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G Teuber

Publications and source records attributed to G Teuber.

33 records · Page 2Linked to original sources
PubMed1999

Improved correlation between multiple mutations within the NS5A region and virological response in European patients chronically infected with hepatitis C virus type 1b undergoing combination therapy.

BACKGROUND/AIMS: Studies from Japan showed that HCV-1b isolates with at least four amino acid changes within NS5A2209-2248 compared with the prototype sequence HCV-J are more sensitive to interferon than isolates with a prototype sequence. However, the data were not unequivocally confirmed in studies from other geographical areas. These discrepancies may be explained by differences in the prevalence of multiple mutations within the NS5A2209-2248 and/or the treatment efficacy. METHODS: In the present study, we therefore investigated the correlation between NS5A2209-2248 sequences of HCV-1b isolates and sustained virological response in 72 European patients treated with 3x6 MU interferon-a per week with (n = 26) and without (n = 46) ribavirin (1000-1200 mg/day). Serum HCV RNA was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and the NS5A2209-2248 region was analyzed by sequencing of PCR products or individual clones. RESULTS: Compared with HCV-1b prototype sequences, 19 patients (26%) had no amino acid changes (prototype), 47 patients (65%) had 1-3 mutations (intermediate type) and six patients (8%) had at least 4 mutations in the NS5A2209-2248 region (mutant type). Nine of the 12 patients with sustained virological response were infected with an intermediate type HCV-1b, the remaining three patients revealed a mutant type HCV-1b. A sustained virological response was achieved in three of four patients with a mutant type HCV-1b treated with interferon-alpha and ribavirin, but in none of the mutant type HCV-1b infected patients treated with interferon-a alone. Quasispecies analysis of HCV in the NS5A2209-2248 region showed only minor heterogeneity of the amino acid sequence. CONCLUSIONS: The prevalence of mutant type HCV-1b isolates in European patients is low. In patients treated with combination therapy interferon-a and ribavirin, a correlation between mutant type HCV-1b isolates and sustained virological response was observed. The discrepancies between previous studies appear to be related to the efficacy of antiviral treatment and to the low prevalence of mutant type HCV-1b isolates in Western countries.

Adult↗
PubMed1999

Interferon-alpha improves glucose tolerance in diabetic and non-diabetic patients with HCV-induced liver disease.

This pilot study was initiated to evaluate factors controlling glucose tolerance in patients with hepatitis C virus-induced liver disease before and after therapy with recombinant interferon-alpha (r-INF-alpha). Fifteen patients with histologically and serologically proven hepatitis C infection underwent oral and frequently sampled intravenous glucose tolerance tests (FSIGTT) before and after four months of therapy (6 x 106 U r-INF-alpha, subcutaneously, three times a week). Glucose, insulin and C-peptide data from FSIGTT were analysed using the minimal modeling technique to determine insulin sensitivity, glucose effectiveness and first and second phase insulin secretion. According to the WHO criteria 13 patients, had normal glucose tolerance; diabetes mellitus was diagnosed in 2 patients. In the morning following the last r-INF-alpha injection four months later, insulin sensitivity improved significantly in hepatitis C virus-infected patients with normal glucose tolerance (2.17 +/- 0.37 vs. 6.18 +/- 0.94 10(-4) min(-1) per microU/ml, p < 0.001) and with diabetes mellitus (0.86 to 2.61; 0.46 to 1.06 10(-4) min(-1) per microU/ml). This effect was independent of the extent of fibrosis, virus load before treatment and therapy response. First phase insulin secretion increased in non-diabetic (139.2 +/- 17.1 vs. 200.0 +/- 32.7, p < 0.05) and diabetic patients with HCV infection (55.24 to 118.5; 84.23 to 261.1). Moreover, free fatty acid concentrations in all HCV-infected patients were significantly reduced (0.48 +/- 0.01 vs 0.21 +/- 0.03 mmol/l, p < 0.01). Therapy with recombinant interferon-alpha is associated with an amelioration of glucose tolerance in non-diabetic and diabetic HCV-infected patients.

