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Philippe Halfon

Publications and source records attributed to Philippe Halfon.

At least 19 recordsLinked to original sources
PubMed2025

Fatal Hepatitis B Reactivation in Absence of Antibody to Hepatitis B Core Antigen in a Lymphoma Patient.

Reactivations of hepatitis B virus (HBV) infection in severely immunocompromised patients with serological profiles of past hepatitis B are non-exceptional and potentially severe or fatal events. The preventive and pre-emptive detection of this serological status is compromised in the absence of antibodies to hepatitis B core antigen (anti-HBc), observed in a very small number of cases of HBV infection. Here, we describe the case of a patient with a serological profile indicating a HBV vaccination although the patient did not report previous vaccination, following lymphoma and chemotherapy including rituximab. This patient presented HBV reactivation with appearance of hepatitis B surface antigen (HBsAg) but without appearance of anti-HBc, suggesting the absence of detectable anti-HBc in this patient at the stage of past infection. Next-generation sequencing provided the complete HBV genome, showing the presence of a mutation in HBsAg associated with immune escape but without the detection of mutations in the core gene previously described as significantly associated with the absence of anti-HBc. Nonetheless, W28* pre-core mutation was found, which was reported to enhance replication capacity in case of weak immune responses and suspected to promote HBV reactivation in association with immune escape mutations. Overall, this case highlights that negativity of anti-HBc cannot definitely rule out past HBV infection and the risk of HBV reactivation in immunocompromised patients in the context of treatment of hemopathies, and that it is difficult to assess such a risk and to prevent or monitor HBV reactivation in patients with past HBV infection but no detectable anti-HBc.

Female↗
PubMed2006

Prospective evaluation of the Hybrid Capture 2 and AMPLICOR human papillomavirus (HPV) tests for detection of 13 high-risk HPV genotypes in atypical squamous cells of uncertain significance.

The use of high-risk human papillomavirus (hrHPV) testing as an adjunct to cervical cytology in population-based screening programs is currently based on DNA hybridization and PCR assays. The aim of this study was to prospectively assess the diagnostic performance of the Hybrid Capture 2 test (HC2; Digene Corporation) in comparison with that of the recently developed PCR-based AMPLICOR HPV test (Roche Molecular Systems) for the detection of 13 hrHPV types. A reverse line blot hybridization assay (Innogenetics) was used as an internal reference standard in discordant cases. Two hundred seventy-one patients with atypical squamous cells of uncertain significance (ASCUS) in cervical samples underwent hrHPV testing. The chi-square test was performed to compare respective proportions. Totals of 160/271 (59%) and 156/271 (58%) were found to be positive for hrHPV with HC2 and AMPLICOR, respectively. Concordant results were obtained for 235 (86.7%) of the 271 samples (kappa statistic, 0.73 +/- 0.04). Considering types 26, 53, and 66 as oncogenic types, negative predictive values (NPVs) of HC2 and AMPLICOR were 92.8% and 87.8%, respectively (difference was not significant), and their respective accuracies were 94.8% and 91.9% (difference was not significant). Considering types 26, 53, and 66 as not oncogenic, the respective HC2 and AMPLICOR NPVs were 92.8% and 97.4% (difference was not significant), and accuracy was significantly higher for the AMPLICOR assay (95.9% versus 90.8% for HC2) (P<0.05). For ASCUS samples, the NPV was 92.8% for HC2 testing and might be compromised if the copy number of HPV DNA was low. The NPV was 97.4% for the AMPLICOR assay and might be compromised if HPV types 26, 53, and 66 were considered oncogenic. The accuracy of these two assays is good and is compatible with routine clinical use in the triage of ASCUS cases.

Carcinoma, Squamous Cell↗
PubMed2006

Comparison of test performance profile for blood tests of liver fibrosis in chronic hepatitis C.

BACKGROUND/AIMS: We evaluated the test performance profile (TPP) of blood tests of liver fibrosis. METHODS: Three hundred and fifty-six patients with C chronic hepatitis were included in two centers. Metavir staging of liver specimens by two independent pathologists and the following tests were evaluated: Fibrotest (FT), APRI, FibroMeter (FM), and Hepascore (HS). RESULTS: Metavir stages were: F0: 4%, F1: 55%, F2: 26%, F3: 11%, and F4: 4%. The AUROCs were not significantly different, respectively, FT, FM, APRI, HS: >or=F2: 0.79, 0.78, 0.76, >or=0.76; F3: 0.81, 0.85, 0.81, 0.81; and F4: 0.86, 0.94, 0.92, 0.89. The TPP relies on the paired comparison of blood-test misclassification based on liver specimen, e.g. FT vs FM, respectively: F0+1: 18 vs 28% (p=0.0003), >or=F2: 43 vs 31% (p=0.004). There was no center effect. CONCLUSIONS: In those populations, the four blood tests had a similar performance for significant fibrosis (F>or=2), lying in the lower range of published results which is attributable to a low >or=F2 prevalence, and for >or=F3 and F4. However, FM and FT had performance profiles significantly different as a function of fibrosis stages or diagnostic target (fibrosis cut-off). This has to be considered during the interpretation process. Moreover, the performance should be reported with different diagnostic targets.

