Background Chronic obstructive pulmonary disease (COPD) is a chronic debilitating disease. Acute exacerbation of COPD (AECOPD) determines the extent of disease morbidity, healthcare utilization, associated costs, and mortality. Patients with COPD who have chronic colonization would not only have greater burden of inflammation and more frequent exacerbations but also a faster decline in pulmonary functions. Hence, our study was conducted. Patients and methods A total of 125 patients were enrolled in this cross-section study, which was conducted at Chest Department and Respiratory ICU. Laboratory analysis of the study samples was performed in Medical Microbiology and Clinical Pathology Departments, Faculty of Human Medicine, Zagazig University Hospitals, in the period between May 2018 and July 2019. Objective The aim was to examine the value of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) as a promising inflammatory biomarker in detecting chronic bacterial colonization and to settle the cutoff value for the suggested infection index in identifying bacterial colonization. Results Based on sputum culture results, patients were classified into two groups: group A (those with bacterial colonizers) and group B (those with no bacterial colonizers). All assessed laboratory tests were significantly higher in patients with exacerbated COPD with bacterial colonization. Conclusion sTREM-1 is a valid and reliable inflammatory biomarker and can determine the presence of chronic bacterial colonizers. Infection index (procalcitonin+sTREM-1) should be applied and measured for admitted AECOPD with exacerbations of noninfective type, and this would guide antibiotic usage and limit overutilization of antibiotics in noninfective patients with AECOPD.