Positive CMV IgG does n't necessarily mean that it is reactivation of latent infection because of the possibility of reinfection of different strain .
It is practically achieved by colonoscopy or sigmoidoscopy tissue sampling and pathological evidence of CMV infection under microscope .
Positive CMV   does n't necessarily mean that it is reactivation of latent infection because of the possibility of reinfection of different strain .
It is practically achieved by colonoscopy or sigmoidoscopy tissue sampling and pathological evidence of CMV infection under microscope .