Platelets are disk-shaped, colorless cells in the blood that form plugs during blood coagulation. The condition of having low platelet numbers, called thrombocytopenia, has symptoms of easy bruising, excessive bleeding after being cut, heavy menstrual flow, and bleeding in the mouth after dental work. Thrombocytopenia is a dangerous condition because it can result in internal bleeding. Seek medical attention if you experience unusual symptoms of heavy bleeding or bruising.
Reduced Platelet Production
Like other components of the blood, platelets are produced in the bone marrow. The Mayo Clinic explains that diseases that affect the bone marrow can impact platelet production and may lead to low platelet numbers. Certain cancers, specifically leukemia, are often associated with thrombocytopenia through their impact on bone marrow. Viral infections, notably HIV infection can also decrease platelet amounts. A number of chemical and prescription drugs can also have bone marrow side effects that result in thrombocytopenia.
Platelet Trapping in the Spleen
The spleen is a small, fist sized organ located in the abdominal region. The spleen plays a critical role in the immune system by filtering out bacteria, viruses and other unwanted particles from the blood stream. The National Heart, Lung and Blood Institute describes how certain conditions such as liver disease can lead to an enlargement of the spleen, which can then trap platelets. As platelets accumulate in the spleen, the spleen enlarges further, trapping even more platelets away from the blood stream, leading to thrombocytopenia.
Platelet Degradation
Thrombocytopenia can also occur when the body breaks down platelets faster than they are produced. According to the Mayo Clinic, a number of conditions can lead to increased platelet breakdown. Pregnancy is one condition that can lead to platelet breakdown and thrombocytopenia. Certain autoimmune diseases can cause the immune system to attack platelets and cause thrombocytopenia. Idiopathic thrombocytopenic purpura (ITP) is a specific immune condition in which the immune system perceives platelets as a threat, leading to their degradation. Certain medications can also alter immune function, leading to platelet degradation and low platelet count.
