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J I Esteban

Publications and source records attributed to J I Esteban.

At least 19 recordsLinked to original sources
PubMed1992

Interferon-alpha in acute posttransfusion hepatitis C: a randomized, controlled trial.

To assess the efficacy of interferon-alpha in acute hepatitis C, 28 patients with acute posttransfusion hepatitis were randomized to receive 3 million units of recombinant interferon-alpha three times weekly for 12 wk or no treatment. Biochemical, histological and serological parameters were monitored during 1 yr of follow-up. Serum ALT levels were normal at the end of therapy in 73% of treated patients and only in 38% of control patients (p = 0.06); these differences disappeared at 6 and 12 mo of follow-up. Anti-hepatitis C virus seroconversion occurred later and at a lower rate in the group of patients who received interferon-alpha. Treated patients had a trend toward less severe hepatic lesions with lower histological activity as compared with the control group, but no statistical differences were observed. No severe side effects of interferon-alpha were detected during the study. In summary, a 3-mo course of interferon-alpha in acute hepatitis C is safe and might have some effect in diminishing disease activity only during the treatment period; however, and probably because of a small sample size, no benefit of interferon-alpha in the long-term outcome of this disease was demonstrated.

Adolescent↗
PubMed1992

Evaluation of anti-HCV positive blood donors identified during routine screening.

Of 30,231 donors tested, 368 (1.2%) were anti-HCV positive. Of these, 254 have been evaluated, with the following results: only 25% have a history of parenteral risk, seroprevalence increases with age and approximately 80% of those that are anti-HCV positive in our population are probably infected with HCV. In addition, an unexpectedly large number of these persons have chronic and/or severe liver disease and will require combined diagnostic approaches for accurate evaluation.

Age Factors↗
PubMed1992

Hepatitis C virus (HCV) circulates as a population of different but closely related genomes: quasispecies nature of HCV genome distribution.

Sequencing of multiple recombinant clones generated from polymerase chain reaction-amplified products demonstrated that the degree of heterogeneity of two well-conserved regions of the hepatitis C virus (HCV) genome within individual plasma samples from a single patient was consistent with a quasispecies structure of HCV genomic RNA. About half of circulating RNA molecules were identical, while the remaining consisted of a spectrum of mutants differing from each other in one to four nucleotides. Mutant sequence diversity ranged from silent mutations to appearance of in-frame stop codons and included both conservative and nonconservative amino acid substitutions. From the relative proportion of essentially defective sequences, we estimated that most circulating particles should contain defective genomes. These observations might have important implications in the physiopathology of HCV infection and underline the need for a population-based approach when one is analyzing HCV genomes.

Amino Acid Sequence↗
PubMed1991

High rate of infectivity and liver disease in blood donors with antibodies to hepatitis C virus.

OBJECTIVE: To determine the epidemiologic, clinical, serologic, and histologic importance of antibodies to hepatitis C virus (anti-HCV) in blood donors. DESIGN: Cross-sectional identification and prospective evaluation of seropositive donors; retrospective assessment of infectivity; and nested case-control study for risk factors. SETTING: Liver unit of a referral-based university hospital. SUBJECTS: Of 30,231 consecutive donors, 368 (1.2%) were found to be anti-HCV-reactive by enzyme-linked immunosorbent assay (ELISA). Two hundred and fifty-four of these 368 donors were evaluated for risk factors by comparison with 284 age- and sex-matched controls. Eighty-six spouses of seropositive donors were also evaluated. MEASUREMENTS AND MAIN RESULTS: Twenty-four percent of the seropositive donors had a history of percutaneous exposure to blood. This rate increased to 45% when only those donors confirmed to be anti-HCV positive by a second-generation recombinant immunoblot assay (RIBA-2) were considered. A family history of liver disease (odds ratio, 2.8; 95% Cl, 1.6 to 4.8), previous blood transfusion (odds ratio, 6.1; 95% Cl, 3 to 12.5), and a history of tattooing or intravenous drug abuse (odds ratio, 8.4; 95% Cl, 2.3 to 31) were associated with anti-HCV seropositivity. An elevated alanine aminotransferase (ALT) level was found in 58% of the seropositive donors. Of the 150 donors tested, 104 (69%; Cl, 62% to 77%) were confirmed by RIBA-2 to be anti-HCV positive. Of the 105 donors who had a biopsy, 16% had normal histologic findings, 11% had minimal changes, 21% had chronic persistent hepatitis, 45% had chronic active hepatitis, and 7% had active cirrhosis. All 77 donors with RIBA-2-confirmed seropositivity had histologic abnormalities. Of 43 donors evaluated in an infectivity study, 82% were implicated in previous HCV transmission. Only 2.3% of the spouses were anti-HCV positive. The ELISA, RIBA-2, and ALT results correlated with infectivity and abnormal histologic findings. CONCLUSIONS: In our geographic area, almost 70% of donors who are anti-HCV positive by ELISA are confirmed to be positive by RIBA-2; most of these donors appear to be chronic carriers of HCV and have substantial liver disease.

