Late acute rejection: incidence, risk factors, and effect on graft survival and function.

Long-term graft survival and function has not kept pace with short-term success in kidney transplant (Tx) recipients. LAR ≥6 months post-Tx may contribute to lack of improvement; risk factors for LAR are not well known. Of 64 Tx recipients followed over six yr, 23 (35.9%) had LAR (LAR group) and 41 had no LAR (no LAR group). Of all variables, significant risk factors for LAR included DGF, (43.4% LAR vs. 14.6% in no LAR group, p = 0.0096); de novo DSA (65.2% vs. 26.8%, p = 0.003); mean COV% of TAC (41.8% vs. 34.6%, p = 0.03); and non-adherence (34.8% vs. 7.3%, p = 0.0043). DGF and DSA remained statistically significant (p = 0.002 and 0.003, respectively); COV% TAC had borderline significance (p = 0.057), and non-adherence was not significant on multivariate regression analysis. Patients with LAR had inferior graft survival and function, whereas graft function was stable in the no LAR group over a mean follow-up of 31.2 months. Patients with de novo DSA and DGF should be considered at risk of LAR; an early diagnosis and treatment of LAR may improve graft survival and function.