High prevalence of serum cryoglobulins in multitransfused hemophilic patients with chronic hepatitis C

The prevalence, clinical relevance, and risk factors of serum cryoglobulins in hemophilic patients with chronic hepatitis C virus (HCV) infection are unknown. We studied 135 consecutive hemophilic patients (median age, 31 years; range, 10 to 69 years) with chronic hepatitis C, exposed to the virus for 10 to 41 years. A total of 67 patients were coinfected with the human immunodeficiency virus (HIV), and 3 (2%) had signs of cirrhosis. Serum samples were tested for the presence of cryoglobulins, hepatitis B virus (HBV) markers, including HBV-DNA by hybridization assay, and antibody to HCV by enzyme immunoassay (EIA). Serum HCV-RNA was tested by polymerase chain reaction and typed with a hybridization technique. Samples were also tested for antitissue antibodies, immunoglobulins, rheumatoid factor, and C3 and C4 proteins of complement. Forty-two hemophiliacs (31%) circulated cryoglobulins (median levels, 166 mg/L; range, 66 to 480) predominantly type III (62%; and 29% type II). None of the patients had clinical signs or symptoms of systemic vasculitis. Cryoglobulinemic patients had more often serum HCV-RNA (95% v 80%, P < .05), rheumatoid factor (20% v 6%, P < .05), higher levels of IgG (2,354 +/- 682 mg/dL v 1,928 +/- 557 mg/dL, P < .0005) and IgM (323 +/- 226 mg/dL v 244 +/- 243 mg/dL, P < .05), and lower levels of serum C4 (19 +/- 8 mg/dL v 24 +/- 8 mg/dL, P < .05) than patients without cryoglobulins. The risk of producing cryoglobulins was greater for 114 patients circulating HCV-RNA than for 21 nonviremic patients (odds ratio [OR] = 4.9, 95% confidence interval [CI] = 1.1 to 22.0) and for the 31 patients with longer exposure to HCV (more than 26 years) than for the 24 patients with shorter (17 years or less) exposure (OR = 4.4 95% CI = 1.1 to 18.0). In conclusion a large number of multitransfused hemophiliacs with chronic HCV infection circulated serum cryoglobulins but none had clinical signs or symptoms of vasculitis. The risk of developing cryoglobulins parallels the duration of exposure to HCV.     

Identification of HLA-A3 and -B7-restricted CTL response to hepatitis C virus in patients with acute and chronic hepatitis C

We investigated the role of the two highly conserved cysteine residues, cysteines 67 and 95, of the human immunodeficiency virus type 1 (HIV-1) protease in regulating the activity of that protease during viral maturation. To this end, we generated four HIV-1 molecular clones: the wild type, containing both cysteine residues; a protease mutant in which the cysteine at position 67 was replaced by an alanine (C67A); a C95A protease mutant; and a double mutant (C67A C95A). When immature virions were produced in the presence of an HIV-1 protease inhibitor, KNI-272, and the inhibitor was later removed, limited polyprotein processing was observed for wild-type virion preparations over a 20-h period. Treatment of immature wild-type virions with the reducing agent dithiothreitol considerably improved the rate and extent of Gag processing, suggesting that the protease is, in part, reversibly inactivated by oxidation of the cysteine residues. In support of this, C67A C95A virions processed Gag up to fivefold faster than wild-type virions in the absence of a reducing agent. Furthermore, oxidizing agents, such as H2O2 and diamide, inhibited Gag processing of wild-type virions, and this effect was dependent on the presence of cysteine 95. Electron microscopy revealed that a greater percentage of double-mutant virions than wild-type virions developed a mature-like morphology on removal of the inhibitor. These studies provide evidence that under normal culture conditions the cysteines of the HIV-1 protease are susceptible to oxidation during viral maturation, thus preventing immature virions from undergoing complete processing following their release. This is consistent with the cysteines being involved in the regulation of viral maturation in cells under oxidative stress.     

Patterns and prevalence of hepatitis C virus infection in posttransfusion non-A, non-B hepatitis

Improved serologic and polymerase chain reaction (PCR)-based tests for hepatitis C virus (HCV) infection provided an opportunity to reexamine a posttransfusion follow-up study done from 1969 to 1972. A total of 213 cardiac surgery patients was prospectively followed after receiving an average of 18 units of blood, 24% of which was from paid donors. Serial sera were tested for antibody to recombinant DNA-derived C100-3 and capsid polypeptides; selected cases were also tested against synthetic peptides derived from different regions of the HCV sequence. PCR and RIBA II immunoblot assays were done on selected sera. Each of 55 probable and 5 of 11 possible hepatitis cases who were seronegative before transfusion seroconverted. Anti-HCV seroconversion also occurred in 6 (4%) of 148 subjects without hepatitis. Among subjects followed > 1 year, PCR positivity persisted in 14 (82%) of 17. If the results of this study can be generalized, all bloodborne non-A, non-B hepatitis may be due to HCV.     

