis. Chronic ALT elevation is significantly associated with HCV infection but not TTV infection. However, TTV could be a causative agent of chronic ALT elevation in some patients.     

TT virus infection in hemodialysis patients

OBJECTIVE: Recently, TT virus (TTV), associated with posttransfusion hepatitis, was discovered. Prevalence of TTV infection in maintenance hemodialysis (HD) units and its pathogenicity to liver was investigated. METHODS: A total of 115 patients on HD were assessed for presence of serum TTV. DNA was purified from sera, and nested polymerase chain reaction was done for the detection of TTV DNA. RESULTS: TTV was detected in 59 patients on HD (51.3%), as compared with healthy blood donors (15 of 91 [16.5%], p < 0.0001). Serum HCV RNA and HBs antigen were positive in 16 and three patients, respectively. The prevalence rate of TTV was already 58.3% in the patients on HD for only 1 yr, and did not change according to the duration of HD until 15 yr on HD. TTV was positive in 51.2% (43 of 84) of the patients with history of blood transfusion, and in 51.6% (16 of 31) of those without it. In HCV-negative patients, alanine aminotransferase (ALT) levels of TTV-positive patients were similar to those of TTV-negative patients. Contrarily, in HCV-positive patients, ALT levels were more frequently > or =15 IU/L in TTV-positive patients (14 of 18) than in TTV-negative patients (five of 15) (p < 0.05). CONCLUSIONS: TTV infection is remarkably prevalent in patients on HD and in healthy blood donors. It is suggested that TTV generally does not cause liver disease by itself, but there remains the possibility that TTV may aggravate liver disease caused by HCV.     

TT virus infection during chronic hepatitis C

OBJECTIVE: The pathogenic role of TT virus (TTV) is not well known, especially during chronic hepatitis C virus (HCV) infection. We retrospectively investigated the presence of TTV DNA in the plasma of patients with chronic HCV infection and compared the characteristics of TTV-DNA-positive and -negative groups. METHODS: Between November 1996 and November 1998, 234 patients were included. Inclusion criteria were persistently elevated serum alanine aminotransferase (ALT) levels, anti-HCV and HCV-RNA positivity, and seronegativity for hepatitis B virus and human immunodeficiency virus markers. TTV DNA was amplified in nested polymerase chain reaction with TTV-specific primers, and products were analyzed by agarose-gel electrophoresis. Data were analyzed using the chi2, Fisher's exact test, or Mann-Whitney test, as appropriate. RESULTS: TTV DNA was detected in 19 (8.1%; 95% confidence interval: 4.6-11.6%) patients. TTV-DNA-positive and TTV-DNA-negative patients did not differ statistically for age, gender ratio, source of HCV infection, HCV disease duration, biological parameters, histological grade, HCV-RNA load, or HCV genotype. Although nonsignificant (p = 0.21), there was a trend for a higher prevalence of TTV DNA in patients with an unknown cause of HCV infection (4/22, 18.2%) than in intravenous drug users (4/84; 4.8%), in those exposed to potential risk factors (4/49; 8.2%), or in those having received blood transfusion (7/79; 8.9%). CONCLUSIONS: Because the rates of HCV replication and the severity of liver lesions in TTV-DNA-negative and -positive patients were similar, the hepatic pathogenicity of TTV in chronic hepatitis C patients is questionable.     

Hepatitis C virus antibodies, viral RNA and genotypes in sera from patients on maintenance haemodialysis

