The aim of this investigation was to study the clinical effect of rh-G-CSF in non-Hodgkin's lymphoma paediatric patients with chemotherapeutic myelosuppression and to elucidate the ultrastructural peculiarities of the peripheral blood leukocytes, especially granulocytes in different time during treatment by Figrastim (Neupogen, Roche). The preparation was administrated s/c at 5 ug/day for 5 to 7 days. The study of blood cells, including electron microscopy (TEM 100 C, TEOL) was carried out before and during treatment of 12 children with NHL, 8-11 years old. Our experience demonstrated the clinical efficacy of high dose chemotherapy with supportive care therapy by rh-CSF; 2-3 days after administration of Filgrastim the absolute number of leukocytes was markedly increased. Absolute neutrophil count was 10,37±2,03 VS 0,45±0,19·109/L, p<0,001.

We noted that segmented and juvenile neutrophils have some ultrastructural changes: the nuclei present membrane contour alterations and the cytoplasm was characterised by increasing number of smaller electon-dense specific granules and enlarged in length mitochondria. Ultrastructural analysis of mononuclears has shown that peripheral blood lymphocyte-like cells are morphologically similar to early progenitor cells. Our data show in detail that evidence of ultrastructural peculiarity of mobilized blood cells exist and point out an enhancement of functional activity of neutrophils, during treatment of patients with Filgrastim.