A nationwide survey for hepatitis E virus prevalence in Japanese blood donors with elevated alanine aminotransferase

BACKGROUND: Although we reported two cases of transfusion‐transmitted hepatitis E in Japan, the prevalence of hepatitis E virus (HEV) in Japanese blood donors is not very clear. STUDY DESIGN AND METHODS: Blood samples of donors who were deferred from donation because of elevated alanine aminotransferase (ALT) levels were collected from all Japanese Red Cross Blood Centers and subjected to HEV tests. RESULTS: Among the 41 donors with elevated ALT levels higher than 500 IU per L in Hokkaido, HEV RNA was detected in 8 (19.5%) samples. In 1389 donor samples with ALT levels of higher than 200 IU per L in nationwide Japan, the numbers of positive HEV RNA, immunoglobulin M (IgM) anti‐HEV, and immunoglobulin G (IgG) anti‐HEV samples were 15 (1.1%), 14 (1.0%), and 45 (3.2%), respectively. Although RNA‐positive donors were predominantly male and found in any geographic area of Japan, they tended to be higher in number in eastern Japan including Hokkaido and lower in number in western Japan. Of the 23 HEV‐positive samples, 19 were Genotype 3 and 4 were Genotype 4. DNA sequences of the 9 isolates showed more than 98.5 percent homology with the known swine HEV isolates. In 1062 donor samples with ALT levels of 61 to 199 IU per L, the percentages of IgM and IgG anti‐HEV–positive samples were 0.1 and 2.7 percent, respectively, although there was no HEV RNA–positive sample. CONCLUSION: HEV markers (HEV RNA and anti‐HEV) were detected in donors with elevated ALT levels who were widely distributed over Japan. The prevalence and incidence were higher in eastern Japan than in western Japan.     

A search for hepatitis C virus polymerase chain reaction-positive but seronegative subjects among blood donors with elevated alanine aminotransferase

BACKGROUND: Previous studies reported the existence of hepatitis C virus (HCV) polymerase chain reaction (PCR)-positive but seronegative sera. This is not surprising in the case of window-phase specimens, because PCR can detect HCV RNA many weeks before the appearance of antibody. To determine whether such sera can also be found in chronically infected subjects, a high-risk population of blood donors with elevated alanine aminotransferase was studied. STUDY DESIGN AND METHODS: Freshly frozen plasma from 301 donors with alanine aminotransferase > 100 IU per L was tested with PCR assays that were rigidly controlled for specificity and contamination, and with current and newer versions of assays for anti-HCV. Sera were classified as seropositive if positive in two screening assays and one supplemental assay or if positive in two screening assays and PCR. RESULTS: New versions of screening assays detected 100 percent of seropositive samples. A second-generation immunoblot assay detected 98 percent of seropositive sera, a second-generation recombinant immunoblot assay detected 96 percent, and an enzyme immunoassay for antibody to the envelope protein of HCV detected 98 percent. Fifty-one of 54 seropositive sera were PCR positive. None of the 247 seronegative samples was reproducibly positive on PCR. CONCLUSION: No PCR-positive but seronegative donors were found in this high-risk donor population. The possible benefit of PCR screening of blood donors can be determined only by large-scale comparative testing of donor populations and may be limited to the detection of window-phase infections.     

Hepatitis C virus and GB virus C/hepatitis G virus viremia in Swedish blood donors with different alanine aminotransferase levels

BACKGROUND: Hepatitis C virus (HCV) is a known blood-borne hepatotropic virus for which antibody screening of blood donors is universally practiced. The newly identified GB virus C (GBV-C) and its strain variant hepatitis G virus (HGV) are of unknown pathogenic significance, and screening of blood donors for this agent has not yet been implemented. Polymerase chain reaction (PCR) is the most sensitive method for detecting HCV viremia and is the only method presently available for the diagnosis of GBV-C/HGV infection. STUDY DESIGN AND METHODS: RNA extracts of sera from 577 anti-HCV-negative blood donors (393 with elevated alanine aminotransferase [ALT] levels, 184 with normal ALT levels) were tested with nested PCR for HCV and GBV-C/HGV directed at the 5'-noncoding regions of the two viruses. RESULTS: One donor with elevated ALT was HCV PCR positive. This donor was anti-HCV negative when recruited to the study but subsequently developed anti- HCV. Of the 19 donors with GBV-C/HGV viremia in the series as a whole, 16 belonged to the group with elevated ALT levels and 3 to the group with normal ALT levels; the group difference in prevalence was nonsignificant (4.1% [16/393] vs. 1.6% [3/184; p = 0.20]). Phylogenetic analysis showed 16 of the GBV-C/HGV isolates to be classifiable as subtype 2a and three as subtype 2b. At follow-up 3 to 5 years later, 11 of 18 donors were still viremic. CONCLUSION: There was no significant difference in GBV-C/HGV viremia in the group with elevated ALT levels and the group with normal ALT levels. The frequency and subtype distribution in the present series were similar to those in other Western countries.     

