For pediatric kidney recipients, subclinical inflammation is associated with increased risk for acute rejection and allograft failure, according to a study published online May 15 in the American Journal of Transplantation

Michael E. Seifert, M.D., from the University of Alabama School of Medicine in Birmingham, and colleagues conducted a retrospective cohort study involving 120 consecutive pediatric kidney recipients, of whom 103 had surveillance biopsies within six months after transplant.

Researchers conducted a single?center retrospective cohort study of 120 consecutive pediatric kidney recipients, of whom 103 had surveillance biopsies ≤ 6 months post?transplant.

They tested the hypothesis that subclinical inflammation (borderline or T cell?mediated rejection without clinical dysfunction) is associated with a 5?year composite endpoint of acute rejection and allograft failure.

Results

Overall, 36% of subjects had subclinical inflammation, which was associated with an increased hazard for the composite endpoint [adjusted hazard ratio 2.89 (1.27, 6.57); P<0.01].

Subjects with treated versus untreated subclinical borderline rejection had a lower incidence of the composite endpoint (41% versus 67%; P<0.001). Subclinical vascular injury (subclinical inflammation with Banff arteritis score > 0) had a 78% incidence of the composite endpoint versus 11% in subjects with no major surveillance abnormalities (P<0.001).

The researchers found that 36% of subjects had subclinical inflammation, which was correlated with increased risk for the composite endpoint of acute rejection and allograft failure (adjusted hazard ratio, 2.89).

The incidence of the composite endpoint was significantly lower for subjects with treated versus untreated subclinical borderline rejection (41 versus 67 percent). The incidence of the composite endpoint was 78% for those with the subclinical vascular injury versus 11 percent in subjects with no major surveillance abnormalities.

"We showed that subclinical inflammation phenotypes were prevalent in pediatric kidney recipients without clinical dysfunction and were associated with increased acute rejection and allograft failure," the authors write. "Once prospectively validated, our data would support the implementation of surveillance biopsies as a standard of care in pediatric kidney transplantation."