Hepatitis C virus genotypes and liver disease in patients undergoing allogeneic bone marrow transplantation

How I treat sinusoidal obstruction syndrome

Sinusoidal obstruction syndrome (SOS), previously called veno-occlusive disease (VOD) can be a difficult problem after hematopoietic cell transplantation (HCT). The overall incidence has changed since the early days of allogeneic HCT. Prophylaxis and treatment remain important components of supportive care. As the indication and the comorbidities for HCT continue to change, especially with older and more infirm patients, SOS remains an important area for clinicians. I discuss how SOS could be addressed, from prophylaxis to diagnosis and potential therapy.

Hepatitis B and C in hematopoietic stem cell transplant

Although the risk of acquisition of hepatitis B or hepatitis C virus through blood products has considerably reduced since the last decade, some infected patients are candidates to stem cell transplantation. Others may have no alternative than an infected donor. In all these cases, recipients of transplant are prone to short and long term liver complications. The evolution of liver tests under chemotherapy before transplant may give useful information to anticipate on the risk of hepatitis reactivation after transplant, both for HBv and HCv. More than sixty percent of the patients who are HBsAg-positive before transplant reactivate after transplant, and 3% develop acute severe liver failure. Because both viral replication and immune reconstitution are the key factors for reactivation, it is crucial to closely follow liver function tests and viral load during the first months of transplant, and to pay a special attention in slowly tapering the immunosuppression in these patients. Lamivudine reduces HBv viremia, but favors the emergence of HBv polymerase gene mutants and should be individually discussed. Both in case of HBv or HCv hepatitis reactivation with ALT ≥ 10N concomitantly to an increase in viral load at time of immune reconstitution, steroids should be given. In case there is no alternative than a HBv or HCv positive geno-identical donor, the risk of viral hepatitis, including acute liver failure and late complications, should be balanced with the benefit of transplant in a given situation.

Infectious complications of acute and chronic GVHD

Immune defects prolonged by treatment regimens for graft-versus-host disease (GVHD) include cell-mediated immunity and hypogammaglobulinemia. Infections have become increasingly important during GVHD therapy, paradoxically because the success of immunosuppressive practice has led to improved survival. Infections originate from both endogenous and exogenous sources. Regimens for prevention of infection include: (a) continued surveillance monitoring for infections with reliable diagnostic testing, and (b) antimicrobial prophylaxis for those pathogens without markers that could be followed for surveillance. Repeated episodes of the same infection, diagnosis of a new life-threatening infection, or specific underlying hematologic diagnoses should prompt a look for gross immunoglobulin deficiency that could be corrected in the short term by immunoglobulin therapy. At times, measurement of CD4+ lymphocyte counts will assist in determining whether augmented prophylaxis is warranted. Since their efficacy may be limited, vaccine injections are not given during the immunosuppression associated with GVHD therapy, with the exception of influenza.

Monitoring serum hepatitis C virus (HCV) RNA in patients with HCV-infected CD20-positive B-cell lymphoma undergoing rituximab combination chemotherapy

Several studies have shown that the frequency of hepatitis C virus (HCV) infection is high in patients with B-cell non-Hodgkin's lymphoma (NHL). In these studies, liver dysfunction during chemotherapy has been demonstrated, but changes in HCV ribonucleic acid (RNA) levels during chemotherapy have not been well documented. In this study, we monitored serum HCV RNA levels and liver function in five HCV-infected patients with B-cell NHL undergoing treatment with rituximab-combination chemotherapy. Increased HCV RNA levels during or after the chemotherapy were observed in all five patients, and a significant increase in transaminases was seen in one case. In this case, serum HCV RNA level dramatically decreased at the time of the increase of transaminases, and this suggested that the cause of liver damage was an immune reaction against hepatocytes with HCV and not any anticancer drug induced liver toxicity. Monitoring of serum HCV RNA levels and transaminases may be helpful to understand the cause of liver dysfunction in patients receiving chemotherapy. However, increases of HCV viral load were not associated with the occurrence of liver dysfunction in this study. Further studies will be necessary to investigate more fully the relationship between changes in HCV viral load and liver function during chemotherapy for HCV-infected patients.

Hepatitis C virus infection in special groups

Hepatitis C virus (HCV) infection is associated with a wide spectrum of clinical manifestations which may influence the choice of diagnostic assays, especially in haemodialysis patients, the clinical course of infection with possible multiple and sequential episodes of hepatitis in multiple transfused patients, and the severity of liver disease, especially in patients with HBV-HCV co-infection. The consequences of HCV infection in patients with organ graft are not completely understood due to the complexity of the clinical situations and the unavailability of long-term follow-up. Furthermore, current antiviral therapy is not very effective in these populations. Thus, it is especially important to protect patients at risk for HCV infection, using universal precautionary procedures.

Hepatitis C virus infection and bone marrow transplantation: a cohort study with 10-year follow-up

Before the introduction of routine blood donor screening in 1991, marrow transplant recipients were at significant transfusion-associated risk for infection with hepatitis C virus (HCV). We followed a cohort of 355 patients undergoing transplant in Seattle during 1987 to 1988 to determine (1) the impact of pretransplant HCV infection on the occurrence and severity of venocclusive disease (VOD); (2) the impact of HCV infection on liver dysfunction, other than VOD, occurring between 21 and 60 days after transplantation; and (3) the natural history of post-transplant HCV liver disease with a 10-year follow-up. HCV-RNA status was determined on serum stored before transplant and at day 100 post-transplant. Sixty-two (17%) patients were HCV-RNA positive before transplant, and 113 (32%) were HCV-RNA positive by day 100 post-transplant (or before death). Severe VOD developed in 22 of 46 (48%) evaluable patients with pretransplant HCV infection and in 150 of 229 (14%) evaluable patients without HCV (P <.0001). In multivariable analysis of risk factors for developing VOD, pretransplant HCV infection associated with elevated serum aspartate transaminase (AST) levels predicted the development of severe VOD (relative risk, 9.6; P =.0001). The presence of HCV with normal AST levels before transplant was not a risk factor for severe VOD. Between 21 and 60 days after transplant, HCV-RNA positive-patients had higher AST levels (median 101 U/L), but similar alkaline phosphatase and total bilirubin levels compared with HCV-negative patients, suggesting that cholestatic liver disease (particularly graft-versus-host disease [GVHD]) was not related to HCV infection. An acute flare of hepatitis (AST >10 times the upper limit of normal) developed at a mean of 136 +/- 58 days in 31% of HCV-positive patients; no patients developed fulminant hepatitis. Between 5 and 10 years after transplant, 57% of HCV-positive and 6% of HCV-negative patients had mild to moderate elevations of AST (P <. 0001), but HCV infection was not associated with excess mortality between 3 and 10 years after bone marrow transplantation. In summary, HCV infection with elevated AST levels is a significant risk factor for severe VOD after marrow transplant. However, the decision to proceed to transplantation in HCV-positive patients must balance the absolute risk of death from VOD against the risks of the underlying disease. In long-term survivors, HCV infection is not associated with excess mortality over 10 years of follow-up.