Lipopolysaccharide-binding protein: a possible diagnostic marker for Gram-negative bacteremia in neutropenic cancer patients

Abstract

Objective: Cancer patients with febrile neutropenia after chemotherapy have a variable risk of bacterial infection. Especially Gram-negative bacteremia is associated with high mortality and/or morbidity. Early diagnosis of patients with Gram-negative bacteremia at the onset of febrile neutropenia is potentially useful in tailoring therapy.

Design and setting: Prospective study at the Department of Pediatric Oncology and Internal Medicine of a university hospital.

Patients: Were analyzed 66 febrile neutropenic episodes in 57 adults and children. Patients were divided into four groups: those with Gram-negative bacteremia, Gram-positive bacteremia, clinical sepsis, or fever of unknown origin.

Measurements and results: Plasma lipopolysaccharide-binding protein (LBP) and C-reactive protein (CRP) concentrations were determined. LBP at the onset of febrile neutropenia was significantly higher in patients with Gram-negative bacteremia than those with fever of unknown origin and those with Gram-positive bacteremia. Using a cutoff value for LBP proved to have much greater sensitivity, specificity, and positive and negative predictive value for Gram-negative bacteremia than the best cutoff value for CRP.

Conclusions: An initial high LBP level might predict Gram-negative bacteremia in cancer patients with febrile neutropenia. These results may have potential clinical impact by allowing therapy to be initiated for these patients at a very early stage.