Rare case of an abdominal mass presenting as acute abdomen: torsion of the vermiform appendix.

Torsion of the vermiform appendix is a rarely observed acute abdominal emergency. The clinical manifestations are similar to acute appendicitis. It should be included in the differential diagnosis if a patient presents with intermittent abdominal pain and an acute abdominal emergency. Here, we describe a 4-year-old male patient with a mass located in the right lower abdominal quadrant, whose clinical findings were consistent with an acute abdomen. The gangrenous appendix was found in the pelvic cavity and its stump was twisted clockwise. A 1.5-cm fecalith was detected in the appendix lumen and appendectomy was performed.