[Monitoring lymphocyte activity in the peripheral blood of patients after bone marrow transplantation]

After bone marrow transplantation serious complications develop which may limit the success of this therapeutic method. One of the early complications is an acute graft versus host reaction. The objective of the investigation was to evaluate the relationship between the number of active lymphocytes in the patient's blood stream after bone marrow transplantation and the development of an acute graft versus host reaction or rejection of the graft, and thus contribute towards prediction or diagnosis of these complications.

In 14 patients with acute myeloid leukaemia (3), acute lymphatic leukaemia (1), chronic myeloid leukaemia (6), myelodysplastic syndrome (2) and aplastic anaemia (2) bone marrow was transplanted: the donor was in all instances a HLA identical sibling. However, only 11 patients were evaluated. In the latter changes in the number of circulating active lymphocytes were assessed: their activity was evaluated from nucleolar characteristics expressed by RNA synthesis. Their values at the time of the acute graft versus host reaction (GVHD) varied between 7.4% and 17.3%; at the time when these patients were free from complications they were 2.2%-6.0% (the difference is at the borderline of significance). In 8 patients the rise of active lymphocytes preceded the manifestation of the graft versus host reaction by 3-7 days. At the time of infectious complications after bone marrow transplantation (temperatures of obscure origin, herpetic infections, varicella, adenoviral infections) the number of active lymphocytes did not increase (2.0%-10.0%), as compared with 3.4%-9.5% in the group without complications.

The increased percentage of activated lymphocytes in the peripheral blood stream of patients with an acute graft versus host reaction (GVHD) after bone marrow transplantation results from specific immunological procedures. Their assessment could help with the differential diagnostic difficulties frequently associated with the diagnosis of the acute graft versus host reaction.