Morphological and cytochemical characteristics of atypical mononuclear cells in the blood of patients with the syndrome of infectious mononucleosis caused by Epstein-Barr virus.

On the basis of their origin and morphologic and cytochemical characteristics, atypical mononuclear cells (AMNC) in the peripheral blood of patients with the syndrome of infectious mononucleosis caused by the Epstein-Barr (EB) virus can be classified into three groups, from I to III. The AMNC groups I are the most numerous (76.36% +/- 2.50%). A larger part of these cells have the characteristics of more or less altered lymphoblasts and the smaller part of large pyroninophilic cells and "reactive immunoblasts", and meant to have developed from T lymphocytes. These are the most numerous in the acute phase of the disease, which correlates with the most significant increase of T lymphocytes values. A very high percentage (84.00% +/- 7.30%) of the AMNC group I contains acid phosphatase isoenzyme 3 and acid non-specific esterase (82.43% +/- 7.76%), a considerable percentage of beta-glucuronidase (58.75% +/- 13.99%), and acid phosphatase isoenzyme 1 (51.20% +/- 10.81%). A small percentage of these cells contains acid phosphatase isoenzyme 5 resistant to the action of L+tartaric acid. In 39.04% +/- 8.72% of the lymphocytes in the peripheral blood of the examined patients and in the two thirds and nearly three fourths of the AMNC group I, the presence of acid phosphatase manifests itself in the form of scattered granules. The positive reaction to non-specific esterase (pH 7.8-8) in 39.72% +/- 8.44% lymphocytes of the peripheral blood of the patients and in 59.26% +/- 10.09% of the AMNC group I manifests itself in the form of scattered granules.(ABSTRACT TRUNCATED AT 250 WORDS)