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D Dhumeaux

Publications and source records attributed to D Dhumeaux.

At least 37 records · Page 2Linked to original sources
PubMed2000

Standardization of hepatitis C virus RNA quantification.

It was recently recommended that hepatitis C virus (HCV) RNA quantification be used to tailor the duration of combined interferon alfa (IFN-alpha)/ribavirin therapy in patients infected by HCV genotypes 1, 4, and 5. This recommendation has been difficult to implement in the absence of standardized quantitative units for HCV RNA. The aim of this work was to define clinically relevant HCV RNA loads in standardized international units (IU), for use in routine clinical and research applications based on standardized quantitative assays. Two hepatitis C virus RNA quantitative assays were used: (1) the Superquant assay (National Genetics Institute, Los Angeles, CA), for which possibly relevant thresholds were established; and (2) the semi-automated Cobas Amplicor HCV Monitor assay version 2.0 (Cobas v2.0, Roche Molecular Systems, Pleasanton, CA) that measures HCV RNA loads in IU/mL. Quantification in the Cobas v2.0 assay was linear over the entire range of values tested, including viral loads higher than 850,000 IU/mL after 100-fold dilution. The accuracy and precision of the measures in IU/mL were satisfactory with Cobas v2.0. The results obtained with Superquant and Cobas v2.0 correlated (r =.932; P <.0001). A value of 2,000,000 copies/mL (6.3 log(10) copies/mL) with Superquant was converted to nearly 800,000 IU/mL (5.9 log(10) IU/mL). In conclusion, all HCV RNA quantitative assays should give HCV RNA loads in international units and be validated with appropriate calibrated panels; 800,000 IU/mL in any of these assays should be used as the decision threshold to tailor the IFN-alpha/ribavirin treatment duration in patients infected by HCV genotypes 1, 4, and 5.

Antiviral Agents↗
PubMed2000

[Iron overload and liver diseases (except for hemochromatosis and dysmetabolic hepatosiderosis].

Iron accumulation in the liver is frequently observed in hepatic diseases whatever their etiologies. In the majority of cases, there is no true overload, and iron accumulation corresponds to deposits in macrophages secondary to iron release from damaged hepatocytes. More rarely, namely in severe cirrhosis, there is a true overload, which is probably related to iron intestinal hyperabsorption. In such case, the site of iron excess is hepatocytic. Except for hemochromatosis, mutations of HFE gene do not play a major role in iron overload. In chronic liver diseases, iron overload could favor the development of hepatocellular carcinoma, even in the absence of cirrhosis.

Hepatitis, Viral, Human↗
PubMed2000

[Strategies of hepatitis C screening in general practice. Results of a two-center randomized trial].

OBJECTIVES: To improve the detection of patients infected with hepatitis C virus. METHODS: A study was undertaken in the general medicine setting in two hepatitis C networks. General practitioners volunteered and received training on hepatitis C, then were randomly assigned to one of two screening strategies: group 1: general practitioners prescribed hepatitis C virus testing if the risk factors for HCV hepatitis C virus infection were identified during questioning of patients, group 2: general practitioners were helped in their screening approach by posters and leaflets on the risk factors of hepatitis C virus, available in the waiting room. RESULTS: A total of 184 general practitioners enrolled 90 from group 1 and 94 from group 2. During a 15-month-period, 617 serologies were prescribed, 323 by general practitioners in group 1 (in patients who were an average of 40 year-old) and 294 in group 2 (in patients who were an average of 44 year-old); 489 serologies (79.3%) were actually performed (261 and 228 respectively) and 25 (5.1%) tested positive (15 and 10 respectively). The number of prescribed, performed, and positive serologies did not differ from one group to the other. The motive for hepatitis C virus screening was similar in both groups and included a history of transfusion in 27% of cases, intravenous drug use in 6%, increased ALT or symptoms compatible with hepatitis in 13%, nosocomial exposure in 22%. Risk factors in the 25 patients who were hepatitis C virus positive were drug use (44%), history of transfusion before 1991 (16%), elevated ALT or symptoms (12%), others (28%). CONCLUSION: This study comparing screening strategies in general medicine, resulted in the diagnosis of hepatitis C virus infection in 5% of tested patients, regardless of the strategy. However, the fewer serologies prescribed by general practitioners (an average of 3 tests in a 15-month-period) suggests a low rate of identified risk factors in general practice, and emphasizes that other types of screening procedures should be implemented and evaluated.

Adolescent↗
PubMed1999

[The G virus: the orphan virus].

