Lamivudine therapy for chronic hepatitis B in renal transplant recipients

The therapeutic response of antiviral therapy in HBsAg-positive renal transplant recipients and a long-term follow-up

BACKGROUND

Early prediction of lamivudine (LAM) response by individualized monitoring of serum HBV DNA like roadmap concept, and investigation of the outcome after LAM discontinuation in renal transplant recipients (RTRs) with chronic hepatitis B (CHB).

METHODS

We conducted a study on 19 RTRs with HBV infection receiving LAM treatment for 2 years from 2004 to 2007. HBV DNA level was assessed at baseline, 12, 24, 52, and 104 weeks after treatment. Risk factors of tyrosine-methionine-aspartate-aspartate (YMDD) mutation on treatment and relapse rate of HBV after LAM discontinuation were analyzed.

RESULTS

HBV DNA levels became undetectable in 32, 37, 63, and 53% of patients after 12, 24, 52, and 104 weeks of LAM treatment, respectively. Overall, three (16%) and five (33%) patients were detected with YMDD mutations at week 52 and 104, respectively. In the concept of roadmap, of the seven patients with inadequate virologic response (IAVR) at week 24, five had YMDD mutations. There was no significant association of YMDD mutations with age, gender, genotype, cirrhosis, HBeAg status, baseline HBV DNA, precore/core promoter mutations, and primary response, except IAVR at week 24 (P = 0.001). The relapse rate of HBV after LAM discontinuation was high (75%) during a median follow-up of 65 weeks.

CONCLUSIONS

The rate of LAM resistance in RTRs is similar to immunocompetent CHB patients in a 2-year therapy. By roadmap concept, RTRs with IAVR require a change in therapy to prevent viral resistance. Relapse after LAM withdrawal is frequent. Long-term antiviral therapy is crucial for immunosuppressed patients.

Hepatitis B virus infection and renal transplantation

Although the prevalence of chronic hepatitis B virus (HBV) infection has declined in renal transplant recipients (RTRs), it remains a relevant clinical problem with high morbidity and mortality in long-term follow up. A thorough evaluation, including liver biopsy as well as assessment of HBV replication in serum (i.e. hepatitis B e antigen and/or HBV DNA) is required before transplantation. Interferon should not be used in this setting because of low efficacy and precipitation on acute allograft rejection. The advent of effective antiviral therapies offers the opportunity to prevent the progression of liver disease after renal transplantation. However, as far as we are aware, no studies have compared prophylactic and preemptive strategies. To date, the majority of RTRs with HBV-related liver disease have had a high virological and biochemical response to lamivudine use. However, lamivudine resistance is frequent with a prolonged course of therapy. Considering long-term treatment, antiviral agents with a high genetic barrier to resistance and lack of nephrotoxicity are suggested. The optimal strategy in RTRs with HBV infection remains to be established in the near future.

Response to adefovir or entecavir in renal allograft recipients with hepatitic flare due to lamivudine-resistant hepatitis B

We studied the effects of adefovir or entecavir in six kidney transplant recipients (mean age 45.7 +/- 7.8 yr) who developed hepatitic flare due to lamivudine-resistant hepatitis B virus (HBV) infection, with 18 months of follow-up. All patients had elevated alanine aminotransferase (ALT) levels and HBV DNA >10(5) copies/mL (median 2.15 x 10(8) copies/mL) at baseline. Serum creatinine and creatinine clearance levels were 137.8 +/- 59.7 mumol/L and 62.6 +/- 18.7 mL/min, respectively. Four patients were treated with adefovir and two with entecavir. Median HBV DNA decreased to 1.99 x 10(5) copies/mL (p = 0.028) after six months, 1.5 x 10(4) copies/mL (p = 0.043) after 12 months, and 7.35 x 10(4) copies/mL (p = 0.068) after 18 months of treatment. There was a corresponding improvement in ALT (34.5 +/- 19.1 U/L after 18 months, p = 0.029 compared with baseline). The rate of HBV DNA suppression was variable, and three patients took over six months for the viral load to decrease to <10(5) copies/mL. After 18 months, HBV DNA was <10(5) copies/mL in four patients and <10(2) copies/mL in one patient. Treatment was well-tolerated and renal function remained stable. We conclude that both adefovir and entecavir are effective in the treatment of lamivudine-resistant HBV in renal allograft recipients, and the reduction of HBV DNA to <10(5) copies/mL could be slow.

A case of acute rejection shortly after initiation of lamivudine therapy in a simultaneous pancreas and kidney recipient with viral hepatitis type B

We describe a patient with hepatitis B antigenemia, who received a simultaneous pancreas and kidney transplant, developed reactivation of hepatitis B virus infection with aminotransferase elevation, and unexpectedly suffered an acute rejection episode within a few weeks after initiation of lamivudine therapy. At the time of rejection diagnosis, the cyclosporin A (CyA) trough level was 2 times lower than before the start of lamivudine therapy. Only an improvement in liver CyA metabolism in the course of lamivudine therapy can explain such an essential decline. Thus, it is important to emphasize how crucial it is to frequently monitor the CyA level in the early period of lamivudine therapy in transplanted patients with hepatitis to ensure adequate immunosuppression and to avoid acute rejection episodes.

Clinical course of hepatitis B virus infection in renal allograft recipients

The outcome of renal transplantation is adversely affected by hepatitis B virus infection. We retrospectively analyzed data of 1,251 renal transplant recipients, 20 of whom were hepatitis B surface antigen positive and hepatitis B virus DNA negative at the time of renal transplantation. Hepatitis B virus reactivation was seen in 14 of the 20 patients at a mean time of 16.3+/-7.1 months after transplantation. All patients with hepatitis B virus reactivation after transplantation were treated with lamivudine, biochemical, and serologic response was achieved in 13 of 14 patients at a mean time of 7.0+/-1.1 months. Seven of 13 patients experienced a breakthrough at a mean time of 9.2+/-6.2 months. Three of the 20 patients died at a mean time of 57.0+/-38.5 months after transplantation. Our data demonstrated that chronic immunosuppression is associated with a significantly high risk of hepatitis B virus reactivation in renal transplant recipients and hepatitis B reactivation does not increase the likelihood of graft rejection or patient mortality after renal transplantation.