Anemia, iron-deficiency anemia, pernicious anemia, aplastic anemia and autoimmune hemolytic anemia are blood disorders that cause fatigue and weakness, according to WebMD. Sickle cell anemia is a genetic blood disorder that prevents sufficient oxygen delivery to the body’s tissues, resulting in tiredness and pain.
A low red blood cell count is the primary characteristic of anemia, and in severe cases, patients experience fatigue and shortness of breath upon exertion. The cells, tissues and organs do not get enough oxygen to function at optimal levels, states WebMD. Iron-deficiency anemia is caused by insufficient iron intake, blood loss during menstruation, or ulcers or cancer in the GI tract. When the body is unable to absorb enough vitamin B-12 due to an autoimmune condition or a weakened stomach lining, pernicious anemia can develop. Aplastic anemia occurs when bone marrow does not produce enough red blood cells due to a viral infection or an autoimmune condition.
The crescent-moon-shaped red blood cells found in sickle cell anemia get stuck in the blood vessels and block the flow of oxygen, explains WebMD. This lifelong, hereditary disease can harm organs, bones and muscles, causing pain, infections and stroke. Autoimmune hemolytic anemia occurs when the body’s immune system destroys red blood cells. There are over 400 different types of anemia, making it the most common blood condition in the United States.