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The causes of increase and decrease of reticulocytes
Last reviewed: 29.11.2021
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The reference values (norm) of the reticulocyte content are 0.2-1% of all red blood cells circulating in the blood; with blood circulate 30-70 × 10 9 / l reticulocytes.
The number of reticulocytes in the blood reflects the regenerative properties of the bone marrow. An increase in the content of reticulocytes is observed with enhanced regeneration of hematopoiesis, a decrease in the inhibition of the regenerative function of the red bone marrow.
Increase in the number of reticulocytes is possible after blood loss, with hemolytic anemia, especially in times of crisis (up to 20-30% or more), as well as during treatment cyanocobalamine vitamin B 12 -scarce anemia (retikulotsitarny crisis - the increase in the number of reticulocytes in the 5-9 th day of treatment). Reticulocyte crisis is also noted on the 3-5th day of iron deficiency anemia treatment with parenteral iron preparations.
Modern hematological analyzers are able to detect 10 fractions of reticulocytes in the blood. Fraction of immature reticulocytes is the ratio of fractions from 3rd to 10th to the total number of reticulocytes and is in the norm 0.155-0.338 (using analyzers of Beckman Culter). When treating anemia with erythropoietin, the effectiveness of therapy is indicated by an increase in the fraction of immature reticulocytes, which can be detected on the 7th day from the start of treatment.
Diseases and conditions accompanied by changes in the number of reticulocytes
Increased number of reticulocytes |
Reduction of the number of reticulocytes |
Hemolytic Syndromes Acute lack of oxygen On the 3-5th day after hemorrhage (reticulocyte crisis) Vitamin B 12- deficient anemia on the 5-9th day after the start of treatment (reticulocyte crisis) On the 3-5th day of treatment with iron preparations of iron deficiency anemia |
Untreated vitamin B 12- deficiency anemia Metastases of bone tumors |