Non-traumatic Internal Oblique Muscle Hematoma.

A 69-year-old obese man (body mass index, 30.3) presented with acute left abdominal pain after severe coughing. He had no history of direct abdominal trauma. He was not receiving anticoagulant therapy. A physical examination showed a smooth painful mass on his left abdominal wall. The laboratory findings were a platelet count of 196,000/mm3 and a normal range of coagulability. Ultrasonography revealed a hypoechoic mass in the left lateral abdominal wall (Picture 1a). Unenhanced computed tomography showed a distensible high-density mass consisting of fluid-fluid levels in the left internal oblique muscle (Picture 1b and c), and the transverse abdominal muscle was intact. Extravasation could not be evaluated because of his renal dysfunction. He was diagnosed with internal oblique muscle hematoma and was conservatively treated. Ecchymosis presented three days later on his left lateral abdomen (Picture 2). Spontaneous abdominal wall hematoma is considered to occur as a non-traumatic injury to vessels or muscles of the abdominal wall and has several risk factors, including overcontraction due to coughing or vomiting and weakness of the vessel wall as a result of hypertension, arteriosclerosis, obesity or pregnancy (1,2). In spontaneous abdominal wall hematoma, a rectus sheath hematoma has been well described; however, an oblique muscle hematoma is very rare (3). Conservative treatment is acceptable for most patients, and surgical treatment is limited to certain conditions, such as cases of hematoma progression, rupture into the peritoneal cavity, or infection. Several recent reports have demonstrated that angiography with embolization can control bleeding and avoid surgical intervention (1,4). If surgical or angiographic treatment must be performed, then the extravasations should first be revealed by enhancement, even in patients with renal dysfunction, such as the present case, while considering the possible presence of hemocatharsis.

Picture 1.

Picture 2.

The authors state that they have no Conflict of Interest (COI).