PHAGOCYTIC ACTIVITY OF NEUTROPHILIC GRANULOCYTES OF ORAL FLUID IN CHILDREN WITH ACUTE FORMS OF LEUKEMIA
Authors: Legenchuk O.V. , Nemyrovych Y.P. 
Published: May 2022

Relevance. In acute leukemia, the phagocytic activity of leukocytes changes. But the extend and details of these changes are still insufficiently studied.

Objective: to assess the state of phagocytic activity of phagocytic cells (neutrophils and macrophages) in terms of phagocytic index, phagocytic number and oxygen-dependent phagocytosis in children with acute forms of leukemia.

Materials and methods. We examined 35 children aged 6 to 16 years, who were at different stages of treatment of the underlying disease. The children were divided into two groups depending on the form of leukemia: Group I – nineteen children with acute lymphoblastic leukemia (ALL), nine of them at the stage of the first acute period, four at the stage of clinical remission, six at the stage of relapse; Group II - sixteen children with acute myeloid leukemia (AML), seven of them - at the stage of the first acute period, four -in the period of the clinical remission, five - at the stage of relapse. Control Group – fifteen practically healthy children. In oral fluid, the phagocytic activity of granulocytes was determined: phagocytic number (PN) – the percentage of phagocytic neutrophils; phagocytic index (PI) – the number (in conditional units) of phagocytosed microorganisms by one neutrophil; oxygen-dependent phagocytosis according to the NBT test (Nitroblue Tetrazolium) – the percentage of the maximum activity of neutrophils.

Results. PN in the control group - 70.0±5.1%. In children with acute lymphoblastic leukemia at the stage of the first acute period of PN - 85.7±5.8%, at the stage of remission - 73.8 ±6.1%, during the relapse period - 88.3% ±4.8. In children with acute myeloblastic leukemia at the stage of treatment of the first acute period, PN was 87.2±6.0%, at the stage of remission - 72.6±5.9%, at the stage of relapse - 89.1±5.1%.

PI in the control group – 3.9±0.6 In children with acute myeloid leukemia at the stage of treatment of the first acute period, PI was 21.1±0.7, at the stage of relapse – 25.3±0.4 In children with acute myeloblastic leukemia at the stage of treatment of the first acute period, PI was 16.1±0.5, during remission – 10.1±0.4, during the relapse period – 18.5±0.2.

The indicator of oxygen-dependent cell activity, according to the NBT test, in practically healthy children was 17.6±1.23%. In children with acute myeloblastic leukemia at the stage of treatment of the first acute period, the percentage of cell activity was 40.4±1.86%, at the stage of relapse - 46.4±2.0%, during remission - 23.7±1.56%. In children with acute myeloblastic leukemia at the stage of treatment of the first acute period, the percentage of cell activity was 41.6±1.34%, during the period of relapse - 48.5±1.05%, at the stage of remission - 27.9±1.86%.

Conclusion. The dependence of phagocytic activity of neutrophils in the oral fluid on the stage of treatment of acute leukemia in children was revealed. The phagocytic number, phagocytic index and oxygen-dependent phagocytosis are significantly increased at the stage of treatment of the first acute period and at the stage of relapse. At the stage of remission, the phagocytic number was within the normal range, but the phagocytic index and oxygen-dependent phagocytosis did not return to normal.

No difference was found between the phagocytic activity of neutrophils in various forms of acute leukemia – acute lymphoblastic leukemia and acute myeloblastic leukemia.