A20. The most frequent pyogenous infections

Page created on October 21, 2021. Not updated since.

Pyogenic infections are those which cause the formation of pus. Many bacteria are pyogenic, including staphylococcus aureus, streptococci, e. coli, etc.

It’s difficult to know what they expect with this topic, but I’ll go with what Lee assumed should be included. Cellulitis and fasciitis belong to dermatology, but abscesses belong to surgery.



An abscess is an enclosed collection of pus within tissue, usually caused by bacterial infection. They may develop from local invasion from nearby infections, from haematogenous spreading, or from direct entry from outside (from trauma). Abscesses are more common in immunocompromised, diabetics, and IV drug users. There are many types of abscesses, as they can occur almost anywhere:

  • Skin abscess and perianal abscess
  • Intraabdominal abscess
  • Brain abscess
  • Lung abscess
  • Peritonsillar abscess
  • Liver abscess
  • Psoas abscess (in the iliopsoas muscle compartment)
  • Periappendiceal abscess
  • Etc.

Clinical features and diagnosis

Abscesses may cause symptoms of infection, like fever, malaise, and chills, as well as local pain. Labs may show evidence of infection. For internal abscesses, CT is important for diagnosis and to guide drainage. Skin abscesses are diagnosed clinically.


Most abscesses require both antibiotics and drainage to resolve. Drainage may be transcutaneous or surgical. Often, a drain is left in the abscess for a few days to allow for complete drainage. In most cases, the pus should be cultured to guide antibiotic therapy. One notable exception is lung abscess however, which often resolves with antibiotics alone.

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A19. Methods of local anesthesia (conduction anesthesia, regional anesthesia)

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A21. The use of antibiotics in surgery and ways of administration.

Parent page:
Surgery – Traumatology

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