Causes of Low RBC

Anemia is caused by having a low red blood cell count. Red blood cells, or RBCs, contain a protein called hemoglobin, which carries oxygen to the different tissues of the body. The amount of oxygen that is supplied to the different tissues depends on the amount of RBCs present in the body. In anemia, the body does not have enough hemoglobin in the red blood cells, which leads to a lack of oxygen supply to the tissues. According to Medline Plus, there can be a number of causes of low RBC.

There are certain medications that can decrease the red blood cells in the body, MedlinePlus states. These medications include drugs that are used in chemotherapy for treatment of cancers, quinidine, hydantoins and chloramphenicol.

There are some forms of anemia that are genetic and can be inherited, says MayoClinic.com. These include thalassemia, which is caused by a defective protein found in red blood cells. Diseases affecting the immune system that can cause the destruction of blood cells are another cause of low RBC. This condition is called hemolytic anemia, where the body is responsible for producing antibodies which destroy the red blood cells..

Blood loss may be a cause of anemia, according to MedlinePlus. An individual have excessive bleeding due to conditions such as stomach ulcers and cancer. Heavy menstrual periods in women may also lead to anemia.

Certain chronic diseases can lead to a low RBC count, according to MayoClinic.com. These include cancer, rheumatoid arthritis, HIV/AIDS, which can decrease the production of the healthy red blood cells and this can cause anemia. Most of the red blood cells are produced by the bone marrow, which is a soft tissue in the center of the bones. Certain conditions affecting the bone marrow can lead to a low RBC count. These conditions include leukemia, multiple myeloma, and lymphoma. The kidneys produce a hormone called erythropoietin which signals the bone marrow to produce more red blood cells. In individuals with kidney failure, the production of this hormone is affected. This can cause a low RBC in individuals.

MayoClinic.com reports that diets lacking iron and vitamins, can lead to a low red blood cell count. Poor diet and nutritional deficiencies may lead to a low red blood cell count. Pregnancy can often cause nutritional deficiencies in women, causing anemia. Surgeries of the stomach or intestines reduce the absorption of iron, vitamin B12, and folic acid. This can cause a decrease in the red blood cells.