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L Musset

Publications and source records attributed to L Musset.

At least 37 records · Page 2Linked to original sources

Pattern of HCV antibodies with special reference to NS5A reactivity in HCV-infected patients: relation to viral genotype, cryoglobulinemia and response to interferon.

BACKGROUND/AIMS: We aimed to compare the anti-hepatitis C virus reactivity in confirmatory assays (RIBA 3.0 Ortho Diagnostic and INNO-LIA HCV Ab III Innogenetics) among patients infected with different hepatitis C virus genotypes, with or without cryoglobulinemia, and in patients treated with interferon. METHODS: One hundred and three patients followed in our hepatogastroenterology unit were included in the study and compared to 320 consecutive patients tested using RIBA 3.0. Seventy-nine of the 103 patients were treated with interferon. Long-term responders to interferon were defined as having normal alanine aminotransferase levels and being HCV RNA negative 6 months after the end of treatment. Initial responders were defined as having normal alanine aminotransferase levels at the end of interferon therapy but abnormal alanine aminotransferase levels and/or detectable HCV RNA during the following 6 months. Non-responders were defined as still having elevated alanine aminotransferase during and after interferon. Serological tests (RIBA and INNO-LIA) were performed according to the manufacturers' instructions. HCV RNA was detected by nested polymerase chain reaction. Hepatitis C virus genotype was determined by using a Line Probe Assay (Innogenetics). RESULTS: There was no significant difference in the pattern of hepatitis C virus reactivity according to the hepatitis C virus genotype or presence of cryoglobulinemia. Twenty-three patients were classified as non-responders, 35 as initial responders, 21 as long-term responders. NS5 reactivity was significantly different (p<0.01) between these three groups: 34% of non-responders (8/23) had RIBA 3.0 NS5 reactivity and 13% (3/23) were reactive in the INNO-LIA III. Almost all long-term responders (95%) had NS5 reactivity by both RIBA 3.0 and INNO-LIA III. CONCLUSION: We conclude that patients who respond to interferon have stronger reactivity against NS5 antigens than non-responders. Molecular changes in the NS5A region may be responsible for such differences, as recently suggested.

Antiviral Agents↗

No evidence for abnormal immune activation in peripheral blood T cells in patients with hepatitis C virus (HCV) infection with or without cryoglobulinaemia. Multivirc Group.

The aim of this study was to investigate the peripheral blood lymphocyte (PBL) phenotypes and T cell repertoire in patients with HCV infection, with or without mixed cryoglobulinaemia (MC). The patients were: Group 1, 23 patients with HCV infection and MC; Group 2, 14 patients with HCV infection but without MC; Group 3, 10 patients with symptomatic essential MC. Twenty healthy blood donors were used as controls. Blood lymphocyte counts were determined, and flow cytometry was used to measure proportions of B cells (CD19+), natural killer (NK) cells (CD16+CD56+), T cells (CD3+), CD4+ T cell subsets (memory CD4+CD45RO+; naive CD4+CD45RO-; Th0/Th2CD4+CD7-; activated CD4+CD25+), and CD8+ T cell subsets (immunoregulatory CD8+CD57+; cytotoxic CD8+S6F1+, activated CD8+CD25+). Bias in the usage of T cell receptor (TCR) Vbeta chains was studied in a subgroup of 10 representative patients of Group 1 using a polymerase chain reaction (PCR) analysis of the Vbeta segments with a series of 20 oligonucleotides specific for the Vbeta families. The three groups were comparable for blood lymphocyte counts, and we observed no abnormal repartition of the following PBL subsets: T cells (CD3+), CD4+ and CD8+ subpopulations, B cells (CD19+), and the NK cells (CD16+56+). In none of the groups could we observe lymphocyte ex vivo activation as assessed by the normal expression of the activation cell markers: CD25 on CD4+ or CD8+ T cells, or CD5 on B cells. The repartition of naive and memory (CD45RO-/RO+) CD4+ T cells was normal and we did not observe any amplification of the CD4+CD7- T cell subset differentiated in vivo in Th0/Th2 cells. There was no significant amplification of cytotoxic (SF6+) and immunoregulatory (CD57+) CD8+ T cells in HCV patients with or without MC. Finally, the usage of Vbeta families in the TCR repertoire was normal in the patients tested. In patients with chronic HCV infection, with or without MC, we did not find any significant expansion or abnormal activation of T, B and NK cell subsets, dysbalance of the naive/memory subsets, or expansion of the Th0/Th2 subpopulation. These findings differ from the profound immune alterations that are observed in other chronic infections such as HIV or Epstein-Barr virus. Although this study was restricted to the peripheral blood, it suggests that in chronic HCV infection, MC is not the consequence of a chronic activation or dysregulation of the peripheral blood immune cells.

