MixedActinomyces israeliiandAggregatibacter actinomycetemcomitansinfection causing empyema necessitatis and multiple skin abscesses in an immunocompetent patient

Abstract

A 45-year-old- man presented with left chest wall pain, swelling and cough. Over a 2-month period he developed abscesses in the right foot, right anterior thigh, left buttock and left chest. Incision and drainage of the soft tissue abscesses and video-assisted thoracoscopic surgery to drain the loculated empyema contiguous with the chest wall abscess were performed as surgical management. Gram stain showed beaded Gram-positive rods and the culture initially grew Aggregatibacter actinomycetemcomitans and Eikenella corrodens. Pathological evaluation of the pleura showed sulfur granules and organisms consistent with Actinomyces spp. on Gomori methenamine silver stain; Actinomyces israelii was recovered in culture with extended incubation. The patient was treated for 3 weeks with ceftriaxone and oral metronidazole, followed by oral amoxicillin. Culture of A. actinomycetemcomitans with other findings consistent with actinomycosis warrants 6–12 months of antibiotic therapy.

Aggregatibacter actinomycetemcomitans Causing Empyema Necessitans and Pyomyositis in an Immunocompetent Patient

“…Infection occurs via hematogenous dissemination or aspiration into the respiratory tract with direct invasion of surrounding structures in the setting of dental disease [ 5 , 6 , 7 , 9 ]. It often causes coninfection with Actinomyces and is known to cause empyema necessitans [ 6 , 8 - 10 ].…”

“…It has frequently been reported to be resistant to vancomycin and clindamycin. Previously published case reports have shown successful treatment of invasive infection caused by this pathogen with intravenous ceftriaxone or penicillin followed by oral amoxicillin or with oral amoxicillin alone [ 5 - 8 , 10 ]. It is recommended to obtain susceptibility testing in order to better guide antibiotic selection.…”