Format

Send to

Choose Destination
See comment in PubMed Commons below
Tuberculosis (Edinb). 2008 Jul;88(4):295-306. doi: 10.1016/j.tube.2007.12.003. Epub 2008 Mar 5.

Disseminated disease severity as a measure of virulence of Mycobacterium tuberculosis in the guinea pig model.

Author information

1
Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523-1682, USA. sivagiri@colostate.edu

Abstract

Virulence is the measure of pathogenicity of a microorganism as determined by its ability to invade host tissues and to produce severe disease. In the low-dose aerosol guinea pig model the virulence of multiple strains of Mycobacterium tuberculosis was determined by measuring time of survival, bacterial loads in target organs, and the severity of pulmonary and extra-pulmonary lesions. Erdman K01, CSU93/CDC1551 and HN878 had shorter survival times compared to the common laboratory strain H37Rv. After 30 days of the infection bacilli had disseminated from the lungs resulting in microscopically visible lesions in peribronchial lymph nodes, peripancreatic lymph nodes, spleen, liver, pancreas, adrenal and heart. The extent of the lesion necrosis paralleled virulence when survival times were used as a measure as Erdman K01 and the two clinical isolates caused more necrosis and resulted in sooner death in infected animals than the H37Rv. The extent of extra-pulmonary lesion necrosis was a better predictor of virulence than the number of viable bacilli in the tissue. Overall, this study emphasizes the point that extra-pulmonary disease is a prominent feature of the guinea pig model and dissemination to organs not normally assayed such as the heart and adrenal glands should be taken into account in the assessment of the disease process.

PMID:
18321783
PMCID:
PMC2572689
DOI:
10.1016/j.tube.2007.12.003
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center