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Biomedical subjects

A M Courouce

Publications and source records attributed to A M Courouce.

At least 19 recordsLinked to original sources
PubMed2001

Blood donors infected with the hepatitis B virus but persistently lacking antibodies to the hepatitis B core antigen.

BACKGROUND AND OBJECTIVES: Antibodies to the core of hepatitis B virus (anti-HBc) are considered to be the best serologically reliable markers of hepatitis B virus (HBV) infection. Through a national epidemiological survey, two young and first-time blood donors, originating from HBV-endemic areas, were identified as HBV carriers with an absence of anti-HBc reactivity. MATERIALS AND METHODS: We followed up these two subjects in order to investigate the evolution of their HBV serological profiles. Nucleotide sequencing was performed of the entire pre-C/C region of the strains infecting these donors. RESULTS: The same serological profile of active viral replication with an apparent persistent lack of anti-HBc and normal alanine aminotransferase (ALT) levels was found for both subjects throughout a follow-up of 19 months and 4 months, respectively. Neither donor was immunocompromised. Nucleotide sequence analysis of the pre-C/C region did not show mutations or deletions in encoded proteins. CONCLUSION: The hypothesis of an in utero HBV infection responsible for an immune tolerance to HBV seems to be the most probable explanation for this particular immunological situation. Such occurrences in the blood donor population are probably rare as less than 0.1% of hepatitis B surface antigen (HBsAg)-positive donors exhibit such a profile, in our experience. Moreover, this phenomenon does not impose a risk of HBV transmission by blood donation, as the exclusion of HBV-infected blood donation is based on HBsAg detection. However, such a risk might be encountered with the hepatitis C virus (HCV) for which at present only antibodies to HCV are screened.

Adult↗
PubMed2000

HCV RNA in blood donors with isolated reactivities by third-generation RIBA.

BACKGROUND: The objective of this collaborative study was to learn the proportion of HCV RNA-positive samples obtained from a population of donors with isolated anti-HCV reactivities by third-generation RIBA (RIBA-3) (indeterminate results). STUDY DESIGN AND METHODS: During a 2-year period, 11 blood transfusion centers kept all samples with indeterminate RIBA-3 results to test them by PCR, using both local and commercial techniques. RESULTS: Of the 758 RIBA-3 indeterminate samples, 10 (1.3%) were positive for HCV RNA: 3. 3 percent (6/180) and 1.3 percent (4/317) of samples with anti-core or anti-NS3 reactivity, respectively, and none of the 52 and 209 samples with anti-NS4 or anti-NS5 reactivity, respectively. HCV RNA-positive donors with anti-core reactivity were infected with different subtypes (1 with HCV subtype 1b, 1 with 2, 1 with 2a/2c, 2 with 3a, and 1 with 5a), and a follow-up indicated a chronic-carrier state in two of the six donors. Acute hepatitis was diagnosed in three of the four donors with anti-NS3 reactivity alone. Two of these three were IV drug users and were infected with subtype 1a. CONCLUSION: HCV RNA-positive donors with indeterminate results in RIBA-3 are extremely rare, but they do exist. They were observed only when either anti-core or anti-NS3 was present. With such a RIBA-3 profile, PCR testing remains necessary to reveal an eventual acute or chronic HCV infection.

Adolescent↗
PubMed1997

Increasing diversity of HIV-1M serotypes in French blood donors over a 10-year period (1985-1995). Retrovirus Study Group of the French Society of Blood Transfusion.

OBJECTIVE: Phylogenetic analysis of gene sequences of HIV-1 has led to the classification of isolates into a major group (M) of viruses, itself divided into subtypes (A to I), and a minor group (O) of rare isolates. Subtype B viruses are the most prevalent in Western countries but little is known about the dynamics of diffusion of the other subtypes in these regions. The prevalence of B subtypes and non-B subtypes in French blood donors between 1985 and 1995 was evaluated. METHODS: A retrospective study was conducted in 490 blood donors, identified as positive for antibody to HIV-1, by twelve French blood banks between 1985 and 1995. Serological subtyping was performed with a subtype-specific enzyme immunoassay, the reliability for genotyping of which has been demonstrated previously. RESULTS: Of 450 typable samples, 48 (10.7%) were non-B subtypes. Non-B reactive samples were found in all of the regions. An increasing prevalence of individuals infected by non-B viruses was observed, from approximately 4% in the early period to more than 20% in 1994-1995 (P = 0.0004). Non-B viruses did not appear to be restricted to patients with direct or indirect epidemiological links to non-European populations. CONCLUSION: We observed an increasing diversity of HIV-1 strains in the population of blood donors residing in France. This stresses the necessity to broaden the surveillance of HIV-1 diversity in order to improve measures to prevent HIV-1 infections.