Adult↗

Parvovirus B19 infection, hepatitis C virus infection, and mixed cryoglobulinaemia.

BACKGROUND: Infection with human parvovirus B19 (B19) has been reported in a few patients with various vasculitis syndromes. Mixed cryoglobulinaemia (MC), a model of small vessel size vasculitis, may result from numerous infectious diseases, particularly hepatitis C virus (HCV) infection. AIM: To assess the prevalence of seric B19 infection markers in a large series of patients with MC, with or without HCV infection. PATIENTS AND METHODS: Sixty-four patients were studied: essential MC (EMC, n = 19), MC associated with non-infectious diseases (non-essential MC, n = 9), and patients with HCV infection with (HCV-MC, n = 18) or without MC (HCV-no-MC, n = 18). Patients were considered to have MC if two successive determinations of their serum cryoglobulin concentration were above 0.05 g/l. Serum samples were analysed for specific IgG and IgM antibodies to B19 by enzyme immunoassay. B19 DNA detection was performed by polymerase chain reaction using a set of primers located in the VP1 gene, separately in serum and in cryoprecipitates to investigate a possible capture of B19 DNA in cryoprecipitate. The study also looked for a possible enrichment for of IgG antibodies to B19 in MC. RESULTS: The presence of specific IgG antibodies to B19 was found in 68% EMC, 56% non-essential MC, 78% HCV-MC, and 78% HCV-no-MC. No patient of either group had specific IgM antibodies to B19, or B19 DNA in serum or in cryoprecipitate. Overall, IgG antibodies to B19 were found in 46 of 64 (72%) serum samples, a prevalence quite similar to the prevalence in general adult population (> 60%). A specific enrichment of IgG antibodies to B19 in the MC was not found. CONCLUSION: These results suggest that B19 infection is neither an aetiological factor of EMC, nor a cofactor that may lead to MC production in patients with chronic HCV infection.

Antibodies, Viral↗

Variations of serum IgG subclass levels in hepatitis C virus infection during interferon-alpha therapy.

Serum IgG1 levels are selectively increased in patients with chronic hepatitis C virus (HCV) infection. In 15 patients who received interferon (IFN)-alpha therapy, serum levels of immunoglobulin classes and IgG subclasses were measured during treatment and after it was discontinued. In spite of important individual variations, mean IgG, IgG1, IgA and IgM levels decreased during therapy and tended to return to pre-treatment levels afterwards, with no detectable correlation with clinical and biological parameters. These results suggest an effect of IFN-alpha on in vivo immunoglobulin production, in HCV carriers.

Adult↗

Increased serum concentration of IgA2 subclass and IgA2/IgA1 ratio: specific markers of chronic alcoholic abuse?