Adult↗
PubMed1999

Interferon-antibodies and the breakthrough phenomenon during ribavirin/interferon-alpha combination therapy and interferon-alpha monotherapy of patients with chronic hepatitis C.

BACKGROUND/AIMS: The significance of interferon antibodies with respect to response to treatment in patients with chronic hepatitis C treated with interferon-alpha (INF-alpha) remains a matter of debate. The influence of ribavirin on IFN-antibody formation in combination therapy with IFN-alpha has not yet been studied. Therefore we evaluated the relationship between IFN-antibodies and response to ribavirin/IFN-alpha combination therapy and IFN-alpha monotherapy. METHODS: We studied 169 patients with chronic hepatitis C who were treated either with IFN alpha 2a (6 MU, thrice weekly) alone or in combination with ribavirin (14 mg/kg per day) for twelve weeks. Thereafter, patients who achieved a virological response (HCV-RNA-negative) were treated with 3 MU IFN-alpha thrice weekly for another 40 weeks. IFN antibodies were analyzed and quantified by a double-antigen sandwich enzyme immunoassay (EIA). In 86 patients two neutralization assays--an antiviral neutralization assay as well as an antiproliferative neutralization assay--were performed in addition. The relationship of the development of IFN-antibodies with the virologically defined response to treatment was analyzed. RESULTS: Ribavirin did neither influence the prevalence nor the level of IFN-antibodies. The frequencies of IFN-antibody formation did not differ in the response groups. However, patients with breakthrough showed significantly higher IFN-antibody titers as compared to responder at end of treatment (median 1,336 BU/ml vs. 148 BU/ml; p = 0.018). Among the breakthrough patients those with IFN-antibodies showed the reappearance of HCV-RNA during therapy significantly earlier (median week 24) than those without IFN-antibodies (median week 32; p = 0.03). CONCLUSION: The addition of ribavirin to IFN-alpha does not influence the formation of IFN-antibodies. The development of high-titer IFN-antibodies during IFN-alpha or ribavirin/IFN-alpha therapy of patients with chronic hepatitis C may account for the early occurrence of breakthrough in some patients, while other mechanisms seem to be responsible for this phenomenon in the majority of the afflicted patients.

Adult↗
PubMed1998

Hepatitis C virus dynamics in vivo: effect of ribavirin and interferon alfa on viral turnover.

Treatment of patients with chronic hepatitis C with recombinant interferon alfa (rIFN-alpha) can cause a decrease of serum transaminases and hepatitis C virus (HCV) RNA. Recent trials evaluating combination therapy of IFN-alpha and ribavirin suggested a potential synergistic effect. From serial measurements of serum HCV RNA concentrations following treatment-induced perturbation of the balance between virus production and clearance, we compared the antiviral efficacy of both IFN-alpha alone and IFN-alpha in combination with ribavirin. Chronically HCV-infected patients were treated with either 3 x 3 MU or 3 x 6 MU rIFN-alpha per week or 3 x 6 MU rIFN-alpha plus 14 mg/kg of body weight ribavirin per day. The time-dependent HCV RNA concentrations during antiviral treatment were analyzed by iterative least-squares regression. After initiation of antiviral therapy, HCV RNA declined exponentially below the detection limit of the reverse-transcription polymerase chain reaction assay (1,000 HCV RNA molecules per milliliter) in 10 of 26 (39%), 10 of 19 (53%), and 10 of 18 patients (56%) treated with 3 x 3 MU, 3 x 6 MU rIFN-alpha without and with ribavirin, respectively. Viral clearance from serum was faster in patients treated with 3 x 6 MU rIFN-alpha (t1/2 = 0.23 +/- 0.15) compared with patients treated with 3 x 3 MU rIFN-alpha per week (0.67 +/- 0.36 days) (P < .004). However, half-lives of viral clearance were similar in patients treated with rIFN-alpha or rIFN-alpha plus ribavirin. For virus release from infected hepatocytes, absence and presence of ribavirin yielded half-lives of t1/2 = 2.54 +/- 2.10 and t1/2 = 1.99 +/- 1.70, respectively, indicating that ribavirin does not significantly inhibit HCV production. In conclusion, the data of the present study indicate that higher rIFN-alpha doses accelerate viral clearance from serum. Ribavirin (14 mg/kg/d), however, lacks synergistic antiviral effects in the treatment of chronic hepatitis C with 3 x 6 MU rIFN-alpha per week.