Adolescent↗
PubMed1991

[Hepatitis C].

Explore the source record for details and available documents.

Hepacivirus↗
PubMed1990

Evaluation of antibodies to hepatitis C virus in a study of transfusion-associated hepatitis.

BACKGROUND: The hepatitis C virus (HCV) is now known to be the chief cause of transfusion-associated non-A, non-B hepatitis, but the prevalence of HCV among blood donors and the frequency of transmission by blood transfusion are unknown. METHODS: To assess the sensitivity and specificity of a test for antibody to HCV, we tested serum samples from participants in a large study of transfusion-associated hepatitis. Samples were obtained prospectively from consecutive adults undergoing open-heart surgery in Spain, but were tested retrospectively, after the antibody enzyme immunoassay for anti-HCV became available. RESULTS: Of 280 transfusion recipients given a total of 1109 units of blood, 27 (9.6 percent) had transfusion-associated non-A, non-B hepatitis (mean follow-up, 52 weeks) and 24 of the 27 seroconverted to anti-HCV-positive, whereas only 2 (0.8 percent) of the remaining transfusion recipients seroconverted. Among the 1044 donor specimens available for testing, 16 (1.5 percent) had anti-HCV antibody. Only 1 additional seropositive donor was found when 44 implicated donors who had been seronegative were retested 9 to 12 months later. Of the 16 recipients of anti-HCV-positive blood, 14 (88 percent) had transfusion-associated hepatitis and seroconverted to anti-HCV-positive. The remaining two recipients had neither hepatitis nor anti-HCV antibody. Among 25 patients with non-A, non-B hepatitis for whom all transfused blood was tested, 14 had received blood positive for anti-HCV. CONCLUSIONS: About 90 percent of blood donors with antibody to HCV have infectious virus in their blood. The screening of blood donors for anti-HCV antibody should prevent about half the cases of transfusion-associated hepatitis, but the donors with infectious virus who are anti-HCV-negative may remain seronegative for prolonged periods.

Adult↗
PubMed1990

[Diagnosis of acute hepatitis caused by herpes simplex virus using in situ hybridization].

A 50-year-old male without relevant past history was admitted because of fever lasting for 23 days. Physical examination showed hepatomegaly and splenomegaly without other findings. Laboratory studies only revealed mildly abnormal hepatic enzymes. The remaining investigations (markers, serologies, antinuclear antibodies, blood and urine cultures) were negative. Chest and abdomen X-ray films were normal. In abdominal echogram a homogeneous liver without space occupying lesions was seen, and computed tomography disclosed enlarged liver, spleen and lymph nodes. Needle hepatic biopsy was reported as showing reactive hepatitis. Although clinically meningeal antibody seroconversions were not found, DNA chains of cytomegalovirus, Epstein-Barr virus, hepatitis B virus and herpes virus simplex were investigated with the in situ hybridisation technique. Its result was a strongly positive hybridisation for herpes virus and negative for the other investigated viruses.