The GB-C/hepatitis G virus (GBV-C/HGV) was discovered in 1995. Its prevalence in the general population of industrialized countries is relatively high. The GBV-C/HGV virus is transmitted by blood and blood-product transfusion, intravenous drug abuse, sexual transmission and mother-fetus transmission. To date, this virus has not been associated with acute or chronic hepatitis and as such hepatitis G virus is a misnomer. This orphelin virus is thus still looking for the right name and perhaps an induced pathology.

Blood Transfusion↗
PubMed1999

Inhibitor against coagulation factor V after liver transplantation.

A new case of anti-factor V inhibitor is described in a 46-year-old man, who received a liver transplantation for hepatocellular carcinoma, without exposure to bovine thrombin or fibrin glue during the operative course. The inhibition occurred on the 14th postoperative day, while the patient was being treated with oxacillin, azathioprine, and a new immunosuppressive drug, FK506. The inhibition was of short duration (3 days), and no bleeding complication occurred despite a very low plasmatic level of factor V activity and antigen (<5%). Plasma samples drawn after cessation of FK506 disclosed a dose-dependent inhibitory activity when alcoholic solutions of FK506 were exogeneously added; this suggests a possible role of the FK506 drug in the occurrence of this anti-factor V inhibitor.

Carcinoma, Hepatocellular↗
PubMed1999

Increased incidence of oropharyngeal squamous cell carcinomas after liver transplantation for alcoholic cirrhosis.

BACKGROUND: THE aim of this study was to describe the features of posttransplantation tumors observed in a series of liver transplant recipients with special reference to patients receiving a transplant for alcoholic cirrhosis. METHODS: Among 171 consecutive liver transplant recipients, 90 patients who had received a first liver allograft for cirrhosis were studied. After liver transplantation, detection of de novo malignancies was prospectively undertaken and the characteristics of the patients in whom tumors occurred were compared with those in whom tumors did not develop. RESULTS: With a follow-up of 45.2+/-21.2 months, 11 tumors were observed in 90 patients (overall incidence of 12.2%). The incidence of tumors was higher in patients receiving a transplant for alcoholic cirrhosis than in patients receiving a transplant for nonalcoholic cirrhosis (26.7% vs. 5.0%, P<0.01). Squamous cell carcinoma (SCC) of the oropharynx or esophagus and posttransplant lymphoproliferative disorders were mainly observed. SCC (uvula in two cases, tongue in one case, esophagus in one case, pharynx in one case) occurred exclusively in patients transplanted for alcoholic cirrhosis (16.7% vs. 0%, P=0.001). The incidence of posttransplant lymphoproliferative disorders was similar in alcoholics and nonalcoholics (6.7% vs. 5%, NS). Survival was not influenced by the occurrence of SCC. CONCLUSION: The incidence of oropharyngeal SCC could be high in patients receiving a transplant for alcoholic cirrhosis. This could be due to an additional effect of posttransplantation immunosuppression in patients exposed to alcohol and tobacco before transplant. Careful posttransplantation screening of oropharyngeal SCC is warranted after liver transplantation for alcoholic cirrhosis.

Carcinoma, Squamous Cell↗
PubMed1999

Role of hepatitis C virus in lymphoproliferative disorders after liver transplantation.

It has been suggested that hepatitis C virus (HCV) infection could be associated with B-cell clonal expansion. The aim of this study was to analyze the relationship between lymphoproliferative disorders and HCV infection in liver transplant recipients. We studied 157 patients receiving a liver transplant between January 1989 and May 1997 with a follow-up longer than 3 months. The incidence of posttransplant lymphoproliferative disorders (PTLDs) was analyzed with reference to the indication for liver transplantation, the induction and maintenance immunosuppression, the incidence of acute rejection episodes, and Epstein-Barr virus (EBV) infection. Six PTLDs occurred after a median posttransplant follow-up of 7 months (3.8%). Four of the 6 PTLDs occurred among the 38 patients transplanted for HCV-related cirrhosis, and 2 PTLDs occurred in the 119 patients receiving a liver transplant for non-HCV liver diseases (10.5% vs. 1.7%, respectively; P =.03). The 4-year probability of PTLD was significantly higher in patients receiving a liver transplant for HCV-related cirrhosis than non-HCV liver diseases (12.3% vs. 2.2%, respectively; P =.015). Patients receiving a liver transplant for HCV-related cirrhosis were more likely to receive antithymocyte globulins (ATG). However, in patients treated with ATG, the 4-year probability of PTLD was higher among those patients receiving a liver transplant for HCV-related cirrhosis than for non-HCV liver diseases (27.1% vs. 6.4%, respectively; P =.08). EBV gene products were detected in tumor tissues in 3 of 4 patients with HCV-associated PTLD. Our data suggest that, in addition to EBV infection, 2 mutually nonexclusive factors, i.e., the use of ATG and HCV infection, could play a role in the occurrence of PTLD after a liver transplant for HCV-related cirrhosis.