SUMMARY. Patients on maintenance haemodialysis in four dialysis centres were tested for markers of hepatitis C virus (HCV) infection. Antibody to HCV (anti-HCV) was detected by the second-generation enzyme immunoassay in 142 (26%) of the 543 patients and HCV RNA in 117 (22%) of whom four were without detectable anti-HCV in serum. Seventy-seven (66%) were infected with HCV of genotype II/1b, 31 (27%) with genotype III/2a and eight (7%) with genotype IV/2b. in a distribution similar to that in blood donors who carried HCV asymptomatically. Haemodialysis patients had high HCV RNA titres comparable to those of patients with chronic hepatitis C. HCV RNA was detected in 96 (26%) of the 365 patients with a history of transfusion more frequently than in 21 (12%) of the 178 without previous transfusion ( P <0.001). In transfused patients, frequencies of anti-HCV and HCV RNA increased in parallel with the duration of haemodialysis. The frequency of anti-HCV in non-transfused patients, however, did not change appreciably with the duration of haemodialysis up to 22 years. The patients with anti-HCV had a higher frequency of HCV RNA in serum than symptom-free blood donors with anti-HCV (113/142 or 80% vs 109/166 or 66% P <0.01) and the patients with HCV RNA had a lower frequency of elevated aminotransferase levels than blood donors with HCV RNA (5/113 or 4% vs 27/109 or 25%, P <0.00l). These results indicate that transfusion is a significant cause of HCV infection in patients on maintenance haemodialysis, and that these patients are prone to establish the HCV carrier state after infection.     

Clinical implications of TT virus superinfection in patients with chronic hepatitis C

OBJECTIVE: TT virus (TTV) has been identified as a candidate agent of non-A-E hepatitis virus. We investigated superinfection of TTV in patients with chronic hepatitis C and studied the susceptibility to interferon (IFN) treatment and its association with liver disease caused by hepatitis C virus (HCV). METHODS: TTV DNA was examined using the seminested polymerase chain reaction (PCR), and its virus level was measured by the real-time fluorometric PCR. RESULTS: TTV DNA was detected in 20 of 102 (19.6%) patients examined. There was no significant difference in the alanine aminotransferase (ALT) level between patients with or without TTV DNA. Quantitative analysis of HCV RNA and TTV DNA revealed no correlation between virus levels in HCV/TTV-coinfected patients. Both TTV and HCV were sensitive to IFN therapy. Complete response to IFN with a sustained loss of viremia for 24 wk after completion of IFN treatment was found in 11 of 20 (55%) patients with respect to TTV DNA and in five of 20 (25%) patients with respect to HCV RNA. The mean pretreatment HCV RNA level was significantly lower in the complete-response cases than in the no-response cases, but there was no significant difference in the pretreatment TTV DNA levels between them. ALT normalization resulting from IFN therapy was not attributable to the eradication of TTV DNA but was attributable to that of HCV RNA. Superinfection by TTV did not influence the effect of IFN against HCV. No specific TTV genotype correlating with IFN sensitivity was found. CONCLUSIONS: These results suggest that TTV infection stands independent of HCV infection, with no influence on liver injury as a result of HCV infection.     

Clinical impact of genotype 1 TT virus infection in patients with chronic hepatitis C and response of TT virus to alpha-interferon

BACKGROUND: The relationship between genotype 1 TT virus (TTV) infection and the status of chronic hepatitis C was studied. METHODS: A total of 52 patients with chronic hepatitis C who were treated with interferon (IFN)-alpha were enrolled in the present study. Of those, 12 were infected with genotype 1 TTV and 40 were uninfected. RESULTS: Clinical backgrounds, including mean age, sex, blood transfusion history, serum alanine aminotransferase (ALT) level, and the results of liver biopsy did not differ between patients with and without genotype 1 TTV infection. The distribution of hepatitis C virus (HCV) genotypes did not differ between the two groups of patients, but TTV-infected patients tended to have a lower serum HCV-RNA level than uninfected patients (median (range) 26.0 (< 1-460) vs 135 (1.2-740) kilo copies/mL, respectively; P = 0.065). Patients with a sustained response of HCV to IFN-alpha were significantly more common in TTV-infected than -uninfected patients (58 vs 23%, respectively; P = 0.018). Multivariate logistic regression analysis revealed that patients with a sustained response of HCV correlated significantly with the serum HCV-RNA level (P = 0.006), but not with the presence or absence of genotype 1 TTV infection (P = 0.161). Serum TTV-DNA decreased with IFN-alpha therapy in all 12 patients and remained negative in six patients even after treatment. There was no correlation between patients with a sustained response of HCV and the same of TTV. Serum ALT levels correlated with changes in the status of HCV viremia, but not with changes in the status of TTV viremia. CONCLUSIONS: An opposing relationship between HCV and TTV proliferation was suggested, but coinfection with genotype 1 TTV did not affect the status of chronic hepatitis C.     

