Expression of CD11b/CD18 adhesion molecules on circulating phagocytes—a novel aid to diagnose infection in patients with cancer

Abstract

No blood marker available to date is useful for distinguishing infection-related from neoplasm-related fever. We evaluated the expression of the peripheral blood phagocyte CD11b/CD18 adhesion molecule complex for this purpose. Neutrophil and monocyte CD11b/CD18 expression was assessed in two cohorts of patients with advanced solid cancer (n = 120) and in healthy controls (n = 63). The cancer series included 89 patients with verified infection, 23 without infection, and eight with neoplastic fever. CD11b/CD18 expression was measured using flow cytometry, and serum C-reactive protein (CRP) concentration was determined with immunoturbidimetric assay. Cancer patients with infection had higher blood neutrophil and monocyte CD11b/CD18 expression levels than patients with neoplastic fever, those with advanced cancer without infection, or healthy controls (p < 0.01 for all analyses). High CD11b/CD18 values were measured exclusively in individuals diagnosed with infection. Receiver-operating characteristic area under the curve (AUC) for neutrophil and monocyte CD11b/CD18 expression for the discrimination of infection from neoplastic fever was 0.80 (95% CI, 0.70 to 0.88), which was superior (p = 0.039 and p = 0.049, respectively) to serum CRP on admission (AUC 0.51, 0.40 to 0.62). Peripheral blood phagocytic cell CD11b/CD18 expression is useful for making a differential diagnosis between infection and neoplasm-related fever in cancer patients.