<prompt> A 40 year old man underwent kidney transplantation. Two month after transplantation,he developed fever and feature suggestive of bilateral diffuse interstitial pneumonia. Which of the following is most likely etiologic agent ?Herpes simplex virusCytomegalovirusEpstein-barr virusVaricella - zoster virus  <response>: It is a case of diffuse interstitial pneumonitis due to CMV.Remember :CMV is the MC infection complicating organ transplantation.CMV is MC cause of intrauterine infection.Risk of post transplant CMV infection is greatest 5-13 weeks after transplant.Infections after Kidney Transplantation 