Table of contents
RBC Test
The number of red blood cells called erythrocytes in the complete blood count is one of the important tests. In a whole blood test, they are often abbreviated as RBC. Erythrocytes contain a substance in the blood called hemoglobin, which carries the oxygen needed by the body to organs and tissues.
In the neonatal period, the number of erythrocytes in the blood is physiologically high. The average lifespan of erythrocytes is 120 days in a normal person. While this period is between 50-70 days in newborns, it may be 35-50 days in premature babies.
Women generally have a lower RBC count than men, and the level of red blood cells tends to decrease with age.
In a normal blood count, the erythrocyte counts in the blood are usually as follows:
- Men – 4.0-5.9 x 10*12/L
- Women – 3.8-5.2 x 10*12/L
Normal ranges are indicative and may vary between different hospital laboratories.
Erythrocytes are examined in detail in the blood count. While looking at the total number of erythrocytes, other features are also examined separately. These:
- MCV: Mean erythrocyte volume
- RTC: Reticulocyte
- MCH: Mean erythrocyte hemoglobin
- MCHC: Mean erythrocyte hemoglobin concentration
- RDW: Erythrocyte distribution width
Evaluation of eristocytes can be done in many ways. The number and shape can be examined by performing a complete blood count (hemogram). In some cases, it may be necessary to examine the abnormal shapes of the erythrocytes, for which the peripheral blood smear is examined under a microscope. The tests may vary depending on the condition being investigated in the patient. The size of the erythrocytes may be reduced or enlarged. Growths outside the normal limits are also very important as they will have negative consequences for the patient. The dependent properties of erythrocytes in the hemogram are therefore very important. The shape or function of erythrocytes may be impaired.
An increase in the number of erythrocytes for any reason is called erythrocytosis. When erythrocytosis occurs, the total cell rate (hematocrit) in the blood also increases. Erythrocytosis occurs as congenital or acquired. They can also be divided into two groups as those due to primary or secondary causes.
The most common causes of erythrocytosis are:
- Primary erythrocytosis (autonomic)
- Hereditary and Congenital
- erythropoietin (EPO) receptor mutations
- Acquired
- Polycythemia vera
- Secondary erythrocytosis
- Hereditary and Congenital
- Hemoglobinopathies (high oxygen affinity hemoglobin)
- Congenital erythrocyte 2,3-bi-phosphoglycerate (2,3-BPG) deficiency
- Methemoglobinemias
- Mechanism of dysregulated oxygen sensitivity
- Chuvash polycythemia (vhl gene mutation)
- Pyrrolyl hydroxylase gene mutation
- Acquired
- Increased physiological erythropoiesis (low tissue oxygenation)
- high altitude
- Chronic lung diseases
- Alveolar hypoventilation
- Neurological central respiratory dysfunction
- Sleep-apnea syndrome
- Cardiovascular right-to-left shunts
- Carboxyhemoglobinemia
- Non-physiological (normal tissue oxygenation)
- Tumors
- Hypernephroma
- Wilms’ tumor
- Renal adenoma
- Adrenal tumors
- Meningioma
- Hepatocellular carcinoma
- Cerebellar hemangioblastoma
- Uterine fibromyoma
- Liver hamartoma
- kidney diseases
- Cysts
- Bartter’s syndrome
- Post-renal transplantation
- Hydronephrosis
- Renal artery stenosis
- Adrenal cortical hyperfunction
- Androgen therapy
- Tumors
- Idiopathic erythrocytosis
- Relative erythrocytosis “Stress erythrocytosis” (Gaisböck’s syndrome)
- Increased physiological erythropoiesis (low tissue oxygenation)
- Hereditary and Congenital
- Hereditary and Congenital
All causes of increased erythrocyte count should be evaluated separately, as they may have other accompanying symptoms and signs. You can review detailed information about these reasons in our articles under their own headings.