During exacerbation, the inﬂammation in COPD is ampliﬁed in comparison with stable periods. The increased level of inﬂammatory markers is associated with lung function decline. As infection, is the main cause leading to clinical AECOPD, white blood cell counts and ESR are the common markers to show the existence of infection in patients with COPD. Recently, other bio markers are used. Authors have found that the high-affinity Fc receptor-CD64 is expressed by monocytes and only weakly on resting neutrophils. The high-expression of neutrophil CD64 (nCD64) is an early step in the host- immune response to bacterial infection. Studies have shown that the nCD64 might be used as a bio-marker for early-onset sepsis or bacterial infection. However, authors agreed that the value of the nCD64 in COPD prognosis is unknown.