Immunoglobulin M antibody response to hepatitis C virus core protein in patients with chronic hepatitis C

We retrospectively assessed the frequency and clinicopathologic and virologic significance of production of immunoglobulin M (IgM) antibody to hepatitis C virus (HCV) core protein in patients with chronic hepatitis C. Sera from 60 patients with chronic hepatitis C were tested for IgM anti-HCVcore (anti-HCc). Twenty of these patients received ribavirin plus interferon-alpha for 24 weeks, and were classified as sustained, transient, or nonresponders on the basis of alanine aminotransferase levels and the presence of HCV RNA at the end of treatment and 24 weeks later. IgM anti-HCc was detected in 21 patients. There was no correlation between the presence of IgM anti-HCc and clinical features such as sex, age, mode of transmission, serum levels of alanine aminotransferase, HCV genotype, serum HCV titer, or histologic findings. Among the patients who received ribavirin plus interferon-alpha, the mean IgM anti-HCc level before therapy was comparable between sustained (n = 10), transient (n = 8), and nonresponders (n = 2). A statistically significant decrease in IgM anti-HCc response during antiviral therapy was observed in the 18 responders who became negative for serum HCV RNA at the end of therapy. These data suggest that IgM anti-HCc is of limited clinical usefulness as a marker of chronic HCV infection. Serial testing for IgM anti-HCc may provide a marker of antiviral response.     

Acute bacterial meningitis in children admitted to the Queen Elizabeth Central Hospital, Blantyre, Malawi in 1996-97

To design appropriate interventions, we collected clinical and demographic data prospectively on all children aged one day to 14 years admitted with a diagnosis of bacterial meningitis (BM) from April 1st 1996 to March 31st 1997 to the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi. During the study period 267 children (2.7% of all paediatric admissions) were found to have BM; 83% were under 5 years of age, 61% under one year and 23% under one month. The most common causative organisms in the post neonatal period (n=206) were Streptococcus pneumoniae (27%), Haemophilus influenzae type b (Hib) 21%, and Salmonella typhimurium (6%). In the neonatal group (< 1 month, n=61) the most common causes were Streptococcus agalactiae (23%), S. typhimurium (15%), S. pneumoniae (11.5%) and other Gram negative rods (11.5%). Nineteen of 21 salmonella infections were in children under one year of age and all S. agalactiae were in infants under three months. There was delay on presentation: the average length of fever was 4.6 days, 39.5% had convulsed prior to arrival and 57% had an altered level of consciousness. An initial diagnosis of malaria had probably contributed to the delay in 22.5% (42 of 186 tested). 48% were < 80% weight for age, with 18% < 60%) weight for age. The overall mortality was 40%. The outcome was worst in salmonella infections, particularly neonatal salmonella BM with a case fatality rate (CFR) of 89% (8 of 9 cases). Coma on presentation worsened prognosis (mortality 64% if Blantyre Coma Score < 3, 26% if > 3). 15% of survivors had sequelae on discharge. 20% of Hib isolates were resistant to chloramphenicol, but all salmonellae were sensitive. 5% of S. pneumoniae were resistant to penicillin and 8% to chloramphenicol. Earlier access to adequate health care and awareness of BM in a malaria-endemic area would reduce mortality and morbidity. Vaccination against Hib infection would have reduced death by 18 (17%) and prevented sequelae in 7 cases.     

Prevalence of antibodies to hepatitis C virus among family members of patients with chronic hepatitis C

In this study, 108 family members of 40 chronically HCV-infected patients (19 post-transfusion and 21 sporadic), and 45 families of 16 anti-HCV-negative index cases (control group) were tested for anti-HCV antibodies. Anti-HCV antibodies were found in 16 (14.8%) families of anti-HCV-positive index cases (15% males and 14.6% females; p = NS), with no difference between families of index cases with post-transfusion and those with sporadic HCV infection. Out of the 16 anti-HCV positive family members, 12 (75%) had clinical and/or serological evidence of chronic liver damage. None of the control group subjects were anti-HCV-positive (p < 0.01). The rate of anti-HCV positivity was 34.4% among spouses, 14.3% among siblings, 16.7% among cohabitants and 2.3% among children; anti-HCV antibodies were not detected among parents. We found a positive correlation between the prevalence of anti-HCV antibodies among families and the severity of the HCV-related chronic liver damage of the index cases (p < 0.00005). In addition, to confirm that HCV infection and HCV-related chronic hepatitis may be transmitted intrafamiliarly, our findings also indicate that horizontal, especially sexual contact, is a more important route of HCV infection than vertical/perinatal transmission. Finally, the risk of acquiring HCV infection among families appears to be the highest when index cases are suffering from severe HCV-related chronic hepatitis.     

