Peripheral blood smear

A peripheral blood smear test is used to help diagnose blood disorders.

A blood smear is a sample of blood that’s tested on a specially treated slide. For a blood smear test, a laboratory professional examines the slide under a microscope and looks at the size, shape, and number of different types of blood cells. These include:

  • Red blood cells, which carry oxygen from your lungs to the rest of your body
  • White blood cells, which fight infection
  • Platelets, which help your blood to clot

Many blood tests use computers to analyze results. For a blood smear, the lab professional looks for blood cell problems that may not be seen on a computer analysis.

our results will show if your blood cells look normal or not normal. You’ll have separate results for red blood cells, white blood cells, and platelets.

If your red blood cell results are not normal, it may indicate:

  • Anemia
  • Sickle cell anemia
  • Hemolytic anemia, a type of anemia in which red blood cells are destroyed before they can be replaced, leaving the body without enough healthy red blood cells
  • Thalassemia
  • Bone marrow disorders

If your white blood cell results are not normal, it may indicate:

  • Infection
  • Allergies
  • Leukemia

If your platelet results are not normal, it may indicate thrombocytopenia, a condition in which your blood has a lower than normal number of platelets.

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.