What does peripheral blood chromosome examination mean

Peripheral blood chromosome examination is a laboratory testing method that analyzes the number and structure of chromosomes by collecting venous blood.

Peripheral blood chromosome examination is mainly used to diagnose chromosomal abnormalities related diseases. The detection process requires the extraction of 2-5 milliliters of venous blood. After cell culture, chromosome preparation, and other steps, the morphology, quantity, and structure of chromosomes are observed under a microscope. This examination can detect chromosomal abnormalities such as trisomy 21 syndrome and structural abnormalities such as translocations, deletions, and other types of mutations. The specimen collection for chromosome examination is usually completed in outpatient settings and does not require fasting. Lymphocytes in peripheral blood can enter the division phase under specific culture conditions, making it easier to observe chromosome status. Laboratory technicians will analyze at least 20 split phases to ensure the accuracy of the results. The examination report generally includes a description of the chromosome karyotype, such as a normal female karyotype of 46XX and a normal male karyotype of 46XY.

Common indications include screening for recurrent miscarriage causes, screening for congenital malformations, and assessment of intellectual disability. Prenatal diagnosis requires the use of other testing methods such as amniocentesis or chorionic villus sampling, as peripheral blood tests only reflect an individual's current chromosomal status and cannot detect fetal conditions. Before the SEP examination, medical procedures such as recent blood transfusions or bone marrow transplants that may affect the results should be avoided. Pregnant couples, those with a family history of genetic diseases, and elderly pregnant women may consider undergoing this examination. It is recommended to comprehensively evaluate the necessity of the test under the guidance of a specialist and seek genetic counseling based on the results.