Torsion and infarction of a large pediatric mesenteric inflammatory myofibroblastic tumor: a case report

Inflammatory myofibroblastic tumor (IMT) is an uncommon intermediate-grade myofibroblastic neoplasm. It rarely arises from the mesentery in children. Infarction secondary to torsion is an exceptionally rare complication that can cause acute abdominal symptoms, mimicking intra-abdominal sepsis or malignancy. A 2½-year-old child from Yemen presented with a five-day history of progressive abdominal pain, distension, vomiting, and high-grade fever. Imaging revealed a large, well-defined mesenteric mass compressing adjacent bowel loops. Laparoscopy showed a necrotic, inflammatory mass with dense adhesions and purulent exudate, prompting conversion to open laparotomy. A pedunculated mass arising from the jejunal mesentery was twisted at its vascular pedicle, resulting in torsion and gangrenous infarction. Complete excision was performed, preserving bowel integrity. Histopathology demonstrated a spindle-cell neoplasm with extensive hemorrhagic and ischemic changes. Immunohistochemistry was positive for vimentin and desmin, and negative for ALK1, SMA, and other markers, confirming IMT with infarction. The postoperative course was uneventful, and the child remained asymptomatic at six-month follow-up. Mesenteric IMT should be considered in the differential diagnosis of pediatric mesenteric spindle-cell lesions. Torsion of a pedunculated IMT can lead to infarction and acute abdomen, closely resembling malignant or infectious intra-abdominal processes. Immunohistochemistry is essential to distinguish IMT from other spindle-cell tumors such as myofibroma, desmoid fibromatosis, or sarcoma. Complete surgical excision is curative in most cases, with an excellent prognosis following full resection.