Sunday, February 9, 2014

Hepatitis B and kidney transplantation

Prior HBV infection is not a contraindication to kidney transplantation. 

It is critical to evaluate patients with serologies and HBV DNA viral load prior to transplant. Most patients should also undergo liver transplant biopsy to exclude significant fibrosis/cirrhosis.
Patients with low risk of reactivation are antiHBc positive and HBsAb positive. Those at higher risk of reactivation have + HBV VL and/or + HBeAg. Those patients with cirrhosis or portal hypertension would benefit of a combined liver/kidney transplant.

The risk of reactivation of HBV under long-term immunosuppression in hepatitis B core antibody-positive, hepatitis B surface antigen (HBsAg)-negative transplant recipients was evaluated over a 3-yr period in 49 transplant recipients (27 liver, 18 kidney, 4 pancreas); 37 recipients (76%) were HBsAb-positive at transplantation (Duhart, Honaker et al. Transp Infect Dis 2003). There was no incidence of HBV reactivation defined as recurrence of HBsAg and/or HBV DNA positivity, suggesting that the risk of reactivation of HBV in hepatitis B core antibody-positive, HBsAg-negative transplant recipients was low with immunosuppression. In the absence of HBsAg positivity, the reactivation of HBV should be assessed using HBV viral loads. 

Do patients with HBV infection benefit from kidney transplantation? 
Recent reports suggest that renal and patient outcomes are comparable to non-HBV infected patients, however, HBV+ patients do carry a 5x fold higher risk of liver failure. Reddy et al. reported no difference in the five-year patient or graft survival between 1346 HBsAg-positive and 74,335 HBsAg-negative recipients who were transplanted between 2001 and 2007 (85.3 versus 85.6 percent, respectively, for patient survival and 74.9 versus 75.1 percent, for graft survival) (Reddy, Sampaio, et al. CJASN 2011).

When should HBV+ patients be transplanted? 
In patients with no evidence of active HBV infection (negative HBV DNA viral load) or cirrhosis/portal hypertension, they may proceed with kidney transplantation. 

How should we manage HBV+ after kidney transplantation?
Prophylaxis with anti-viral therapy is recommended for at least 2 years in order to prevent reactivation. The ideal anti-viral agent is not known though entecavir is commonly used (lower HBV resistance) followed by lamivudine. 
All patients should be placed on a low intensity immunosuppressive regimen, avoiding T cell depleting agents. 
HBV DNA levels should be checked every three to six months to ensure viral suppression and for early detection of virologic breakthrough.

*Patients who are HBsAg neg, anti-HBs neg, but anti-HBc + may develop HBV reactivation after kidney transplantation, but the risk is relatively low. It is controversial whether these patients would benefit from routine antiviral prophylaxis.

Addendum: image from medasend.com

1 comment:

Mediart Life Sciences said...

thank you very much for this informative post on kidney transplantation.Please keep sharing some more new posts.
Transplantation