Fulminant hepatitis associated with hepatitis A virus superinfection in patients with chronic hepatitis C

BACKGROUND

Hepatitis A virus (HAV) infection rarely causes fulminant hepatic failure in people with no underlying liver disease. There are limited data on the course of this infection in patients with chronic hepatitis B and chronic hepatitis C.

METHODS

We prospectively followed, from June 1990 to July 1997, 595 adults with biochemical and histologic evidence of chronic hepatitis B (163 patients) or chronic hepatitis C (432 patients) who were seronegative for HAV antibodies. All were tested every four months for serum IgM and IgG antibodies to HAV.

RESULTS

Twenty-seven patients acquired HAV superinfection, 10 of whom had chronic hepatitis B and 17 of whom had chronic hepatitis C. One of the patients with chronic hepatitis B, who also had cirrhosis, had marked cholestasis (peak serum bilirubin level, 28 mg per deciliter [479 micromol per liter]); the other nine had uncomplicated courses of hepatitis A. Fulminant hepatic failure developed in seven of the patients with chronic hepatitis C, all but one of whom died. The other 10 patients with chronic hepatitis C had uncomplicated courses of hepatitis A.

CONCLUSIONS

Although most patients with chronic hepatitis B who acquired HAV infection had an uncomplicated course, patients with chronic hepatitis C had a substantial risk of fulminant hepatitis and death associated with HAV superinfection. Our data suggest that patients with chronic hepatitis C should be vaccinated against hepatitis A.

Identification of hepatitis A virus as a trigger for autoimmune chronic hepatitis type 1 in susceptible individuals

To identify factors contributing to the pathogenesis of autoimmune chronic active hepatitis (CAH) healthy relatives of 13 patients with the disorder were followed prospectively for 4 years. 58 relatives were monitored for various serological markers and for T-lymphocyte migration inhibitory activity every 2 months. 3 cases of subclinical acute hepatitis A occurred during the study. In 2 of the 3 subjects, before hepatitis A virus (HAV) infection, there was a defect in suppressor-inducer T lymphocytes specifically controlling immune responses to the asialoglycoprotein receptor, an antigen expressed on the hepatocyte surface. In these 2 subjects, specific helper T cells and antibodies to the asialoglycoprotein receptor persisted and increased after acute hepatitis A, and autoimmune CAH type 1 developed within 5 months. Thus, in susceptible individuals HAV is a trigger for autoimmune CAH.

Fulminant hepatitis on withdrawal of chemotherapy in carriers of hepatitis C virus

BACKGROUND

Fulminant hepatitis on withdrawal of chemotherapy has been described in chronic hepatitis B virus infection, but not in hepatitis C virus (HCV) infection. The relation between HCV and immune response to this virus, and disease severity, has not been examined. We present two patients with HCV who developed fulminant liver failure after chemotherapy was stopped.

PATIENTS AND FINDINGS

Two patients with chronic HCV infection and malignant lymphoma received chemotherapy (cyclophosphamide, adriamycin, vincristine, bleomycin, etoposide, and prednisolone in patient 1; doxorubicin, bleomycin, vinblastine, and dacarbazine in patient 2), on withdrawal of which both developed fulminant hepatitis. Alanine aminotransferase (ALT) concentrations were greatly raised (6030 and 3870 IU/L in patients 1 and 2, respectively), and serum HCV-RNA was low in both patients when severe disease developed (10(2) genome equivalents per mL). Patient 1 died, and necropsy showed massive liver necrosis.

INTERPRETATION

The findings suggest an immune-mediated mechanism for hepatocyte damage in HCV infection. Careful monitoring of ALT concentrations is necessary in such patients during and after chemotherapy.

Infections and thalassaemia

Infections are major complications and constitute the second most common cause of mortality and a main cause of morbidity in patients with thalassaemia, a group of genetic disorders of haemoglobin synthesis characterised by a disturbance of globin chain production. Thalassaemias are among the most common genetic disorders in the world. Predisposing factors for infections in thalassaemic patients include severe anaemia, iron overload, splenectomy, and a range of immune abnormalities. Major causative organisms of bacterial infections in thalassaemic patients are Klebsiella spp in Asia and Yersinia enterocolitica in western countries. Transfusion-associated viral infections (especially hepatitis C) can lead to liver cirrhosis and hepatocellular carcinoma. A unique and challenging infection detected in Asian patients is pythiosis, caused by a fungus-like organism, the mortality rate of which is very high. Because the prognosis for thalassaemia has much improved, with many patients surviving to the fifth decade of life in developed countries, it is mandatory to reduce mortality by recognising and presumptively treating infections in these patients as quickly as possible.

