1. To describe and illustrate the wide spectrum of CT features of abdominopelvic actinomycosis and its possible complications depending on the involvement sites.
2. To highlight the problems in the differential diagnosis of actinomycosis as it often resembles other inflammatory or malignant pathologies.
Actinomycosis is a rare, but serious chronic suppurative bacterial infection most commonly caused by Actinomyces israelii, an anaerobic, Gram-positive, filamentous bacteria, which normally inhabits the flora of the oral cavity, gastrointestinal and genital tract [1,2].
Actinomycosis occurs in the abdominopelvic regions in approximately20% of the cases .
Frequent causative factors [1-4]:
- the integrity disruption of the gastrointestinal mucosa in patients with a history of abdominal surgery, penetrating trauma, accidentally foreign body ingestion, appendicitis, colonic diverticulitis (this allows the spread of actinomyces into the deeper...
Findings and procedure details
Actinomycosis usually presents as [4,5]:
- an inflammatory mass;
-abscess, fistula, draining sinus;
Contrast-enhanced computed tomography allows the assessment of the anatomical location and disease extension, being also useful in monitoring the response to therapy.
The most distinctive CT feature of actinomycosis is the aggressive infiltrative pattern across normal fascial and connective tissue planes- as a result of proteolytic enzymes produced by Actinomyces . Thus, actinomycosis represents one of the most misdiagnosed diseases. Its presentation is more often associated with malignancy, rather than...
The radiologist must be aware of the multiple imaging aspects of actinomycosis and correlate them with the clinical setting of the patient to reach an accurate diagnosis. Considering that actinomycosis could be treated with antibiotic therapy alone, an earlier diagnosis would help limit the extent of tissue infiltration and avoid unnecessary surgery.
Personal information and conflict of interest
D. D. Muntean; CLUJ NAPOCA/RO - nothing to disclose M. O. Anton; CLUJ NAPOCA/RO - nothing to disclose R. Sechel; CLUJ NAPOCA/RO - nothing to disclose
 F Valour, A Sénéchal, C Dupieux, et al. Actinomycosis: etiology, clinical features, diagnosis, treatment, and management Infection and Drug Resistance 2014:7 183–197
 F Acevedo, R Baudrand, LM Letelier, et al. Actinomycosis: a great pretender. Case reports of unusual presentations and a review of the literature. Int J Infect Dis (2008) 12, 358—362
 Lippes J. Pelvic actinomycosis: a review and preliminary look at prevalence. Am J Obstet Gynecol 1999; 180(2 pt 1):265–269.
 SH Heo, SS Shin, JW Kim, et al. Imaging of...