Abscess formation of abdominal wall mimicking lymphoma due to Morganella morganii infection in a prepubescent children

Morganella morganii infection mainly occurred in elderly people and immunocompromised patients.However, the abdominal wall abscess due to Morganella morganii infection in prepubertal children hasn't been documented.Our presented case is a 4-year-old male patient with a 1 month history of left lower quadrant abdominal mass. Preoperative ultrasonography showed a hypoechoic, heterogeneous mass and the mass wasn't just confined to the abdominal wall, mimicking lymphoma. On CDFI, an image of highly vascularized mass was demonstrated. The patient underwent lump resection of abdominal wall.Postoperative process was uneventful except intermittent haematuria, and bladder sludge and urethral calculus on ultrasonography.By symptomatic treatment, haematuria disappeared and urethral calculus and bladder sludge decreased. Then the patient discharged home. Postoperative histopathology and immunohistochemistry were suggestive of abscess formation and Morganella morganii was isolated finally from the aspirated pus. Therefore, although the abdominal wall abscess due to Morganella morganii infection is rare, it should not be absent in the differential diagnosis of abdominal wall masses in children. Imaging features of abdominal wall masses should closely integrate the pertinent clinical history.