The relationship between the antibody titre of Chlamydophila pneumoniae and clinical presentation, in patients with respiratory tract symptoms

Abstract number: 1734_153

Ueda K., Nakamura T., Morikawa T., Moriyama A.

Objectives: Persistent infection by several microorganisms such as Helicobacter pylori has been shown to be associated with diseases other than infectious diseases. There have been reports that persistent infection by Chlamydophila pneumoniae is a risk factor for cardiovascular diseases but the relation is not clear. We reported at the 2005 Annual Meeting of The Japanese Society of Internal Medicine that when anti-C. pneumoniae IgA and IgG in patients with respiratory tract symptoms were measured, the ratio of patients considered to have acute C. pneumoniae infection constituted about 10% (12.8%) and patients that were IgG antibody positive constituted about 70% (70.4%). In this study we noticed that there were cases in which IgA or IgG was maintained at strong-positive for half a year or longer. After careful examination, we had an impression that these were serious. Here we studied the difference in clinical presentation between antibody negative and strong-positive to investigate whether infection by C. pneumoniae infection is associated with other diseases.

Methods: We investigated IgG in 244 specimens and the clinical presentation of the patients (total 207; 93 males; 114 females; age 16–99; average age 70.4) whose IgG was measured due to their presentation of respiratory tract symptoms at our hospital from 1 August 2004 to 31 August 2006. A specific antibody measuring kit which uses the ELISA method in which the outer membrane complex of C. pneumoniae is the antigen (HITAZYME C. Pneumoniae: Hitachi Chemical Co., Ltd.) was used. An index 3 or above was defined as strong-positive and less than 0.9 was defined as negative.

Results: 59 cases (28.5%) were negative and 13 cases (6.3%) were strong-positive. The average age of the negative was 61, and 82 in the positive, indicating that the negative were younger (P < 0.01). The ratio of deaths by 31 October 2006 was 15.3% in negative and 61.5% in strong-positive, indicating a higher ratio in the strong-positive (P < 0.01). The cases of cerebrovascular disorder were found in 25.4% of negative and 38.5% in strong-positive (P = 0.42).

Conclusion: The strong-positive patients for C. pneumoniae antibody were significantly older in age compared to the negative, and significantly more of the strong-positve patients died within 2 years of the measurement as compared to the negative. Although statistically not significant, there were more cases of cerebrovascular disorder in the strong-positive cases.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
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