An autosplenectomy is a rare but serious disorder that arises from the effects of other diseases. It occurs when the spleen shrinks and becomes nonfunctional.
Definition & Facts
An autosplenectomy is a form of asplenia or the loss of the spleen. Autosplenectomy only refers to cases where the spleen shrivels and ceases to function within the body as a result of a medical problem as opposed to the surgical removal of the spleen (splenectomy).
The process is usually gradual and occurs as a result of other diseases or lifestyle factors. Damage to the spleen is usually impossible to repair, although some of the symptoms that result from the damaged spleen can be treated. An autosplenectomy can result from an autoimmune disease.
The defining characteristic of autosplenectomy is the loss of normal spleen function. A healthy spleen has several important functions that can prevent disease, including filtering red blood cells to remove toxins, triggering the destruction of unhealthy cells in a process known as phagocytosis, and allowing white blood cells to contribute to the body's defenses. All of these processes are inhibited when the spleen is lost, and although other organs can compensate to some extent, patients do suffer a variety of symptoms from it.
Symptoms & Complaints
Autosplenectomies are extraordinarily rare, and they are also strongly correlated with certain diseases. The most common cause is sickle-cell disease, which is characterized by rigid and misshapen red blood cells. Sickle-cell disease is a genetic disorder, so most of the risk of developing an autosplenectomy is genetic.
In rare cases, these abnormal blood cells will clog the patient's veins near the spleen. This causes unhealthy blood to accumulate inside the spleen without properly flowing through the system; this causes the organ to cease normal function and to atrophy. Infections that attack the spleen can also cause the disease, although scientists do not fully understand why that process occurs.
The disease has been linked to whole-body exposure to a species of bacteria, Streptococcus pneumoniae, although the infection only progresses to a full autosplenectomy in a very small minority of cases.
Finally, several other autoimmune disorders, most notably systemic lupus erythematosus, have also been linked to autosplenectomies. These cases lead to infarction (or the reduced blood supply) to the spleen, causing cell death and permanent damage.
Diagnosis & Tests
Autosplenectomies are very strongly linked to a small number of diseases, so most doctors will keep an eye on the spleen of any patient who suffers from those diseases. This means that autosplenectomies are usually diagnosed fairly quickly once the problem begins to manifest.
The primary method of diagnosis is blood testing. This not only reveals if the patient suffers from certain underlying diseases like sickle-cell disease or lupus but it also provides valuable information about how far the problem has progressed.
Red blood cells tend to accumulate waste material over time which can manifest as pits, and one of the spleen's functions in a healthy body is the removal of this waste from the cells. The average healthy person will have pits on less than two percent of their cells, while patients that suffer from an autosplenectomy will have pits on as many as half of their red blood cells.
Cells will also accumulate Howell-Jolly bodies over time, which are clumps of DNA. The spleen removes them in healthy patients, so their presence is evidence of the disease. A blood test will reveal both of those problems, which are taken as reasonably conclusive proof that the patient's spleen is not functioning properly.
Imaging studies like computed tomography (CT) scans and magnetic resonance imaging (MRI) scans can be used to detect the presence or absence of the spleen as well as symptoms such as ascites, pleural effusion, and abnormalities of the liver.
Treatment & Therapy
It is usually impossible for doctors to reverse autosplenectomy. Once normal spleen function is gone, it is irreversible. However, physicians have developed methods for treating most of the disease's most dangerous symptoms, particularly the patient's vulnerability to infections.
Vaccinations form the core of the method, since they can strengthen the immune system to the point where it can resist some diseases even without the spleen's help. In the event that the patient develops an infection, doctors will almost always provide antibiotics, even in cases where they would not be necessary for healthy patients.
Antibiotics are also given in advance of most surgical procedures and any other planned events that carry a risk of infection. The autosplenectomy will still reduce a patient's expected lifespan after these methods are applied, but they can significantly reduce the problems associated with the disease.
Prevention & Prophylaxis
It is somewhat easier to prevent the symptoms from developing. Patients can reduce their risk of exposure to infectious agents by avoiding areas in which infections are common, and by taking pains to avoid animals bites and exposure to insects. Many patients also carry a medical alert bracelet.