Microbiology
Summary
Actinomyces israelii, a gram-positive, obligate anaerobic branching rod, is part of the normal flora of the oral cavity. Infections with this bacteria are often associated with jaw trauma, and these infections are referred to as cervicofacial actinomycosis.
Cervicofacial actinomycosis has a slow progression, beginning with a non-tender jaw lump and eventually forming an abscess. Subsequently, sinus tracts form, which drain the infection site through the skin, producing a thick yellow pus containing characteristic yellow sulfur granules. The treatment for Actinomyces infections typically involves penicillin G and, in more complicated cases, surgical drainage might be needed.
Lesson Outline
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FAQs
A. israelii is a gram-positive branching rod known for its ability to cause infections such as cervicofacial actinomycosis. These bacteria are obligate anaerobes, meaning that they only thrive in environments without oxygen. Cervicofacial actinomycosis is an infection that often occurs in the facial and neck regions, typically resulting from jaw trauma, dental work, or other facial injuries that introduce the bacteria into the soft tissues.
A. israelii infections often present with localized swelling, inflammation, and tissue destruction. Sinus tracts are a common clinical finding in such infections. These are abnormal channels that extend from the site of infection to the skin surface, allowing pus to drain from the infected area. In the case of cervicofacial actinomycosis, these tracts are often found on the face or neck.
Yellow sulfur granules are small, yellowish granules found in the pus draining from sinus tracts in A. israelii infections. They consist of bacterial colonies and host inflammatory cells, protein, and other debris produced by the body's immune response. These granules are a characteristic feature of actinomycosis and can help in the diagnosis of infection.
The treatment of choice for A. israelii infections is IV penicillin G. The course of treatment may last for several weeks to months, depending on the severity of the infection. Alternative antibiotics, such as tetracycline and clindamycin, can be used for patients with a penicillin allergy. In some cases, surgical drainage of the infected area may be necessary to remove pus and alleviate symptoms.
Dental work can lead to A. israelii infections, as the bacteria are commonly found in the oral cavity. Invasive dental procedures, extractions, or oral trauma may introduce the bacteria into the deeper tissues, resulting in infection. To prevent these infections, maintaining good oral hygiene is essential. Proper dental care, including regular dental visits, and addressing any dental issues promptly can help minimize the risk of developing A. israelii infections.
