Mycoplasma spp

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Histopathological findings in the lung of dog infected with Mycoplas spp, showing peribronchiolar lymphoid hyperplasia and interstitial thickening lesions[1]

Mycoplasma spp are a Gram-negative anaerobic hemotropic tick-borne proteobacteria which colonize respiratory epithelium and have involved with respiratory and systemic disease.

Mycoplasmas are the smallest free-living microorganisms capable of autoreplication. They are highly fastidious, difficult to culture, and slow growing[2].

Mycoplasmas are thought to be part of the normal bacterial flora in the upper respiratory tract in dogs

Species which are pathogenic to dogs include:

  • Mycoplasma cynos
  • Mycoplasma canis[3]
  • Mycoplasma haemocanis[4]
  • Mycoplasma haematoparvum
  • Mycoplasma bovigenitalium
  • Mycoplasma edwardii
  • Mycoplasma feliminutum
  • Mycoplasma gateae
  • Mycoplasma spumans[5]
  • Mycoplasma haemobos[6]
  • Mycoplasma haemominutum[7]

Co-infections with Ehrlichia canis, Babesia canis vogeli, Hepatozoon canis are common[8].

These hemoplasms are commonly associated with kennel cough[9], although primary[10] and aspiration pneumonia[11] and granulomatous meningoencephalomyelitis[12] have been reported consequent as primary infections by this organism.

Clinical infections can range from asymptomatic infections to the induction of a severe immune-mediated hemolytic anemia, especially in splenectomised or immunocompromised dogs[13]. Epididymitis and prostatitis have also been reported[14].

The overall importance and distribution of M. cynos, its mechanisms of pathogenicity, and the nature of the immune response to this pathogen are currently unknown. The capacity of M. cynos to persist in the environment is unknown, but other Mycoplasma species can survive for weeks to months outside the host, and the environment could therefore be a source of infection[15].

Little evidence exists to suggest mycoplasma as a trigger of immune-mediated hemolytic anemia in dogs[16].

Diagnosis usually requires ELISA or PCR assays for definitive diagnosis and it can be performed noninvasively with nasal swabs. However, multiple PCR assays may be required because of the large number of Mycoplasma species. Bacterial culture has been the best method for diagnosing a bacterial infection, however the sensitivity of the culture-isolation for Mycoplasma spp is low[17].

Most mycoplasma are sensitive to tetracycline, choramphenicol, tylosin or erythromycin.

References

  1. Hong S & Kim O (2012) Molecular identification of Mycoplasma cynos from laboratory beagle dogs with respiratory disease. Lab Anim Res 28(1):61-66
  2. McAuliffe L et al (2003) Differentiation of Mycoplasma species by 16S ribosomal DNA PCR and denaturing gradient gel electrophoresis fingerprinting. J Clin Microbiol 41(10):4844–4847
  3. Brown DR et al (2012) Genome annotation of five Mycoplasma canis strains. J Bacteriol 194(15):4138-4139
  4. do Nascimento NC et al (2012) Complete genome sequence of Mycoplasma haemocanis strain Illinois. J Bacteriol 194(6):1605-1606
  5. Armstrong D et al (1972) Canine pneumonia associated with mycoplasma infection. Am J Vet Res 33(7):1471–1478
  6. Hii SF et al (2012) Canine vector-borne disease pathogens in dogs from south-east Queensland and north-east Northern Territory. Aust Vet J 90(4):130-135
  7. Obara H et al (2011) A feline hemoplasma, 'Candidatus Mycoplasma haemominutum', detected in dog in Japan. J Vet Med Sci 73(6):841-843
  8. Ramos R et al (2010) Molecular survey and genetic characterization of tick-borne pathogens in dogs in metropolitan Recife (north-eastern Brazil). Parasitol Res 107(5):1115-1120
  9. Greig AS (1954) The Significance Of A Pleuropneumonia-Like Organism In Kennel Cough. Can J Comp Med Vet Sci 18(8):275–279
  10. Rosendal S (1978) Canine mycoplasmas: pathogenicity of mycoplasmas associated with distemper pneumonia. J Infect Dis 138(2):203–210
  11. Tart KM et al (2010) Potential risks, prognostic indicators, and diagnostic and treatment modalities affecting survival in dogs with presumptive aspiration pneumonia: 125 cases (2005-2008). J Vet Emerg Crit Care (San Antonio) 20(3):319-329
  12. Ilha MR et al (2010) Meningoencephalitis caused by Mycoplasma edwardii in a dog. J Vet Diagn Invest 22(5):805-808
  13. Sykes JE et al (2005) 'Candidatus Mycoplasma haematoparvum', a novel small haemotropic mycoplasma from a dog. Int J Syst Evol Microbiol 55:27–30
  14. L'Abee-Lund TM et al (2003) Mycoplasma canis and urogenital disease in dogs in Norway. Vet Rec 153(8):231-235
  15. Nagatomo H et al (2001) Comparative studies of the persistence of animal mycoplasmas under different environmental conditions. Vet Microbiol 82(3):223–232
  16. Warman SM et al (2010) Haemoplasma infection is not a common cause of canine immune-mediated haemolytic anaemia in the UK. J Small Anim Pract 51(10):534-539
  17. Harasawa R et al (1991) Detection of Mycoplasma hyopneumoniae DNA by the polymerase chain reaction. Mol Cell Probes 5(2):103–109