Actinomycosis

sulfur granules

Actinomyces israelii - central calcified core - surrounded by branching filaments & PMNs - necrosis, abscess formation & draining sinuses - sulfur granules in other infections such as Nocardia

Actinomyces cause Actinomycosis

- "the Great Pretender" - rare, chronic slowly progressive suppurative granulomatous disease - mimics periapical / periodontal abscess malignant disease, tuberculosis, Nocardiosis - most caused by *Actinomyces israelii* - treatment: antibiotic therapy, surgical debridement - mortality up to 28% depending on site and time to diagnosis

abdominal/pelvic actinomycosis

- 20% of cases - follows abdominal surgery - spread from GI tract or female GU tract - linked to prolonged IUD use result in multiple nodules on the back of a patient with abdominal actinomycosis

thoracic actinomycosis

-spread of actinomycosis to chest wall and ribs - cellulitis with a fistula on the back discharging pus

diagnosis of actinomycosis

medical history fine needle aspiration microscopic exam of discharge culture discharge (<50% culture positive)

actinomycosis

men 20-60 years > women 1:100,000 inhabitants/year endogenous infection break in mucosa types: - cervicofacial (55%) - thoracic (15-30%) - abdominal (20%)

treatment of actinomycosis

prolonged (months) antibiotic treatment - penicillin G --- four weeks of high dose IV --- 3-6 months of oral --- risk of developing penicillin resistance is low - tetracycline - erythromycin - clindamycin incision & drainage & surgical drainage might be required

lumpy jaw syndrome

results from cervicofacial actinomycosis common locations: - angle of mandible (most common) - cheek - chin - TMJ & retro-mandibular area (least common) bone involvement in 10%

Cervicofacial actinomycosis

symptoms: - inflamed indurated mass - submandibular lymphadenopathy - low grade fever (100*F) - drainage milky white with yellow flecks - relapsing/refractory clinical course after short-term antibiotics - bone infection in 12% of cases

formation of dental plaque

this comprises STEP 2 of initial bacterial colonization - early (primary) colonizers --- generally non-pathogenic --- gram-positive cocci and rods : ---- Streptococcus sanguis ---- Streptococcus mutans ---- Actinomyces viscous

causes of cervicofacial actinomycosis

tooth extraction/oral surgery dental caries poor dental hygiene periodontal disease penetrating trauma through oral mucosa

causes of thoracic actinomycosis

- aspiration into the lung - spread of cervicofacial form

Actinomyces israelii

- commensal in the mouth & female GU tract - most important cause of actinomycosis

signs & symptoms of thoracic actinomycosis

- fever, cough, shortness of breath - night sweats, weight loss - chest wall sinus with sulfur granules (26%) frequently wrongly diagnosed : cancer, lung cavitation resembling TB

Actinomyces

- gram positive rods/ branching filaments - soil microorganisms - anaerobes - source of most antibiotics - normal flora, commensals: opportunistic pathogens - cause suppurative granulomatous lesions

complications of pulmonary actinomycosis

- life threatening? - spread into lungs: --- pneumonia --- thoracic draining fistulas - spread to bloodstream - central nervous system involvement --- brain abscess --- meningitis

Actinomyces in oral cavity

- major component of dental plaque - increase in numbers in gingivitis - ? associated with root surface