Adult↗
PubMed1995

Genotype distribution and transmission of hepatitis C virus (HCV) in French haemodialysed patients.

BACKGROUND: HCV genotyping was performed to identify the source of HCV infection in haemodialysed patients. METHODS: Specimens from 48 HCV-infected patients treated in the same dialysis unit were genotyped by line probe assay (LiPA). RESULTS: Thirty-seven patients (77%) were infected by genotype 1b. Only four of the 48 patients were never transfused and three of them had genotype 1b. In two of the three genotype 1b-infected patients, seroconversion was observed during the follow-up , suggesting a nosocomial HCV infection. Ten of the 44 transfused patients were infected with genotypes other than 1b. Blood products were very probably the source of infection in these patients. The 34 other patients (77.3%) were infected with genotype 1b and retrospective analysis failed to identify nosocomial and transfusional origin. Eight of the 11 patients with genotypes different from 1b were found in the 16 patients who were more than 55 years old. Only three of the eight originated from France. CONCLUSION: Blood transfusions and nosocomial infections were the main causes of HCV transmission in haemodialysed patients. Both screening of blood donors and aseptic measures in haemodialysis units may prevent HCV transmission.

Adult↗
PubMed1994

Randomised placebo-controlled trial of recombinant interleukin-2 in chronic uraemic patients who are non-responders to hepatitis B vaccine.

Natural interleukin-2 at low dose has been reported to overcome the non-responsiveness of patients with chronic uraemia to hepatitis B vaccine. Therefore, we revaccinated 52 previous such non-responders (24 on maintenance dialysis) with 20 micrograms of recombinant preS2-containing hepatitis B vaccine with human recombinant interleukin-2 (1 MU) or placebo (randomly allocated). Seroconversion rates (74 vs 80%, respectively) and proportion of patients who elicited anti-HBs titres of 10 mlU/mL or more (56 vs 68%) were similar in both groups. Our results do not confirm local injection of interleukin-2 as an effective immunoadjuvant to hepatitis B vaccine in uraemic patients.

Adjuvants, Immunologic↗
PubMed1993

Assessment of screening tests for transfusion-associated non-A non-B hepatitis.

Non-A non-B hepatitis is the most common serious sequela of blood transfusion, and its screening has become an essential goal of blood transfusion centers. Before 1989, two surrogate screening tests (for alanine aminotransferase and for antibody to hepatitis B core antigen) were used; in 1989, a direct test for the antibody to hepatitis C virus (the main agent of this hepatitis) was developed. The French National Agency for the Development of Medical Evaluation undertook an investigation to determine the optimal prevention strategy for posttransfusion non-A and non-B hepatitis (PTH). A detailed literature review was performed, complemented by expert group opinion. The performance of each test was derived indirectly by calculating the number of cases of PTH averted by each test. Hepatitis C virus testing is probably the most promising strategy, but different policies can be developed given the uncertainties of scientific data. Cost considerations should be taken into account in identifying the best screening strategy.

Alanine Transaminase↗
PubMed1993

Secondary immune response to hepatitis B virus vaccine in alcoholics.

The efficacy of full vaccination against hepatitis B virus (i.e., including the 1-year booster injection) was evaluated in 28 alcoholic patients with minimal liver disease. Although such patients are reportedly poor responders, the proportion of those protected (anti-HBs titer > = 10 mlU/ml) rose from 42.8% after primary immunization to 82% after the booster. The mean anti-HBs titer, which remained low in the overall group, was significantly lower in the subjects who resumed drinking during the follow-up period than in those who did not. This suggests a direct influence of alcohol itself on the response, because none of our patients had cirrhosis and none were clearly malnourished. Among the 17 patients for whom the 2-year post-booster anti-HBs titer could be determined, all those with a 1-month postbooster titer above 1000 mlU/ml still had a high anti-HBs level (> 100), whereas 80% of those with a 1-month postbooster titer < 1000 had 2 years later only a low (< 100) or even an unprotective anti-HBs level; this means that only the latter should be considered for a new booster injection. Our data indicate that protection against hepatitis B virus can be achieved in a good proportion of alcoholics with a full vaccination protocol. We suggest that efficacy should be evaluated 1 month after the booster, and that patients with low postbooster anti-HBs titers should be tested at regular intervals, because they can also be protected provided an adapted schedule of further injections is conducted.

Adult↗
PubMed1993

Antibodies to hepatitis C virus by second generation test in hemodialyzed patients.