Rare detection of hepatitis B and hepatitis C virus genomes by polymerase chain reaction in seronegative donors with elevated alanine aminotransferase

BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous.     

Limited utility of alanine aminotransferase screening of hepatitis C antibody-screened blood donors

BACKGROUND: The introduction of hepatitis C virus (HCV) screening has significantly reduced the frequency of posttransfusion hepatitis C. To examine the current added value of alanine aminotransferase (ALT) screening, all donor screening at two large blood centers was reviewed. STUDY DESIGN AND METHODS: From July 1991 through March 1994, 1,258,000 allogeneic blood donors were screened by enzyme immunoassay for anti- HCV: 343,000 donations by the first-generation test (HCV 1.0) and 915,000 donations by the second-generation test (HCV 2.0). Donations with positive EIA results were confirmed with a recombinant immunoblot assay. RESULTS: Of these donors, 1,637 (0.13%) were confirmed as HCV- positive and 21,666 (1.72%) had elevated ALT. To estimate the additional margin of safety due to ALT screening, all donors who seroconverted were reviewed, and those donors who had elevated ALT but were HCV negative on a previous donation were identified. One hundred eleven HCV seroconversions were observed: 19 seroconversions from HCV 1.0-negative to HCV 1.0-confirmed-positive, 82 apparent seroconversions from HCV 1.0-negative to HCV 2.0-confirmed-positive, and 10 seroconversions from HCV 2.0-negative to HCV 2.0-confirmed-positive. The number of apparent HCV 1.0-negative to HCV 2.0-positive seroconversions was much greater than expected, which reflected the increased sensitivity of HCV 2.0. Only 15 donors were identified who had an elevated ALT on a previous HCV-negative blood donation, and all of these were among those who apparently seroconverted from HCV 1.0- negative to HCV 2.0-confirmed-positive. Out of the 10 HCV 2.0- seroconverting donors, no donor was found who was initially HCV 2.0 negative with elevated ALT and later was HCV 2.0 positive; nor were such donors found among 4 additional HCV 2.0-seroconverting donors. CONCLUSION: With the introduction of HCV 2.0 screening. ALT appears to have little value as a surrogate test for hepatitis C, and ALT testing was unable to detect any donors who later seroconverted, as detected by HCV 2.0.     

Hepatitis B virus nucleic acid testing in Chinese blood donors with normal and elevated alanine aminotransferase

BACKGROUND: Nucleic acid testing (NAT) is currently not a routine donor test in China. The aim of this study was to evaluate the current residual risk of hepatitis B virus (HBV) transmission and the value of ALT testing in preventing HBV infection. STUDY DESIGN AND METHODS: From January 2008 to September 2009, a total of 5521 qualified donations by routine screening and 5034 deferred donations due to elevated ALT alone were collected from five blood centers. Samples were tested for HBV DNA by triplex individual‐donation (ID)‐NAT (ULTRIO assay, on the TIGRIS system, Novartis Diagnostics). HBV NAT–reactive samples were further analyzed by HBV serology, alternative NAT, and viral load and were diluted to simulate if they could be detected in a minipool‐NAT. RESULTS: There was no significant difference in the HBV NAT–yield rate between the qualified donations group (5/5521) and the deferred donations group (4/5034). Of these nine potential HBV‐yield cases, one donor (11%) was a possible HBV window‐period donor, one (11%) was a chronic HBV carrier, and seven (78%) had probable or confirmed occult HBV infections. Of seven potential HBV‐yield cases quantified, the viral loads were less than or equal to 70.0 IU/mL. Minipool testing (minipools of 4, 8, and 16 donations) would miss 43% to 79% of the nine HBV‐yield donations. CONCLUSIONS: Based on our findings in qualified donations, we estimate that the nationwide implementation of ID‐NAT testing for HBV DNA in China would detect an additional 9964 viremic donations per year. ALT testing seems to have no significant value in preventing transfusion‐transmitted HBV infection. ID‐NAT versus simulated minipool‐NAT using the ULTRIO test demonstrates the benefit to implement a more sensitive NAT strategy in regions of high HBV endemicity.     

