Clinical features and computed tomography (CT) findings in abdominal actinomycosis: A retrospective review

Abstract

Background: Actinomycosis refers to a rare chronic disease and presents diagnostic challenges due to its similarity to malignancies and other infections. Early recognition and appropriate antibiotic therapy are crucial for effective treatment. Surgical intervention may be necessary to manage abscesses or remove infected tissues.

Objective: To study the key symptoms presentation and the characteristics observed in computed tomography (CT) scans to aid in the diagnosis of abdominal actinomycosis. This aims to contribute to more precise decision-making in selecting appropriate and beneficial treatment approaches for patients.

Materials and methods: A retrospective analysis of abdominopelvic actinomycosis cases (n=13) treated surgically at Siriraj Hospital from January 2007 to June 2022 was conducted. Medical records, including clinical, pathological, microbiological, and therapeutic data, were comprehensively analyzed. Subjects, with an average age of 52.3 years (range: 29–76), underwent CT image interpretation by two experienced radiologists in an independent manner.

Results: CT manifestations, with abscess formation being predominant (n=8, 61.5%). Other findings included fistula tract formation (n=3, 23%), soft tissue mass mimicry (n=2, 15.3%), and the presence of foreign bodies (n=4, 30.7%). Chief complaints prompting hospital visits encompassed palpable mass, abdominal pain, lower gastrointestinal tract bleeding, chronic diarrhea, and frequent urination.

Conclusion: Abdominal actinomycosis warrants consideration in the differential diagnosis for abdominal CT-detected masses or abscesses. Knowledge of CT features in actinomycosis infection; fistula formation, retained foreign body in the lesion helps radiologists considering this infection in differential diagnosis that guides the proper treatment planning.