Enhanced serum IgA concentrations are common in alcoholic liver cirrhosis, but functional differences between IgA subclasses and their relation with interleukin-6 (IL-6) have not been described. Distinct immunoregulatory mechanisms may exist that selectively affect one subclass. This possibility prompted us to investigate the distribution of IgA1 and IgA2 subclasses in the serum of 25 heavy alcohol drinkers (alcohol: 80 to 200 g per day) without clinical disorders, in comparison with 35 patients affected by alcoholic liver cirrhosis, 29 viral hepatitis patients and 33 social drinkers as a control group. Mean (+/- SD) IgA2 concentration (0.56 +/- 0.31 g/l) was significantly increased (p < 0.01) in heavy alcohol drinkers, with an IgA2/IgA1 ratio of 0.33 +/- 0.12, while the mean total IgA concentration was similar to the control group. Mean IgA1 and IgA2 concentrations were significantly increased (p < 0.001) in alcoholic liver cirrhosis patients (6.13 +/- 4.52 g/l and 1.83 +/- 1.93 g/l respectively, with an IgA2/IgA1 ratio of 0.32 +/- 0.19) and viral hepatitis patients (3.66 +/- 2.59 g/l and 0.69 +/- 0.67 g/l respectively, with an IgA2/IgA1 ratio of 0.21 +/- 0.14) High serum IL-6 concentrations (34 +/- 33 ng/l) were correlated with elevated IgA1 and IgA2 concentrations only in patients with alcoholic liver cirrhosis. IgA2 subclass and IgA2/IgA1 ratio could therefore be used as markers of chronic alcohol abuse directly related to the extent and duration of the alcohol abuse and the effectiveness of alcohol withdrawal.

Adult↗

Anticardiolipin, anti-beta2-glycoprotein I, and antinucleosome antibodies in hepatitis C virus infection and mixed cryoglobulinemia. Multivirc Group.

OBJECTIVE: To investigate anticardiolipin antibodies (aCL), anti-beta2-glycoprotein I (anti-beta2GPI), and antinucleosome antibodies in patients with hepatitis C virus (HCV) with or without mixed cryoglobulinemia. aCL can appear in infectious diseases, but are not then associated with thrombotic events. Antibodies directed to beta2GPI, a co-factor of aCL, have been said to be associated with the presence of "autoimmune" aCL. About 50% of cases of essential mixed cryoglobulinemia are associated with HCV infection. High prevalence of autoantibodies directed to nuclear antigens has been found in HCV infection but the prevalence of antibody to nucleosome has not yet been reported. METHODS: Group 1: 29 patients with chronic HCV infection and mixed cryoglobulinemia. Group 2: 17 patients with chronic HCV infection but without mixed cryoglobulinemia. To analyze the possible effect of mixed cryoglobulinemia itself on aCL production, we also studied 22 patients with essential mixed cryoglobulinemia and no HCV infection (Group 3). In addition, 96 healthy blood donors were used as a control group (Group 4). Mixed cryoglobulinemia was detected by immunofixation. Anti-HCV antibodies were detected by 3rd generation tests, aCL, anti-beta2GPI, and antinucleosorne antibodies were detected by ELISA. In patients with mixed cryoglobulinemia, we also looked for aCL separately in cryoprecipitate and in serum after extraction of mixed cryoglobulins to investigate a possible "capture" of aCL in the cryoprecipitate. RESULTS: IgG aCL were more frequently found in patients with HCV than in controls [9/46 (20%) vs 2/96 (2%); p < 0.001]. The prevalence of aCL was similar in patients with HCV with or without mixed cryoglobulinemia (6/29 vs 3/17; p = NS). No patient with positive aCL had anti-beta2GPI, antinucleosome antibodies, thrombotic events, or thrombocytopenia. IgG aCL were more frequent in patients with mixed cryoglobulinemia, whatever their status for HCV infection, than in subjects without mixed cryoglobulinemia [8/51 (16%) vs 5/113 (4%); p < 0.02]. The prevalence of aCL was similar in patients with type II or type III mixed cryoglobulinemia. When we looked for aCL separately in serum and in cryoprecipitate, we did not find aCL in cryoprecipitate. In patients with HCV, the prevalence of aCL was not different whether patients were treated or not with interferon alpha. CONCLUSION: IgG aCL are frequently found in patients with HCV regardless of status for mixed cryoglobulinemia. These aCL have the characteristics of infection related aCL: low titer, absence of thrombotic events, and absence of anti-beta2GPI. The high proportion of aCL in patients with mixed cryoglobulinemia compared to those without, and the absence of antinucleosome antibodies, suggest that these aCL may be secondary to endothelial damage induced by mixed cryoglobulinemia or HCV itself, rather than to nonspecific polyclonal lymphocyte activation.

