Presence of Chlamydia pneumoniae in abdominal aortic aneurysms is not associated with increased activity of matrix metalloproteinases

Eur J Vasc Endovasc Surg. 2002 Oct;24(4):365-9. doi: 10.1053/ejvs.2002.1726.


Objective: to test the hypothesis that the presence of Chlamydia pneumoniae (C. pneumoniae) in the wall of abdominal aortic aneurysms (AAA) is associated with increased activity of matrix metalloproteinase (MMP)-2 and/or MMP-9.

Design: case-control study.

Material and methods: in a series of 40 patients with AAA > or =5cm in maximal cross-sectional diameter, C. pneumoniae-DNA was identified in the aneurysm wall by nested PCR in 14 (35%) patients. Another 14 C. pneumoniae-DNA-negative AAA patients from the same series, matched for gender and aneurysm diameter, were used as controls. In each group there were 7 asymptomatic (aAAA) and 7 ruptured (rAAA) aneurysms. MMP-2 and -9 activity was estimated in AAA wall biopsies by gelatin zymography.

Results: patients with a C. pneumoniae-DNA-positive aneurysm wall specimen showed an over-all lower activity of MMP-2 and MMP-9 (pro- and active enzyme) compared to the C. pneumoniae-DNA negative patients. However, there were no statistically significant differences in MMP activity between the two groups of patients with aAAA. Among patients with rAAA both pro-MMP-9 (p=0,026) and active-MMP-9 (p=0.007) were significantly lower in C. pneumoniae-DNA-positive patients compared to C. pneumoniae-DNA-negative patients, whereas there were no significant differences in pro-MMP-2 or active-MMP-2.

Conclusion: this preliminary study does not support the hypothesis that the presence of C. pneumoniae in the AAA wall is associated with increased activity of MMP-2 and MMP-9.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abdominal Wall / microbiology*
  • Abdominal Wall / physiopathology
  • Aged
  • Aged, 80 and over
  • Aortic Aneurysm, Abdominal / complications
  • Aortic Aneurysm, Abdominal / microbiology*
  • Aortic Aneurysm, Abdominal / physiopathology
  • Case-Control Studies
  • Chlamydophila Infections / complications
  • Chlamydophila Infections / microbiology*
  • Chlamydophila Infections / physiopathology
  • Chlamydophila pneumoniae / isolation & purification*
  • Chlamydophila pneumoniae / physiology
  • Female
  • Humans
  • Male
  • Matrix Metalloproteinase 2 / physiology*
  • Matrix Metalloproteinase 9 / physiology*
  • Middle Aged


  • Matrix Metalloproteinase 2
  • Matrix Metalloproteinase 9