A 54-year-old man with no previous medical history or toxic habits was admitted to the hospital with a history of periumbilical pain, fever of 38 to 38.5 °C, mesorism and nausea without vomiting.
One day before admission she noticed a mass in the abdomen with increased abdominal pain and fever disappeared.
On physical examination the patient was in good general condition.
Temperature, pulse, blood pressure, head, neck, heart and lungs were normal.
Abdominal examination revealed a hard, left periumbilical mass, tender to constipation measuring 10 cm. There were no signs of peritonitis or hepatomegaly.
The analysis showed 14,000 leukocytes/mm3 with left shift and a ESR of 94 mm/h.
Hematocrit, platelet count, coagulation times, general biochemistry, elemental urine and sediment were normal.
A plain abdominal X-ray showed an increase in hypogastric density and abdominal ultrasound showed a heterogeneous mass of echogenicity in the left rectus muscle.
Abdominal CT scan revealed a mass in the abdominal wall with fixed edges located in the left rectus muscle reaching the greater epipy, without visceral involvement.
The opaque enema demonstrated diverticula in the third portion of the distal colon and no signs of duodenal diverticula or perforation.
A CT-guided needle biopsy of the mass was performed and the histological examination revealed an inflammatory reaction and the presence of Actinomyces colonies.
Treatment was established with oral clindamycin (600 mg/6 hours) for 45 days with good clinical response and disappearance of the mass.
Treatment was switched to Penicillin V orally (800 mg/6 hours) for 1 year.
An abdominal CT performed 6 months later was normal.
During the year of follow-up there was no recurrence of the mass.