TT viral infection through blood transfusion: retrospective investigation on patients in a prospective study of post-transfusion hepatitis

AIM To investigate the role of blood transfusion in TT viral infection (TTV).METHODS We retrospectively studied serum samples from 192 transfusion recipients who underwent cardiovascular surgery and blood transfusion between July 1991 and June 1992. All patients had a follow-up every other week for at least 6 months after transfusion. Eighty recipients recipents blood before screening donors for hepatitis C antibody (anti-HCV), and 112 recipients reveiver screened blood.Recipients with alanine aminotransferase level ＞ 2.5 times the upper normal limit were tested for serological markers for viral hepatitis A, B,C, G, Epstein-Barr virus and cytomegalovirus.TTV infection was defined by the positivity for serum TTV DNA using the polymerase chain reaction method. RESULTS Eleven and three patients, who reveiver anti-HCV unscreened and screened blood, respectively, had serum ALT levels ＞90 IU/L. Five patients (HCV and TTV: 1; HCV,HGV, and TTV: 1; TTV: 2; and CMV and TTV: 1 )were positive for TTV DNA, and four of them had sero-conversion of TTV DNA. CONCLUSION TTV can be transmitted via blood transfusion. Two recipients infected by TTV alone may be associated with the hepatitis.However, whether TTV was the causal agent remains unsettled, and further studies are necessary to define the role of TTV infection in chronic hepatitis.     

Clinical characteristics and distribution of genotypes of TT virus infection in a hepatitis C virus-hyperendemic township of a hepatitis B virus-endemic country (Taiwan)

BACKGROUND: The prevalence of TT virus (TTV) viremia, without definite clinical significance, has been reported to be higher among chronic hepatitis C patients. The status and clinical characteristics of TT virus (TTV) infection and distribution of TTV genotypes in a hepatitis C virus (HCV) hyperendemic township (Masago community) in a hepatitis B virus (HBV) endemic country (Taiwan) were investigated. METHODS: Sera from 100 Masago residents were tested for alanine aminotransferase (ALT) and markers of HBV, HCV and GB virus C/hepatitis G virus (GBV-C/HGV) and TTV-DNA. Sera of 250 blood donors as a control group were tested for TTV-DNA. Sera of Masago residents and blood donors with positive TTV-DNA were directly sequenced, and phylogenetic analyses were performed subsequently. RESULTS: The prevalences of TTV viremia in different age groups among individuals from Masago were significantly higher than that among blood donors. In regard to the subtypes of TTV, 23, seven, two, eight, one, six and one isolate were related to the genotypes 1a, 1b, 2a, 2b, 3, 4 and 5, respectively, from Masago and 21, 14, one, nine and three isolates were related to the genotypes 1a, 1b, 2a, 2b, and 4, respectively, from donors. No clinical or virological factor was associated with TTV viremia or TTV genotypes. CONCLUSIONS: TT Virus prevalence was higher among HCV hyperendemic township residents than blood donors with similar genotype distributions (genotype 1 was the most prevalent) in Taiwan. Neither TTV viremia nor a particular genotype was associated with HBV, HCV or GBV-C/HGV infection and abnormal ALT levels.     