Antibodies, Anticardiolipin↗

[Mixed cryoglobulinemia in hepatitis C virus infection].

Mixed cryoglobulinemia occurs in about half of all patients with chronic hepatitis C. Mixed cryoglobulinemia results from a lymphoproliferative disorder caused by polyclonal lymphocyte B proliferation (type III) or expansion of a B-cell clone producing monoclonal Ig with anti-immunoglobulin activity (type II). Among the different viral infections studied to date (hepatitis A or B, cytomegalovirus, Epstein-Barr or herpes simplex virus) none except hepatitis C has been formally linked to cryoglobulinemia. The mechanisms involved with the hepatitis C virus and persistant cryoglobulinemia are unknown. Several studies have shown that the hepatitis C virus plays a distinct role in the pathogenesis of cryoglobulinemia. The high content of anti-HVC antibodies and viral RNA in the cryoprecipitates suggests that entire viral particles or encapsidized viral RNA may be involved. Viral variability over time and within the same individual might be responsible for repeated antigenic stimulation of the immune system leading to proliferation or expansion of the B-cell clone.

Cryoglobulinemia↗

Cryocrystalglobulinemia as a cause of systemic vasculopathy and widespread erosive arthropathy.

This report describes the case of woman who was admitted to the hospital for highly destructive axial and peripheral arthropathy in association with acute malignant hypertension and skin purpura. Type I IgGkappa serum cryoglobulinemia was identified and was classified as a monoclonal gammopathy of unknown significance. Cryoglobulin was shown to crystallize in the serum and synovium fluid and was responsible for both granulomatous microcrystalline synovial inflammation and occlusive vasculopathy in the kidneys and skin. Cryocrystalglobulinemia pathogenicity and therapeutic implications are discussed.

Arthrography↗

Hepatitis C virus genotypes and subtypes in patients with hepatitis C, with and without cryoglobulinemia.

BACKGROUND/AIMS: Recent reports have shown a high frequency of anti-hepatitis C virus antibodies in patients with cryoglobulinemia. The factors involved in the production of cryoglobulins in hepatitis C virus-infected patients are unknown. To assess the role of hepatitis C virus genotypes in the pathogenesis of mixed cryoglobulinemia, we analyzed their prevalence in a group of 118 hepatitis C virus-infected patients according to the presence or absence of cryoglobulins. METHODS: The hepatitis C virus genome was typed using the Line Probe Assay (LiPA, Innogenetics), for the most common genotypes (1a, 1b, 2a, 2b, 3, 4 or 5). RESULTS: Cryoglobulinemia was diagnosed in 60 (51%) patients, 33 (55%) of whom had type II and 27 (45%) type III cryoglobulins. Forty-four (37%) patients had no cryoglobulinemia and 14 (12%) patients had transient cryoglobulins. Cryoglobulins were significantly less prevalent in patients infected by genotype 1a. We found no statistical link between the hepatitis C virus genotype and the presence of symptomatic cryoglobulinemia, or the hepatitis C virus genotype and the type (II or III) of cryoglobulin. Interestingly, all six patients infected by hepatitis C virus genotype 4 or 5 had cryoglobulins. CONCLUSIONS: In patients with hepatitis C virus infection, cryoglobulinemia is not strongly associated with a particular HCV genotype or subtype. The mechanism by which cryoglobulins are produced remains to be elucidated.

Adult↗

Peripheral neuropathy associated with essential mixed cryoglobulinaemia: a role for hepatitis C virus infection?

