Clinical significance of TT virus infection in patients with chronic liver disease and volunteer blood donors in Egypt

Clinical significance of TT virus (TTV) infection was investigated in Egyptian patients with chronic liver disease and volunteer blood donors by a cross sectional analysis. TTV DNA in serum was assessed by a semi-nested polymerase chain reaction. The prevalence of TTV DNA did not differ among patients with chronic hepatitis B (11/24, 46%), chronic hepatitis C (22/72, 31%), or schistosomal liver disease (14/39, 36%). No difference in prevalence was found between blood donors (32/109, 29%) and each of the patient groups. Clinical background including mean age, sex distribution, history of blood transfusion, and mean level of alanine aminotransferase did not differ between TTV DNA-positive and -negative individuals in any of the study groups. Ultrasonographic evidence of liver cirrhosis was similar between TTV-positive and -negative patients in each of the chronic liver disease groups. TTV infection was not associated with hepatitis B or C virus infection in blood donors. The only significant difference observed was the lower concentration of serum HCV RNA in TTV DNA positive compared with negative patients with chronic hepatitis C (3.0 +/- 1.4 vs. 4.0 +/- 0.9 log copies/ml, P <. 001). In conclusion, TTV infection was not associated with either past history of blood exposure or infection with bloodborne hepatitis viruses in Egypt. No clinical significance of TTV was found in the present study. However, a reciprocal interaction was suggested between TTV and HCV replication.     

Occurrence of a novel DNA virus (TTV) infection in patients with liver diseases and its frequency in blood donors.

A novel DNA virus (TTV) was identified recently in Japanese patients with posttransfusion hepatitis non-A-E and has been implicated as a cause of acute and chronic liver diseases of unknown etiology in some patients. The frequency of TTV infections was investigated in 284 blood donors, 105 patients with different liver disorders before and after liver transplantation (OLT), as well as in 64 patients with chronic hepatitis C who received antiviral therapy. TTV infections were found more frequently by nested-PCR in patients with liver disorders (15%) as compared to blood donors (7%). TTV occurred independently of the aetiology of the liver disease (e.g., cryptogenic cirrhosis [12.5%], alcoholic cirrhosis [16%], fulminant hepatic failure non-A-E [35%], and chronic hepatitis C [12.5%]; p=n.s.). After OLT, a high rate of TTV de novo infections (44%) was observed. However, TTV viremia after OLT (in 56 out of the 105 patients) was not associated with graft hepatitis. Analysis of patients with chronic hepatitis C coinfected with TTV who have been treated with interferon alpha alone or in combination with ribavirin revealed that TTV is an interferon-sensitive virus. Phylogenetic analysis of TTV sequences suggest that at least four different genotypes and several subtypes exist in Germany. In conclusion, the high prevalence of TTV infections observed in patients with parenteral risk factors is an argument in favour of transmission of the virus via blood and blood products. A relevant hepatitis-inducing capacity of TTV, however, seems unlikely, considering the observation that in the majority of patients, TTV infection after OLT was not accompanied by graft hepatitis.     

分子杂交法研究肝炎病人血清和肝组织中输血传播病毒

目的 对各型肝炎病人血清和肝组织中输血传播病毒（TTV）核酸检测分析,探讨病毒的致病性。方法 以地高辛为标记物制备TTV DNA探针,斑点杂交法、原位杂交法分别检测血清中及肝组织中TTV DNA。结果 检测103例血清,TTV总阳性率为25．24％（26／103）;甲－戊型肝炎组检出率21．81％（12／55）、非甲－非庚型患者检出率47．37％（9／19）,显著高于正常对照组15％（3／20）。临床可见TTV的单独感染和重叠感染;出现急性、慢性甚至重度肝损伤。12 肝组织可见TTV阳性,阳性颗粒主要见于肝细胞核内。结论 从血清和肝组织证实了TTV的存在,提示这种病毒可能是导致肝脏炎症的一种新病原。     

GB virus C/hepatitis G virus and TT virus infections among high risk renal transplant recipients in India.