Clinical significance of TT virus in chronic hepatitis C

BACKGROUND AND AIMS: Much is still unknown about the clinical significance of TT virus (TTV), which has been reported as a candidate for non A-G hepatitis virus. The aim of this study was to clarify the clinical significance of TTV in patients coinfected with TTV and hepatitis C virus (HCV). METHODS: The 95 subjects studied had chronic hepatitis C (CHC), and underwent interferon (IFN) therapy. TT Virus DNA was detected by using polymerase chain reaction. The nucleotide sequences were determined by using a dideoxy chain termination method. A phylogenetic tree was drawn up by using the neighbor-joining method. RESULTS: TT Virus DNA was detected in 37.9% of patients with the use of an open reading frame 1 (ORF1) primer, and in 88.4% of patients by using a 5' untranslated region (5' UTR) primer. Using both sets of primers, no differences were found between TTV-DNA-positive and -negative subjects with CHC in the clinical findings. Serum TTV DNA was eradicated in 30.6% of patients with the ORF1 primer, and in 19.1% of patients with the 5' UTR primer at 6 months after the cessation of IFN therapy. The levels of TTV DNA before IFN therapy were significantly lower in the viral eradication group than in non-eradication group. The changes in alanine aminotransferase (ALT) concentrations were significantly correlated with changes in HCV-RNA in CHC patients with TTV. Moreover, there was no correlation between the changes in TTV DNA and the course of ALT. CONCLUSION: Hepatocellular injury in patients with chronic hepatitis who are coinfected with HCV and TTV appears to primarily be caused by HCV and is less attributable to TTV.     

Risk of hepatitis C virus infection among household contacts of Saudi patients with chronic liver disease

SUMMARY. To evaluate the intrafamilial transmission of heptitis C virus and related risk factors among the Saudi population, two groups were investigated: 120 index patients with chronic liver disease and their 127 family contacts, and 220 blood donors who were anti-HCV-positive but with no chronic liver disease and their 91 family contacts. After a questionnaire on the risk factors for parenteral exposure, blood samples were obtained and tested for liver biochemistry and antibody to HCV (anti-HCV) by a third-generation enzyme immunoassay (UBI HCV HA4.0). Only two spouses of 20 index patients were anti-HCV-positive while the remaining 125 family contacts were anti-HCV-negative. None of the 91 family contacts of the 20 anti-HCV-positive blood donors was anti-HCV-positive. The two spouses were wives of index patients but had a history of blood transfusion on at least two different occasions. Our results clearly indicate the intrafamilial transmission of HCV is not the route of transmission of HCV among Saudis and our results argue against sexual transmission of hepatitis C virus despite a relatively long duration of marriage.     

TT virus is shown in the liver by in situ hybridization with a PCR-generated probe from the serum TTV-DNA

BACKGROUND AND AIM: It has been a conflicting issue whether TT virus (TTV), a newly isolated DNA virus from a patient with liver injury of unknown cause, is a causative agent of acute and/or chronic hepatitis. TT Virus DNA titers were shown to be 10-100-fold greater in liver tissue than in serum, whereas the majority of TTV-positive cases had no biochemical or histological evidence of significant liver damage. We therefore attempted in situ hybridization to investigate whether TTV is hepatotropic. METHODS: Because of the marked divergence in TTV genome types, a template for TTV-DNA (coding region for N22 clone) was amplified and labeled with digoxigenin-dUTP by using hemi-nested PCR from the serum, then DNA probes were applied to the liver sections of the same case. After hybridization, the probes were visualized immunohistochemically. Besides TTV-DNA-negative cases, competitive inhibition experiments with unlabeled probes were performed to confirm the specificity. RESULTS: There were no positive signals in the negative controls, and the intensity of positive signals was markedly diminished in the competitive inhibition experiments. No cross-hybridization with different genotype probes also confirms the specificity. Under the optimal conditions, the positive signals were located in the cytoplasm of the hepatocytes in eight of nine TTV-DNA-positive cases. The signals were not seen in non-parenchymal cells of the liver. CONCLUSION: TT Virus is proved to be hepatotropic by in situ hybridization.     