Adult↗
PubMed1998

Effect of ribavirin on virus load and quasispecies distribution in patients infected with hepatitis C virus.

BACKGROUND/AIMS: The combination of ribavirin and interferon alfa has potent synergistic effects in the treatment of chronic hepatitis C. The antiviral mechanism of ribavirin is unknown. We investigated whether a transient initial antiviral effect of ribavirin was sufficient to improve the response to interferon. METHODS: Fifteen HCV-infected patients (ten male, five female; mean age 45.4+/-11.0 years) treated with ribavirin (1000-1200 mg) and 17 untreated patients with chronic hepatitis C (11 male, six female; mean age 45.6+/-9.9 years) were investigated. All patients were either non-responders to (n=19) or relapsed after (n=13) previous interferon treatment. Serum HCV-RNA concentrations and HCV quasispecies distribution were serially measured over 4 weeks by quantitative reverse transcription-polymerase chain reaction and single-strand conformation polymorphism analysis, respectively. RESULTS: In six of the 15 patients treated with ribavirin, but in none of the controls, serum alanine aminotransferase levels declined by at least 30%. Pretreatment HCV-RNA levels ranged from 5.0x10(5)-5.0x10(7) copies/ml. After initiation of ribavirin treatment, minor (0.5-1.0 log) or no changes (<0.5 log) in total hepatitis C viremia were observed in ten and five patients, respectively. In HCV-infected patients without treatment 7/17 patients had minor and 10/17 no changes in viremia. Polymerase chain reaction amplification of the hypervariable region-1 of HCV was successful in 13/15 treated and in 17/17 untreated patients. Changes in HCV quasispecies according to the single-strand conformation polymorphism band pattern occurred in only one patient treated with ribavirin and in three of the untreated patients. CONCLUSIONS: Ribavirin monotherapy has no initial antiviral effect on total hepatitis C viremia nor on HCV quasispecies. Unlike the rapid emergence of antiviral drug-resistant strains in HIV-infected patients, no viral escape phenomena are observed in HCV-infected patients treated with ribavirin.

Adult↗
PubMed1997

Enlargement of perihepatic lymph nodes in relation to liver histology and viremia in patients with chronic hepatitis C.

Inflammatory processes in organs frequently lead to hyperplasia of regional lymph nodes. In the present study, we investigated whether lymph node enlargement within the hepatoduodenal ligament may reflect the inflammatory activity within the liver of patients chronically infected with the hepatitis C virus (HCV). In 114 patients with chronic hepatitis C and 49 healthy controls, the total lymph node volume within the hepatoduodenal ligament was prospectively investigated by ultrasound. In patients with chronic hepatitis C, a liver biopsy was taken at the same occasion, and specimens were semiquantitatively evaluated by the histological activity index (HAI). Hepatitis C viremia was assessed by quantitative reverse transcription-polymerase chain reaction (RT-PCR). Genotyping was performed by a reverse hybridization assay. In 104 of 114 patients (91.2%) and in 45 of 49 healthy controls (91.8%), adequate visualization of the region of the hepatoduodenal ligament was achieved by ultrasound. Lymph nodes were detected in all patients with chronic hepatitis C and in 33 of 45 controls. The mean perihepatic lymph node volume in healthy controls (2.2 +/- 1.8 mL) was lower than in HCV-infected patients with mild to moderate inflammatory activity, severe inflammatory activity, and patients with cirrhosis (5.8 +/- 2.2 mL, 18.1 +/- 10.4 mL, and 22.8 +/- 18.8 mL, respectively). In patients with HCV-RNA levels of less than 10(6) copies/mL, the total lymph node volume was 5.8 +/- 1.6 mL and was significantly increased in patients with higher viremia (20.3 +/- 13.8 mL; P < 10(-6)). No correlation was found between the total lymph node volume within the hepatoduodenal ligament, HCV genotypes, and liver function test results. In conclusion, enlargement of perihepatic lymph nodes in patients with chronic hepatitis C is predictive for the presence of severe inflammatory activity. The mechanism of portal lymphadenopathy in patients with chronic hepatitis is unknown but appears to be related to viral replication within the liver and the immune-mediated inflammatory response of the host.

