Chlamydia pneumoniae infection and acute exacerbation of chronic obstructive pulmonary disease (COPD)

Abstract

The objective of the study was to investigate the possible association of Chlamydia pneumoniae (Cpn) in acute exacerbations of chronic obstructive pulmonary disease (COPD) patients. Thirty-eight acutely exacerbated COPD patients and 17 healthy smokers were enrolled in the study, as the study and control groups respectively. Nasopharyngeal swabs and paired serum samples for antibody testing of Cpn (microimmunofluorescence--MIF) were obtained from all subjects. Sputum cultures of COPD patients were also performed. No pathogenic bacteria were isolated from nasopharyngeal swabs in any subject. Serologic evidence of recent Cpn infection was observed in 13 (34%) COPD patients and in one (5%) control subject. The prevalence of Cpn IgG and IgM antibodies representing acute infection were significantly higher in COPD patients than in control subjects (P < 0.05 and P < 0.01 respectively). Prevalence of IgA antibodies and IgG pre-existing antibodies did not show any difference (P > 0.05). Microbiologic culture of the sputa yielded potentially pathogenic micro-organisms in 23 of 38 (60%) COPD patients. Alpha-haemolytic streptococcus (35%), Niesseria spp. (31%) and Candida spp. (9.5%) were most prominent micro-organisms in positive cultures. Although a high prevalence of IgG antibodies against Cpn was detected, it was the sole causative agent in only four (10%) patients. We conclude that a remarkable number of COPD patients (34%) are acutely infected with Cpn and it may either be the sole causative agent or frequently a co-agent in acute exacerbations.

Atypical pathogens and respiratory tract infections

“…H. influenzae, M. catarrhalis, S. pneumoniae and C. pneumoniae are the most important causes of acute exacerbation of bacterial origin [78]; although, the incidence of C. pneumoniae in patients with acute exacerbations of chronic bronchitis (AECB) appears to vary considerably from as low as 4-5% to w30% (table 2) [72,75,[79][80][81][82][83][84].…”

Evolution to a Chronic Disease Niche Correlates with Increased Sensitivity to Tryptophan Availability for the Obligate Intracellular Bacterium Chlamydia pneumoniae

“…While there is a body of published evidence linking C. pneumoniae and cardiovascular disease, a causal link remains to be definitively proven and is considered controversial by some. In addition to the link with cardiovascular diseases, it has also been linked with asthma (49), Alzheimer's disease (50,51), arthritis (52), lung cancer (53-55), chronic obstructive pulmonary disease (56,57), and diabetes (58,59). While there continue to be individual reports of severe respiratory disease associated with C. pneumoniae (60), it appears that the norm is now an association of C. pneumoniae with a range of chronic diseases.…”

Chlamydia: Possible Mechanisms of the Long Term Complications

“…Smoking was associated with increased level of C. pneumoniae serum antibody levels. It is presumed that smoking may facilitate C. pneumoniae infection in lung with chronic epithelial damage or promote deeper penetration into lung tissue to produce a greater antibody response (Karnak et al, 2001). High IgG and IgA antibody titers against C. pneumonia are linked with the severity of emphysema high resolution CT and increased IgA titers is also associated with decreased diffusion capacity to carbon monoxide (Kurashima et al, 2005).…”