Adult↗
PubMed2006

Medically assisted procreation and transmission of hepatitis C virus: absence of HCV RNA in purified sperm fraction in HIV co-infected patients.

OBJECTIVE: The risk of hepatitis C virus (HCV) transmission in medically assisted procreation (MAP) is debated and some researchers have proposed to exclude MAP for HCV-positive infertile patients. The objectives of this study were to assess the presence of viral RNA in the final preparation of density gradient semen fractions collected from men with chronic HCV and HIV co-infection participating in a MAP program, and to assess whether HIV co-infection influences the rate of the presence of HCV RNA in the semen. DESIGN AND METHODS: The study was based on a cohort of 170 HCV-infected male patients (93 HIV co-infected) participating in a MAP program in a French center. Semen samples were subjected to standard MAP sperm preparation, using density-gradient centrifugation with 40 and 90% layers. All aliquots were tested with a commercially available HCV RNA assay (Roche Monitor), adapted for use with semen after a nucleic HCV RNA extraction modification (Organon Technika). RESULTS: Seminal plasma samples from 19 (11%) patients were HCV RNA positive. The positive HCV viral load in semen was less than 600 IU/ml. None of the 90% fractions from HCV-infected patients were HCV RNA positive. Among the 93 co-infected patients, 10 were positive for HCV RNA in semen and three were HIV/HCV RNA positive in semen. CONCLUSIONS: Although HCV RNA was found in the semen of 11% of patients, no purified sperm fraction, or spermatozoa used in MAP were HCV RNA positive. The 90% purified sperm fraction discards the virus and must be used with care in MAP.

Adult↗
PubMed2006

Assessment of early virological response to antiviral therapy by comparing four assays for HCV RNA quantitation using the international unit standard: implications for clinical management of patients with chronic hepatitis C virus infection.

WHO International Standards for nucleic acid tests are used widely to compare the different assays used in HCV RNA quantitation. The aim of the study was to assess the impact of the international unit standard for measuring HCV RNA in the management of patients with chronic hepatitis C virus (HCV) infection. Twenty-seven naïve patients infected chronically by HCV were treated with ribavirin plus PEG-interferon-alfa-2b for 48 weeks. SVR was obtained for 16 patients (the other were non-responders). For HCV RNA quantitation, four assays were undertaken: Versant HCV RNA 3.0 (Bayer), Real time PCR (TaqMan, Roche), LCx HCV RNA (Abbott), and Cobas Amplicor-Monitor v2 (Roche). Considering a 2-log decline at Week 12 after the beginning of therapy, discordant results were found with the four HCV RNA methods in predicting SVR or non-response. At Week 4 and Week 12, significant differences were observed between Versant HCV RNA 3.0 versus PCR HCV Taqman, Versant HCV RNA 3.0 versus LCx HCV RNA, Cobas Monitor Amplicor HCV 2.0 versus LCx HCV RNA, and Cobas Monitor Amplicor HCV 2.0 versus PCR HCV Taqman (P < 0.001). The HCV RNA cutoff, given a 100% negative predictive value at Week 4 and Week 12, differed with the assays used to quantify HCV RNA, despite the use of the IU/ml units. Eighty-nine percent of serum values for HCV RNA were concordant by the IU standard. All assays, however, failed to detect HCV RNA in some cases. Despite the use of the IU standard HCV-infected patients might be monitored with only one assay.

Administration, Oral↗
PubMed2006

Biological markers of liver fibrosis and activity as non-invasive alternatives to liver biopsy in patients with chronic hepatitis C and associated mixed cryoglobulinemia vasculitis.