Epstein-Barr virus as a trigger for autoimmune hepatitis in susceptible individuals

During follow-up of healthy relatives of 13 patients with autoimmune hepatitis, seven cases of infectious mononucleosis due to Epstein-Barr virus (EBV) occurred. In two of these seven, before EBV infection, there was a defect in suppressor-inducer T lymphocytes specifically controlling immune responses to the asialoglycoprotein receptor, an antigen expressed on the hepatocyte surface. In these two, antibodies to this autoantigen persisted and increased after infectious mononucleosis, and autoimmune hepatitis developed within 4 months. In susceptible individuals, EBV is a trigger for autoimmune hepatitis.

Reactivation of replication of hepatitis B and C viruses after immunosuppressive therapy: an unresolved issue

The liver is susceptible to the toxic effects of many cytotoxic or immunosuppressive treatments. However, in carriers of hepatitis B virus (HBV) and, less frequently, of hepatitis C virus, liver damage due to reactivation of viral replication can occur after withdrawal of immunosuppressive drugs. These reactivations, which are associated with fulminant forms of hepatitis in up to 25% of cases, are observed both in symptom-free chronic carriers of hepatitis B surface antigen and in patients who have chronic hepatitis B or C and concurrent haematological tumours or solid neoplasms or who have received transplants. HBV-related complications may cause delays or modifications of therapy, and the chance of cure is reduced. In this review, we analyse clinical, biochemical, and serological issues in reactivation of viral replication and examine the role of immune reactions in the pathogenesis and the possible toxicity of immunosuppressive drugs. We emphasise the importance of identifying predictive markers of a clinically relevant reactivation, review difficulties in drug prevention and treatment, indicate studies that are needed to address the key clinical issues, and give practical recommendations to practising physicians and oncologists.

Infections in patients with cancer undergoing chemotherapy: aetiology, prevention, and treatment

Patients with cancer who are undergoing chemotherapy are highly susceptible, especially if neutropenic, to almost any type of bacterial or fungal infection. These infections cause substantial morbidity and mortality. Prophylactic use of antibiotics should be avoided, however, since this practice is associated with a risk of emergence of resistant bacteria and it does not lower the risk of death. However, chemoprophylaxis has a role for candidal fungal infections. Because infection in a neutropenic host can be rapidly fatal if not treated, the empirical administration of broad-spectrum intravenous antibiotics is generally indicated for these patients, and the local frequencies, susceptibility, and resistance patterns of various pathogens must be taken into account. Once therapy has been initiated, changes in antibiotic regimens during the first 5 days are useless unless the patient's clinical condition deteriorates substantially. The treatment of invasive fungal infections is particularly difficult. Many unsolved questions remain, and studies are proposed here that may shed light on these issues.

Lung infections after cancer chemotherapy

Lung infections can be severe consequences of chemotherapy-induced immune defects. Aetiological causes of infection include bacteria (most commonly Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Nocardia species), viruses (eg, respiratory syncytial virus, parainfluenza virus, influenza virus A and B, and cytomegalovirus), and fungi (eg, Aspergillus, Fusarium, and Mucorales species, and Pneumocystis jirovecii). Most infections are caused by bacteria (especially Gram negative), but viruses are being increasingly identified. Diagnosis is difficult and frequently time-consuming. Treatment can be ineffective for many patients, particularly those with fungal infection. The greatest hope for the future is the availability of more targeted anticancer drugs that have fewer side-effects on the immune system.