BACKGROUND: GB virus C/hepatitis G virus (GBV-C/HGV) and TT virus (TTV) have been widely reported in patients with high parenteral risk such as haemodialysis and renal transplant recipients. The occurrence of these agents in association with hepatitis B virus (HBV) and hepatitis C virus (HCV), in Indian renal transplant recipients, is yet unreported. STUDY DESIGN: Molecular and serological markers of GBV-C/HGV and TTV were examined in addition to those for HBV, HCV and hepatitis D virus (HDV) in a selected group of seventy renal transplant recipients. HGV RNA detection was achieved using primers specific for the 5'NCR and NS5a regions of the genome. Anti-GBV-C/HGV antibody was detected using the mu plate anti-HG env kit (Roche, Germany). TTV DNA PCR was performed using primers specific for the coding region (method A) of the genome. In 50% of patients, TTV DNA was also tested for using primers specific for the non-coding region (method B). Host related factors such as age, alanine aminotransferase (ALT) levels, number of transfusions, haemodialysis sessions, and months following transplantation were also studied. RESULTS: Exposure rates to GBV-C/HGV, TTV (method A), HBV, HCV and HDV were 58.6, 32.9, 52.9, 54.3 and 2.9%, respectively. 'Active' infection as measured by viraemia and/or virus-specific antigenaemia for GBV-C/HGV, TTV, HBV and HCV was 52.9, 32.9, 15.7 and 52.9%, respectively. The majority of GBV-C/HGV and TTV infections were seen as co-infections with other hepatitis viruses. Single infection with GBV-C/HGV and TTV was seen in ten (14.2%) and eight (11.4%) patients, and was not associated with ALT elevation when compared to uninfected blood donors. Using univariate analysis, GBV-C/HGV RNA was significantly associated with > or =20 haemodialysis sessions. TTV DNA occurrence was not associated with any risk factors. CONCLUSIONS: There is a high occurrence of GBV-C/HGV and TTV in this select group of renal transplant recipients in India. These viruses mostly occurred in the context of co-infections with other hepatitis viruses. Long term effects of multiple hepatotropic viral infections need to be carefully documented in such transplant populations.     

原位杂交法检测非甲～庚型肝炎患者肝组织中TT病毒DNA

目的 证实在非甲－庚型病毒性肝炎患者肝组织中TT病毒（transfusion-transmitted virus,TTV)的存在。方法 采用地高辛素标记TTV DNA探针以原位杂交技术对51例血清学病毒标记非甲－戊型、免疫组化检测肝组织中HBsAg、HCV NS3Ag及HGV N55Aag阴性的病毒性肝炎患者石蜡包埋肝组织进行了检测。结果 各型病毒性肝炎肝组织中TTV基因的总检出率为27．5％,其中急性轻型肝炎的检出率为30．8％（4 ／13）,急性重型肝炎为1／8,亚急性重型肝炎为3／7,慢性肝炎为2／6,活动性肝硬化为2／9,慢性重肝肝炎为1／4,原发性肝癌为1／4。TTV DNA表达于肝细胞核或胞质内,以核型多见。在急性肝炎,TTV阳性细胞弥漫分布于肝小叶内,慢性肝炎于汇管区附近较为密集,而在肝硬化病例,阳性细胞在假小叶内多呈片族状不规则分布。结论 在不明原因病毒性肝炎患者血清及肝组织中TTV DNA的检出表明TTV为一种新型的肝炎病毒,TTV为一种嗜肝性病毒。     

TTV infection and its relation to serum transaminases in apparently healthy blood donors and in patients with clotting disorders who have been investigated previously for hepatitis C virus and GBV-C/HGV infection in Belgium