Adult↗
PubMed1996

Long-term follow-up of patients with chronic hepatitis B after interferon treatment.

We investigated the long-term effect of interferon-alpha treatment in patients with chronic hepatitis B with regard to the response status during treatment. 97 patients with chronic hepatitis B, including 18 patients with active cirrhosis Child A, were followed for 12-110 months (mean: 40.5 months) after interferon-alpha treatment. At the end of treatment complete response with loss of HBeAg and HBV-DNA was observed in 32 patients, partial response with loss of HBV-DNA in 30 patients and non-response with persistence of HBeAg and HBV-DNA in 35 patients. Overall, delayed virological improvement was observed in 43% of the 97 patients during follow-up. Delayed clearance of HBsAg occurred more frequently in complete responders (25%) than in partial responders (13%, P = n. s.) and non-responders (3% p = 0.0217). 39% of the partial and non-responders lost HBeAg during the follow-up period. HBsAg and HBeAg clearance rates were increased in female patients compared to males (HBsAg: 21% vs. 12%, p = n. s.; HBeAg: 47% vs. 32%, p = 0.0045). Reactivation of the disease was seen in 28% of the complete responders. In the 18 patients with active cirrhosis, short- and long-term response rates were impaired. Only, 4/18 patients had a complete response during treatment and two of these patients suffered reactivation during follow-up. One patient underwent liver transplantation and five patients died due to complications of cirrhosis. Thus, in patients without apparent cirrhosis interferon-alpha treatment has a considerable long-term effect with regard to the enhanced rate of HBsAg and HBeAg clearance during prolonged follow-up.

Adult↗
PubMed1996

Risk factors for the transmission of hepatitis C.

BACKGROUND: Due to the availability of testing for antibodies to the hepatitis C virus (anti-HCV) and with the use of the polymerase chain reaction (RT-PCR) to detect HCV-RNA, more sensitive and specific measures can be applied to assess routes of HCV transmission. The aim of the present study was to investigate possible risk factors for transmission of HCV. METHODS: 160 consecutive patients with chronic hepatitis C (mean age 47.1 +/- 14.1 yr) attending a hepatology out-patient clinic were interviewed to identify transmission risk factors. Genotyping of HCV isolates was performed by direct sequencing of RT-PCR products in the 5'-noncoding and the NS-5 region. RESULTS: The risk factors of HCV infection were as follows: transfusion of blood or blood products 34.4%, intravenous drug abuse 20.6%, heterosexual contact 3.8%, occupational risk 1.9% and tattoo 0.6%. In 62/160 (38.7%) the route of transmission remained unknown. In one HCV-infected couple we analyzed the nucleotide sequences of the NS-5 region of the respective HCV isolates and found almost complete sequence homology (> 97%). The majority of patients with post-transfusional or unknown mode of transmission were infected with genotype HCV-1a and -1b, while in 6/10 patients with previous i.v. drug abuse, genotype HCV-3a was present. We found no evidence that the mode of disease acquisition influences the course of liver disease. CONCLUSION: The majority of patients with chronic hepatitis C have a classical parenteral transmission risk factor. In our study, no source of HCV acquisition was identified in 38.7% of patients. It may well be that the major factors in these "sporadic" HCV infections are variations on the known risk factors. However, since the proportion of these cases is rather high, further attention should be on alternative and as yet unclear transmission routes.

Adolescent↗
PubMed1995

Interferon-alpha retreatment in chronic hepatitis C.