OBJECTIVE AND METHODS: We assessed the reliability of non-invasive biological scoring indexes (Fibrotest-Actitest [FT-AT], Forns, APRI, age-platelet, platelet, hyaluronic acid) as non-invasive alternatives to liver biopsy (LB) in 138 HCV-infected patients. RESULTS: Thirty-six of 138 (26%) patients had systemic vasculitis, 27% significant serum inflammation, 47% fibrosis (F2F3F4) on LB. The diagnostic value of FT (F2F3F4 vs. F0F1) was assessed by an AUC of 0.83, without difference regarding to systemic vasculitis or serum inflammation. A discordance between FT-AT and the Metavir scoring indexes, present in 29% of patients, was associated with serum hemolysis and male but not with systemic vasculitis or serum inflammation. The other non-invasive biological tests were not influenced by serum inflammation or systemic vasculitis but were less reliable than FT (P <or= 0.05). CONCLUSION: The FT-AT is a reliable non-invasive biochemical alternative to LB in HCV-infected patients with systemic vasculitis and is more reliable than other non-invasive biological indexes.

Adult↗
PubMed2006

Independent prospective multicenter validation of biochemical markers (fibrotest-actitest) for the prediction of liver fibrosis and activity in patients with chronic hepatitis C: the fibropaca study.

OBJECTIVES: Fibrotest (FT) and Actitest (AT) are biochemical markers of fibrosis and activity for use as a non-invasive alternative to liver biopsy in patients with chronic hepatitis C virus (HCV). The aim of this study was to perform an external validation of FT and AT and to study the discordances between FT/AT and liver biopsy in patients with chronic hepatitis C. METHODS: A total of 519 consecutive patients with chronic HCV were prospectively included in five centers, with liver biopsy and biochemical markers taken at the same day. Fifteen patients were excluded because their biopsies could not be interpreted. Diagnostic accuracies were assessed by receiver operating characteristic (ROC) curve analysis. RESULTS: Median biopsy size was 15 mm (range: 2-58), with 9 portal tracts (1-37) and 1 fragment (1-12). 46% (230/504) were classified F2-F4 in fibrosis and 39% A2-A3 in activity. FT area under ROC curve for diagnosis of activity (A2-A3), significant fibrosis (F2-F4), and severe fibrosis (F3-F4) were 0.73 [0.69-0.77], 0.79 [0.75-0.82], and 0.80 [0.76-0.83], respectively. Among the 92 patients (18%) with 2 fibrosis stages of discordance between FT and biopsy, the discordance was attributable to FT in 5% of cases, to biopsy in 4%, and undetermined in 9%. CONCLUSIONS: This prospective independent and multicenter study confirms the diagnostic value of FT and AT found in the princeps study and suggests that FT and AT can be an alternative to biopsy in most patients with chronic HCV.

Adolescent↗
PubMed2006

Real-time PCR assays for hepatitis C virus (HCV) RNA quantitation are adequate for clinical management of patients with chronic HCV infection.

Because of the use of viral kinetics during polyethylene glycol (PEG)-interferon-ribavirin therapy and the development of specific new anti-hepatitis C virus (anti-HCV) drugs, assessment of the efficacy of anti-HCV drugs needs to be based not on end-point PCR assays but on real-time PCR. The aim of this study was to determine if the two available commercial real-time PCR assays, the Abbott RealTime HCV assay and the Roche Cobas TaqMan HCV assay, can become the standard for HCV RNA quantification. We investigated the prognostic relevance of HCV RNA viral loads at baseline, week 4, and week 12 to a rapid and early virological response to antiviral therapy by using the two assays. Of 59 naïve patients chronically infected by HCV (41 infected with genotype 1) who were treated with ribavirin plus PEG-interferon alfa-2b for 48 weeks, 24 patients (41%) showed a sustained virological response (SVR). With the two assays, viral loads were highly correlated, irrespective of genotype (R2=0.94 for all cases). No difference in diagnostic value was found between the Abbott and Roche assays at week 4, with respective negative predictive values (NPVs) of 84% and 78% and positive predictive values (PPVs) of 62% and 56% (not significant), and at week 12, the respective NPVs were 91% and 90% and PPVs were 44% and 46% (not significant). At week 12, 83% (20/24) and 96% (23/24) of patients with SVR tested negative for HCV RNA by the Abbott and Roche assays, respectively (the difference is not significant). In conclusion, the high sensitivities and large dynamic ranges of the Abbott and Roche assays show that a single real-time quantitative PCR assay is fully adequate for clinical and therapeutic management of HCV.

Adult↗
PubMed2006

Expertise of laboratories in viral load quantification, genotyping, and precore mutant determination for hepatitis B virus in a multicenter study.

