Primary actinomycosis of the greater omentum

Abdominal actinomycosis masquerading as an omental tumor in a 12-year-old female

We herein report a case of abdominal actinomycosis in a 12-year-old girl in whom an omental primary tumor was suspected before surgery. The patient began to experience intermittent lower left abdominal pain. Abdominal computed tomography (CT) scans were inconclusive at this time, but 6 months later, CT and magnetic resonance imaging (MRI) examinations showed a 7-cm, tumor-like lesion in the left abdominal cavity; malignancy could not be ruled out. The tumor, which originated in the omentum and adhered strongly to the left abdominal wall, was resected along with approximately 90 % of the omentum, the peritoneum in contact with the mass, and the posterior layer of the rectus abdominal sheath, under suspicion of a malignant tumor. However, omental actinomycosis was the final pathological diagnosis. The patient's antibiotic treatment was changed to a penicillin-series oral antibiotic to prevent recurrence of the actinomycosis. The patient was discharged from our hospital 16 days after the first surgery, but she developed three episodes of ileus; the first two required surgery. The patient has had no further recurrences of actinomycosis or postoperative ileus 20 months after discharge.

Abdominal actinomycosis: a rare complication after laparoscopic gastric bypass

A 33-year-old, morbidity obese woman underwent a laparoscopic Roux-en-Y gastric bypass in November 2004. She presented 18 months later with a history of recurrent pain in the upper region of the abdomen and severe vomiting. Radiologic and endoscopic evaluations revealed wall thickening in the transverse colon and a solid tumor near the liver. Therefore, a sonography-guided biopsy of the tumor was performed. Cytopathological examination revealed actinomycosis. Thus, therapy with penicillin was started, after which the parameters associated with the infection decreased. The symptoms persisted, however, and the decision was made to operate on the patient to resect the abdominal masses. Nearly 90% of the masses could be removed. Histological analysis showed a fibro-productive inflammation with an actinomycotic etiology. Antibiotic therapy with penicillin was continued for 6 months. Actinomycosis must be considered in the differential diagnosis of patients with abdominal mass, wall thickening of the intestine, and other such symptoms, including abdominal pain following bariatric surgery, even many years after the intervention.