Density of Chlamydia pneumoniae is increased in fibrotic and calcified areas of degenerative aortic stenosis.
BACKGROUND
The process of aortic degeneration associated with calcified aortic stenosis shares many similarities with coronary artery atherosclerosis. Inflammation and infection are involved in both diseases. Chlamydia pneumoniae has been identified in atherosclerotic plaques. However, the studies about the presence of C. pneumoniae in degenerative aortic stenotic valves are not conclusive.


OBJECTIVE
We investigated whether an association exists between the density of C. pneumoniae and fibrosis or calcification in aortic stenosis.


METHODS
Autopsy and surgical specimens were divided into 3 groups: Normal, 11 normal autopsy valves Atherosclerosis, 10 autopsy valves from patients with systemic atherosclerosis and no aortic stenosis and Aortic stenosis, 14 surgical specimens of aortic valves replaced due to aortic stenosis.


METHODS
Heart Institute (InCor), University of São Paulo Medical School.


METHODS
Aortic valves from patients aged 52+/-16 years, 69+/-9 years, and 71+/-8 years.


METHODS
Specimens were evaluated by immunohistochemical technique (to detect C. pneumoniae antigens), in situ hybridization, and electron microscopy (to quantify the density of C. pneumoniae in the valves).


METHODS
The aortic stenosis group was analyzed according to 3 subregions: aortic stenosis-preserved, peripheral preserved regions; aortic stenosis-fibrosis, peri-calcified fibrotic tissue; and aortic stenosis-calcification, calcified nodules.


RESULTS
The median values of C. pneumoniae antigens were 0.09, 0.30, 0.18, 1.33, and 3.3 in groups Normal, Atherosclerosis, Aortic stenosis-preserved, Aortic stenosis-fibrosis, and Aortic stenosis-calcification, respectively. The amount of C. pneumoniae was greater in the Atherosclerosis and Aortic stenosis-calcification groups than in the Normal group (P<0.05). C. pneumoniae was greater in the Aortic stenosis group in the calcified and fibrotic regions than in preserved region (P<0.05).


CONCLUSIONS
An association was found between the higher density of C. pneumoniae and fibrosis/calcification in stenotic aortic valves.
Pierri
Humberto
H
Heart Institute (InCor), University of São Paulo Medical School, São Paulo, SP, Brazil.
Higuchi-dos-Santos
Marilia Harumi
MH
Higuchi
Maria de Lourdes
Mde L
Palomino
Sueli
S
Sambiase
Nadia Vieira
NV
Demarchi
Lea Maria M
LM
Rodrigues
Giselle Helena de Paula
GH
Nussbacher
Amit
A
Ramires
José Antonio Franchini
JA
Wajngarten
Mauricio
M
D000328:Adult; D000368:Aged; D001024:Aortic Valve Stenosis / Q000382:microbiology* / Q000473:pathology; D050197:Atherosclerosis / Q000382:microbiology; D002102:Cadaver; D002114:Calcinosis / Q000382:microbiology* / Q000473:pathology; D002690:Chlamydia Infections / Q000150:complications* / Q000473:pathology; D016993:Chlamydophila pneumoniae / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008854:Microscopy, Electron; D008875:Middle Aged