Mechanism |
Examples |
Bone marrow does not produce enough platelets |
Heavy alcohol consumption Vitamin deficiency anemias, including vitamin B12 and folate deficiency anemias Some bone marrow disorders Some chemotherapy drugs |
Platelets become entrapped in an enlarged spleen |
Cirrhosis of the liver that causes spleen enlargement due to abnormally high blood pressure in the large vein that brings blood from the intestine to the liver |
Platelets become diluted |
Massive red blood cell replacement or exchange transfusion; stored red blood cells do not contain very many platelets |
Use or destruction of platelets increases |
HIV infection and other viral infections Drugs such as heparin, quinine, many antibiotics (such as trimethoprim/sulfamethoxazole, rifampin, and vancomycin), and some oral drugs for diabetes Conditions involving disseminated intravascular coagulation within blood vessels, as can occur with complications of childbirth, cancer, blood poisoning (septicemia) due to gram-negative bacteria, and traumatic brain damage |