Peripheral blood smear tests, in which a blood sample is taken and then observed under a microscope, can serve a variety of functions:
- To assess the levels of red and white blood cells.
- To diagnose any disease or disorder that affects blood cell production or growth.
- To monitor the effectiveness of treatment for diseases like leukemia.
Results of a blood smear test include several measurements. The first measurement is the red blood cell (RBC) count. The test results will note irregularities in size, shape, or color of the red blood cells. A significant portion of over-sized cells can indicate a vitamin deficiency; common vitamin deficiencies include B12 and folate, and may be indicative of anemia or alcoholism. Small or undersized red blood cells may indicate an iron deficiency or a more serious genetic disorder.
Red Blood Cells
Red blood cells should be round. There are several shape abnormalities that could occur with red blood cells: Crescent shaped cells are indicative of sickle cell anemia, whereas cells with a scalloped edge might indicate liver disease. Dark red blood cells might indicate dehydration; pale cells indicate low levels of hemoglobin in the blood. Immature blood cells appear blue on a blood smear test.
White Blood CellsThere are five types of white blood cells, and abnormalities in size or percentage of each type could indicate several problems:People will parasites will often present increased levels of eosinophils. Certain types of leukemia cause high numbers of basophils.Neutrophils should make up between 50 to 70 percent of the entire white blood cell countLymphocytes account for the other 20 to 40 percent of white blood cell totals. Monocytes, basophils, and eosinophils all represent between 1 and 6 percent of white blood cell counts.Blood smear tests also report levels of platelets, the part of the blood responsible for blood clotting. Low platelet counts indicate a deficiency in clotting ability and increased risk of blood loss death. A normal platelet count in a healthy adult is between 150,000 and 450,000 parts per micro liter. Leukemia, chronic bleeding ulcers, and lupus can also decrease the amount of healthy platelets in a blood smear test result.Blood smear tests are not typically the sole diagnostic tool used in identifying or treating diseases, however, the tests can alert a doctor to a problem. Any abnormalities on a blood smear test should lead to additional screening or testing procedures in order to determine the exact illness and treatment.