A novel DNA virus, TT virus (TTV), has been proposed as a possible etiologic agent for non A-E hepatitis. The aim of the present study was to determine the prevalence of TTV infection using PCR in healthy blood donors and in patients with clotting disorders who have been investigated previously for GBV-C/HGV and HCV infection in Belgium. In this study, PCR using primers proposed by Takahashi et al. [(1998) Hepatology Research 12:233-239] proved far more sensitive than those used by Okamoto et al. [(1998) Journal of Medical Virology 56:128-132]. The sequence of the PCR products showed 87% identity to the published sequence. TTV was present in 29.7% of healthy blood donors, a figure intermediate between the low rate of infection observed in Scotland and the high rates in the Far East. TTV was detected in 46.5% of 127 patients studied with clotting disorders as compared to 79.5% for HCV and 11.8% for GBV-C/HGV infection. However, there was no impact on the level of serum transaminases. Treatment with interferon for HCV infection co-infected with TTV suppressed temporarily serum TTV DNA. Therefore, it was concluded that TTV DNA is detected frequently in serum of healthy blood donors in Belgium and more often in patients with clotting disorders. TTV does not cause liver disease or contribute to the severity of liver disease.     

High prevalence and phylogenetic analysis of TT-virus infection in Mongolia

A novel DNA virus, TT-virus (TTV), was isolated from a post-transfusion hepatitis patient in Japan. The prevalence of TTV infection was investigated among patients with chronic liver disease and normal alanine aminotransferase (ALT) volunteers as controls in Mongolia. Polymerase chain reaction (PCR) was employed to detect TTV DNA using specific primers derived from open reading frame 1 (ORF1) of the TTV genome. Nucleotide sequences of samples positive for TTV DNA were determined. The sequences were analyzed by a molecular evolutionary method. Fifty (60.2%) hepatitis patients and 12 (42.9%) volunteers were positive for TTV DNA. The serum ALT levels did not differ significantly between patients with single TTV infection and without TTV, HBV and HCV infection. Similarly, the serum ALT levels did not differ significantly between controls with and without TTV infection. Dual infection of TTV with either HBV or HCV did not affect the ALT levels of hepatitis patients. The molecular evolutionary tree showed that TTV was a heterogeneous virus and all strains could be divided into three genotypes in Mongolia. A new genotype was identified that was distinct from those previously reported.     

TT virus infection in patients with chronic hepatitis B or C: influence on clinical, histological and virological features

Concomitant infection with TT virus and hepatitis B virus (HBV) or hepatitis C virus (HCV) is common. However, the effect of TTV infection on chronic hepatitis B or C is unknown. The prevalence of TTV infection, the effect of TTV infection on the clinical, histological and virological features of patients with chronic hepatitis B or C, and the influence of TTV infection on the HCV response to interferon alfa therapy were studied. A total of 100 asymptomatic hepatitis B surface antigen carriers, 220 patients with HBV-related chronic liver diseases, and 110 patients with chronic hepatitis C treated with interferon alfa (3 million units subcutaneously three times a week for 24 weeks) were enrolled. Serum HCV RNA and serum TTV DNA were detected by the polymerase chain reaction (PCR). Serum HBV DNA and serum HCV RNA level were quantified by branched DNA assays. Infection with TTV was detected in 21.5% of HBV carriers and 37% of HCV carriers. TTV infection had little effect on the clinicopathological course of chronic HBV infection. In chronic hepatitis C, clinical features, histological severity, serum HCV RNA levels, and the response to interferon alfa therapy did not differ between those with and without TTV infection. The loss of serum TTV DNA did not correlate with the biochemical response as did in the loss of serum HCV RNA. In conclusion, TTV infection is found frequently in patients with chronic hepatitis B or C in Taiwan; however, coinfection with TTV does not affect the clinicopathological course of chronic hepatitis B or C and the response to interferon alfa therapy.     

High prevalence of TT virus (TTV) infection in patients on maintenance hemodialysis: frequent mixed infections with different genotypes and lack of evidence of associated liver disease.