For chronic hepatitis C virus (HCV) infection, interferon-alpha (IFN-alpha) treatment has recently been established. However, the complete responding rate is not higher than 20-25%. The aim of our study was to assess IFN-alpha retreatment in chronic hepatitis C. In summary, during a second cycle of IFN-alpha, 60% of the patients responded to the retreatment. Indeed, a sustained complete response, together with long-lasting normal alanine aminotransferase values and negative serum HCV-RNA, was observed in about 40% of the retreated patients. Future prospective and controlled trials must define the optimal retreatment strategy, as well as the response-predicting factors including HCV genotypes and quantitative HCV-RNA levels.

Adult↗
PubMed1995

Hepatitis B virus superinfection in a patient with chronic hepatitis C receiving alpha-interferon treatment.

We report on a patient with chronic hepatitis C who developed acute hepatitis B during interferon alpha treatment. However, our patient promptly eliminated HBsAg and had a sustained complete response to interferon, even 6 months after the end of treatment. Acute hepatitis B superinfection in patients with chronic hepatitis C is a rarely observed event. The natural course of these patients is unknown. In our case it may be speculated that alpha-interferon treatment contributed to the prompt elimination of HBsAg from the serum.

Acute Disease↗
PubMed1995

[Re-treatment with interferon-alpha in chronic hepatitis B and C virus infection].

The efficacy of interferon-alpha retreatment was assessed in patients with chronic hepatitis B or C, not responding to a first cycle of interferon or reactivating thereafter. 27 patients with chronic hepatitis B and 25 patients with chronic hepatitis C were investigated. After an interval of at least 6 months these patients received an interferon-alpha retreatment in a higher dosage schedule and with a different interferon-alpha subtype. In patients with chronic hepatitis B a loss of serum HBV-DNA was observed in 59% patients after interferon-alpha retreatment. HBeAg seroconversion occurred in 8 of these patients. In chronic hepatitis C 32% of the patients responded completely to the second cycle of interferon-alpha treatment with a normalization of ALT associated with a loss of serum HCV-RNA. A partial response with a marked reduction of ALT was seen in 4 patients. In chronic hepatitis B and C a complete or partial response to the retreatment was closely associated with the response status after the first cycle. Thus, interferon retreatment seems to be effective in patients with chronic hepatitis B or C, especially in the subgroup of patients exhibiting a partial or complete response after the first interferon treatment.

Adult↗
PubMed1994

Indomethacin treatment in amphotericin B induced nephrogenic diabetes insipidus.

Nephrogenic diabetes insipidus (NDI) is a serious side effect of various drugs. Elevated renal prostaglandin E2 levels have been found in patients with lithium-induced NDI and have been implicated in the pathogenesis. We report the case of a patient who developed NDI following treatment with amphotericin B. Prostaglandin levels were elevated. Indomethacin had an antidiuretic effect and normalized prostaglandin levels.

Amphotericin B↗
PubMedDate not supplied

Long-term follow-up of patients with chronic hepatitis C after interferon-alpha treatment.

In this study, 72 patients with chronic hepatitis C virus (HCV) were followed prospectively for a mean period of 27 months after interferon treatment. Fifty-seven percent (20/35) of the patients with complete response, 18/20 with HCV-RNA-negative serum, had a sustained biochemical remission. Reactivation was seen in 43% of these patients after a mean follow-up of 7.3 months. A late relapse after more than 12 months of follow-up occurred in only 2/15 patients. Patients with a long-term complete response had significantly lower pretreatment serum HCV RNA levels than complete responders with relapse (106,239 vs. 345,649 mEq/ml, p = 0.0213). A delayed sustained biochemical remission was seen in 3/37 patients with partial or no response. Thus, long-term response is achieved in 32% of the patients treated with interferon, clearly associated with a suppression of serum HCV RNA. Patients with normal ALT values and undetectable levels of HCV RNA for more than 12 months of follow-up may usually be considered as sustained responders. Thus, for the first time, the pretreatment HCV RNA level in serum was identified as predictive of long-term response.

Adult↗