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BDS, MDS - Oral and Maxillofacial Pathology

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Dr. Ashish Ranjan

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Peripheral Smear Examination

Also known as Peripheral Blood Film Examination

You need to provide

Blood

This test is for

Male, Female

Test Preparation

No special preparation required
Provide brief clinical history/ doctor's prescription at the time of sample collection

Understanding Peripheral Smear Examination

What is Peripheral Smear Examination?

Peripheral Smear Examination test evaluates the different components of the blood. The smear evaluates the red blood cells, white blood cells, and platelets as well as other abnormalities such as the presence of parasites. The blood smear test is ordered to diagnose the cause of unexplained jaundice, unexplained anemia, unknown fever, and severe infection.

The number and the appearance of blood cells can be affected by a variety of diseases such as the smaller size of RBCs may indicate a type of anemia whereas increased number of WBCs may indicate infection.

A blood smear test is said to be normal when the sample contains an optimum number, size and shape of blood cells. The results are considered abnormal when cells have an abnormality in shape, size, and number.

What is Peripheral Smear Examination used for?

The peripheral smear examination is done:

In case of signs or symptoms of anemia such as weakness, fatigue, pale complexion, unexplained jaundice, and enlargement of the spleen.
In case the results of complete blood count or WBC differential is abnormal.
In case of signs or symptoms of conditions affecting red blood cell production.

Interpreting Peripheral Smear Examination results

Interpretations

The abnormal results depend upon the type of blood cell affected.

The abnormal red blood cells can be seen in conditions like:

Iron deficiency anemia
Sickle cell anemia
Hemolytic uremic syndrome
Polycythemia rubra vera

The abnormal white blood cells can be seen in conditions like:

Acute or chronic leukemia
Lymphoma
Hepatitis C virus infection
HIV
Viral infections like Dengue
Fungal infections such as candidiasis
Parasitic infections such as pinworm
Other lymphoproliferative diseases

The abnormal platelets can be seen in conditions like:

Thrombocytopenia
Myeloproliferative disorders

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Peripheral Smear Examination

Frequently Asked Questions about Peripheral Smear Examination

Q. What are the signs and symptoms of a blood disorder?

The signs and symptoms of a blood disorder include weakness, fatigue, pale complexion, fever, unexplained jaundice, episodes of bleeding, easy bruising, frequent nose bleeds, spleen enlargement, and bone pain.

Q. What conditions can affect the red blood cells?

The conditions which can affect the red blood cells include different types of anemia, myeloproliferative or myelodysplastic neoplasms, and bone marrow disorders.

Q. How is the blood sample taken?

The healthcare provider takes a blood sample from the arm. The site from where the blood is to be withdrawn is cleaned with a swab of rubbing alcohol. This is then followed by inserting a small needle which has a tube attached to it for collecting blood. Once the sufficient blood for analysis is withdrawn, the needle is removed. The site is then covered with a gauze pad.

Q. Is there any risk associated with the withdrawal of blood sample procedure?

As such there is no risk but in few cases, bruising, bleeding, and infection at the puncture site can be seen. In very few cases, there can be swelling of the vein after the blood is withdrawn.

Q. What type of RBCs irregularities can be seen on a smear in case of a condition affecting the RBC?

The most common RBC irregularity includes anisocytosis in which variable size of red blood cells is seen such as in case of anemia. If the size of the RBC is smaller than normal, it is called as microcyte while if it is larger than normal, it is called as macrocyte. If there is a variation in the shape of the RBCs, it is known as poikilocytosis. Examples include burr cells, rouleaux, sickle cells, elliptocytes, target cells, teardrop cells, and schistocytes. If there is variability in the size as well as shape of RBC, it is known as anisopoikilocytosis.

Q. What conditions can affect the absolute or relative number of WBCs and their appearance?

The conditions which can affect the absolute or relative number of WBCs and their appearance include infections and/or inflammation, bone marrow disorders, allergies, leukemia, myelodysplastic syndrome, or myeloproliferative neoplasm.

Q. In what conditions abnormal size of platelets can be seen?

The abnormal size of platelets can be seen in conditions like myeloproliferative neoplasms, immune thrombocytopenia, and in case the immune system inappropriately produces antibodies directed against platelets.

Q. What additional tests are advised in case of abnormal results are seen on the blood smear?

The additional tests include iron tests, folate tests, and flow cytometry immunophenotyping. The other tests could be bone marrow aspiration and bone marrow biopsy, BCR-ABL1, and hemoglobinopathy evaluation.

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