Etiology:  Klebsiella pneumoniae is a Gram-negative facultatively anaerobic non spore-forming rod.  K. pneumoniae has not been recognized as a primary pathogen.

Incidence:  The incidence of infection is rare.

Transmission:  Transmission is fecal-oral or from direct contact.  K. pneumoniae may be spread to animals by humans.

Clinical Signs:  Immunocompetent animals do not usually display clinical signs.  K. pneumoniae is an opportunistic organism and infection may occur when there is an overgrowth of bacteria due to disruption of the gut flora in immunocompromised rats.  Signs may include poor body condition, ruffled hair coat, abscesses, urogenital tract infections and sometimes mild rhinitis.

Pathology:  Lesions are usually suppurative.

Diagnosis:  Diagnosis of Klebsiella pneumoniae is made by culture.