Antigen specific suppressor cell function in autoimmune chronic active hepatitis

An indirect migration inhibition assay has been used to show that lymphocytes from 26 of 29 patients with autoimmune chronic active hepatitis (CAH) generated T lymphocyte migration inhibitory factors (T-LIF) in the presence of liver specific protein (LSP), compared with only 1 of 21 patients with HBsAg-positive chronic liver disease and none of 19 controls. Generation of T-LIF activity in response to LSP was not observed in any of 5 patients with autoimmune thyroid disease although their T lymphocytes did generate T-LIF activity in the presence of thyroid membrane antigens. T lymphocytes from 1 patient with autoimmune liver and thyroid disease generated T-LIF activity in the presence of both LSP and thyroid membrane antigens. The generation of T-LIF activity by T cells from autoimmune CAH patients was suppressed when these cells were co-cultured in a 9:1 ratio with T cells from normal subjects and patients with HBsAg-positive chronic liver disease, but was unaffected if co-cultured with T cells from other patients with autoimmune CAH. T cells from patients with autoimmune CAH did, however, suppress the generation of T-LIF activity by T lymphocytes from patients with autoimmune thyroid disease when these cells were cultured with thyroid membrane antigens. After pretreatment with cimetidine or mitomycin-C for 30 min, T cells from normal subjects lost their ability to inhibit the generation of T-LIF activity to T lymphocytes from autoimmune CAH patients. These results are consistent with the hypothesis that there exists a defect in the specific suppressor T cell population controlling the immune response to LSP in autoimmune CAH which is unaffected by disease activity and treatment and which may be of fundamental importance in the pathogenesis of the disease.

T lymphocyte sensitization to HBcAg and T cell-mediated unresponsiveness to HBsAg in hepatitis B virus-related chronic liver disease

Using a newly developed indirect T lymphocyte migration inhibition test, cell-mediated immunity to HBsAg and HBcAg was directly and simultaneously examined in a total of 21 patients with HBsAg-positive chronic liver disease (CLD), and in seven subjects whose sera contained anti-HBs (2 previous acute hepatitis B; 4 hepatitis B vaccine recipients and 1 chronic active hepatitis). T cell sensitization to HBcAg was invariably detected in the HBsAg-positive CLD patients tested (12/12), whereas T cell sensitization to HBsAg was not present in any of the patients (0/21). In contrast, T cell sensitization to HBsAg was present in all anti-HBs-positive subjects. These results support the hypothesis that the cellular immune response to HBcAg, rather than to HBsAg, is implicated in the pathogenesis of HBsAg-positive CLD. Moreover, the observation that the addition of T cells from patients with HBsAg-positive CLD to T cells from anti-HBs positive subjects in a ratio of 1 to 9 reversed their sensitization to HBsAg, suggests that a hyperactivity of HBsAg-specific suppressor T cell population may be responsible for persistent HBs antigenemia.

Is there a role for viruses in triggering autoimmune hepatitis?

A role for viruses in autoimmune hepatitis (AH) has been repeatedly proposed but convincing evidence links only two viruses, hepatitis A and Epstein-Barr virus, to the type 1 form of the disease, and only in those rare cases where a genetic predisposition exists and the viral infection occurs at the right time, i.e. when other unknown factors are cooperating. In spite of an impressive amount of information conclusively showing molecular mimicry between cytochrome P450IID6 (the target autoantigen of autoantibodies characteristic of AH type 2) sequences and viral (hepatitis C virus, herpes simplex virus 1, cytomegalovirus, human T lymphotropic viruses 1 and 2) or bacterial (Salmonella typhimurium) antigens, no infectious agent is clearly able to induce this second form of the disease. In conclusion, the molecular mimicry theory has so far found little clinical evidence in its support and many more clinical observations are needed in order to unreveal possible links between viruses and AH.

Prospective study of cellular immunity to hepatitis-B-virus antigens from the early incubation phase of acute hepatitis B

Cellular immunity to hepatitis-B-virus (HBV) antigens was followed prospectively in five patients who were identified in the early incubation phase of acute HBV infection, between 30 and 70 days before the onset of liver damage. Cellular immunity to pre-S antigens was the first detectable immune response, appearing 30 days before the first rise in serum aminotransferases in every case. T-cell sensitisation to HBcAg followed, with IgM anti-HBc appearing 10 days later. A cellular immune response to HBsAg was the last to appear, 10 days before the onset of liver damage. These cellular immune responses are the earliest host responses to the virus infection and could be critical in initiating and directing the processes of liver damage and viral clearance.

