Value of lipopolysaccharide binding protein as diagnostic marker of infection in adult cancer patients with febrile neutropenia: comparison with C-reactive protein, procalcitonin, and interleukin 6

Early detection of infection is essential for initial management of cancer patients with chemotherapy-associated febrile neutropenia in the emergency department. In this study, we evaluated lipopolysaccharide binding protein (LBP) as predictor for infection in febrile neutropenia and compared with other biomarkers previously studied: C-reactive protein (CRP), procalcitonin (PCT), and interleukin (IL)-6. A total of 61 episodes of chemotherapy-associated febrile neutropenia in 58 adult cancer patients were included. Serum samples were collected on admission at emergency department and CRP, LBP, PCT, and IL-6 were measured. Patients were classified into fever of unknown origin and infection, including microbiologically and clinically documented infection, groups. Receiver operating characteristic (ROC) curve analysis was performed for each biomarker for the diagnosis of infection. Thirty-two of the 61 episodes were classified as infection. On admission, CRP, PCT, IL-6, and LBP were significantly increased in patients with infection compared to fever of unknown origin group. Area under the ROC curve (AUC ROC) of CRP, PCT, IL-6, and LBP for discriminating both groups was 0.77, 0.88, 0.82, and 0.82, respectively, without significant difference between them. The combination of IL-6 and PCT or LBP did not lead to a significant improvement of the diagnostic accuracy of PCT or LBP alone. On admission, LBP has a similar diagnostic accuracy than PCT or IL-6 for the diagnosis of infection and might be used as additional diagnostic tool in adult cancer patients with chemotherapy-associated febrile neutropenia.