A national evaluation study was performed in 14 specialized laboratories with the objective of assessing their capacities to provide (i) hepatitis B virus (HBV) viral loads (VL), (ii) HBV genotypes, and(iii) identification of precore/core mutants. The panel consisted of 12 HBV DNA-positive samples with VLs from 2.8 to 9.1 log(10) copies/ml, different HBV genotypes (A to F), and 3 mutant and 9 wild-type samples at nucleotide 1896. The coefficients of variation of the mean VLs ranged from 2.4% to 10.4% with the Cobas HBV Monitor assay, from 1.8% to 5.5% with the Cobas TaqMan 48, from 1.5 to 26.2% with RealArt HBV PCR, and from 0 to 7% with branched DNA (bDNA). The Cobas Monitor assay underestimated the VLs of genotype F samples, with differences ranging from 1.4 to 2.4 log(10) copies/ml. The accuracies of genotype determinations ranged from 33% to 100%, and those of precore mutant determinations ranged from 25 to 100%. This study showed some drawbacks of two widely used assays: (i) Cobas Monitor has a narrow dynamic range and underestimates genotype F sample VLs and (ii) bDNA shows poor sensitivity and may fail to identify patients with low VLs. With higher performance in terms of analytical sensitivity combined with a larger dynamic range and an ability to quantify the main genotypes equally, real-time PCR methods appear more appropriate for accurate monitoring of HBV DNA quantification. Furthermore, the clinical implications of HBV genotyping and the determination of precore/core mutants need to be clearly stated to justify the standardization of these methods.

France↗
PubMed2005

Kinetics of hepatitis C virus RNA load during pegylated interferon alpha-2a and ribavirin treatment in naïve genotype 1 patients.

BACKGROUND: Pegylated interferon given for 24 or 48 weeks constitutes the most effective initial therapy for the treatment of chronic hepatitis C. It has been shown that viral load at week 2 appears the best time for predicting response to treatment. The objectives of this study were to assess whether the hepatitis C virus (HCV) RNA viral decline is predictive of sustained virological response (SVR) and to determine the best time for predicting complete response in our cohort of naïve patients treated with pegylated interferon alpha-2a (Peg-IFN alpha-2a) and ribavirin. RESULTS: Twenty patients treated with Peg-IFN alpha-2a and ribavirin for 48 weeks were studied. Six months after the end of treatment, a SVR (negative HCV RNA measured by PCR six months after the end of therapy) was obtained in 9 patients. Samples were obtained before and at week 2, 4, 8, and 12. At the end of week 2, viral load decreased more than 1.39 log in 8 out of the 9 patients with SVR and in 1 out of the 11 other patients. When we considered the viral load reduction from baseline to each week of treatment, week 2 appeared to be the best point time for predicting SVR, with a sensitivity of 91% (95%CI: 59;99), a specificity of 89% (52;98), a positive predictive value of 91% (59;99) and a negative predictive value of 89% (57;98). CONCLUSION: During treatment with Peg-IFN alpha-2a plus ribavirin in genotype 1 patients, when the main objective of the treatment is viral eradication, viral kinetics showed that week 2 appeared to be the best time point for predicting SVR. Our results must be further confirmed on a larger cohort.

Journal Article↗
PubMed2005

Accuracy of hyaluronic acid level for predicting liver fibrosis stages in patients with hepatitis C virus.

BACKGROUND: In patients with chronic hepatitis C virus, liver biopsy is the gold standard for assessing liver disease stage; nevertheless, it is prone to complications, some of them serious. Non-invasive methods have been proposed as surrogate markers for liver fibrosis. It was shown that serum hyaluronic acid (HA) level increases with the development for liver fibrosis. The aim of this study was to evaluate the diagnostic value of HA as well as to determine the HA level cut-off for predicting the presence or absence of fibrosis, severe fibrosis, and cirrhosis. RESULTS: 405 patients with chronic hepatitis C were prospectively included with biomarker measurement and liver biopsy done the same day: 151 in the training set (only biopsy lengths of 25 mm or more) and 254 in the validation set. For the discrimination of significant fibrosis, severe fibrosis, and cirrhosis in the training set, the areas under curve (AUCs) were 0.75 +/- 0.03, 0.82 +/- 0.02, and 0.89 +/- 0.03, respectively. Absence of significant fibrosis, severe fibrosis, and cirrhosis can be predicted by HA levels of 16, 25, and 50 microg/l, respectively (with negative predictive values of 82%, 89%, and 100%, in the same order). Presence of significant fibrosis, severe fibrosis, and cirrhosis can be predicted by HA levels of 121, 160, and 237 microg/l, respectively (with positive predictive values of 94%, 100%, and 57%, in the same order). CONCLUSION: In the validation set, HA was accurate in predicting significant fibrosis, severe fibrosis, and cirrhosis with AUCs of 0.73, 0.77, and 0.97, respectively. Moreover, accurate HA level cut-offs were defined for predicting significant fibrosis, severe fibrosis, and cirrhosis. Thus, the study supports that HA level may be clinically useful as a non-invasive marker for liver fibrosis and/or cirrhosis.

