Spectrum and antimicrobial resistance of common pathogenic bacteria isolated from patients with acute exacerbation of chronic obstructive pulmonary disease in mainland of China.

BACKGROUND: Bacteria-induced respiratory infection has been long considered to be the major cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Therefore, a clear picture about the distribution and drug-resistance of pathogenic bacteria in the lower airways should be helpful for treatment of the disease. So far, data on this topic among Chinese are lacking. METHODS: A surveillance study was performed in consecutive patients with AECOPD at five areas in China between October 2006 and April 2008. The sputum from these patients was cultured and isolated for bacteria. Agar dilution method was used to determine the minimal inhibitory concentrations (MICs) of levofoxacin and other 15 antibiotics against these strains. RESULTS: Three hundred and fifty-nine pathogenic bacterial strains were isolated among 884 patients with AECOPD. The predominant bacteria were Pseudomonas aeruginosa (21.7%), Klebsiella pneumoniae (12.3%), Haemophilus influenzae (14.2%) and Streptococcus pneumoniae (11.7%), followed by Haemophilus parainfluenzae (9.5%), Acinetobacter baumannii (7.8%), Moraxella catarrhalis (6.4%) and Escherichia coli (3.6%). The majority of bacterial pathogens isolated in this study were susceptible to fuoroquinolones, ceftazidime, cefepime and imipenem. CONCLUSIONS: Gram-negative bacilli are the leading pathogens in patients with AECOPD in China. Haemophilus parainfluenzae may be one of the most important pathogens in AECOPD. This study provides evidence for local surveillance of AECOPD pathogens and appropriate choice of antimicrobials in China.

An Asian study on the prevalence of atypical respiratory pathogens in community-acquired pneumonia.

BACKGROUND: In many parts of Asia, the inaccessibility and high cost of diagnostic tests have hampered the study of community-acquired pneumonia (CAP) caused by atypical respiratory pathogens. OBJECTIVE: This surveillance study examined the frequency of infection with Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Legionella pneumophila in 1756 patients presenting with signs and symptoms of CAP at 12 medical centres in Asia, using standardised laboratory techniques and interpretation criteria in all participating centres. METHODS: Diagnosis of current infection was based on significant changes in antibody titer or persisting high antibody titers, together with the presence of bacterial DNA in respiratory secretions, in the case of M. pneumoniae and C. pneumoniae infections, or bacterial antigen in urine, in the case of L. pneumophila serogroup 1 infection. RESULTS: Using these criteria, results from 1374 patients with paired sera showed that, overall, 23.5% of CAP cases were associated with infection with atypical respiratory pathogens, with M. pneumoniae, C. pneumoniae, and L. pneumophila being found in 12.2%, 4.7%, and 6.6% of cases, respectively. Persisting high antibody titers indicative of past exposure to M. pneumoniae, C. pneumoniae, and L. pneumophila were seen in 10.2%, 4.8%, and 18.9% of patients, respectively. CONCLUSION: These data reflect the overall high prevalence of these atypical pathogens among Asian patients with CAP.