. Almroth G, Ekermo B, Månsson A‐S, Svensson G, Widell A. (University Hospital of Linköping; University Hospital of Malmö, Sweden) Detection and prevention of hepatitis C in dialysis patients and ...renal transplant recipients. A long‐term follow up (1989–January 1997). J Intern Med 2002; 251: 119–128.
Background. Hepatitis C is frequent problem in dialysis wards.
Design. A long time (1989–97) follow up of hepatitis C virus (HCV) infection in a Swedish nephrology unit was performed with anti‐HCV screening, confirmatory antibody tests, viral RNA detection and molecular characterization. Case histories were reviewed with focus, onset of infection, liver morbidity and mortality.
Results. In October 1991, 10% (19 of 184) of the patients in the unit (haemodialysis‐, peritoneal dialysis and transplanted patients) were verified or suspected HCV carriers, whilst the number at the end of 1996 was 8% (13 of 157). Most patients were infected before 1991 but only in one case from a known HCV‐infected blood donor. No new HCV infections associated with haemodialysis occurred during the study period. A total of 13 of 24 viremic patients had HCV genotype 2b, a pattern suggesting nosocomial transmission. This was further supported by phylogenetic analysis of HCV viral isolates in seven. HCV viremia was also common in patients with an incomplete anti‐HCV antibody pattern as 8 of the 12 indeterminant sera were HCV‐RNA positive.
Conclusions. Awareness, prevention, identification of infected patients and donor testing limited transmission. Indeterminant recombinant immunoblot assays (RIBA)‐results should be regarded with caution as a result of the relative immunodeficiency in uremic patients. Our data indicate nosocomial transmission in several patients.
Voluntary non-remunerated repeat blood donors are perceived to be safer than the first time blood donors. This study was planned for follow-up of previous hepatitis C virus (HCV) test results of ...anti-HCV enzyme-linked immunosorbent assay (ELISA) reactive repeat blood donors. The aim was to suggest a protocol for re-entry of the blood donors who are confirmed HCV negative by nucleic acid test (NAT) and recombinant immunoblot assay (RIBA). A group of repeat voluntary donors were followed retrospectively who became reactive on a cross sectional study and showed HCV reactivity while donating blood regularly.
A total of 51,023 voluntary non remunerated blood donors were screened for anti-HCV ELISA routinely. If anybody showed positivity, they were tested by two ELISA kits (screening and confirmatory) and then confirmed infection status by NAT and or RIBA. The previous HCV test results of repeat donors reactive by anti-HCV ELISA were looked back from the records. Data of donors who were repeat reactive with single ELISA kit (in the present study) were analyzed separately from those reactive with two ELISA kits (in the present study).
In this study, 140 (0.27%) donors who were reactive by anti HCV ELISA were included. Out of them, 35 were repeat voluntary donors and 16 (11.43%) were reactive with single ELISA kit. All 16 donors were reactive by single ELISA kit occasionally in previous donations. Their present ELISA positive donations were negative for HCV NAT and RIBA. A total of 19 (13.57%) donors were reactive with two ELISA kits. In their previous donations, the donors who were reactive even once with two ELISA kits were consistently reactive by the same two ELISA kits in their next donations also.
Donor sample reactive by only single ELISA kit may not be considered as infectious for disposal as they were negative by NAT and or RIBA. One time ELISA positivity was found probably due to ELISA kit specificity and sensitivity. Donors reactive with two ELISA kit should be discarded as there is a high positivity with NAT/ RIBA. However, donors reactive by two ELISA kits and negative by NAT and RIBA should be followed up and may not be deferred permanently.
Because of a high prevalence of hepatitis C virus (HCV) infection (10–20%) among veterans seeking care in Department of Veterans Affairs (VA) hospitals, current US military forces were evaluated for ...HCV infection. Banked serum samples were randomly selected from military personnel serving in 1997 and were tested for antibody to HCV (anti-HCV). Overall prevalence of anti-HCV among 10,000 active-duty personnel was 0.48% (5/1,000 troops); prevalence increased with age from 0.1% among military recruits and active-duty personnel aged <30 years to 3.0% among troops aged ≥40 years. Prevalence among 2,000 Reservists and active-duty troops was similar. Based on sequential serum samples from 7,368 active-duty personnel (34,020 person-years of observation), annual incidence of infection was 2/10,000. Of 81 HCV RNA-positive troops for whom genotype was determined, genotypes 1a (63%) and 1b (22%) predominated, as in the civilian population. These data indicate that HCV infection risk among current military forces is lower than in VA studies and the general civilian population aged <40 years. The low level of HCV infection may be attributed to infrequent injection drug use in the military due to mandatory testing for illicit drugs prior to induction and throughout military service.