Journal Article↗
PubMed2005

Hepatitis B virus genotypes and extrahepatic manifestations.

BACKGROUND/AIMS: This study aimed at correlating the presence of extrahepatic manifestations with hepatitis B virus (HBV) genotypes in patients with chronic HBV infection. METHODS: This was a national (France), multicenter, retrospective, cross-sectional study. HBV genotypes were determined in 190 patients HBsAg-positive for at least 6 months and documented before any treatment. RESULTS: Patients were aged 42+/-15 years and mainly male (77%). Alcohol intake was high in 6% of them, ALT elevated in 73%; 27% were cirrhotic. All HBV genotypes were found, mainly A (24%), D (29%), C (11%), and E (10%). Thirty (16%) patients had clinical extrahepatic manifestations, mainly sensory-motor deficiency, sicca syndrome, myalgia, glomerulonephritis, and arthralgia-arthritis. Their presence was not related to any epidemiologic, viral (including genotypes) or hepatic factor, but to a higher platelet count (P=0.004). Twenty-nine (15%) patients had biological extrahepatic manifestations, mainly anti-smooth muscle, antinuclear, and anti-nucleosome antibodies. Their presence was related only to anti-HBe antibodies positivity (P=0.007) or elevated platelet count (P=0.003). Carrying precore mutant HBV increased by 2.8 folds the risk to have at least one extrahepatic biological manifestation. CONCLUSIONS: No relationships between HBV genotypes and the presence of extrahepatic manifestations were evidenced in patients with chronic HBV infection.

Adolescent↗
PubMed2005

Analytical variability of the Fibrotest proteins.

OBJECTIVES: The analytical variability of the Fibrotest (FT) parameters raises the issue of the test's reliability for routine use. Whereas standardization has been proposed by the International Federation of Clinical Chemistry (IFCC) for specific proteins, few data are available concerning the actual transferability of the FT proteins, i.e. haptoglobin, apolipoprotein A1 and alpha2 macroglobulin. The aim of this study was to evaluate the analytical variability of the FT proteins. DESIGN AND METHODS: During the FIBROPACA study, we evaluated 112 sera from patients with hepatitis C infection who underwent liver biopsy. We compared measurements of haptoglobin, apolipoprotein A1 and alpha2 macroglobulin by the autoanalyzers Immage (Beckman-Coulter) and the FT reference BNProspec (Dade-Behring). RESULTS: Optimal concordance was found for haptoglobin (correlation: y = 1.05x -0.09; correlation coefficient = 0.98). However, apolipoprotein A1 as determined with Immage was globally 12% lower than with BNProspec (correlation: y = 0.88x -0.05; correlation coefficient = 0.91) and alpha2 macroglobulin values were 40% greater with Immage than with BNProspec (correlation: y = 1.40x -0.46; correlation coefficient = 0.96). CONCLUSIONS: Inter-technique analytical variability of the Fibrotest parameters remains a major issue. After IFCC standardization of specific proteins, some discrepancies remain for alpha2 macroglobulin and, to a lesser extent, for apolipoprotein A1. National and international quality control programs would be useful to monitor analytical performance of protein assays.

Apolipoprotein A-I↗
PubMed2004

[The diagnostic tools of hepatitis C virus infections].

SERIOLOGICAL TESTS IN FIRST INTENTION: Aimed at revealing antibodies demonstrating the contact of the patient with the hepatitis C virus. There are two types of serological tests: ELISA for the global screening of various antibodies and immunoblot for the isolation of the various antibodies. QUALITATIVE RNA OF HCV: The positive qualitative detection of RNA of the hepatitis C virus in a patient exhibiting anti-HCV antibodies confirms an active infection. In the case of negative qualitative detection in a patient exhibiting anti-HCV antibodies, viral eradication is probable and should be controlled later on. MEASURING THE VIRAL LOAD: Two types of measuring techniques are used to quantify the circulating viral RNA: gene amplification and amplification of the signal. The extent of the viral load will help to guide the selection and duration of the anti-HCV dual therapy, associating pegylated interferon and ribavirin. The kinetics of the decrease in viral load are part of the therapeutic follow-up. HCV typing Many viral strains have been isolated, demonstrating its genetic variability and have led to the development of genotyping. The latter is useful in selecting the right therapy and duration of treatment, because the response depends on the genotype (better response rate for the genotypes 2 and 3).

Antibodies, Viral↗