Erythrocyte count (RBC count)

Your doctor may order an RBC count as a part of complete blood count for a routine health check-up or it may be recommended if you show symptoms of abnormal RBC levels such as:

• Paleness
• Weakness
• Fatigue
• Lack of energy
• Dizziness
• Headache
• Blurred vision
• Enlarged spleen

Regular monitoring of erythrocyte is advised for individuals who are diagnosed with one of the following conditions:

• Kidney disorder
• Chronic anaemia
• Cancer and those undergoing chemotherapy
• Polycythaemia
• Bone marrow disorder
• Bleeding problems

No special preparation is needed before an erythrocyte count. 

Tell your doctor if you have had a recent infection or disease or if you are taking any prescription or non-prescription medicines or supplements. Your doctor may need to modulate the course of a few medications; they will let you know about it. It is not advisable to change the course or dosage of any medication on your own. 

You may also be advised to avoid exercising heavily, drinking alcohol, getting dehydrated or being stressed before the test.

A blood sample is needed for the RBC count. At the testing facility, a nurse or a lab technician will collect a small amount of blood from a vein in your arm using a sterile needle. You might feel slight pain as the needle pierces your skin - it will diminish soon. After withdrawing the blood, the technician will transfer it to a particular container and send it for testing. 

A few people tend to develop a bruise at the site of needle insertion. However, it fades away on its own. Talk to your doctor if you notice an infection at the needle insertion site.

Normal results:

The results of the erythrocyte count test are given in terms of a range of values. The exact value of RBCs in the blood sample depends on the age, gender and lifestyle of the person. The normal range of the test result can also vary from one laboratory to another. Standard values for RBC are:

• Female: 4.2-5.4 million cells per microliter (cells/mcL)
• Male: 4.7-6.1 million cells/mcL

Abnormal results:

Any values which are outside the normal range prescribed by the laboratory are considered abnormal. Both high and low levels of RBCs in the blood can be an indicator of a certain disorder. The following is a list of conditions associated with higher-than-normal RBC count:

• Congenital heart disease (structural and functional problem with the heart since the time of birth)
• Smoking
• Dehydration
• Tumour in the kidney
• Right-sided heart failure
• Thickening or scarring of the lungs
• Hypoxia (low blood oxygen levels)
• Bone marrow disorder that leads to excess RBC production called polycythaemia vera
• Intake of certain drugs such as methyldopa and gentamicin

Being at a higher altitude for a few weeks can also lead to a rise in the RBC count.

A low RBC count is associated with the following conditions:

• Anaemia
• Malnutrition
• Bleeding
• Leukaemia
• Overhydration (too much water in the body)
• Erythropoietin deficiency (a hormone produced by the kidney that helps to regulate RBC levels)
• Bone marrow failure due to toxins, radiation and tumours
• Multiple myelomas (cancer of the bone marrow)
• Destruction of the RBC due to blood vessel injury or transfusion
• Deficiency of vitamin B12, vitamin B6, iron, folic acid or copper in the body
• Pregnancy
• Intake of specific medications such as chloramphenicol, chemotherapeutic drugs, quinidine and hydantoins

Please refer to your doctor for the correct interpretation of your results.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.