Recently, a novel DNA virus, TT virus (TTV), was identified in patients with post-transfusion non-A-G hepatitis. We analyzed the prevalence and clinical implications of TTV infection in a cohort of 96 Spanish patients on long-term hemodialysis. TTV DNA was detected by nested PCR in 51 (53%) of 96 patients, a prevalence significantly higher than that found in healthy blood donors. Persistent liver test abnormalities were found in only 2 (7.7%) of 26 patients infected with TTV alone, compared with 12 (75%) of 16 patients infected with hepatitis C or hepatitis B virus, or both (P < 0.01). Mixed infections with multiple strains of TTV, including different major genotypes, were common in patients on hemodialysis. These patients had received a significantly greater number of blood units (22.7 +/- 20) compared with patients apparently infected with a single strain of TTV (8.9 +/- 11) (P = 0.01). Phylogenetic analyses of TTV from infected patients identified strains of genotypes 1, 2, 3, and 4. In summary, TTV infection was common in patients on hemodialysis but was not associated with liver disease     

Infection with an unenveloped DNA Virus (TTV) associated with posttransfusion non-A to G hepatitis in hepatitis patients and healthy blood donors in Thailand

An unenveloped single-stranded DNA virus (TTV) has been reported in association with posttransfusion and acute and chronic hepatitis of unknown etiology. DNA of TTV was tested for by polymerase chain reaction with heminested primers in 127 patients with chronic liver disease and 105 healthy blood donors in Thailand. TTV DNA was detected in 23 (59%) of the 39 patients without hepatitis B surface antigen or RNA of hepatitis C virus, at a frequency significantly higher than the detection in 21 (36%) of the 59 patients with HBsAg (P < 0.05) or in 38 (36%) of the 105 blood donors (P < 0.05). Among patients with chronic liver disease, TTV DNA occurred in those with liver cirrhosis and hepatocellular carcinoma more frequently than in those with chronic hepatitis (35 of 65 or 54% vs. 20 of 62 or 32%, P < 0.05). There were no differences in age, sex, or markers of infection with hepatitis B, C and GBV-C/HGV viruses, indicating a mode of transmission of TTV different from those of the other hepatitis viruses. Phylogenetic analysis indicated three different genotypes of TTV with six distinct subtypes in Thailand. Based on these results, TTV would have a role in the development of chronic liver disease of unknown etiology in Thailand. J. Med. Virol. 56:234–238, 1998. © 1998 Wiley-Liss, Inc.     

TT virus infection in patients with chronic liver disease of unknown etiology

The role of a novel virus, designated as TT virus (TTV), as a cause of chronic liver disease has not been well defined. We investigated the prevalence of TTV among 69 patients with chronic liver disease of unknown etiology and 50 volunteer blood donors with normal transaminase levels. TTV DNA was amplified by polymerase chain reaction (PCR) by using two different sets of primers: one based on the sequence of the original N22 clone within the open reading frame 1 (set A) and the other derived from the untranslated region (set B). The prevalence of TTV detected by PCR primers set A only, set B only, and in total (by either set A or B) was 11 (31%), 31 (86%), and 31 (86%) of 36 patients with chronic hepatitis; 2 (40%), 4 (80%), and 4 (80%) of 5 with cirrhosis; 11 (39%), 17 (61%), and 22 (79%) of 28 with hepatocellular carcinoma; and 9 (18%), 39 (78%), and 40 (80%) of 50 volunteer blood donors, respectively. Of the interpretable 25 PCR products amplified with primers set A, 9 were classified as genotype 1a, 10 as genotype 1b, 4 as genotype 2, 1 as genotype 3, and 1 as genotype 4. Molecular evolutionary analysis did not suggest any particular strains of TTV that might be associated with chronic liver disease. The nucleotide sequences of the untranslated region on which PCR primers set B were designed were highly conserved, and the interpretable 22 PCR products amplified with primers set B were not clearly divisible into distinct genotypes. Our findings provided no evidence that TTV is a causative agent of chronic liver disease.     

