[Actinomyces parotid infection after mandibular third molar extraction].

Actinomycosis is currently an uncommonly diagnosed human disease. The disease is a chronic suppurative infection caused by micro-organism from the Actinomyces group, most often Israelii. A patient with cervicofacial actinomycosis generally reports a history of recent dental treatment which, usually, involves extraction of a mandibular molar. The common initial signs and symptoms of infection (such as sudden onset of cervicofacial pain, swelling, erythema, edema and suppuration) can be absent. In this case report a 29-year-old man presented a mass in his left parotid area, 1 week after mandibular molar extraction. Echography and CT scans revealed a parotid abscess area. The needle-biopsy of swelling revealed infection due to Actinomyces. Therapy was started with intravenous cefazolin (fl 1g X 2 in 100 s.s. i.v.) and methylprednisolone (25 mg tablet, 1/die) for 9 days; 14 days after treatment suspension the lesion reappeared with a fistula and a new therapy was given (ceftriaxone 1 g/die and gentamicin 80 mg/i.m. for 3 weeks). To prevent a relapse, the patient received cefalexin 1 gx2/die per os for 4 weeks. After a follow-up of 1 year, the patient was still asymptomatic.