Actinomycosis is caused by an organism, a transitional form between fungi and bacteria. They possess thin cell wall like bacteria and form mycelial branching network resembling fungi. Malnourishment is one of the major cause of the disease.
They are considered as true bacteria, with a superficial resemblance to fungi. Actinomycetes are anaerobic in nature inhabiting the space between the gums and the teeth.
The most common sites of infection are the teeth, lungs and the intestine. It also infects the throat, nose and the stomach.
It is a common disease among animal and human beings, which is chronic and involves the accumulation of immune cells called as macrophages. It is present worldwide, but its occurrence is less in developed countries due to the use of antibiotics.
It is characterized by indurated (hardened) swelling in the connective tissue, pus formation and discharge of particular particles called ‘sulfur granules’. The lesions are often pointing towards the skin, leading to multiple sinuses.
Actinomycosis in human beings is an endogenous infection. The actinomyces species are normally present in the mouth, intestines and vagina as commensals. Trauma (a physical wound on the skin), foreign bodies or poor oral hygiene may favor tissue invasion.
The most common causative agent is Actinomycetes israelii. The disease is a co- operative one. Other pathogenic bacteria may accompany to enhance the pathogenic effect. Fusobacterium, Staphylococci and anaerobic Streptococci are some of them.
Excess weight loss, cough, pain in the chest, fever, etc., are also associated with the infection.
It occurs in mainly 4 clinical forms;
1. Cervicofacial; possess hardened lesions on the cheeks and sub- maxillary region (area below the tongue).
2. Thoracic; lesions are present in the lung that may involve the pleura and the pericardium and spreads outwards through the chest wall.
3. Abdominal; the lesions are usually around the cecum (beginning of the intestine), with the involvement of the neighboring tissues and the abdominal wall. Sometimes the infection might spread to the liver through the portal vein.
4. Pelvic; commonly seen in people using intrauterine devices.
It has also been known to cause inflammation of the gums and plaques leading to root surface caries. The organism infesting the nasal sinuses may ultimately reach the brain causing meningitis.
Laboratory diagnosis is made by;
1. Demonstrating actinomycetes in lesions by microscopy
2. Isolation by culturing methods
3. Sample taken are pus and sputum in case of pulmonary infections.
4. Sulfur granules are demonstrated from the pus
5. The granules are bacterial colonies, which are surrounded by radiating structures resembling a ‘sun ray’.
6. Biochemical reactions are carried out
7. Fluorescent antibody techniques are also utilized.
The disease is common among agricultural workers, mostly men between 10 and 30 years of age.
Maintaining good oral hygiene is the best way to prevent the disease.
Prolonged treatment with penicillin or tetracycline may prove to be effective. Treatment will have to be continued for several months and supplemented by surgery whenever necessary.
Doxycyclin is prescribed for patients with penicillin allergy. A daily dose of sulfamethoxazole (2- 4mg) also seem to be effective for Actinomycosis. nomycosis.