Actinomycotic ileal perforation: a case report and literature review

Human actinomycosis is a chronic, slowly evolving infection caused generally by Actinomyces israelii. Diagnosis of abdominal actinomycosis is seldom made preoperatively due to the lack of specific clinical, laboratory and radiological features. This makes the clinical management challenging, furthermore considering the aggressiveness of the infection that often mimics a malignant mass or causes multiple abscesses and a bowel perforation. We present here a case of ileal perforation due to Actinomyces israelii infection and a review of the current literature. An 86-year-old Italian woman with a painful 5 cm in maximum diameter hypogastric swelling was referred to our Unit. Blood tests revealed a mild leukocytosis. Abdominal computed tomography showed a 4 x 5 cm subcutaneous mass with unclear limits in correspondence of the infraumbilical region, with a low enhancement central area and diffusely enhanced peripheral limits. On laparotomy, a great amount of purulent material was drained and perforation of the ileum was evidenced. An ileal resection and a latero-lateral anastomosis were performed. The histological examination of the specimens evidenced an infection by Actinomyces israelii. The postoperative course of the patient was uneventful. Antibiotic therapy with penicillin was started once histological results were obtained. Follow up was performed 3 months after surgery; no recurrences or other complications were observed.