Prevalence of TT Virus and GBV-C Infections among Patients with Liver Diseases and the General Population in Shanghai,China

To determine the prevalence of TT virus (TTV) and GB virus C/hepatitis G virus (GBV-C) infections among patients with liver disease and the general population in Shanghai, China, we studied 90 patients with liver diseases (acute hepatitis, 28; chronic hepatitis, 27; liver cirrhosis, 20; hepatocellular carcinoma, 15) and 90 age, sex matched healthy blood donors as controls. There were no significant differences in the clinical and demographic characteristics between the two groups, except for liver function test values. There was a statistical difference between the patient group and the control group with regard to the prevalence of TTV DNA (23.5% in patient group, 11.1% in control group, P<0.05), although no differences in clinical features could be found between TTV DNA-positive and negative subjects. Also, no differences in TTV DNA prevalence among various categories of liver diseases were noted (P = NS). The prevalence of HBsAg was significantly different between the patient group (36.7%) and the control group (3.3%) (P<0.01), whereas the prevalence of anti-HCV and GBV-C RNA were not significantly different between the two groups. The nucleotide sequences were determined in the TTV DNA-positive samples and evaluated using phylogenetic analysis which suggested that they could be divided into two main genotypes designated as genotype 1 and 2. There were five samples clustered into 3 hitherto unknown subtypes of genotype 2. We concluded that (1) although TTV infection is widespread among both groups and there is a statistical difference of TTV infection between them, no hepatic damaging evidence and correlation with certain liver disease could be found in this study, suggest that TTV may not be major cause of liver disease, (2) GBV-C infection is frequent, but the virus is not the cause of liver diseases, and (3) new subtypes of TTV may exist in Shanghai, China.     

Prevalence and phylogenetic characterisation of TT-virus in the blood donor population of Auckland, New Zealand

TT-virus (TTV, patient initials: T.T.), a novel DNA virus, was first isolated in Japan in 1997 from serum of a patient with post-transfusion hepatitis of unknown aetiology. To date, the contribution of TTV to liver disease remains doubtful. The potential for transmission via blood and blood products makes it essential to establish the prevalence of TTV viraemia in the blood donor population. 413 blood donor serum samples were chosen randomly, the DNA was extracted and TTV-specific DNA amplified by nested polymerase chain reaction (PCR). TTV infection was present in 13 out of 413 (3.15%) blood donors in the Auckland region of New Zealand using a set of primers targeting open reading frame (ORF) 1. These 13 amplification products (264 bp) were sequenced and TTV genotypes determined. Alignment with published TTV sequences showed that seven (53.8%) of the thirteen positive serum samples belonged to genotype 1, five (38.5%) belonged to genotype 2 and one (7.7%) could not be classified as either genotype 1 or 2. One hundred twenty-seven blood donor serum samples were retested with a second set of primers targeting the 5' region of the TTV genome in a single round PCR. Forty-three samples were positive for TTV DNA with these primers resulting in a prevalence of 37%. The data demonstrate that TTV is present among New Zealand blood donors and support the need for further investigation into the natural history of TTV infection.     

TT Virus Infection in French Hemodialysis Patients: Study of Prevalence and Risk Factors

The TT virus (TTV) is a recently discovered DNA virus which was first identified in patients with non-A to -G hepatitis following blood transfusion. In this study, we tested 150 attendees of two hemodialysis (HD) units of the public hospitals of Marseilles, France, for the presence of TTV genome by using a PCR-based methodology. The overall prevalence of TTV viremia was 28% (compared to 5.3% in blood donors from the same region). We demonstrated the existence of chronic infections and superinfections by strains belonging to different genotypes. The prevalence of infection was higher in patients originating from Africa, in patients with previous blood transfusion or organ transplantation, in patients with antibody to hepatitis B core antigen, and in those with diabetes mellitus. A high prevalence of TTV infection (50%) was also observed in a population of patients with diabetes mellitus but without renal disease. No significant relationship was found between TTV viremia and hepatitis C virus or GB virus C, transaminases, age, sex, and duration of HD treatment. The PCR amplification products (located in open reading frame 1 of the TTV genome) were sequenced. These genomic sequences were submitted to phylogenetic analysis by using the Jukes-Cantor algorithm for distance determination and the neighbor-joining method for tree building. In several instances, sequences from viruses isolated in a HD unit were grouped in the same phylogenetic cluster. These results together with the different distribution of cases in the two HD units suggest there is viral transmission within each.     

