{"id":332,"date":"2023-09-16T22:07:26","date_gmt":"2023-09-16T21:07:26","guid":{"rendered":"https:\/\/microregistrar.com\/?p=332"},"modified":"2023-09-16T22:07:26","modified_gmt":"2023-09-16T21:07:26","slug":"capnocytophaga-spp","status":"publish","type":"post","link":"https:\/\/microregistrar.com\/?p=332","title":{"rendered":"Capnocytophaga spp."},"content":{"rendered":"\n

Capnocytophaga genus belongs to the family Flavobacteriaceae.
There are >9 species of Capnocytophaga, which can be divided into two groups \u2013 resident of human mouth flora and dog\/cat mouth flora.<\/p>\n\n\n\n

Species found in the human oral cavity<\/strong><\/td>C. gingivalis<\/em>, C. granulosa<\/em>, C. haemolytica<\/em>, C. leadbetteri, C. ochracea<\/em> and C. sputigena<\/em><\/td><\/tr>
Species found in dog\/cat oral cavity<\/strong><\/td>C. canimorsus <\/em>and C. cynodegmi<\/em><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Risk factors for Capnocytophaga infection:<\/h4>\n\n\n\n
    \n
  • Dog bite, cat-scratch<\/strong><\/li>\n\n\n\n
  • immunocompromise state, including chemotherapy, biologics and HIV<\/strong><\/li>\n\n\n\n
  • asplenia<\/strong><\/li>\n\n\n\n
  • cirrhosis<\/li>\n\n\n\n
  • heavy alcohol use<\/strong><\/li>\n\n\n\n
  • diabetes<\/li>\n<\/ul>\n\n\n\n

    Disease caused by Capnocytophaga:<\/h4>\n\n\n\n
      \n
    • Bacteraemia<\/li>\n\n\n\n
    • Endocarditis, Pericarditis<\/li>\n\n\n\n
    • Keratitis, endophthalmitis, meningitis, intracranial abscess<\/li>\n\n\n\n
    • Chest infection, empyema, mediastinal abscess<\/li>\n\n\n\n
    • Iliopsoas abscess, peritonitis<\/li>\n\n\n\n
    • Osteomyelitis<\/li>\n\n\n\n
    • chorioamnionitis, neonatal sepsis. etc.<\/li>\n<\/ul>\n\n\n\n

      C canimorsus infection may result in septic shock, fever, disseminated purpura\/purpura fulminans, acute renal failure, and confusion.<\/p>\n\n\n\n

      Pathogenesis:<\/h4>\n\n\n\n

      Capnocytophaga can evade the immune system, at least at the early stages of infection. These properties have been observed in various strains \u2013<\/p>\n\n\n\n

        \n
      • Failure to interact with toll-like receptor 4,<\/li>\n\n\n\n
      • Prevent the development of inflammatory responses and<\/li>\n\n\n\n
      • Resistance to complement-mediated killing and phagocytosis by polymorphonuclear cells.<\/li>\n<\/ul>\n\n\n\n

        Laboratory identification<\/h4>\n\n\n\n
          \n
        • Slow-growing, capnophilic, facultative anaerobe.<\/li>\n\n\n\n
        • Grow on blood and chocolate agar but not MacConkey agar.<\/li>\n\n\n\n
        • Thin, long, often fusiform Gram-negative rod. However, it could be pleomorphic in old cultures.<\/li>\n\n\n\n
        • Oxidase +ve, Catalase +ve, indole -ve, urease -ve,<\/li>\n\n\n\n
        • Identification confirmation \u2013 16S rRNA, MALDI-ToF<\/li>\n<\/ul>\n\n\n\n
          \n
          \"\"<\/figure>\n\n\n\n
          \"\"<\/figure>\n<\/figure>\n\n\n\n

          <\/p>\n\n\n\n

          Antimicrobial susceptibility:<\/h4>\n\n\n\n

          Capnocytophaga spp produces various beta-lactamases \u2013 TEM-17, CSP-1, CfxA, conferring resistance to penicillins, cephalosporins, aztreonam and monobactams.<\/p>\n\n\n\n

          Beta-lactamase production is rare in C canimorsus.<\/strong><\/p>\n\n\n\n

          Betalactam-betalactamse combinations (pip-tazobactam, coamoxiclav), and carbapenems are active.<\/p>\n\n\n\n

          Antibiotics that are active<\/strong><\/td>Betalactam-betalactamse combinations (pip-tazobactam, coamoxiclav),
          Carbapenems,
          Clindamycin,
          Linezolid,
          Doxycycline,
          Chloramphenicol<\/td><\/tr>
          Antibiotics not active<\/strong><\/td>Polymyxin,
          Fusidic acid,
          Fosfomycin,
          Colomycin,
          Trimethoprim<\/td><\/tr>
          Antibiotic with variable activity<\/strong><\/td>Erythromycin,
          Rifampicin,
          Quinolone,
          Cephalosporins,
          Metronidazole,
          Vancomycin,
          Aminoglycoside,
          Aztreonam.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          \n