The persistence and significance of elevated alanine aminotransferase levels in blood donors

The level of alanine aminotransferase (ALT) in blood donors has been related to the frequency of posttransfusion hepatitis in recipients. Sixty-seven donors with elevated ALT levels were evaluated to define the duration and significance of the elevation. The ALT level remained elevated in 41 donors (61%) for a mean interval of 9 months. The ALT level was greater than the aspartate aminotransferase in all of the donors. Alcohol intake did not correlate with ALT level. Donors with persistently elevated ALT levels had a significantly higher mean percent ideal body weight (128 +/− 3.9) than donors whose ALT level became normal (116 +/− 3.1). Nine donors with elevated ALT levels for at least 6 months had needle biopsies of the liver. Seven had prominent fatty vacuolization of hepatocytes without evidence of alcoholic hepatitis. One biopsy demonstrated chronic persistent hepatitis. No other cause for the elevated ALT levels could be identified. An overweight male donor with an isolated ALT elevation may need no further investigation unless clinical evaluation suggests a source of liver injury.     

Long-term follow-up of and infectivity in blood donors with hepatitis C antibodies and persistently normal alanine aminotransferase levels

BACKGROUND: Little is known about the prevalence of serum hepatitis C virus (HCV) RNA in blood donors with HCV antibodies and persistently normal alanine aminotransferase (ALT) levels. STUDY DESIGN AND METHODS: Thirty-nine anti-HCV-positive donors with normal ALT on four determinations at 3-month intervals were further tested monthly for 6 months, and they had normal ALT values. The presence of HCV RNA was determined in these 39 donors. RESULTS: Serum HCV RNA was detected in 16 of 39 donors, 14 of 14 who reacted on second-generation recombinant immunoblot assay (RIBA-2) and 2 of 15 who were indeterminate. None of the 10 RIBA-2-nonreactive donors had evidence of viremia. The 15 RIBA-2- indeterminate samples were tested with third-generation RIBA (RIBA-3); the results showed reactivity in 5 (including the 2 HCV RNA positive), an indeterminate pattern in 7, and nonreactivity in 3 (all RNA negative). Among HCV RNA-positive subjects, mean age (p < 0.05), mean ALT (p < 0.001), signal-to-cutoff (S:CO) ratio on second-generation enzyme-linked immunosorbent assay (p < 0.001), and gamma globulin levels (p < 0.05) were higher than those among HCV RNA-negative subjects. During 6 additional months of ALT monitoring, completed by 36 of 39 donors, increased values were detected in 6 (5 HCV RNA positive). In 4 of those 6, however, ALT levels were less than 1.5-fold the upper normal limit. HCV RNA results were unchanged at the end of 1-year follow-up. CONCLUSION: Forty-one percent of anti-HCV-positive donors with persistently normal ALT had active HCV infection. Long-term ALT monitoring allowed the detection of significantly increased enzyme values in only 2 of 16 viremic donors. Reactivity on RIBA-2 or -3, greater age, mean ALT levels in the upper range of normal, higher S:CO ratio on second-generation enzyme-linked immunosorbent assay, and higher gamma globulin levels were predictive of viremia.     

Detection of three types of hepatitis C virus in blood donors: investigation of type-specific differences in serologic reactivity and rate of alanine aminotransferase abnormalities

The serologic reactivity and epidemiology associated with different hepatitis C virus (HCV) variants were investigated in a cohort of 113 anti-HCV-positive donors. In Scotland, HCV type 1 accounted for one- half of all infections; 40 percent of subjects were infected with HCV type 3, and the remainder were infected with type 2. Reactivity with the NS-4-encoded antigens in the first-generation anti-c100 assay was absent in 68 percent of donors infected with types 2 and 3, as compared with 10 percent for those infected with type 1. Even when combined with surrogate marker testing, first-generation tests would have failed to detect 12 percent of HCV-infected blood donors. The age distribution, incidence of past infection with hepatitis B virus, and reported risk factors were similar in donors infected with types 1 and 3 (mean ages were 31.9 and 29.9; 18 and 17.5% were positive for antibody to hepatitis B core antigen; and 47 and 48% had past intravenous drug abuse). However, the distributions of alanine aminotransferase levels were significantly different in those infected with type 3 (abnormally raised in 83%) and those infected with type 1 (55% abnormal alanine aminotransferase; p < 0.05) or type 2 (60%; p < 0.01) and those who were nonviremic (8%; p < 0.0001). These data suggest that HCV type 1 is the most common HCV infection in blood donors and that infection with HCV type 3 may be associated with more severe liver disease, because of more recent infection or because of a greater inherent pathogenicity of type 3 variants.     

