PATHOLOGY: IMMUNE AND INFLAMMATORY MECHANISMS

2 and 3 were observed in 43%, 47% and 10% of these specimens. Leucocyte subpopulations were categorized focal vs. diffuse monocytic (11%/24%), focal vs. diffuse granulocytic (4%/4%), or focal vs. diffuse mixed (14%/20%). In 23% of the cases ptc was not classified (e.g. vicinity of tubular necrosis, pyelonephritis or infarct). Ptc scores (1, 2 or 3) were associated with both diagnosis of AMR and cellular rejection (ACR). Diffuse monocytic or mixed ptc (OR=4.51, 95% CI 1.82-11.16, and OR=6.8, 2.44-19.36, p≤0.001), but not granulocytic ptc (OR=3.81, 95% CI 0.41-35.02, p=0.2) were associated with AMR. At the same time, diffuse ptc was associated with ACR, regardless of its composition (monocytic: OR=6.1, 95%CI 3.61-12.44; granulocytic: OR=6.69, 1.58-28.41; mixed: OR=8.05, 4.06-15.96; p≤0.01). In uni- and multivariate analysis ptc 3 (OR=2.56, 95%CI 1.24-1.96, p=0.011), diffuse monocytic or mixed ptc (OR=1.75, 95%CI 1.01-3.06, p=0.048 and OR=1.75, 1.03-3.26, p=0.04) were risk factors for inferior graft survival. Conclusions: Our results underscore a high relevance of the detailed qualitative and quantitative characterization of peritubular capillaritis in indication biopsies as a predictor for inferior clinical outcomes.