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Causes of increased and decreased red blood cells
Medical expert of the article
Last reviewed: 04.07.2025
Diseases and conditions accompanied by an increase in the number of red blood cells in the blood
Main pathogenetic groups |
Clinical forms |
Absolute erythrocytosis (increased production of red blood cells) Primary Secondary (symptomatic):
Relative erythrocytosis Mixed erythrocytosis due to blood thickening and placental transfusion |
Erythremia Lung disease, heart defects, presence of abnormal hemoglobin, increased physical activity, stay at high altitudes, obesity Renal parenchymal cancer, hydronephrosis and polycystic kidney disease, liver parenchymal cancer, benign familial erythrocytosis Cushing's syndrome. Pheochromocytoma, hyperaldosteronism Dehydration, emotional stress, alcoholism, smoking Physiological erythrocytosis of newborns |