- Patients with actinomycosis are generally normal hosts
-
NOT immunocompromised. It is an uncommon infection in transplanted
patients.
It is not an opportunistic infection. It is due to aspiration of organisms
from oral cavity. Patients with a predisposition to aspiration e.g. seizure disorder, mental retardation, episodes of unconsciousness,
alcoholism etc are
more prone to develop infection. This statement refers to pulmonary infection.
Method of invasion and spread in humans
- Actinomyces are normal inhabitants of the oral cavity.
- Gingivitis and caries of teeth contain aerobic and anaerobic bacteria.
They provide a milieu suitable for growth of Actinomyces.
- If there is an injury to jaw they are able to invade the soft tissue of
Jaw and progress.
Human defense
Pathology
Necrotizing inflammation with abscess formation.
Diagnosis
- They must be cultured strictly in anaerobic environment for at
least one week.
- In only 50% of cases organisms are successfully cultured.
- The other concomitant organisms perhaps work in synergy to produce the
necessary anaerobic environment for Actinomyces.
- In actinomycosis there are sulphur granules which are ball-shaped bacterial colonies, gram-positive, with club-shaped ends of radially oriented filaments.
Therapeutic strategy
- Actonomycosis needs to be treated with Penicillin
- For protracted period of
time.
Prevention
- It is not a contagious infection. These organisms are normal inhabitants of the oral cavity.
- Proper care of Teeth and Gingiva should prevent a situation favoring
growth of these organisms
Clinical infections with these organisms
Oral cervical disease, thoracic disease, mass lesions, pneumonia with or without
pleural involvement, abdominal disease-abscess or mass secondary to disruption of the
bowel mucosa, pelvic disease, CNS disease - rare, bone and soft tissue.
- Cervicofacial area 55%
- Abdominopelvic region 20%
- Thorax 15% :The indolent infection progresses to necrotizing pneumonia.
If untreated abscesses develop with extensive parenchymal destruction. Predilection
to bases and peripheral portion of lungs is due to aspiration
as the initiating process. Disease spreads through pleura to chest wall as
in our patient. In untreated cases sinus tracts can form with characteristic
sulfur granules. Think Actino whenever a lesion crosses fissure or pleura,
extends to contiguous mediastinum or chest wall.
- Rare pelvic form has been associated with Intrauterine contraceptive devices.