C. pneumoniae: Chronic obstructive pulmonary disease (COPD).
COPD is a condition where there is airflow obstruction secondary to chronic bronchitis or emphysema. Unlike asthma, there is always some degree of obstruction, but acute infections can cause exacerbations. A limited number of studies have investigated the role of C. pneumoniae as a cause of COPD, but only recently has there been a prospective study [Strachan et al., 2000]. This showed that in men who already had COPD, disease progression was not associated with C. pneumoniae seropositivity. Cross sectional studies have also failed to provide convincing evidence for an association. Although 2 studies reported an association [Blasi et al., 1993; von Hertzen et al., 1997], others have shown no clear link [Beaty et al., 1991; von Hertzen et al., 1996]. In acute COPD exacerbations, an increase in C. pneumoniae antibody titre has been seen in between 7 to 18% of cases [Blasi et al., 1993; Beaty et al., 1991; von Hertzen et al., 1996; Mogulkoc et al., 1999; Soler et al., 1998; Torres et al., 1996].
[MEW update at March 2002: A study by Lieberman et al., 2001 in Israel of 250 in-patients with COPD found serological evidence of a higher correlation rate with C. pneumoniae but no evidence that the C. pneumoniae enhanced the severity of the disease. For a review, see Hahn et al., 2002].
NEXT: Coronary Artery Disease (CAD)
Beaty, C. D., Grayston, J. T., Wang, S. P., Kuo, C. C., Reto, C. S. & Martin, T. R. (1991). Chlamydia pneumoniae_, strain TWAR, infection in patients with chronic obstructive pulmonary disease. American Review of Respiratory Disease 144, 1408 - 1410.
Blasi, F., Legnani, D., Lombardo, V. M., Negretto, G. G., Magliano, E., Pozzoli, R. et al. (1993). Chlamydia pneumoniae_ infection in acute exacerbations of COPD. European Respiratory Jpurnal 6,19 - 22.
Hahn, D.L., Azenabor, A. A., Beatty, W. L. & Byrne, G. I. (2002). Chlamydia pneumoniae_ as a respiratory pathogen. Front Bioscience 7, E66 - 76.
von Hertzen, L., Isoaho, R., Leinonen, M., Koskinen, R., Laippala, P., Toyryla, M. et al. (1996). Chlamydia pneumoniae_ antibodies in chronic obstructive pulmonary disease. International Journal of Epidemiology 25, 658 - 664.
von Hertzen, L., Alakarppa, H., Koskinen, R., Liippo, K., Surcel, H. M., Leinonen, M. et al. (1997). Chlamydia pneumoniae infection in patients with chronic obstructive pulmonary disease. Epidemiol Infect 118, 155 - 164.
Lieberman, D., Ben-Yaakov, M., Lazarovich, Z., Ohana, B. & Boldur, I. (2001). Chlamydia pneumoniae infection in acute exacerbations of chronic obstructive pulmonary disease: analysis of 250 hospitalizations. European Journal of Clinical Microbiology and Infectious Disease 20, 698 - 704.
Mogulkoc, N., Karakurt, S., Isalska, B., Bayindir, U., Celikel, T., Korten, V. et al. (1999). Acute purulent exacerbation of chronic obstructive pulmonary disease and Chlamydia pneumoniae infection. American Journal of Respiratory and Critical Care Medicine 160:349-53. Full article
Soler, N., Torres, A., Ewig, S., Gonzalez, J,. Celis, R., El Ebiary, M. et al. (1998). Bronchial microbial patterns in severe exacerbations of chronic obstructive pulmonary disease (COPD) requiring mechanical ventilation. American Journal of Respiratory and Critical Care Medicine 157, 1498 - 1505. Full article
Strachan, D. P., Carrington, D., Mendall, M., Butland, B. K., Yarnell, J. W. & Elwood, P. (2000). Chlamydia pneumoniae_ serology, lung function decline, and treatment for respiratory disease. American Journal of Respiratory and Critical Care Medicine 161, 493 - 497. Full article
Torres, A., Dorca, J., Zalacain, R., Bello, S., El Ebiary, M., Molinos L., et al. (1996). Community-acquired pneumonia in chronic obstructive pulmonary disease: a Spanish multicenter study. American Journal of Respiratory and Critical Care Medicine 154, 1456 - 1461.