BACKGROUND: The prevalence of hepatitis C virus (HCV) infection has been estimated at 43 to 84% in patients with essential mixed cryoglobulinaemia in recent large series. Some of these cases have been successfully treated with interferon-alpha. The objective was to evaluate the prevalence and the possible role of HCV infection in essential mixed cryoglobulinaemia. METHODS: Fifteen patients (eight men and seven women; mean age: 61.2 (SD 16.5) years) with peripheral neuropathy (10 polyneuropathies and five multifocal mononeuropathies) and essential mixed cryoglobulinaemia were tested for serum anti-HCV antibodies. RESULTS: Antibodies were found in 10 of 15 patients involving either polyneuropathies (seven patients) or multifocal mononeuropathies (three patients). Electrophysiological studies and teased nerve fibre studies (in seven patients) allowed neuropathies to be classified as predominantly sensory axonopathies. Compared with HCV-negative (HCV -) patients, HCV-positive (HCV +) patients had a more pronounced and more widespread motor deficit; motor nerve conduction velocities in peroneal and median nerves were more impaired in HCV + patients, although significance was not reached except for the mean value of the amplitude of the compound muscle action potentials of the median nerves (P < 0.05); necrotising vasculitis was found in two of nine nerve biopsies from the HCV + patients studied and in none of the three HCV - patients. In addition, HCV + patients had more frequent cryoglobulin related cutaneous signs, higher aminotransferase and serum cryoglobulin concentrations, lower total haemolytic complement concentrations, and more frequent presence of rheumatoid factor. A liver biopsy performed in eight HCV + patients disclosed a range of lesions, from chronic active hepatitis (six patients) to persistent hepatitis (two patients). Lastly, treatment with interferon-alpha conducted over six months in two patients seemed to improve the peripheral neuropathy. CONCLUSIONS: Patients with peripheral neuropathy and essential mixed cryoglobulinaemia should be tested for anti-HCV antibodies to determine the appropriate treatment.

Adult↗

Essential mixed cryoglobulinemia. A comparative study of dermatologic manifestations in patients infected or noninfected with hepatitis C virus.

BACKGROUND AND DESIGN: An association between essential mixed cryoglobulinemia and hepatitis C virus (HCV) infection has been reported. Dermatologic manifestations are a classic presenting complaint in essential mixed cryoglobulinemia. The aim of this study was to compare the frequency and the nature of dermatologic manifestations in essential mixed cryoglobulinemia according to the presence of anti-HCV antibodies. Sixty-two consecutive patients with essential mixed cryoglobulinemia were tested for anti-HCV antibodies. Dermatologic manifestations were systematically assessed. RESULTS: Anti-HCV antibodies were detected in 35 patients. Palpable purpura corresponding histologically to leukocytoclastic vasculitis was the more frequently observed dermatologic manifestation and occurred mainly in HCV-antibody-positive patients. The patients with purpura had significantly higher serum cryoglobulin levels than patients without purpura. CONCLUSIONS: The frequency of palpable purpura is higher in HCV-antibody-positive patients and is related to the serum cryoglobulin levels.

Cryoglobulinemia↗

Immunochemical characterization of monoclonal IgG containing mixed cryoglobulins.

Monoclonal IgG-containing type II cryoglobulins (CG) from 25 patients, most affected with autoimmune or inflammatory diseases, were characterized using a Western blotting procedure. Rheumatoid factors were measured by ELISA. Out of the 25 type II CG, 14 contained a single monoclonal IgG and 11 contained several distinct monoclonal Ig, as assessed by the electrophoretic mobility and isotypy of the narrow bands. Comparison of blots revealed by anti-IgG subclass antibodies in the patients' sera and CG showed a clear-cut enrichment of CG in both polyclonal and monoclonal IgG1 and IgG3. All monoclonal IgG in the CG belonged to the IgG1 or IgG3 subclasses. CG also contained more detectable RF of the IgM class than did the corresponding sera. Using conventional methods, the present CG either could not be typed or were all (immunoelectrophoresis) or often (immunofixation) classified as type III. The results challenge the classical classification of CG and show the necessity of the use of sensitive techniques for immunochemical characterization of mixed CG.

