Chronic neutropenia is a prolonged condition in which the human blood has an abnormally diminished supply of immune cells that attack and destroy foreign material or organisms. At any given time, there is normal fluctuation in anyone’s blood count. A persistent, or cyclic, count that is unusually low may have a more serious underlying cause.
Hematology is the study of human blood, its composition and function. There are several types of white blood cells, collectively termed leukocytes. As blood circulates and permeates the entire body, white blood cells are the foot soldiers of the immune system, protecting against invasive foreign agents such as viruses that can harm or cause disease. Any hematological disorder that affects white blood cells compromises the human immune system.
The most common leukocytes in blood, anywhere from 50-60%, are the ones that primarily combat bacteria. They are called neutrophils. When bacteria invades the body, such as through any of the orifices or through a skin break, an army of neutrophils amass within 30 minutes to voraciously engulf and digest anything foreign at the site. They, too, die in the process, becoming a white substance commonly called pus.
During such bacterial infections, as neutrophils fight and die, their supply in the blood naturally diminishes. If the infection is severe, the supply can become substantially depleted. This condition is called acute neutropenia, sometimes also called leukopenia. Symptoms typically include inflammation or swelling of the infection site, absence of pus material, and high fever. Normal treatment is a course of antibiotic medication.
Chronic neutropenia is roughly defined as a persistence of the condition for three months. If not already tried, stronger antibiotics will be prescribed and a laboratory blood count will be conducted. A measurement of less than 500 neutrophil cells per microliter of blood is defined as severe chronic neutropenia. If obvious signs or symptoms of infection are absent, the diagnosis will include identifying the underlying cause of this blood disorder.
The various possible causes of chronic neutropenia is broadly either one of two: neutrophils are being destroyed, or they are not being produced. An example of the former includes autoimmune diseases such as lupus, in which the body mistakenly thinks that neutrophils are foreign organisms and thus produces antibodies that kill them on contact. Only a bone marrow biopsy, extracting some tissue for laboratory analysis, can determine whether this is the cause. Examples of the failure to produce neutrophils include cancers and hereditary diseases, chemotherapy and arsenic poisoning, and vitamin B12 and copper deficiency.
There are no known effective therapies for chronic neutropenia, because it is usually a symptom of an underlying disorder. Treat that disorder, and the white blood cell count will rise to normal. The focus of therapy is to prevent and treat any new bacterial infections which would exacerbate the condition.