SEN virus infection does not affect the progression of non-A to -E liver disease

SEN virus (SEN V) was discovered recently as a potential causative agent of non-A, non-B, non-C, and non-E (non-A to -E) hepatitis. The aim of this study was to obtain information about the prevalence of this virus in Japan and its association with non-A to -E liver disease. Sixty-seven patients hospitalized for non-A to -E liver disease, including hepatocellular carcinoma (19 patients), cirrhosis (7 patients), chronic hepatitis (18 patients), and acute hepatitis (23 patients), were tested, along with 49 blood donors. The patients were admitted to Nihon University Hospital between 1991 and 1998. SEN V DNA was detected by a nested polymerase chain reaction, targeting the 5' untranslated region. SEN V DNA was detected in 14 of 49 (28.6%) blood donors and in 33 of 67 (49.3%) patients with non-A to -E liver disease. The prevalence of SEN V DNA was similar among patients with various liver diseases, including hepatocellular carcinoma (42.1%), cirrhosis (57.1%), chronic hepatitis (55.6%) and acute hepatitis (47.8%) and among blood donors (28.6%). There were no significant differences in the clinical profiles of patients with SEN V DNA-positive or -negative chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Similarly, there were no significant differences in the clinical profiles between patients with SEN V DNA-positive and -negative acute hepatitis. In conclusion, SEN V infection is present among many blood donors and is common in patients with non-A to -E liver disease. There are insufficient data to prove a causal role for SEN virus infection in non-A to -E liver disease.     

Prevalence of TT virus infection in Italian dialysis patients

OBJECTIVE: A novel DNA virus, transfusion-transmitted virus (TTV) is identified from the serum of a patient from acute hepatitis non-A-E. Few reports have been published on patients with renal disease. Patients on dialysis were at high risk of blood-borne viral infections and little is known about the prevalence of this virus in dialysis patients. In order to verify the prevalence of infection from TTV in these patients, we have examined the incidence of TTV in Italian patients with dialysis. METHODS: Serum samples of 85 patients and 65 healthy individuals were examined. In order to evidence the presence of the TTV virus, a method of the seminested polymerase chain reaction (PCR) with TTV-specific primers derives from the N22 region deIl'ORF-1 of the virus has been used and products were analyzed by agarose-gel electrophoresis. All serum samples were also analyzed to markers HBV and HCV. RESULTS: The prevalence of TTV DNA in dialysis patients [35/85 (41.7%)] was significantly higher than in healthy population [7/65 (10.7%)]. Among TTV positive dialysis patients, HCV coinfection was present in six cases. The positivity rate for TTV-DNA tends to increase with age. CONCLUSION: Transfusion-transmitted virus had a high prevalence in Italian-dialysis patients. In our study the virus did not have an important clinical effect on patients; but remains the possibility that it may aggravate liver disease caused by HCV. However, the question of whether TTV infection might have a possible effect on dialysis patients requires further investigation in larger groups.     