Cellular immunity to hepatitis C virus core protein and the response to interferon in patients with chronic hepatitis C

To investigate the involvement of T-cell response against hepatitis C virus (HCV) antigens in viral clearance after interferon therapy, we measured interleukin-2 (IL-2) production by peripheral mononuclear cells in response to HCV core in patients with chronic hepatitis C. In a cohort of 43 patients, we investigated the frequency of circulating core-specific T-helper (Th) cell precursors by the limiting-dilution assay, and in a second cohort of 60 patients, we analyzed the response to specific core epitopes using 52 synthetic 15-mer overlapping peptides. We observed that the frequency of core-specific Th cell precursors was significantly higher in patients with sustained biochemical and virological response (SR) after interferon (IFN) therapy (median, 1/55,736) than in untreated patients (1/274,023) or that in patients who remained viremic after completion of the treatment-nonresponders (NR) plus transient responders (TR) (1/1,909,972). Patients who failed to respond to IFN (NR) and those who relapsed after IFN discontinuation (TR) had a similarly low number of precursors. The number of core peptides recognized by SR, TR, NR, UT, and healthy controls was 8.2 +/- 1.5, 6.5 +/- 1.2, 2.0 +/- 0.5, 2.7 +/- 0.9, and 0.3 +/- 0.2, respectively. In SR, the intensity of the proliferative response to core peptides as estimated by the summation of stimulation indexes (sigmaSI) was significantly higher than in NR and than in UT, but not different from that of TR. Our results indicate that both expansion of HCV-specific Th cell precursors and Th cell recognition of multiple core epitopes seem to be important in the elimination of HCV after IFN therapy.     

Effects of interferon-alpha on serum hepatitis C virus in patients with chronic hepatitis C

Interferon is beneficial in some patients with chronic hepatitis C. To assess the efficacy of interferon, we used the polymerase chain reaction (PCR) to measure HCV RNA in serial serum samples from 13 chronic hepatitis C patients who were treated with interferon-alpha. Serum alanine aminotransferase (ALT) values normalized in association with the disappearance of serum HCV RNA in nine cases during the therapy. Serum HCV remained negative after the therapy in the three patients who had no relapse, while serum HCV RNA reappeared in the six patients with elevation of ALT values. The persistence of normal ALT levels appears to be correlated with the clearance of the serum HCV. There were two patients whose ALT became normal immediately after the cessation of interferon. Serum HCV was detectable at the end of treatment when serum ALT was elevated, and thereafter serum HCV disappeared. This result suggests an immunomodulatory effect of interferon in the clearance of HCV in some cases. Furthermore, the semiquantitative PCR assay showed that all five patients in whom ALT values were normal at the end of follow-up without detectable serum HCV genome had lower HCV titers in the pretreatment sera than the other eight patients. The detection of HCV RNA by the PCR assay is useful in determining the efficacy of interferon and its mechanisms.     

Low prevalence of antibody to hepatitis C virus in an urban adolescent population

We tested 869 subjects attending either an urban adolescent medicine clinic or a school-based clinic for antibody to hepatitis C virus. Demographic data indicated a representative study sample, and behaviors associated with hepatitis C virus transmission. One subject (0.1%) was seropositive for antibody to hepatitis C virus, indicating a very low prevalence of hepatitis C virus exposure in adolescents.     

Responsiveness to interferon alpha treatment in patients with chronic hepatitis C coinfected with hepatitis G virus

BACKGROUND/AIMS: Patients with chronic hepatitis C are often coinfected with the new identified Flaviviridae-like agent, termed hepatitis G virus (HGV). The aim of the study was to investigate the responsiveness of hepatitis G virus to interferon alpha and to evaluate whether a hepatitis G virus coinfection negatively influences the outcome of treatment in chronic hepatitis C. METHODS: One hundred and fifteen patients with histologically proven chronic hepatitis C were treated with interferon alpha and investigated for the presence of hepatitis G virus coinfection by nested polymerase chain reaction with primers from the helicase region of hepatitis G virus. All patients received at least 3 MU (range 3-6) interferon alpha thrice weekly for at least 6 months (mean 8, range 6-12). Polymerase chain reaction products of seven pre- and post-treatment hepatitis G virus positive patients were directly sequenced for identification of sequence variability during the follow-up. RESULTS: Eighteen (16%) patients were coinfected with hepatitis G virus. Although nine (50%) of these patients became HGV RNA negative during interferon alpha therapy, only three patients (17%) remained HGV RNA negative at the end of follow-up (mean 24 months). The rate of sustained response of chronic hepatitis C was not significantly different between patients with hepatitis C virus infection and HCV/HGV coinfection (19% vs 28%). Severity of liver disease as determined by alanine aminotransferase levels, histology and hepatitis C virus viremia was not significantly different in patients with hepatitis C virus or HCV/HGV coinfection. Sequence analysis of the helicase region revealed that our isolates all belonged to the hepatitis G virus and not to the GBV-C like genotype. No amino acid exchanges during the observation period of up to 48 months were observed, indicating that this region is highly conserved. CONCLUSIONS: The responsiveness of hepatitis G virus to interferon alpha in chronic HCV/HGV coinfected patients is similar to that observed in chronic hepatitis C. Hepatitis G virus coinfection seems not to interfere with the efficacy of interferon alpha treatment in patients with chronic hepatitis C.     

