1552. Absolute Lymphocyte Threshold: A Simple Readily Available Tool to Predict Risk of Cytomegalovirus Infection After Transplantation

Abstract

BackgroundCytomegalovirus (CMV) is a common infection after solid-organ (SOT) and hematologic stem cell transplantation (HSCT). We correlated peripheral blood absolute lymphocyte count (PBALC) with risk of CMV infection in transplant patients.MethodsThirty-six SOT and 28 HSCT consecutive patients with plasma CMV viral load (VL) testing for surveillance were enrolled. Clinical variables, including PBALC, were abstracted for correlation with CMV infection.ResultsThe median age was 54.5 years (IQR 40–63). Forty-three (67.2%) patients developed CMV infection (asymptomatic, 67.4%; CMV syndrome, 14%; gastrointestinal disease, 14%) at median of 4.4 months (IQR 1.4–7.7). Median VL was higher for symptomatic than asymptomatic infection (10,110 vs. 262 IU/mL, P = 0.006). PBALC <830 cells/mm3 correlated with CMV infection (sensitivity 95%; specificity 71%). Median PBALC among CMV infection patients was lower than those without infection (450 vs. 1,060 cells/mm3, P < 0.0001). Among SOT patients, PBALC <610 cells/mm3 correlated with CMV infection (sensitivity 80%; specificity 73%); median PBALC was significantly lower among those who developed CMV infection (270 and 450 vs. 1,120 cells/ mm3). Among HSCT recipients, PBALC <830 cells/mm3 correlated with CMV infection (sensitivity 100%; specificity 80%); median PBALC was lower among those who developed CMV infection (520 and 510 vs. 1,020 cells/ mm3) (Table 1).ConclusionIn the current era when sophisticated immunologic measures are being proposed as CMV prognosticator, we highlight the clinical importance of a simple readily available PBALC.Table 1.CMV VL and PBALC in Patients with or Without CMV InfectionCMV DiseaseAsymptomatic CMV ViremiaNo CMV infectionI P ValueSOT, N = 36 N = 7 N = 18 N = 11Median CMV VL (IQR) (IU/mL)32,500 (352–118,000)423 (297–6,315)00.05*Median PBALC(IQR) (cells/mm3)270 (140–460)450 (388–675)1,120 (590–1,400)0.001HSCT, N = 28 N = 3 N = 15 N = 10Median CMV VL (IQR) (IU/mL)1,220 (426–2,520)884 (347–1,980)00.62*Median PBALC (IQR) (cells/mm3)520 (300–560)510 (330–670)1,020 (795–3,308)0.03PBALC, peripheral blood absolute lymphocyte count; CMV, cytomegalovirus; HSCT, hematologic stem cell transplantation; IQR, interquartile range; SOT, solid-organ transplantation; VL, viral load.*Comparison between CMV disease and CMV viremia recipients. Disclosures All authors: No reported disclosures.