In medicine, the word cyto refers to a cell, and penia means low or decreased. A cytopenia therefore, is a disorder characterized by low or decreased levels of one or more blood components in the circulation. Blood has several components including the red blood cells (RBC), platelets, and white blood cells (WBC). RBCs are cells that deliver oxygen and nutrients to all parts of the body. Platelets are important in blood clotting, and WBCs act to defend the body against infections.
The complete blood count (CBC) is a blood test often requested by physicians to evaluate the presence of cytopenia in ill patients. The CBC shows the value of WBC, platelets, and RBC in a blood sample. When all components of the blood are decreased, the condition is called pancytopenia. Pancytopenia is usually seen in cases of human immunodeficiency virus (HIV) infection, severe Vitamin B12 deficiency, and aplastic anemia, which is a condition where the bone marrow fails to produce blood cells.
A cytopenia that shows a deficiency in the amount of RBC in the circulation is known as anemia. Anemia is usually caused by other underlying diseases that result in bleeding, increased destruction of RBC in the circulation, and abnormal production of RBC by the bone marrow. Symptoms include poor concentration, weakness, palpitations or increased heart rate, and shortness of breath during exertion. If severe, anemia is usually treated with blood transfusion.
Low WBC in the circulation is called leukopenia. This type of cytopenia is frequently caused by infections such as malaria, influenza, and tuberculosis. Some forms of cancer, such as leukemia and Hodgkin's lymphoma also present with low WBC count. The most common cause of this form of cytopenia, however, is due to cancer treatments such as chemotherapy and radiation therapy. Patients with leukopenia may present with headache, weakness, and fever, and they are more prone to catch infections easily.
Low or reduced platelet count is known as thrombocytopenia. Thrombocytopenia is usually caused by other underlying conditions, such as bone marrow cancer and chronic liver disease, which lead to the decreased production of platelets. It may also result from the increased destruction of platelets in the circulation, such as seen in cases of dengue hemorrhagic fever (DHF) and chemotherapy treatment.
DHF is a viral infection transmitted by an infected mosquito. It usually presents with symptoms of sudden onset of high fever, severe headache, muscle pains, and rashes. The presence of bruises in the skin and bleeding from the nose and gums are also commonly seen among dengue patients and other patients with thrombocytopenia.