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C Tibbs

Publications and source records attributed to C Tibbs.

9 recordsLinked to original sources
PubMed1996

Evidence that the HLA DQA1*03 allele confers protection from chronic HCV-infection in Northern European Caucasoids.

In the search for factors which may influence susceptibility to and outcome from chronic hepatitis C virus (HCV) infection, few studies have considered the influence of host genes. In the present investigation we have performed HLA DRB1, DQA1, DQB1, and DPB1 genotyping on 104 northern European patients with chronic HCV infection and 177 racially and geographically matched controls. Three HLA class II alleles, DRB1*0403, DQA1*03, and DQB1*0302 were present at a significantly lower frequency in patients compared with controls (4.9% vs. 13%, 20.7% vs. 41.2%, and 11.4% vs. 30.5%, respectively) though only two DQB1*0302 and DQA1*03 were significant after correction for multiple testing (pc = 0.038, and pc = 0.046, respectively). No further HLA associations with chronic HCV infection were observed and there was no correlation between stage of disease and HLA genotype. These data provide the first suggestion that susceptibility to chronic HCV infection may be influenced by the hosts' HLA DQ alleles.

Alleles↗
PubMed1996

Liver function tests in adults with Plasmodium falciparum infection.

This study examines the levels of serum bilirubin, aspartate transaminase and alkaline phosphatase in adults with Plasmodium falciparum malaria. One hundred and six sets of liver function tests were obtained, and 63 (59.4%) patients had one of the above indices elevated outside the local reference range. Serum bilirubin and aspartate transaminase were relatively higher than alkaline phosphatase. Neither duration of illness nor severity of infection showed any significant correlation with any of the indices measured.

Adolescent↗
PubMed1995

Effects of ribavirin on intrahepatic and extrahepatic expression of hepatitis C virus in interferon nonresponsive patients.

Response to ribavirin therapy (1,000-1,200 mg/day for 6 months) was evaluated in nine patients with chronic hepatitis C virus (HCV) infections who had previously failed to respond to a 6-month course of alpha-interferon. All had chronic active hepatitis with elevated serum aminotransferase activities (mean +/- SD = 138 +/- 66IU/I). During ribavirin therapy, three showed a complete response (normalized serum aminotransferase), although in one patient this returned to the pretreatment level 2 months after treatment was stopped. Three others showed a partial response (serum aminotransferase reduction by > or = 50%) and the remainder showed no response. There were no consistent changes in HCV-RNA (positive strand) in serum, liver, or peripheral blood mononuclear cells during therapy, but two patients lost HCV-RNA from serum and three of five patients with negative strand HCV-RNA in their livers lost this putative replicative form of the virus. The findings suggest that ribavirin may exert its effects by suppressing viral replication rather than by eradicating the virus, at least in this group of patients, and that the drug may have some benefit in selected cases of chronic hepatitis C that are resistant to interferon. However, peripheral blood mononuclear cells represent a major extrahepatic reservoir of HCV and the present regimen of ribavirin therapy did not significantly affect this situation. More prolonged therapy may be required to eradicate the virus from this large pool of cells with the potential to continually reinfect the liver.

Adult↗
PubMed1995

Viral causes and management of acute liver failure.

Infection with an identified hepatotrophic virus accounts for 13-50% of acute liver failure (ALF) in Europe, and an additional 16-17% of cases have non-A non-B or indeterminate hepatitis in whom a viral aetiology is presumed. Hepatitis C is rarely responsible for acute liver failure in Europe and North America but accounts for a higher proportion of cases in Japan, and hepatitis E may lead to ALF, particularly in pregnant women. The survival in cases of acute liver failure associated with hepatitis A is 70%, whereas less than 30% of those with non-A non-B hepatitis survive without a transplant. Management depends on intensive care support and careful selection of patients likely to benefit from transplantation. Recurrence of hepatitis A and non-A non-B hepatitis has been reported following transplantation for ALF, and hepatitis B recurs less frequently in these circumstances than after transplantation for chronic infection.

Humans↗
PubMed1994

Community prevalence of hepatitis C viraemia: a polymerase chain reaction study.

