Red blood cells develop in the bone marrow and, in a typical healthy human, survive in the circulatory system for 100 to 120 days. The premature breakdown of red blood cells, an event that can occur due to a wide range of disorders and conditions, is known as hemolysis. When the bone marrow of an individual is unable to produce enough red blood cells to offset those that are precipitately lost, hemolytic anemia ensues.

In instances of mild hemolytic anemia, the patient may be asymptomatic, but in severe cases, one’s life can become endangered. The elderly and people with cardiovascular problems are at greatest risk of death from hemolytic anemia, but overall the mortality rate associated with the disease is quite low. Some of the most common symptoms of hemolytic anemia include weakness, fatigue, darkened urine, pallor, jaundice, shortness of breath, fever, confusion, and rapid heart rate.

Though the readily observable symptoms of hemolytic anemia are similar to those of other types of anemias, there are several signs that can aid in a more specific diagnosis. Some key signs of the hemolytic form of the condition are only recognizable with the aid of a microscope. For instance, when blood smear examination reveals red blood cell fragments, an unusually large number of reticulocytes (immature erythrocytes), or atypically small, round cells, hemolysis should be suspected. Other indicators that an individual’s anemia is hemolytic include elevated levels of lactate dehydrogenase and unbound bilirubin in the blood as well as a decrease in the protein haptoglobin.

The etiology of hemolytic anemia is diverse, the condition arising from a host of intrinsic and extrinsic factors. The most common intrinsic cause of hemolytic anemia is hereditary spherocytosis, which is characterized by small, mostly spherical cells that are unusually fragile and are stored in the spleen for extended amounts of time due to their abnormal shape. The removal of the spleen is a common treatment for individuals with pronounced anemia caused by spherocytosis, but it does not hinder the trait from being passed on to future generations. Common extrinsic causes of hemolytic anemia include a number of toxins, such as naphthalene, and oxidant drugs, such as various antimalarial agents.

Hemolytic Anemia at 20x Magnification - Autoimmune hemolytic anemia can occur spontaneously, or in the presence of other ailments, and involves the body's production of antibodies against its own red blood cells.