Primary mesenteric lymphangioma in a young adult with intestinal malrotation and 'counter-clockwise barber pole sign'.

Mesenteric lymphangiomas are uncommon benign lesions that usually occur in isolation but rarely may be associated with gastrointestinal (GI) malrotation. Malrotation may cause chronic and recurrent volvulus leading to chronic venous congestion and lymphatic engorgement. Interference with lymphatic drainage may result in formation of a lymphangioma or a chylous mesenteric cyst. In our case, mesenteric lymphangioma was present with partial malrotation of small and large bowel. There was no radiological and surgical evidence of volvulus, favouring the hypothesis that lymphangioma may be a primary congenital association of GI malrotation. Another interesting finding was the counter-clockwise twisting of the superior mesenteric vein around the superior mesenteric artery which has been reported only seven times in the literature.