Cytomegalovirus-associated intussusception with florid vascular proliferation in an infant

Cytomegalovirus (CMV)-associated intussusception has been reported rarely; there have been three case reports in immunocompetent and human immunodeficiency virus-infected infants.1"3 None of these three case reports described a detailed histologic pattern, except ischemic necrosis of the small intestine due to a prolonged clinical history and delayed surgery. DISCUSSION CMV infection occurs throughout the gastrointestinal tract, with ulceration as the most common morphologic change.4,5 Gastrointestinal CMV infection presenting as a polyp is unusual, and only a few cases have been reported.2,6,7 The lesions exhibit features like those of inflammatory or juvenile polyps, including surface ulceration, distention and shape irregularity of the crypt glands, and granulation tissue-type small capillary proliferation with inflammatory cell infiltration. [...]based on the dominant histologic pattern in the biopsy, CMV-associated polyps could be variably diagnosed as inflammatory fibroid polyps, inflamed hyperplastic polyps, inflammatory myofibroblastic tumors or even vascular tumors, etc.2,6,7 In our case, the polyp had histologic features reminiscent of a juvenile polyp. Recurrent intussusception produces variable nonspecific histologic changes, including disorganization of the muscularis propria, fusion of the muscularis mucosae with the muscularis propria, focal submucosal fibrosis, telangiectasia, fibrous serosal adhesion, localized mucosal hyperplasia, etc.8 In addition, florid small vascular proliferation has been reported, which may be so pronounced as to raise the possibility of primary vascular neoplasm.9,10 Although the mechanisms underlying the development of such vascular lesions are difficult to ascertain, repeated mechanical forces applied to the bowel wall during long-term mucosal prolapse associated with intussusception trigger angiogenesis, resulting in an exuberant form of highly vascularized granulation tissue.