Acute Disease↗
PubMed1989

Clinical implications of positive tests for antibodies to human immunodeficiency virus type 1 in asymptomatic blood donors.

Of 693,000 volunteer blood donors in Washington, D.C., who were screened for infection with human immunodeficiency virus type 1 (HIV-1) from July 1985 through December 1988, 284 tested positive on both enzyme immunoassay and Western blot assay. To determine the clinical importance of confirmed positive test results in asymptomatic blood donors, we followed 156 donors with positive Western blot assays and 80 donors with positive enzyme immunoassays but negative or indeterminate Western blots at 6-month intervals for a mean of 28 months. As compared with Western blot-negative persons, those with positive Western blots were significantly more likely to be black, male, and first-time donors and to have a history of venereal disease, generalized lymphadenopathy on examination, CD4-cell counts lower than 0.4 x 10(9) per liter, IgG levels higher than 18 g per liter, and antibody to hepatitis B core antigen on initial evaluation. In 17 (11 percent) of the Western blot-positive donors, the disease progressed to Class IV (symptomatic disease), according to the Centers for Disease Control system. CD4 counts below 0.2 x 10(9) per liter, IgA levels above 4 g per liter, abnormal proliferative responses to tetanus toxoid, and positive viral cultures were the strongest predictors of disease progression. Among the 80 donors with repeatedly reactive assay results but either negative or indeterminate Western blot assays, there was no evidence of HIV exposure in their histories, physical examinations, or laboratory evaluations, and manifestations of HIV infection developed in none of them. We conclude that a small number of persons with HIV infection continue to donate blood, despite attempts to exclude them, but that donors who test positive on enzyme immunoassay but persistently negative or indeterminate on Western blot assay probably do not represent a risk for the transmission of HIV.

AIDS-Related Complex↗
PubMed1989

Hepatitis C virus antibodies among risk groups in Spain.

The frequency of hepatitis C virus (HCV) infection in Spain was assessed by means of a recombinant-based immunoassay for serum anti-HCV antibodies. 836 serum samples were tested from 676 patients selected according to their risk of blood-borne viral infections and presence of liver disease. Among patients at high risk of infection (with or without liver disease) anti-HCV antibodies were found in 85% of prospectively followed patients with post-transfusion non-A, non-B hepatitis, 62% of patients with chronic hepatitis or cirrhosis and a history of blood transfusion, 70% of haemophiliacs receiving replacement therapy, 70% of intravenous drug abusers, and 20% of haemodialysis patients. Only 8% of homosexual men infected with human immunodeficiency virus and 6% of female contacts of drug abusers were positive. Among patients with liver disease and no history of parenteral exposure to blood, anti-HCV antibodies were detected in 38% with cryptogenic, alcoholic, or primary biliary cirrhosis and in 44% with chronic active hepatitis. Among healthy subjects without risk factors for hepatitis the overall prevalence of anti-HCV was 1.2%.

Adolescent↗
PubMed1989

Chronic delta hepatitis: detection of hepatitis delta virus antigen in serum by immunoblot and correlation with other markers of delta viral replication.

To investigate the presence of serum hepatitis delta virus antigen by immunoblot and its correlation with other markers of active viral replication (intrahepatic hepatitis D antigen, IgM antibody to hepatitis D and serum hepatitis D virus RNA), we studied serum samples from 50 patients with chronic hepatitis D virus infection (38 with and 12 without intrahepatic hepatitis D antigen). Of the 38 patients with intrahepatic hepatitis D antigen, 27 (71%) had antigen detectable in serum by immunoblot, whereas only two were reactive by conventional enzyme-linked immunosorbent assay. Thirty-one (82%) patients were also positive for serum hepatitis D virus RNA by spot hybridization and 33 (87%) were positive for IgM anti-hepatitis D virus. All markers were simultaneously present in 24 patients. Circulating hepatitis D antigen was detected in one (8%), IgM anti-hepatitis D in seven (58%) and hepatitis D virus RNA in two (17%) of the 12 patients who had anti-hepatitis D in serum but not detectable hepatitis D antigen in liver. Hepatitis D antigen was not detected in serum of any of the 15 control patients. The results suggest that serum hepatitis D antigen as detected by immunoblot and serum hepatitis D virus RNA are similar in sensitivity for detection of active hepatitis D virus replication during chronic infection and constitute useful, sensitive and noninvasive tests for the diagnosis and monitoring of chronic hepatitis D virus infection.