Development of a TT virus DNA quantification system using real-time detection PCR

Although TT virus (TTV) was isolated from a cryptogenic posttransfusion hepatitis patient, its pathogenic role remains unclear. It has been reported that the majority of the healthy population is infected with TTV. To elucidate the differences between TTV infection in patients with liver diseases and TTV infection in the healthy population, a quantification system was developed. TTV DNA was quantified by a real-time detection PCR (RTD-PCR) assay on an ABI Prism 7700 sequence detector. With this system, TTV DNA was quantified in 78 hepatitis C virus (HCV)-infected patients (63 with elevated serum alanine aminotransferase [ALT] levels and 15 with normal ALT levels) and in 70 voluntary blood donors (BDs). The quantification range was 2.08 to 7.35 log copies/ml. The intra-assay and interassay coefficients of variation were 0.37 to 6.33% and 0.60 to 7.07%, respectively. The mean serum TTV DNA levels in the HCV-infected patients with both elevated and normal ALT levels and BDs were 3.69 +/- 0.89, 3.45 +/- 0.76, and 3.45 +/- 0.67 log copies/ml, respectively. Comparison of the serum TTV DNA levels among the HCV-infected patients revealed that they were not related to the serum ALT and HCV core protein levels or to the histopathological score on liver biopsy. This study showed that (i) the RTD-PCR assay for the detection of TTV was accurate and had a high degree of sensitivity, (ii) the mean serum TTV DNA level was similar among HCV-infected patients, irrespective of their ALT level, and also among BDs, and (iii) a high serum TTV DNA level does not affect the serum ALT and HCV levels or liver damage in HCV-infected patients.     

Transmission of hepatitis C virus by organ transplantation.

BACKGROUND. Liver disease is a frequent and major complication after organ transplantation. We sought to determine whether hepatitis C virus (HCV) is transmitted by organ transplantation and whether it causes post-transplantation liver disease. METHODS. Serum samples from all cadaver organ donors to the New England Organ Bank between 1986 and 1990 were screened retrospectively for antibodies to HCV (anti-HCV) by enzyme-linked immunosorbent assay (ELISA). We reviewed the hospital records of all recipients of organs from anti-HCV-positive donors for evidence of liver disease. Serum samples from recipients obtained before transplantation and during follow-up were analyzed for anti-HCV. RESULTS. Of 716 organ donors, 13 (1.8 percent) were positive for anti-HCV. Their organs (19 kidneys, 6 hearts, and 4 livers) went to 29 recipients. Non-A, non-B hepatitis developed after transplantation in 14 of the 29 (48 percent), for a prevalence 7.4 times the 6.5 percent prevalence after transplantation from untested donors that was previously reported by two institutions in the organ bank (P less than 0.0001). The liver disease began a mean of 3.8 months after transplantation and became chronic in 12 patients; the other 2 had subfulminant hepatic failure. Liver disease was more frequent in the patients who had received antilymphocyte preparations (P = 0.04). HCV was the cause of the post-transplantation liver disease in 12 of the 13 recipients (92 percent) for whom serum samples were available. Anti-HCV was detected by ELISA in eight and enzyme immunoassay in one; in three others, HCV RNA was detected by polymerase chain reaction in serum samples obtained after transplantation. CONCLUSIONS. Organ transplantation can transmit hepatitis C. This raises serious questions about the continued acceptance of organs from donors positive for anti-HCV.     

Detection of TT virus sequences in children with liver disease of unknown etiology

DNA sequences of TT virus (TTV) in 55 serum samples taken from 20 children with liver disease of unknown etiology (16 with acute liver disease, 2 with fulminant hepatitis, and 2 with chronic liver disease) and from 35 healthy children as controls were examined by using the hemi-nested polymerase chain reaction (PCR). The PCR was carried out using the established primers (NG059, NG061, NG063) to amplify TTV DNA sequences. The sequences were detected in 6 of the 20 patients (30.0%) with liver disease and in 5 of the 35 healthy children (14.2%) by direct gel analysis. There was no significant difference between the prevalence of liver disease patients and controls. However, both patients with fulminant hepatitis and both patients with chronic hepatitis had TTV DNA sequences. Four of the six TTV isolates from liver disease patients were genotype 1a, whereas only one of the five TTV isolates from controls was genotype 1a. Although the study population was small, it is possible that genotype 1a of TTV might be more pathogenic than other genotypes in children.