Liver and kidney
transplant can be justified for carefully selected HIV-positive patients,
researchers from the United States show in AIDS.
Transplant improved the chances of survival for HIV-positive patients with
severe liver disease. Comparison with HIV-negative transplant patients showed
that HIV-positive liver patients were more likely to experience organ rejection
or die, but the difference in risk for both these outcomes was small.
“The modest
increase in risk compared with HIV-negative recipients, as well as the absolute
proportion of those who died, and comparability with other transplant
populations, support liver transplant as a viable option in carefully selected
and managed recipients,” comment the authors. “HIV-positive kidney recipients
experienced similar outcomes as their HIV-negative counterparts approximately 5
years post-transplant in all control analyses.”
Approximately 2%
of patients with HIV develop kidney failure and end-stage liver disease is an
increasingly important cause of death in the HIV-infected population. This
means that a growing proportion of HIV-positive patients require kidney or
liver transplants. However, it has been questioned if patients with HIV are
good transplant candidates.
Investigators from
San Francisco therefore designed a study to determine if the prognosis of
patients was improved by transplantation and to compare outcomes between
HIV-positive and HIV-negative transplant recipients in terms of graft loss and
death. The study also examined if any factors were associated with organ
rejection of death in patients with HIV, rates of infections and
hospitalisation, and the impact of transplant on key HIV markers, including CD4
count and viral load.
The HIV-positive
study population consisted of 125 liver and 150 kidney transplant patients who
underwent transplantation between 2003 and 2010. Their outcomes were compared
with HIV-positive patients who were candidates for liver (n = 148) or kidney (n
= 167) transplant who received care in the same period but who did not receive a new
organ. The kidney patients had a CD4 cell count above 100 cells/mm3
and an undetectable HIV viral load; liver patients had CD4 counts above 200
cells/mm3 and either an undetectable viral load or the possibility
of establishing viral control after transplant.
Liver and kidney
recipients were followed for a median of 3.5 and 4.0 years, respectively.
Candidates were monitored for approximately a year.
Transplant was
associated with a significant survival benefit (p < 0.0001) for patients
with more severe liver disease (MELD score of at least 15), but not for
patients with less severe liver disease or for kidney recipients.
Factors associated
with increased mortality risk for liver transplant patients included dual
transplant (hazard ratio 3.8, 95% confidence interval 1.6-8.8,p = 0.002), low pre-transplant body mass index, or BMI (HR 2.2, 95% CI 1.1-4.4, p = 0.03),
older donor age (HR 1.3 per decade, 95% CI 1.1-1.6, p = 0.01) and co-infection with hepatitis C virus, (HR 2.1, 95% CI 1.0-4.6, p = 0.06).
The same factors were associated with graft loss.
Risk factors for
increased mortality risk among kidney recipients included older age at the time
of transplant (HR 1.07 per decade, 95% CI 1.1-1.26, p = 0.01) and therapy with thymoglobulin in in the first week after
transplant (HR 3.5, 95% CI 1.3-9.1, p = 0.01). Treatment with this drug was also associated with organ
rejection (p = 0.048).
Twelve
AIDS-defining opportunistic infection (cutaneous Kaposi’s sarcoma, esophageal
or bronchial candidiasis, PCP pneumonia) were observed in liver transplant
patients and four of these individuals died, the causes of death being
multi-system organ failure, cerebrovascular accident and recurrent HCV
infection.
Three kidney recipients
experienced a recurrence of HIV-associated kidney disease. Their CD4 count at
the time of recurrence ranged between 0 and 770 cells/mm3.
Serious
non-HIV-related infections were observed in 55% of liver and 50% of kidney
recipients. Half occurred in the first six months post transplant. For both
liver and kidney recipients, most of these infections were bacterial (80% and
71%, respectively). HCV co-infection was associated with an increased risk of
infections for both groups of transplant patients.
For liver
patients, there was some evidence of post-transplant recovery in CD4 cell
count.
Over three years
of follow-up, 20% of liver patients and 16% of kidney patients experienced an
increase in their HIV viral load to detectable levels. Most, however,
subsequently re-established viral control.
The risk of
graft-loss and death was compared between the patients with HIV and
HIV-negative patients. The investigators conducted four sets of comparison:
unmatched, demographically-matched, demographically-matched adjusted for risk
score and risk-matched. HIV-negative patients were identified in national
databases. Median follow-up was approximately four years.
For kidney
recipients, unmatched and risk-matched analysis showed that HIV-positive
patients had marginally significant increases in the risk of organ rejection (p
= 0.07 and p = 0.52, respectively). All models showed that HIV-positive liver
recipients had an increase in the risk of graft loss compared to the controls.
HIV was not
associated with an increased risk of death after kidney transplant.
HIV-positive liver recipients had an increased risk of death in the unmatched
(p = 0.01), demographically-matched (p = 0.01) and demographically-matched
risk-score adjusted (p = 0.01) models, but not the risk-matched model. “The
absolute difference in the proportion of deaths was 6.7% in the risk-matched
control analysis,” note the investigators.
“These analyses
support kidney and liver transplantation as an option for carefully selected
people with HIV infection,” conclude the authors.