Actinomyces infection (actinomycosis) may create diagnostic conflicts and be confused with malignant neoplasms, especially in the abdomen. The objective of this study was to report a case of abdominal wall actinomycosis with hepatic infiltration, and review the existing evidence. Female patient, 33 years of age, with no surgical history or use of intra-uterine devices. She consulted for abdominal pain and palpable mass at the epigastrium. It was studied with images, which allowed verifying an abdominal wall mass with hepatic fistulae. A broad extirpation of the lesion was performed. The histological study revealed sulfur granules consistent with actinomyces. The patient has evolved satisfactorily, without problems; and is currently in treatment with amoxicillin. We present an unusual case of abdominal wall actinomycosis with hepatic infiltration that resulted in a difficult diagnosis. When a large intraperitoneal mass is found, actinomycosis needs to be included as a differential diagnoses.

KEY WORDS: Actinomycosis; Actinomycosis/surgery; Aerobic actinomyces infection [Supplementary Concept]; Abdominal Neoplasms; Liver Abscess; Pyogenic; Abdominal wall mass.