Aim: Cytomegalvirus (CMV) gastroenteritis is rarely described in immunocompetent children. We describe here an immunocompetent 1-year-old boy with CMV-associated protracted diarrhoea and discuss the pathogenesis of CMV infection of the gastrointestinal tract.
Methods: Immunohistochemical study was performed using a gastric and duodenal tissue of this patient. Furthermore, the detection of CMV-DNA in stool and urine samples was performed by polymerase chain reaction method.
Results: CMV infection was proven by the detection of CMV-DNA in stool and urine samples and CMV-positive cells in the immunoperoxidase preparation from gastroduodenal biopsy. The biopsy specimens showed severe chronic active gastroduodenitis with numerous CD3+ T cells and CD68+ macrophages.
Conclusions: We speculated from these findings that CMV invasion of the mucosal layer induced an intense immune response characterised by massive infiltration of activated T-cells and macrophages in this patient. Although the pathogenesis of CMV-associated gastroenteritis in immunocompetent hosts remains generally unknown, immune mechanism may play some roles in generating the chronic inflammatory lesions.