The effect of HLA alleles on response to interferon therapy in patients with chronic hepatitis C

The objective of this study was to determine the degree of leukocyte activation, as measured by cytokine release, in circulating blood during experimental extracorporeal circulation. Complete in vitro extracorporeal membrane oxygenation (ECMO) circuits were used, and 9 experiments were performed. Whole blood stored at 37 degrees C was used as the control. Blood samples were withdrawn before the start of perfusion and at 24 h of perfusion. Statistically significant releases of interleukin (IL)-1beta, IL-8, and IL-1 receptor antagonist were observed in the perfusion circuits compared to both the control blood and baseline values. Also, increases in plasma tumor necrosis factor (TNF)alpha and IL-6 were seen after 24 h of perfusion although these changes did not reach statistical significance. These results indicate that extracorporeal circulation induced leukocyte activation and cytokine release. These reactions might, as an additional trauma, deteriorate the situation in an already severely ill patient. A search for methods to counteract this untoward activation seems warranted.     

Detectable levels of IgM antibodies to hepatitis C virus core protein predict breakthrough in patients with chronic hepatitis C treated with interferon-alpha

The predictive value of IgM antibodies to hepatitis C virus core antigen (HCcAb) is controversial. We studied 79 patients undergoing interferon-alpha (IFN-alpha) treatment and we found that detectable levels of IgM HCcAb could predict breakthrough on treatment.     

The role of hepatitis C virus specific CD4+ T lymphocytes in acute and chronic hepatitis C

Since the discovery of hepatitis C virus it has become clear that chronic hepatitis C is a major health problem throughout the world. Because antiviral agents are of limited value in the treatment of chronic hepatitis C, research has focused on the antiviral immune response for the development of both a protective vaccine and effective immunotherapies for established chronic infection. Antiviral antibodies are present in almost all patients with chronic hepatitis C but do not seem to be virus neutralizing, probably due to the high mutational rate of viral envelope proteins. Studies on the antiviral T cell response have revealed the presence of virus-specific CD4+ helper and CD8+ cytotoxic T cells in a substantial proportion of patients with chronic hepatitis C. Recent studies describe an association between strong CD4+ T helper cell activity to certain hepatitis C virus antigens and a self-limited course of acute hepatitis C and possibly also a sustained response to treatment with interferon-alpha. Therapeutic manipulation of the virus-specific T cell response may thus develop into a new approach for prevention and treatment of hepatitis C virus infection.     

Profile and cost of head injury patients admitted to the Waikato Hospital Intensive Care Unit

AIMS: To examine the profile and hospital costs of head injury patients admitted to the Waikato Hospital Intensive Care Unit (ICU). METHODS: Data were collected on head injury patients admitted to ICU over 41 months and costs of head injury patients in ICU, the High Dependency Unit (HDU) and other wards were calculated. RESULTS: There were 286 head injury patients admitted to ICU, of whom 62% had a Glasgow Coma Score < or = 8. Times in the ICU and hospital were 1760 and 7352 days respectively. Costs per day were $2280 in ICU, $800 in HDU and $500 in other wards. The cost for ICU was $1,174,478 per year, and for the total hospital treatment, $2.05 million (83 head injury patients) per year. Admissions of head injury patients to all New Zealand ICUs were 777 over the year to June 1996. Thus, assuming similar costs to the Waikato Hospital, New Zealand hospitals spend each year approximately 10.9 million dollars on head injury patients in ICUs and 19 million dollars on overall hospital stays (including ICU). In a selected group of 123 severe head injury patients, the six month Glasgow Outcome Scores showed that 36% were in the moderate to severe disability categories and likely to cause major ongoing ACC costs. The costs of the 80% of head injury patients admitted to hospital but not admitted to ICU, and their prehospital and postdischarge costs were not studied. CONCLUSIONS: The New Zealand epidemic of head injuries continues to consume large amounts of the health money and produce major social costs.