Actinomycosis

Although rare, a high level of clinical suspicion is needed to diagnose and cure actinomycosis in patients with indolent, unresolving, or relapsing chronic inflammatory disease
Actinomyces are commensals that become pathogenic when the mucosa is breached, and co-infection with other organisms is common
Disease is defined by anatomical location; orocervicofacial disease is the most common, followed by thoracic and abdominopelvic disease
A mass characteristically enlarges across tissue planes and local tissue invasion may lead to the formation of sinus tracts that can spontaneously heal and recur
Actinomycosis often mimics other infections and malignancy—clinically and radiologically
It is generally treated with long term antibiotics, usually penicillin, but surgery may be needed