Co-variation of alanine aminotransferase levels with relative weight in blood donors.

The association between alanine aminotransferase (ALAT) and body mass, sex and age was examined in 6036 consecutively tested blood donors. ALAT, age and body mass were higher in male donors than in female donros. The non-normal ALAT distribution curve normalized after 1n transformation, which made statistical analysis of the data more feasible. Multiple regression analysis demonstrated that ALAT was influenced by sex and relative weight, in that order, and very poorly by age. It is concluded that obesity is a major cause of raised ALAT in this predominantly healthy donor population.     

Risk factors associated with hepatitis B or C markers or elevated alanine aminotransferase level among blood donors on a tropical island: the Guadeloupe experience

Donated blood is currently screened for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc), antibody to hepatitis C virus (anti-HCV), and alanine aminotransferase (ALT) levels to prevent posttransfusion hepatitis. A prospective study of 2368 blood donors was carried out in Guadeloupe (French West Indies) with a view to determining the risk factors associated with serologic abnormalities. Blood donors included in the study had to complete a questionnaire. Statistical analysis was performed on the data thus obtained: 571 donations (24%) were positive for at least one of the four analyzed markers. The results were that 3.2 percent were positive for HBsAg, 22 percent for anti-HBc, and 0.8 percent for anti-HCV, and 1.4 percent had ALT > or = 45 IU per L. A good correlation was found between anti-HCV and elevated ALT. Transfusion history and two socioeconomic categories (working class, military personnel) were found to be risk factors. Other risk factors were lifelong residence in Guadeloupe (with risk increasing with the number of years), birthplace and current residence in the southern part of the island, and the existence of gastrointestinal discomfort unrelated to viral hepatitis (odds ratio = 2.98). The results of this study illustrate the difficulty of implementing a preventive policy against posttransfusion hepatitis in a tropical area. The unique epidemiologic situation of Guadeloupe as regards hepatitis B virus has led to more restrictive criteria for the acceptance of blood donors.     

Declining value of alanine aminotransferase in screening of blood donors to prevent posttransfusion hepatitis B and C virus infection. The Retrovirus Epidemiology Donor Study

BACKGROUND: Since the mid-1980s, blood banks in the United States have screened donors for elevated alanine aminotransferase (ALT) in an effort to prevent posttransfusion hepatitis. The present study was designed to quantitate the residual value of ALT screening following the implementation of hepatitis C virus (HCV) assays. STUDY DESIGN AND METHODS: Two approaches were used. First, a database of 2.3 million donations made by 586,507 volunteer blood donors between 1991 and 1993 was used to compare the incidence of seroconversion to hepatitis B virus (HBV) and HCV marker positivity in donors with elevated ALT values and with normal ALT values. Second, the duration of ALT elevation prior to HBV and HCV seroconversion was determined from 34 well-documented cases of posttransfusion HBV and HCV; elevated-ALT window periods were multiplied by rates of HBV and HCV incidence in donors to project the yield of ALT screening. Predictive value and cost- effectiveness analyses were also performed to compare the value of ALT screening before and after HCV screening was implemented. RESULTS: Both approaches indicate that ALT testing does not detect HBV in the window phase but does currently identify approximately 3 HCV window-phase donations per 1 million donations; this contrasts with ALT detection of approximately 1800 HCV-infectious units per 1 million donations prior to anti-HCV screening. Currently, only 8 in 10,000 donated units with elevated ALT (negative anti-HCV) are infected with HCV. The cost of continued ALT screening was estimated at $7,931,000 per quality- adjusted year of life saved. CONCLUSION: The yield, predictive value, and cost-effectiveness of ALT screening of blood donors have declined dramatically with the implementation of progressively improved anti-HCV assays. ALT screening of volunteer blood donors should be discontinued.     