To assess the prevalence and the incidence of hepatitis C virus (HCV) in a dialysis unit, we prospectively tested for anti-HCV in chronic hemodialysis patients and staff members since January 1989, using a first generation assay. Incidence was nil in staff and low in patients (3.7% in 89, 1% in 90), and prevalence was 30% in patients. In January 1991 blood samples from 115 patients were tested by first (EL1) and second generation (EL2) ELISA (Ortho Diagnostic System). Positive subjects were tested by a RIBA-2 confirmation test. Fifty-three patients were negative by all tests. Positive tests were observed in 62 patients (54%) including 36 positive in EL1 and EL2, and 26 only by EL2. All positive patients were reactive by RIBA-2 but nine were classified undetermined (only one positive band). In five patients reactivity of antibodies to 5-1-1 and C-100-3 gradually declined during the study. Second generation tests gave a better correlation with time on dialysis and blood transfusion. We conclude that second generation tests for HCV are more accurate for estimating true prevalence of HCV infection in hemodialysis units.

Adolescent↗
PubMed1992

Fibrin ring granulomas in hepatitis A.

Fibrin ring granuloma is characterized by a fibrinous ring surrounding a central fat vacuole. It has been found in the liver and bone marrow of patients with Q fever, and occasionally with visceral leishmaniasis, cytomegalovirus, Epstein-Barr virus, Staphylococcus epidermidis infections, Hodgkin's lymphoma, and hypersensitivity to allopurinol. We describe a case of serologically confirmed viral hepatitis A with this lesion in the liver biopsy. A false positive anti-hepatitis A virus IgM result has been excluded. This is, to our knowledge, the second reported case of type A hepatitis with hepatic fibrin ring granulomas. It confirms that hepatitis A should be included in the differential diagnosis of this lesion.

Acute Disease↗
PubMed1992

Passive immunotherapy in AIDS: a randomized trial of serial human immunodeficiency virus-positive transfusions of plasma rich in p24 antibodies versus transfusions of seronegative plasma.

To assess the place of passive immunotherapy in the treatment of AIDS, a randomized study was conducted that evaluated the safety and short-term efficacy of serial transfusions of human immunodeficiency virus type 1 (HIV-1) seropositive plasma in 18 patients. Heat-inactivated anti-HIV antibody-rich plasma was compared with seronegative fresh-frozen seronegative plasma given in addition to zidovudine and other conventional prophylactic treatments. Seven transfusions every 2 weeks of immune plasma significantly reduced (2 vs. 8, P = .016) the number of opportunistic infections. Antigenemia became undetectable. When transfusions were stopped, positive p24 antigenemia returned at a level higher than before treatment and was correlated with a severe clinical deterioration, suggesting a rebound effect. This trial suggests that passive immunotherapy is promising in AIDS treatment. It confirms also that plasma donation does not affect donors' CD4 cell count over a 1-year period. In patients with severe immunodeficiency, special attention should be paid to withdrawal of an effective therapy as virologic relapse may be explosive and poorly tolerated.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Human T lymphotropic virus (HTLV) type I and II DNA amplification in HTLV-I/II-seropositive blood donors of the French West Indies.

To confirm the presence of DNA from human T lymphotropic virus type I (HTLV-I), HTLV-II, or both in individuals found HTLV-I/II-positive through systematic screening of blood donations in Guadeloupe (French West Indies), 42 blood donors repeatedly positive for HTLV-I/II by ELISA were studied by polymerase chain reaction (PCR). Three primer pairs (env, pol, tax) targeted on conserved regions of HTLV-I or -II sequences (or both) and six probes (two generic, two HTLV-I-specific, two HTLV-II-specific) were used in a multiplex PCR. HTLV-I sequences were detected in 31 individuals (74%). All 31 subjects positive by Western blot (WB) harbored HTLV-I sequences. Fifteen individuals (48%) were positive with the three primer pairs used, 10 (32%) with two, and 6 (20%) with one. Subjects indeterminate or negative by WB were all negative by PCR. No HTLV-II sequences were detected with specific probes. The results indicate the absence of HTLV-I and -II infection in individuals with indeterminate WB, the presence of HTLV-I DNA in individuals positive for WB in the French West Indies, and the absence of HTLV-II infection in the cohort.

Adult↗
PubMed1991

[Efficacy in viral inactivation of the concentrates of factor VIII and IX by the solvent/detergent procedure. Evaluation in patients with hemophilia].

Human immunodeficiency virus (HIV) infection and hepatitis virus B or C (HBV, HCV) transmission are major risks following infusion of coagulation factor concentrates. Thus, several methods have been used to achieve viral inactivation of concentrates prepared from plasma collected from a large number of donors. In this study, 32 patients with haemophilia A or B (n = 31) or von Willebrand's disease (n = 1) were treated between 1987 and 1990 only with factor VIII or IX concentrates inactivated by the solvent-detergent procedure. During this period, none of these cases exhibited elevated liver enzymes (alanine amino transferase), and serological tests for HIV, HBV and HCV infections always remained negative. This suggests that the solvent-detergent procedure of concentrate inactivation is an efficient method to prevent not only HIV or HBV transmission but also HCV infection in haemophiliacs.

Adolescent↗