Actinomyces israelii is a species of Actinomyces and is sometimes known as the “most misdiagnosed disease” since it is often confused with neoplasms. It is a colonizer of the vagina, colon, and mouth. Infection happens through breach of the mucosal barrier during various procedures, aspiration, or pathologies such as diverticulitis.
The chronic phase is also known as the classic phase due to the acute, early phase being commonly missed by health care providers. It is characterized by slow contagious growth that ignores tissue planes and forms a sinus tract that can heal and recur and possibly leading to a densely fibrotic lesion. The lesion is often described as “wooden.” The most common form of actinomycosis is oral-cervicofacial disease. It is characterized by a painless “lumpy jaw”. Thoracic disease is another form of actinomycosis that is commonly misdiagnosed due to it creating a mass that extends to the chest wall. Symptoms include chest pain, fever, and weight loss. Sometimes abdominal disease is associated with actinomycosis. This leads to a sinus tract that drains to the abdominal wall or perianal area.
Pelvic actinomycosis is a rare but proven complication of intrauterine device. In extreme cases pelvic abscess might develop. Treatment is done through antibiotics such as penicillin or amoxicillin for six to twelve months.