In order to estimate the prevalence of HCV carriage in an inner city health district, we undertook a polymerase chain reaction (PCR) based survey of sera collected from 1,0002 patients attending general practitioners for reasons unrelated to liver disease. The series comprised 305 sample selected sera patients sample from sera 995 patients previously screened by C100 antigen-based anti-HCV tests. Overall, 7 patients were positive for HCV RNA. Four cases had anti-C100 antibodies to HCV, 2 were strictly negative but had high-normal/borderline optical densities by ELISA assay, while one was completely anti-HCV negative. All but one had normal liver function tests. Only 3/7 PCR positive cases had any serum marker for hepatitis B (HBV) exposure (2 HBsAg positive, 1 IgM anti-HBc positive). The minimum point prevalence of HCV carriage in this community is 0.7%, approximating the HBsAg carriage in the same population (1%). HCV carriage in this inner city population is considerably higher than would be predicted by blood donor surveys. A positive anti-HCV anti-body (anti-C100) test is poorly predictive (approximately 10%) of HCV RNA carriage in a general practice based population in which measurement of "surrogate" (HBV related) HCV markers would have detected only 3/7 cases of presumed chronic HCV carriage.

Adult↗
PubMed1994

Hepatitis C and E in non-A non-B fulminant hepatic failure: a polymerase chain reaction and serological study.

A significant proportion of patients with fulminant hepatic failure have clinical, biochemical and histological features suggestive of acute viral hepatitis, without serological evidence of either hepatitis A or B. The contribution of hepatitis C to such cases of non-A non-B fulminant hepatic failure is presently uncertain while hepatitis E is well recognized as a cause of fulminant hepatic failure in endemic areas. Nested polymerase chain reaction for detection of both hepatitis C and E virus as well as two serological assays for anti-hepatitis C virus and anti-hepatitis E virus western blotting (both IgG and IgM) were performed on acute sera of 42 consecutive cases of non A, non B-fulminant hepatic failure and on convalescent sera of 17 of 20 patients who underwent orthotopic liver transplantation. Fresh liver tissue, obtained at the time of transplantation, was also studied by polymerase chain reaction in eight cases. Evidence of an acute hepatitis E virus infection (hepatitis E virus RNA amplified from serum by polymerase chain reaction or serum IgM positive to western blot) was found in eight patients. One patient had anti-HCV at presentation but assays on later sera proved negative. Convalescent sera and sera obtained after orthotopic liver transplantation were all negative to both anti-HCV assay systems, but HCV RNA was not found in either serum or liver tissue in any case.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Absence of hepatitis C virus in British patients with type 1 autoimmune chronic active hepatitis--a polymerase chain reaction and serological study.

Despite several studies from continental Europe reporting a high prevalence of antibodies to the hepatitis C virus (HCV), there has been little evidence of such infection in patients from the United Kingdom. The use of the polymerase chain reaction combined with two separate second generation anti-HCV assays is reported here in 58 UK patients with well-documented autoimmune chronic active hepatitis. All patients were in corticosteroid induced remission. All sera were collected prospectively for the specific purpose of this study. HCV-RNA was not detected by use of the polymerase chain reaction in any of the patients and antibodies to HCV were only detected in one patient. No evidence was found for the involvement of the hepatitis C virus in UK patients with classical, corticosteroid sensitive autoimmune chronic active hepatitis.

Adult↗
PubMed1992

Prevalence of antibodies to hepatitis C in dialysis patients and transplant recipients with possible routes of transmission.

The prevalence of hepatitis C infection and possible predisposing factors was assessed in a renal unit. Of 343 patients at our renal dialysis centre, 37 (10.8%) were anti-HCV positive by a 1st-generation assay (ELISA, Ortho/Chiron) and confirmed positive in 35 (10.2%) with a 2nd-generation test (UBI, New York). Anti-HCV positivity was significantly associated with: duration of renal replacement therapy (P < 0.0001); quantity of blood transfused (P < 0.002); duration of hospital haemodialysis (P = 0.0001); duration with a functional renal transplant (P = 0.039); and aspartate aminotransferase (P < 0.0001). Logistic regression determined the following variables to be independent risk factors: duration of renal replacement therapy with a relative risk of 34.3 for 5-9 years and 87.4 when the duration was in excess of 10 years; renal transplant for less than 1 year (relative risk of 5.0); transfusion in excess of 50 units of blood (relative risk of 11.6). Clinical assessment of anti-HCV-positive patients revealed peripheral signs of chronic liver disease in 40%, hepatomegaly in 34%, and splenomegaly in 9%. This prevalence of hepatitis C infection is similar to other European and North American centres, but contrasts with low prevalence rates reported from dialysis populations in the UK. It adds further support for routine screening of blood and possibly organ donors and implementation of further infection control measures in dialysis centres.

Adult↗