Impaired bactericidal and fungicidal activities of neutrophils in patients with myelodysplastic syndrome

Infections are a major cause of morbidity and mortality in patients with myelodysplastic syndrome (MDS) due to quantitative and qualitative granulocytic defects. We evaluated the in vitro bactericidal and fungicidal activities of neutrophils isolated from MDS. With comparison to those from healthy individuals, MDS neutrophils following infection showed a significantly reduced killing activity against Escherichia coli at 8 (p=0.002), 24 (p<0.0001), 48 (p=0.0005), and 72 h (p=0.0264), against Lactococcus lactis at 24 (p=0.0002), 48 (p<0.0001), and 72 h (p<0.0001), and more against Candida albicans at 8 (p=0.0003), 24 (p<0.0001), 48 (p<0.0001), and 72 h (p<0.0001). Our data show that MDS neutrophils have an impaired microbicidal function, which might account for the high susceptibility to infections of MDS patients.