Defensive medicine: It is time to finally slow down an epidemic

Defensive medicine is widespread and practiced the world over, with serious consequences for patients, doctors, and healthcare costs. Even students and residents are exposed to defensive medicine practices and taught to take malpractice liability into consideration when making clinical decisions. Defensive medicine is generally thought to stem from physicians' perception that they can easily be sued by patients or their relatives who seek compensation for presumed medical errors. However, in our view the growth of defensive medicine should be seen in the context of larger changes in the conception of medicine that have taken place in the last few decades, undermining the patient-physician trust, which has traditionally been the main source of professional satisfaction for physicians. These changes include the following: time directly spent with patients has been overtaken by time devoted to electronic health records and desk work; family doctors have played a progressively less central role; clinical reasoning is being replaced by guidelines and algorithms; the public at large and a number of young physicians tend to believe that medicine is a perfect science rather than an imperfect art, as it continues to be; and modern societies do not tolerate the inevitable morbidity and mortality. To finally reduce the increasing defensive behavior of doctors around the world, the decriminalization of medical errors and the assurance that they can be dealt with in civil courts or by medical organizations in all countries could help but it would not suffice. Physicians and surgeons should be allowed to spend the time they need with their patients and should give clinical reasoning the importance it deserves. The institutions should support the doctors who have experienced adverse patient events, and the media should stop reporting with excessive evidence presumed medical errors and subject physicians to "public trials" before they are eventually judged in court.

T-lymphocyte sensitization to hepatocyte antigens in autoimmune chronic active hepatitis and primary biliary cirrhosis. Evidence for different underlying mechanisms and different antigenic determinants as targets

Cultured with a liver-derived lipoprotein complex, T lymphocytes from 42 of 45 patients with autoimmune chronic active hepatitis generated migration inhibitory factor compared with 16 of 33 patients with primary biliary cirrhosis. Unlike T lymphocytes from patients with primary biliary cirrhosis, the T-cell reactivity of patients with chronic active hepatitis was always suppressed by T cells from normal subjects and, with two exceptions, by T cells from patients with primary biliary cirrhosis, even when these latter cells exhibited sensitization to this same antigen complex. Using a component of the whole complex, the asialoglycoprotein receptor as antigen, migration inhibitory factor was invariably released by T cells from patients with autoimmune chronic active hepatitis, but from only 2 of 8 patients with primary biliary cirrhosis sensitized to the whole complex. Thus, in autoimmune chronic active hepatitis, but not in primary biliary cirrhosis, the asialoglycoprotein receptor is invariably a target for cellular immune reactions and is associated with a suppressor T-cell defect for hepatocyte antigens.

Pneumocystis carinii pneumonia during primary HIV-1 infection

3 patients with severe CD4 lymphocytopenia (62-91 cells/microL) and inverted CD4/CD8 ratios (0.13-0.15) developed Pneumocystis carinii pneumonia during symptomatic, primary HIV-1 infection. Within four months of symptom onset, their CD4 counts and CD4/CD8 ratios returned to normal. Twenty-nine to forty-eight months after acquiring HIV-1 infection, they show no signs or symptoms of progression to AIDS. Pneumocystis carinii pneumonia can occur, therefore, in primary HIV-1 infection, and profound CD4 lymphocytopenia can revert to normal without antiretroviral therapy.

Fulminant hepatitis associated with hepatitis A virus superinfection in patients with chronic hepatitis C

There have been conflicting reports of the clinical outcome of acute hepatitis A virus (HAV) infection in patients with chronic hepatitis C virus (HCV) infection. A prospective study evaluated 432 patients with chronic hepatitis C (183 with cirrhosis) over a 7-year period. Of the 17 patients with concurrent HAV infection, seven developed fulminant hepatitis and six died. None of these patients had cirrhosis; however, the HLA phenotype (A1; B8:DR3) appeared to be a significant factor in the development of fulminant hepatitis. Patients with this phenotype had high titres of antinuclear antibodies, antismooth muscle antibodies and antiasialoglycoprotein-receptor antibodies, possibly reflecting the induction of autoimmune hepatitis in this group. The high frequency of fulminant hepatitis in patients with HAV/HCV coinfection contrasts with other surveys, although a large Centers for Disease Control and Prevention (CDC) survey demonstrated that HAV infection in patients with pre-existing chronic liver disease (CLD) is associated with increased mortality. It is likely that CLD has some importance as an underlying factor in the development of fulminant hepatitis following HAV infection. Further prospective studies are needed to clarify this issue.

T-cell inducers of suppressor lymphocytes control liver-directed autoreactivity

The sensitisation of helper T cells of patients with autoimmune chronic active hepatitis to a liver-cell membrane-expressed asialoglycoprotein receptor protein is shown to be associated with a defect of T cells that specifically induce suppressor lymphocytes. These lymphocytes are found in an activated state in the peripheral blood of healthy people and may form part of an immunoregulatory network which actively prevents autoimmunity.