Ra SW, et al. – This study was carried out to investigate the association between detection of potentially pathogenic bacteria (PPB) using sputum culture or polymerase chain reaction (PCR) and clinical response and sought the risk factors for PPB growth. According to the findings obtained, neither culture growth nor PCR positivity for H. influenzae (HI) or S. pneumoniae (SP) in sputum predicted clinical response to antibiotics. Therefore, these tests are not necessary for outpatients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Further analyses revealed that examining Gram–staining and purulence on sputum smear, however, was significant to predict PPB growth in sputum.

Methods

• In three hundred forty-two outpatients with AECOPD, detection rates of H. influenzae (HI) and S. pneumoniae (SP) were compared utilizing conventional sputum culture versus PCR.
• The utility of either technique to predict clinical cure or failure after effective antibiotics was surveyed.
• The factors anticipating positive sputum cultures were assessed utilizing logistic regression.

Results

• 132 PPB were detected using sputum culture.
• It was observed in the findings that the predominant bacteria were HI (40.9%) and SP (19.7%).
• Findings revealed that detection of HI or SP in sputum was higher using PCR than culture growth (60.8% vs 18.6%; p<0.001).
• Clinical response was not influenced by the results of either technique.
• Data reported that independent risk factors for PPB isolation were Gram-negative bacteria on sputum smear (OR 15.78, 95% CI 6.38-39.06; p<0.001), sputum purulence (OR 2.31, 95% CI, 1.05-5.11; p=0.04), body temperature (OR 0.16, 95% CI 0.05-0.54; p=0.003), albumin level (OR 0.29, 95% CI 0.09-0.88; p=0.03), and dyspnea grade (OR 0.51, 95% CI 0.27-0.96; p=0.04).