Klebsiella species

Prevalence
  • Common in laboratory animals, rare in immunocompetent animals
  • Incidence of infection – moderate, naturally occurring infectious diseases - infrequent
Significance
  • Increasingly relevant due to its proneness to obtain antibiotic resistance
  • As immunocompromised animals may develop clinical signs related to Klebsiella caused disease, research in relation to these diseases should use animal models that are free of the organism
Disease
  • Gram-negative rod-shaped proteobacteria
  • Most commonly isolated from the gut and nasopharynx
  • Clinical signs – Even though immunocompetent animals don’t usually show clinical signs and reports of disease are rare, Klebsiella spp. are opportunistic pathogens which may cause infection in conjunction with an overgrowth of bacteria due to gut flora disruption in immunocompromised mice. Signs include:
    • Poor body condition, ruffled coat, otitis media, urogenital tract infections, pneumonia, abscesses, or sepsis
    • Other lesions include - subcutaneous, intra-abdominal and liver abscesses, keratoconjunctivitis, Harderian gland adenitis, meningitis, and infections of the oral cavity, maxilla and salivary glands
Transmission
  • May be transmitted through the faecal-oral route or by direct contact
  • K. oxytoca may also be transmitted from humans to animals
Diagnosis
  • Preferred – Bacterial culture of faeces and/or nasotracheal wash onto CHROMagar (Microbact 24E biochemical test is performed to differentiate between species)
  • PCR of infected tissue or suspected cultures
  • Generally, no histopathology - lesions in susceptible mice are usually suppurative
Strains
  • Strains vary in virulence.
Duration
  • Animals often carry the pathogen in the gut, on the skin and in the nasopharynx without displaying any symptoms and remains disease free.
Durability
  • Capacity to form biofilms that protect them from some sterilization methods (unless mechanically disrupted)
  • Propensity to acquire antibiotic resistance
  • Susceptible to most common disinfectants used in animal facilities
Screening
  • Included in Routine Monitory microbiological tests.
Prevention and Control
  • Rederivation through embryo transfer or hysterectomy.
 
Reading
  • M. Thangapandiyan, S.P. Preetha, S. Suresh Kannan, & T. Mohanapriya. Occurrence of the SHV GENE and Antibiogram of Klebsiella pneumoniae Infection in Swiss Albino Mice Colony. IRA-International Journal of Applied Sciences, 2016, 3(3), ISSN 2455-4499
  • Andre Bleich, Petra Kirsch, Hany Sahly, Jim Fahey, Anna Smoczek, Hans-Jürgen Hedrich, & John P Sundberg. Klebsiella oxytoca: opportunistic infections in laboratory rodents. Laboratory Animals, 2008, 42: 369-375
  • Dean H. Percy & Stephen W. Barthold. Pathology of Laboratory Rodents and Rabbits (Third Edition), 2007
  • Régis Tournebize, Bich-Thuy Doan, Marie-Agnès Dillies, Sabine Maurin, Jean-Claude Beloeil, & Philippe J Sansonetti. Magnetic resonance imaging of Klebsiella pneumoniae-induced pneumonia in mice. Cellular Microbiology, 2005, 8(1): 33-43
  • University of Missouri, Research Animal Diagnostic Laboratory website: http://radil.missouri.edu
  • Infectious Diseases of Mice and Rats, National Research Council, 1991