Adult↗
PubMed1999

Quantification of hepatitis C virus RNA in serum by branched DNA-based signal amplification assays.

The objective of the study was to compare the clinical sensitivity and specificity of versions 1.0 and 2.0 of the branched DNA (bDNA)-based hepatitis C virus (HCV) RNA quantification assay, and also to compare the values yielded by the two versions according to the HCV genotype. Serum samples from 268 patients tested routinely by a non-quantitative HCV RNA PCR assay (group A) were tested with version 2.0 of the bDNA assay. Samples from 342 HCV PCR-positive patients with chronic hepatitis C eligible for interferon treatment (group B) were tested with both version 1.0 and version 2.0 of the bDNA assay. Version 2.0 had a clinical sensitivity of 92% (95% confidence interval (CI): 87-97%) in group A and 89% (86-92%) in group B. In group B, the gain in sensitivity with bDNA 2.0 was 16% relative to bDNA 1.0 (P < 0.001). The log values of the two assays correlated with samples positive by both assays (r = 0.83, P < 0.0001), but the distribution of values was larger in samples containing HCV genotypes 2 and 3. The mean ratio of assay 2.0/assay 1.0 values was 1.69 +/- 1.44 (range: 0.33-13.43). The mean ratio was close to 1 with samples containing genotype 1 or 4, but ranged from 0.33 to more than 5. The mean ratio was close to 3 with samples containing genotype 2 or 3, and ranged from 0.5 to more than 13. HCV RNA levels were significantly lower in samples containing genotype 4 than in those containing other genotypes. Sera from 200 anti-HCV-negative, HCV RNA PCR-negative blood donors (group C), and from 164 anti-HCV-negative patients with symptoms of chronic liver disease (group D) were used to assess the clinical specificity of bDNA 2.0. In addition, samples with an HCV RNA titer between 0.2 (assay cutoff) and 0.5 MEq/ml from a group of 546 patients tested routinely for HCV RNA load by bDNA 2.0 (group E) were retested by bDNA 2.0 and by qualitative PCR. The specificity of bDNA 2.0 was 100% (98-100%) in group C and 99% (97-100%) in group D. Among the 41 samples from group E, 38 were positive by bDNA 2.0 retesting (36 were PCR-positive) and three were negative by bDNA 2.0 retesting (all were PCR-positive). It is concluded that version 2.0 of the bDNA assay is markedly more sensitive than version 1.0 and has a good specificity. In contrast with version 1.0, version 2.0 is not influenced by the HCV genotype. The relationship between values obtained with assays 1.0 and 2.0 on clinical specimens is not linear, indicating that HCV RNA titers cannot reliably be calculated from the results of version 1.0.

DNA, Viral↗
PubMed1999

Liver iron accumulation in patients with chronic active hepatitis C: prevalence and role of hemochromatosis gene mutations and relationship with hepatic histological lesions.

BACKGROUND/AIMS: Liver iron accumulation has been described in patients with chronic active hepatitis (CAH) C, and could play a role in the course of liver disease and negatively influence the response to interferon. The aim of this study was to determine the prevalence and severity of liver iron accumulation in CAH C, to assess its relationship with the HFE C282Y and H63D mutations, and to study its interactions with hepatic histological lesions. METHODS: Two hundred and nine patients (131 men, 78 women, mean age 44.3+/-12.0 years) with CAH C, including 19 patients with cirrhosis (9.1%) were studied. A semiquantitative grading system from 0 to 3 was used for histological assessment of liver iron accumulation on Perls' staining. The HFE C282Y and H63D mutations were screened for by restriction enzyme analysis performed on PCR-amplified products. Histological scores of activity and fibrosis were determined according to a previously validated METAVIR score system. RESULTS: Liver iron accumulation was found in 88/209 patients (42.1%), and was generally mild. The C282Y and H63D allele frequencies were in 23 (11.0%), and 50 (23.9%), respectively. No association was found between the presence of liver iron accumulation and the detection of the C282Y and H63D mutations. A significant relationship was found between the severity of histological activity and liver iron accumulation of macrophagic or mixed (i.e. both macrophagic and hepatocytic) type (p = 0.04). Although the number of cirrhotic patients was small, cirrhosis was more frequently observed in patients with than without liver iron accumulation (17.2% vs. 3.3%, p = 0.004). CONCLUSIONS: Overall, these data suggest that the liver iron accumulation in patients with CAH C is significantly associated with histological activity and cirrhosis, whereas the two missense hemochromatosis gene mutations are not major determinants.

Adult↗
PubMed1999

Low HCV replication levels in end-stage hepatitis C virus-related liver disease.