Adolescent↗
PubMed1989

Comparison of four different antigen-capture assays for the detection of human immunodeficiency virus antigen (HIV-Ag).

Three enzyme immunoassays (EIA), two polyclonal and one monoclonal, and one polyclonal radioimmunoassay (RIA) for the detection of human immunodeficiency virus antigen (HIV-Ag) have been evaluated and compared. The three EIAs had similar sensitivity in detecting HIV viral lysate and were more sensitive than the RIA, which was the only assay with a one-step probing-detection format. However, the EIA that used a monoclonal anti-p24 as the capturing reagent was unable to detect any of the serial supernatant samples of a positive viral culture from an HIV-infected patient. Only the two polyclonal, non-p24-restricted assays were able to detect an unusual expression of HIV-Ag in the serum of an acute HIV-infected patient. Overall, the sensitivity of HIV-Ag capture assays was enhanced when (a) the capture antibody was polyclonal rather than monoclonal, (b) the polyclonal antibody was broad rather than p24-restricted, and (c) the probing-detecting procedure was in a two-step format rather than one-step format. In addition, the use of neutralizing assays to confirm the results was absolutely necessary.

Antibodies, Monoclonal↗
PubMed1988

Hepatitis B virus infection in Danish dentists. A case-control and follow-up study.

The authors determined the seroprevalence of hepatitis B virus markers among Danish dentists in 1985 in an effort to assess occupational risk factors. A case-control study approach was applied using pedodontists as zero-exposure controls. The study further allowed serologic and epidemiologic follow-up of dentists who participated in a similar study in 1976. The authors sought to determine whether exposure to hepatitis B virus in this population sometimes leads to immunization without infection (antibody to hepatitis B surface antigen (anti-HBs) positivity only). A total of 922 dentists (22% of all Danish dentists) gave blood; of these, 254 (28%) participated in the 1976 study. Serum samples were tested using commercial solid phase radioimmunoassays. The prevalences of anti-HBs and antibody to hepatitis B core antigen (anti-HBc) were 7.2% (95% confidence interval (CI) = 5.7-9.0) and 5.2% (95% CI = 3.8-6.6), respectively. Twenty-one dentists (31%) only had anti-HBs (without prior vaccination). Age-standardization of the two data sets (1976 and 1985) indicated no substantial change in seroprevalence. Private practitioners, especially those working in Copenhagen, had an increased odds ratio (OR) of being seropositive compared with that of pedodontists (OR = 3.0 (95% CI = 1.3-6.8) adjusted for age and sex and OR = 2.4 (95% CI = 1.1-5.2) adjusted for age and site of practice). The proportion attributable to occupational exposure was approximately 50%. In a logistic regression model, site of practice and type of specialty were associated with hepatitis B virus seropositivity (p = 0.01 and 0.05, respectively), whereas age, sex, hours of oral surgery per week, and use of gloves were not. Four persons had become seropositive in the follow-up study, for a seroconversion rate of 0.2% per year. Seven out of 18 dentists who were anti-HBs positive in 1976 were found to be anti-HBs negative in 1985. Most of these dentists had values below 10.0 units by S/N ratio (ratio of counts per minute of sample compared with the mean number of counts per minute of negative controls). The findings do not justify institution of a large-scale vaccination program for dentists, but there are certain subgroups of dentists which constitute candidates for vaccination.

Adult↗