[Severe Epstein-Barr virus infection in an infant].

A 11 month-old boy, without any informative familial pedigree, was admitted for peritonitis after intestinal perforation, associated with signs of pseudolymphoma and histiocytic activation. He developed later unexplained gastrointestinal bleeding and interstitial pneumonitis, which spontaneously improved. All infectious and immunologic studies were negative. Epstein-Barr Virus was found in throat, lungs and blood, whereas the specific antibodies production was delayed. No abnormality was detected 18 months later, except for a disappearance of vaccinal antibodies.