Adult↗

Mixed cryoglobulinemia and hepatitis C virus.

BACKGROUND: Mixed cryoglobulinemia (MC) is frequently associated with clinical and biological evidence of liver disease and has recently been reported in cases of hepatitis C virus (HCV) infection. The aim of this study was to assess prospectively in a large series of MC patients: (1) the prevalence of HCV markers (anti-HCV antibodies and HCV RNA in serum and cryoprecipitate); (2) the main clinical, biologic and liver histologic features in patients with or without HCV infection. PATIENTS: One hundred fifteen consecutive unselected MC patients were studied: 45% had well-defined underlying diseases ("nonessential" MC). Fifty-five percent with no cause of MC were considered to have "essential" MC and were subjected to in-depth examination. METHODS: Patients were considered to have MC if two successive determinations of their serum cryoglobulin level were above 0.05 g/L. Anti-HCV antibodies (Ab) were detected in all patients by second-generation tests (ELISA, RIBA). We also looked for HCV RNA sequences amplified by polymerase chain reaction (PCR) in the sera and cryoprecipitates of 39 patients; HBs antigen, anti-HBs Ab and anti-HBc Ab in all patients; and HBV DNA in 20 sera and 17 cryoprecipitates. Quantitative HCV Ab and RNA studies were performed on whole serum, cryoprecipitates, and supernatants. Clinical features were recorded retrospectively for each patient. Liver biopsies from 23 anti-HCV Ab-positive and 7 anti-HCV Ab-negative patients were examined histologically, with qualitative and quantitative analysis. RESULTS: Anti-HCV Ab were found in 47/115 (41%) patients by ELISA and RIBA: 33/63 (52%) essential MC and 14/52 (27%) nonessential MC. Among the 63 essential MC patients, the 33 anti-HCV Ab-positive (Group 1) were compared to the 30 anti-HCV Ab-negative patients (Group 2). Group 1 patients had more cutaneous involvement (Raynaud's phenomenon, purpura, livedo, distal ulcers, or gangrenous changes) (17 versus 5: p = 0.004), higher alanine aminotransferase levels (110 +/- 22 versus 41 +/- 10 IU; p < 0.005), higher serum cryoglobulin levels (0.35 +/- 0.07 versus 0.12 +/- 0.04 g/L; p = 0.01), lower CH50 (28 +/- 3 versus 44 +/- 2 CH50/mL; p = 0.0001) and lower C4 levels (0.20 +/- 0.02 versus 0.29 +/- 0.03 g/L; p < 0.04). The prevalence of HBV serum markers was low in both groups, and HBV DNA was never detected in any of the sera and cryoprecipitates tested. HCV RNA sequences were detected in 10/16 (63%) sera and 12/16 (75%) cryoprecipitates from Group 1 patients, whereas they were not in the sera or cryoprecipitates from 23 Group 2 patients. Using quantitative PCR, HCV RNA in cryoprecipitates was concentrated 20 to 100 times despite the absence of significant anti-HCV Ab concentration in these samples. Histologic examination of liver biopsies revealed a spectrum of lesions ranging from chronic active hepatitis to cirrhosis, but Knodell's score did not differ between the groups. CONCLUSION: (1) About 50% of the essential MC patients had anti-HCV Ab, and these patients had more severe cryoglobulinemia-associated clinical and biological signs; (2) HCV RNA sequences were found in the large majority of sera and cryoprecipitates from patients with essential MC and anti-HCV Ab and were more concentrated in cryoprecipitates than in supernatants. These results suggest a role for HCV in the pathogenesis of MC and indicate that many cases of essential MC may be secondary to HCV infection and thus nonessential.

Adult↗