长春地区TT病毒的基因分型及其临床意义

为调查各种急、慢性肝炎中TT病毒的感染状况及临床意义,并检测TTV基因的分型。利用半套式PCR（semi-nested PCR）方法检测了TTV-DNA。利用邻近丁（neighbor-joining）法画出系统树。TTV-DNA的阳性率在非甲非乙非丙型急性肝炎中为42.3%,在非乙非丙型慢性肝炎中为45.5%。基因型可分为1a、1b、2a、2b等型。TTV-DNA在非甲非乙非丙型急性非乙非丙型慢性肝炎中的感染率最高;在TT病毒与乙型、丙型肝炎病毒混合感染的慢性肝炎中,TT病毒干涉乙型及丙型肝炎病毒造成的肝细胞损伤的可能性很小。     

A prospective study of transfusion-transmitted virus transmission by blood transfusion

Recently, a new single-stranded DNA virus (TT virus, TTV) has been isolated and related to post-transfusion hepatitis. The aim of this study was to investigate the prevalence of TTV in blood donors and blood recipients, and the incidence of TTV transmission by blood transfusion. TTV DNA and serum markers of hepatitis B virus (HBV) and hepatitis C virus (HCV), were examined in 130 blood recipients, and the presence of TTV was studied in their 340 corresponding blood donors. The prevalence of TTV infection was 10.6% (36/340) in donors and 8.5% (11/130) in blood recipients, before transfusion. Eighteen subjects (15.1%) were found to be TTV positive, after transfusion, in the 119 blood recipients without TTV before transfusion; at least one of the corresponding donors was TTV positive. There were 46 subjects with post-transfusion hepatitis virus infection, 45 with HCV infection (including seven co-infected with TTV) and two with HBV infection (including one co-infected with HCV and one co-infected with TTV). The recipient with TTV and HBV co-infection and three of the seven patients with TTV and HCV infection had alanine aminotransferase (ALT) levels higher than 90Ul^–1, but only two of the 10 isolated TTV infections had a mild ALT elevation. These results show that prevalence of TTV was high in blood donors and hospitalized patients, and isolated TTV infection is not related to significant ALT elevation.     

Hepatitis G virus infection in haemodialysis patients and its relationship with hepatitis C virus RNA positivity

A novel RNA virus designated hepatitis G virus (HGV) was identified recently in patients with acute and chronic liver disease. Since HGV may be transmitted parenterally, chronic haemodialysis (HD) patients are at increased risk for acquiring this infection. 110 chronic HD patients were studied (56 HCV-RNA and anti-HCV-positive, and 54 HCV-RNA and anti-HCV-negative). HGV-RNA and HCV-RNA were studied by RT-PCR. HCV genotype determination was applied to all 56 HCV-RNA-positive patients. 28 of 110 (25%) patients were found be HGV-RNA-positive. HCV-RNA-positive patients had higher rate of HGV-RNA positivity compared with HCV-RNA-negative patients. The HCV genotypes of HGV-RNA-positive patients were mostly 4 (48%) and 1b (33%). HGV was not linked with HBsAg positivity. While there was a significant correlation between HCV-RNA positivity and the number of blood transfusions and duration of HD, we did not observe this relationship in HGV-RNA-positive patients. These results indicate that the prevalence of HGV is high in HD patients and that HGV-RNA positivity is higher in HCV-RNA-positive patients.     

TTV阳性肝病患者的临床与病理学特征初步观察

目的 观察ＴＴＶ阳性肝病患者的临床和病理特征。方法 用巢式ＰＣＲ法检测ＴＴＶ－ＤＮＡ,同时观察血清生化指标,肝组织活检观察其病理变化。结果 ＴＴＶ感染者的血清学模式以重叠ＨＢＶ、ＨＣＶ、ＨＡＶ、ＨＥＶ、ＨＧＶ二重感染为主占５７．９％（２２／３８）,以乏力、纳差、腹胀为临床特征,ＴＢｉＬ、ＡＬＴ变化不明显,ＴＴＶ单独感染者为４２．１％（１６／３８）,急性发病者临床特征多与“急性黄疸性肝炎”相似,病理改变与各型病毒性肝炎的病理变化基本相似,但主要以肝门脉区炎症,小叶间胆管损伤,灶状坏死为多见。结论 ＴＴＶ可与各型已知肝炎病毒重叠感染也可单独感染。