The diagnosis of acute hepatitis C virus (HCV) infection relies on documented positive‐seroconversion of HCV antibody (anti‐HCV). Because of the detection of seroconversion at an earlier stage by ...second or third generation anti‐HCV enzyme immunoassays (EIA), the diagnosis of acute hepatitis C (AHC) may be underestimated. The aim of this study was to evaluate whether rising anti‐HCV titre could be used to diagnose AHC or not. Eighteen patients with a clinical diagnosis of acute hepatitis C were enrolled, including eight cases with documented seroconversion to anti‐HCV and 10 cases with clinically suspected acute hepatitis C. Four chronic hepatitis C patients with acute exacerbation were selected as a control group. Serial sera were assayed with a third generation anti‐HCV (AxSYM, version 3.0; Abbott, Chicago, IL, USA) and recombinant immunoblot assays (RIBA; Chiron HCV 3.0 Strip; Immunoblot, Emeryville, CA, USA) and the titre of anti‐HCV expressed as signal/cutoff (S/CO) ratio and the RIBA patterns were correlated. Seven of eight documented AHC (one lacking the initial serum) and five of 10 clinically suspected AHC showed a rising pattern of S/CO values. The initial S/CO values on the first visit were less than 40 in 14 of 18 cases. The RIBA pattern shifted from negative/indeterminate to positive in five of seven documented AHC and 4 of 10 clinically suspected AHC cases. Fifteen of 18 cases had seroconversions of at least one antibody, whilst 85.7% showed a rising S/CO ratio. On the contrary, the S/CO ratio and RIBA pattern remained unaltered in chronic hepatitis C with acute exacerbation. The rise in S/CO was usually accompanied with an increase in the number of RIBA reactive bands and their intensity in acute hepatitis C patients. The rise in S/CO ratios using a third generation anti‐HCV assay and the RIBA pattern might be used as a supplemental diagnostic criterion for acute HCV infection.
Since the identification and molecular characterization of the non-A, non-B hepatitis virus (HCV) in 1989, a variety of diagnostic tests based on the detection of hepatitis virus antibodies or HCV ...RNA in the serum have been developed and refined. The enzyme-linked immunosorbent assays (ELISAs) and the recombinant immunoblot assays (RIBAs) exhibit improved sensitivity and specificity for HCV antibodies compared with their predecessors, and the ELISA-3 is at the forefront of HCV screening. Furthermore, the advent of molecular assays that employ quantitative reverse-transcriptase polymerase chain reaction to detect HCV RNA has allowed clinicians to track the natural history of HCV and to monitor the progress of therapy. A role for further refinement of an HCV diagnosis using tests to determine genotype, subtype, and quasispecies is explored. In addition, the role of liver biopsy and non-invasive markers of histologic status are placed into the context of patient prognosis. This article reviews the state-of-the-art tests and assays developed for the diagnosis and management of HCV infection.
Background: The Bcl‐2 gene is a member of the rapidly expanding Bcl‐2 family of genes that regulate apoptosis. Bcl‐2 has been shown to repress cell death triggered by a diverse array of stimuli, ...including chemotherapy and gamma irradiation.
Objective: The purpose of this study was to determine feline Bcl‐2 expression level in feline lymphoma cells using an immunoblot assay with anti‐human and anti‐canine Bcl‐2 monoclonal antibodies.
Methods: About 708 base pairs containing the coding sequence of the feline Bcl‐2 gene were transformed into Escherichia coli. The recombinant Bcl‐2 was used as a positive control for an immunoblot assay using mouse monoclonal antibodies against human and canine Bcl‐2. An immunoblot assay using the monoclonal antibodies was carried out to determine the level of feline Bcl‐2 expression in lymphoma and lymphocytic leukemia cell lines.
Results: The recombinant feline Bcl‐2 protein produced in E. coli had a molecular weight of about 26 kDa and was detected by immunoblot assay by using anti‐human Bcl‐2 mouse monoclonal antibody. Feline Bcl‐2 expression was high in lymphoma cell lines (FL‐74‐UDC‐1 and FT‐1) and low in the cell line from peripheral blood mononuclear cells from a healthy cat (FeTJ‐1) but not low in freshly isolated peripheral blood mononuclear cells from a healthy cat. The anti‐human Bcl‐2 mouse monoclonal antibody was found to cross‐react with feline Bcl‐2.
Conclusions: These results confirm the expression of Bcl‐2 in T‐cell lymphoma cell lines and indicate that it is suitable to detect feline Bcl‐2 using an immunoblot assay. Pending further evaluation, Bcl‐2 expression might be useful in the differential diagnosis of feline tumors.
