- MULTIFOCAL TO COALESCING LYMPHOPLASMACYTIC AND SUPPURATIVE BRONCHOPNEUMONIA WITH BRONCHIECTASIS
- MYCOPLASMA PULMONIS
- Armed Forces Institute of Pathology
- Mycoplasma pulmonis, regarded as the only clinically significant Mycoplasma sp. in rodents, has an affinity for the ciliated epithelial cells of the respiratory tract, middle ear, endometrium, and synovium, and is the cause of murine respiratory mycoplasmosis (MRM), a naturally acquired chronic disease of laboratory rats. Most rats with clinical disease are co-infected with one or more agents, including Sendai virus, rat coronavirus, Filobacterium rodentium, Streptococcus pneumoniae, Corynebacterium kutscheri, Bordetella bronchiseptica, Klebsiella pneumoniae, and Pasteurella pneumotropica, as part of the chronic respiratory disease (CRD) syndrome. This pathogen has been largely eradicated in laboratory rats, but may still be found in pet and wild rats. Bronchiectasis is a common finding in affected rats - initial infection results in ciliostasis and recruitment of large numbers of neutrophils into affected airways, which in turn damage the elastin in airway wall, resulting in bronchiectasis (a chronic non-healing lesion.) In addition, M. pulmonis' superantigen results in massive BALT hyperplasia.