дети, злокачественные заболевания, ложноотрицательный диагноз, инфекции, children, malignant diseases, false-negative diagnosis, infections, Medicine

The incidence of leukemia in children in various regions of the Russian Federation ranges from 1.9 to 4.1 per 100 000 of children aged 0 to 14 years. If the average annual morbidity of children is below the Russian (3.03) or European (4.0) standard, it is possible that some cases of leukemia and other oncological and oncohematological diseases are not reported. Clinical-laboratory and instrumental manifestations of malignant diseases can be similar to other conditions. It should be borne in mind that the most frequent childhood diseases are infections. Fever combined with bone pain, unexplained hepato- and/or splenomegaly, lymphadenopathy, changes in the cellular composition of blood and increased LDH should be the reasons to exclude malignancy.