Anemia is a frequent complication of nonspecific intestinal inflammations (NSZ). It occurs in 30-70% of patients, significantly influences their performance, cognitive functions and may result in substantial decreased of the quality of life of the patient. About one third of the patients with NSZ suffer from severe type of anemia, which is associated with extensive inflammatory affection of intestine and bleeding into intestine. Most significant etiopathogenetic factors are iron deficit and chronic inflammation. Discovery of the anemia cause in patients with NSZ is often difficult, but it is necessary for possible risks of supplementation iron therapy in patients with chronic intestinal inflammation. sTfR (soluble transferrin receptor) and TfR/F index (sTfR/log ferritin) is a sensitive and specific noninvasive laboratory test for the determination of iron deficit and activity of erythropoiesis suitable for the diagnostics also in patients with chronic inflammation in children and adolescents.

        Key words: anemia, iron deficit, anemia in chronic diseases, nonspecific intestinal inflammations, soluble transferring receptor