Coexistence of mesenteric fibromatosis and Crohn’s disease in a child –a novel case.

Desmoids are benign tumours originating from connective tissue. Their uncontrolled growth can threaten organ function, especially in the abdominal location, when presenting as mesenteric fibromatosis. There have been only a few case reports of the coexistence of mesenteric fibromatosis and Crohn’s disease. All of them were in adults, mostly with potential risk factors for desmoid tumours including female sex, oestrogen intake and abdominal surgery. We present, to our knowledge, the first paediatric case of the coexistence of both conditions. A 15 -year -old boy was operated on due to an obstruction of the gastrointestinal tract. Preoperative radiological examination suggested a tumour causing intussusception. Intraoperatively, a tumour and a significant length of infiltrated ileum were resected. Histopathological examination confirmed a desmoid tumour in the course of mesenteric fibromatosis and Crohn’s disease. The patient has been treated pharmacologically since. Further research is needed to explain their origin and simultaneous appearance in children.