The diagnosis of neuroborreliosis (NB)—a serious complication of Lyme disease—relies on demonstration of intrathecal borrelia antibody production. We hypothesized that if a qualitative difference ...between the cerebrospinal fluid and the serum immunoblot-banding patterns was observed, then the borrelia antibodies found in the CSF could not be the result of leakage of serum antibodies to the CSF due to blood–brain barrier damage, but rather had to be produced intrathecally. CSF/serum pairs from 69 NB patients and from 85 control patients with other neurological disorders were investigated. All samples were tested blindly by immunoblot and a commercial capture ELISA kit for NB. The concordance between the two methods was 85.7%. When using the other method as reference, the accuracy of the two assays in the two patient materials was similar: 80% for sensitivity and 95% for specificity. Four types of comparative immunoblot-banding patterns that reflected intrathecal borrelia antibody synthesis were distinguished. The study showed that a simple comparison between the immunoblot pattern of serum and CSF samples allows for a reliable diagnosis of NB by demonstration of intrathecal antibody production. This is the first study to show that a qualitative difference of the antibody response between the immune response of serum and CSF is a rule. The findings also imply that partly different B-cell populations are responsible for the antibody production in the blood and in the central nervous system. In addition, our observation provides possible implications for other infectious diseases with CNS involvement.
Hepatitis A, B, and C Gilson, R; Brook, M G
Sexually transmitted infections,
12/2006, Letnik:
82, Številka:
suppl 4
Journal Article
Recenzirano
Odprti dostop
Screening of asymptomatic sexually transmitted diseases (STD) clinic attendees is recommended to ascertain their immune status only if they meet the criteria for hepatitis A vaccination (see National ...Guideline on Management of the Viral Hepatitides A, B and C), which includes homosexual men in regions where an outbreak of hepatitis A has been reported, injecting drug users, and patients with chronic hepatitis B or C or other causes of chronic liver disease (evidence level III). Screening of asymptomatic STD clinic attendees is recommended if they fall into one of the groups at increased risk which includes injecting drug users, recipients of blood/blood products, needlestick recipients, HIV positive people, and sexual partners of HCV positive people (evidence level II).
Recent accumulated evidence shows that dialysis patients are a high-risk group for hepatitis C virus (HCV) infection. Assessment of HCV genotype distribution among dialysis patients may be important ...because specific viral genotypes are associated with different clinical manifestations, disease progression, and response to antiviral therapy. However, polymerase chain reaction–based methods are cumbersome and unsuitable for analyzing large cohorts of dialysis patients with HCV. Instead, this information can be obtained by using a novel recombinant immunoblot assay (RIBA) recently developed for determining HCV serotype. The RIBA HCV serotyping strip immunoblot assay (SIA; Chiron Corporation, Emeryville, CA), is based on an immunoblot strip with five lanes of immobilized serotype-specific HCV peptides from the nonstructural (NS4) and core regions of the genomes of HCV types 1, 2, and 3. HCV serotype is deduced by determining the greatest intensity of reactivity to the NS4 serotype-specific HCV peptide band in relation to the internal control band (human immunoglobulin G) intensity on each strip. HCV core peptide reactivity is used only in the absence of NS4 reactivity. We compared RIBA HCV serotyping SIA with genotyping using sera from a large (n = 107) cohort of HCV-infected patients undergoing chronic hemodialysis (HD). We successfully serotyped 79 of 107 patients (74%) undergoing HD. We found a remarkable concordance (65 of 70 results; 93%) between RIBA HCV serotyping SIA and genotyping (line probe assay LiPA) techniques (Κ = 0.786) with sera from viremic patients infected with a known genotype. Only 5 of 70 patients (7%) had apparently discordant results. In a subset of patients (28 of 107 patients; 26%) not typed by RIBA HCV serotyping SIA, most (24 of 28 patients; 86%) were successfully genotyped by LiPA technology. It was possible to assess serotype reactivity in some patients (9 of 107 patients; 7%) who could not be genotyped. The distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. In conclusion, (1) we found good agreement between serotyping and genotyping methods in our large cohort of dialysis patients infected with HCV; (2) the impaired immunocompetence conferred by uremia may limit serotyping analysis in some HCV-infected patients undergoing HD; (3) RIBA HCV serotyping SIA may be useful in tracking transmission routes for HD patients who cleared the virus and have only anti-HCV antibody; and (4) the distribution of HCV serotypes was associated with the antibody response against HCV proteins and the patterns of reactivity by RIBA HCV 2.0 SIA. Assessment of HCV strains appears to be very useful in the routine clinical activity of nephrologists within HD units because consistent biological differences among HCV strains exist. RIBA serotyping SIA is a simple, inexpensive, and highly reproducible assay to obtain information about HCV types in the HD setting.
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