T and B lymphocytes in peripheral blood of children with infectious mononucleosis and tonsillitis.

The occurrence of T and B lymphocytes was investigated in children with infectious mononucleosis. It was shown that T and B lymphocytes participate in the increase in the number of lymphocytes during the acute phase of infectious mononucleosis. The increase in the absolute number of T lymphocytes was statistically significant (p < 0.001) as compared with control healthy children, and non-significant as compared with the absolute number of T lymphocytes in children with tonsillitis. The increased absolute number of B lymphocytes with infectious mononucleosis was statistically significant (p < 0.001) as compared with both control groups. Two of the children had a high percentage of atypical lymphocytes and positive titres of EBV-VAC antibodies, mostly comprising nil type lymphocytes. The findings suggest that infectious mononucleosis has probably a more varied immunological picture in children than in adults.