Actinomyces are Gram positive, filamentous bacteria 

-Most common causative agent is Actinomyces israelii 

-Common precipitating factors are dental diseases or procedures, Intrauterine contraceptive use 

Symptoms & Signs 

Acute inflammation followed a chronic, indolent phase with indurations

Symptoms & signs depend on the site of infection 

Oral-Cervicofacial disease (most common): pain, fever, soft-tissue swelling, abscess; the most common location is on the jaw angle 

Thoracic disease: Fever, chest pain, weight loss

Abdominal/Pelvic disease: abdominal pain, weight loss, fever, abnormal vaginal discharge


Histology: Central necrosis consisting of neutrophils and sulfur granules 

Culture: Gram-positive filamentous bacteria


Penicillin G (drug of choice), Ampicillin, Doxycycline