2508. Absolute Lymphocyte Count and Adenovirus-Specific CD8+ T-cell Immunity as Immunological Predictors of Severe Adenovirus Disease After Kidney Transplantation

Abstract

BackgroundAdenovirus (ADV) infection after kidney transplantation (KT) can range from asymptomatic to severe disease. Cell-mediated immunity plays an important role in preventing disease progression. We aimed to investigate the role of absolute lymphocyte count (ALC) and ADV-specific CD8+ T cell immunity to predict the severity of ADV infection in KT recipientsMethodsWe included all adult KT recipients with ADV infection at a single transplant center between January 2015 and March 2018. ADV infection/disease were defined as detectable ADV DNA load in plasma/plus symptoms. We defined severe ADV disease as having plasma ADV DNA load >6.0 log copies/mL and/or disseminated disease (≥2 specific organ symptoms). ADV specific CD8+ T cells were stimulated with whole ADV peptide, stained by intracellular cytokine staining and interrogated by flow cytometry. ALC (all patients) and ADV-specific CD8+ T-cell (7 index cases) were measured at diagnosis. The association of ALC and disease progression were assessed in those with and without severe disease.ResultsADV infection was diagnosed in 14 KT recipients, 12 (86%) patients were male with a median age of 44 (IQR, 37–58) years. Ten (71%) recipients underwent deceased donor KT and none received anti-thymocyte globulin for induction therapy. ADV infection occurred at median of 14 (IQR, 2–37) months after KT. Eight (57%) recipients were defined as having severe ADV disease including disseminated ADV disease (n = 5). Median peak plasma ADV load was higher in those with severe disease compared with those without severe disease [6.0 (IQR 5.9–6.0) vs. 5.3 (IQR 3.9–5.4) log copies/mL (P = 0.003)]. Median ALC and ADV-specific CD8+ T cells at diagnosis were 1,000 (IQR 623–1,350) and 0.003 cells/mm3, respectively. KT recipients with severe disease had lower median ALC at diagnosis compared with those without severe disease [714 (IQR 419–860) vs. 1,264 (IQR 972–2,086) cells/mm3; P = 0.04) (Figure 1). Those with ALC <1,000 cells/mm3 at diagnosis had greater risk of severe disease [OR 35 (95% CI, 2.6–1,450); P = 0.006].ConclusionLack of ALC and ADV-specific CD8+ T cell immunity (limited data) at diagnosis could potentially be immunological predictors of severe ADV infection in KT recipients. Disclosures All authors: No reported disclosures.