Influence of viral load and alanine aminotransferase on viral genetic heterogeneity in patients with chronic hepatitis C virus infection

BACKGROUND/AIM: Hepatitis C virus (HCV) populations in vivo consist of genetically different heterogeneous mixtures defined as 'quasispecies', which vary in the hypervariable region 1 (HVR1) mostly. To further address the role of quasispecies diversity in hepatitis C infection, this study aimed to evaluate the influence of ALT, viral load and genotypes on quasispecies heterogeneity in patients with HCV infection. METHODS: Thirty-six chronic hepatitis C patients with high levels of alanine aminotransferase (ALT) were studied. None of them received any antiviral therapy. HCV RNA serum levels, genotype and genetic heterogeneity were determined by branched-chain DNA assay, restriction fragment length patterns and RT-PCR single-strand conformational polymorphism analysis of HVR1, respectively. RESULTS: Twenty-eight patients had genotype 1b (28/36; 78%), 6 patients had genotype 1a (6/36; 17%), 1 patient was 2a (1/36; 3%) and genotype could not be determined in 1 patient. The patients were categorized into two groups according to the number of bands representing the dominant strains in the circulation: group A with 2 bands having 1 strain (14/36 patients; 39%) and group B with more than 2 bands indicating more than 1 strain (22/36 patients; 61%). The serum viremia and ALT levels for these groups were 11 +/- 8.8 and 5.3 +/- 4.6 mEq/ml (p < 0.05), and 79 +/- 20, and 127 +/- 80 IU/l (p < 0.05), respectively. CONCLUSION: The results of this study suggest that hepatitis C patients having 1 dominant strain in the circulation may show a relatively weaker immune response resulting in lower ALT and higher viremia levels, whereas patients with high degrees of virus quasispecies diversity have higher ALT levels and a more active immune response causing the selection of new genome variants and depressing viral replication partly.     

Correlation of viral RNA, alanine aminotransferase, and histopathology in hepatitis C virus-associated hepatitis.

BACKGROUND: Hepatitis C virus (HCV) infection is usually monitored by the level of alanine aminotransferase (ALT) and histopathological changes in liver biopsy specimens. However, accumulating data indicate these parameters are not always correlated with disease progression or the response of HCV infection to therapy. MATERIALS AND METHODS: Using the Amplicor PCR Monitor Test Kit (Roche Diagnostic Systems, Branchburg, NJ), HCV RNA level was measured in 38 patients with positive anti-HCV antibodies and in 21 of those patients after interferon treatment. The grade and stage of histological changes on hematoxylin and eosin-stained sections of liver biopsy specimens were evaluated on a scale of 1 to 4. In each case, the HCV RNA level was compared with the histological grade or stage and level of ALT and statistically analyzed by Student's t-test. RESULTS: ALT level did not correlate with pretreatment and posttreatment levels of HCV RNA or histopathological changes. However, there was a statistically significant correlation between HCV RNA and histological grade (P,.05). CONCLUSION: HCV RNA measurement is a better means of determining and monitoring HCV infection than either ALT level or histopathological characteristics and may provide insight into hepatic injury caused by HCV infection even without an invasive liver biopsy.     

Antibodies to hepatitis B core antigen in blood donors screened for alanine aminotransferase level and hepatitis non-A, non-B in recipients

Four-hundred and seventeen patients undergoing open-heart surgery were followed for more than 9 months after transfusion. All 2270 blood units transfused had alanine aminotransferase levels less than or equal to 30 U/l. Blood units positive for antibodies to hepatitis B core antigen (anti-HBc) were more frequently associated with recipient hepatitis non-A, non-B (HNANB) (13.7%) than anti-HBc-negative units (4.2%) (p less than 0.001). The frequency of HNANB among recipients of at least 1 anti-HBc-positive blood unit (8/79, 10.1%) was fivefold greater than among recipients of exclusively anti-HBc-negative blood units (7/338, 2.1%) (p less than 0.01). In this study the exclusion of donors positive for anti-HBc (4.2%) might have reduced the incidence of recipient HNANB by 42 percent. These results support the introduction of anti-HBc donor screening to prevent recipient HNANB.     

血清丙氨酸转氨酶正常的慢性丙型肝炎的治疗

丙型肝炎病毒（HCV）感染的流行较为广泛，呈全球性分布。慢性丙型肝炎患者如得不到及时和合理的治疗，可发展为肝硬化、肝细胞癌。对血清丙氨酸转氨酶（alanine aminotransferase，ALT）升高的慢性丙型肝炎患者的治疗早已取得共识，即应采取积极的抗病毒治疗；但对ALT正常的慢性丙型肝炎患者是否应该常规接受抗HCV治疗，长期以来一直存在分歧。本文对ALT正常的慢性丙型肝炎的流行病学、自然史和治疗等研究进展作简要的介绍。