BACKGROUND/AIMS: The relationship between HCV RNA levels and the severity of HCV-related liver disease has been addressed in a few studies, which has led to conflicting results. To clarify this point, we studied serum HCV RNA levels in patients with HCV liver disease at various stages, using a second-generation branched DNA (bDNA) assay. METHODS: One hundred and forty-eight patients with chronic HCV infection were classified into 3 groups: group A included 92 patients with chronic active hepatitis (CAH) without cirrhosis; group B included 30 patients with CAH and compensated cirrhosis; group C included 26 patients with end-stage cirrhosis. In all patients, serum HCV RNA was sought by qualitative PCR and quantified using second-generation bDNA assay. HCV RNA was also quantified after liver transplantation in 22 patients from group C. HCV genotype was determined in all patients. RESULTS: HCV RNA was detected by PCR in 100%, l00% and 92% of the patients from groups A, B and C, respectively (NS). The proportion of patients with HCV RNA levels higher than the cut-off of bDNA assay was significantly lower in patients from group C than in patients from groups A and B (50% vs 94% and 93% respectively, p<0.0001). The mean HCV viremia was lower in group C than in groups A and B (1.35+/-0.24 MEq/ml vs 5.00+/-6.04 MEq/ml and 5.85+/-7.70 MEq/ml, respectively, p<0.0001). This difference was independent of HCV genotype. In the patients from group C, post-transplant HCV RNA levels were significantly higher than pretransplant HCV RNA levels (14.90+/-26.40 vs 1.35+/-0.24 MEq/ml, p=0.0065). CONCLUSIONS: HCV RNA levels do not appear to differ significantly among patients with CAH with or without compensated cirrhosis. In contrast, HCV RNA levels seem to be significantly lower in patients with end-stage HCV-related liver cirrhosis. In these patients, high levels of replication are restored after liver transplantation, suggesting that low pretransplant viral loads are not due to the intrinsic characteristics of the infective viral strains, but rather to the severity of liver disease.

Adult↗
PubMed1999

Evolution of the hepatitis C virus second envelope protein hypervariable region in chronically infected patients receiving alpha interferon therapy.

Sustained hepatitis C virus (HCV) RNA clearance is achieved in 8 to 12% of patients with chronic HCV infection treated with alpha interferon (IFN-alpha) at the approved dose of 3 MU three times a week for 6 months and in about 25% of those receiving this treatment for 12 months. We used single-strand conformation polymorphism analysis combined with cloning and sequencing strategies to characterize the genetic evolution of HCV second envelope gene hypervariable region 1 (HVR1) quasispecies during and after IFN therapy in patients who failed to clear HCV RNA. Sustained HCV RNA clearance was achieved in 6% of patients. Profound changes in HVR1 quasispecies major variants were estimated to occur in 70% of the patients during and after therapy. These changes were evolutionary and were characterized by shifts in the virus population, related to selection and subsequent diversification of minor pretreatment variants. The quasispecies changes appeared to be induced by changes in the host environment likely resulting from the IFN-induced enhancement and post-IFN attenuation of neutralizing and possibly cytotoxic responses against HVR1. The remaining patients had no apparent changes in HVR1 quasispecies major variants, suggesting selection of major pretreatment variants, but some changes were observed in other genomic regions. We conclude that IFN-alpha administration and withdrawal profoundly alters the nature of circulating HCV quasispecies, owing to profound changes in virus-host interactions, in patients in whom sustained HCV RNA clearance fails to occur. These changes are associated with profound alterations of the natural outcome of HCV-related liver disease, raising the hypothesis of a causal relationship.

Adolescent↗
PubMed1999

[Prevalence of hepatitis C virus infection in pregnant woman on the island of Réunion].

AIMS: The aim of this prospective study was to assess the prevalence of anti-hepatitis C virus antibodies in a population of pregnant women in Réunion. METHODS: Over a 6-month period, all blood samples of pregnant women who delivered at a hospital in the south of Réunion were tested with a third generation enzyme-linked immunoassay. In addition, risk factors for hepatitis C transmission were systematically looked for. RESULTS: Among the 1,455 women tested during this period, only 2 sera were found to be positive, resulting in a prevalence of 0.14%. One of these women had a history of intravenous drug use, whereas the other had no identified risk factor. This low prevalence was found to be associated with a low frequency of risk factors of C virus infection in this population: a history of transfusion and intravenous drug use was found in 2.9% and 0.21% of cases, respectively. CONCLUSIONS: The prevalence of hepatitis C virus infection is particularly low in Réunion. This low prevalence is explained by the rarity of risk factors for hepatitis C transmission in this region which is close to the African continent and has a similar high prevalence of hepatitis B virus infection.

Female↗