Fatal infectious mononucleosis is vary rare in the human population. O
nly two case reports of girls suffering an Epstein-Barr virus-associat
ed lymphoproliferation without evidence of an underlying immunodeficie
ncy came to our knowledge. We report on the case of an 11-months-old g
irl with fatal infectious mononucleosis. Some findings allow distinct
delineation from previous reports. Firstly, the present ''pulmonary ly
mphoid hyperplasia'' has been formerly described in patients with HIV
infection exclusively. Secondly, only the EBV surface antigen LMP was
expressed on infected B-cells. The nuclear antigen complex EBNA could
not be demonstrated. Overall, the results suggest a so far unrecognise
d type of EBV-associated lymphoproliferation in a female infant.