Asplenia: Causes, Symptoms & Treatment

In asplenia, the spleen is dysfunctional or absent. This condition may be congenital or acquired. The spleen is an important organ in the human immune system because it is responsible for filtering certain pathogens in the blood. Normally, the body’s immune system can compensate well for the absence of the spleen‘s function. However, asplenia patients have a higher risk of developing life-threatening sepsis due to bacterial, fungal or parasitic infection. Therefore, for this type of infection, these individuals should be treated as soon as possible.

What is asplenia?

Asplenia is an inability of the spleen to function. The organ is also called the lien or splenium and is located in the left upper abdomen. The spleen consists of connective tissue which is constantly perfused with blood. The cells in this tissue absorb pathogens and old blood cells and destroy them. This function is also called blood moulting. Accordingly, the organ has the task of filtering the blood in the human body. In anatmotic asplenia, this organ is not present. This is to be distinguished from so-called functional asplenia, in which the organ is present but not functional. The clinical picture of hyposplenia is to be separated from this. In this case, the organ is present but its function is weakened. A splenectomy is a surgical removal of the spleen. This may be necessary in certain diseases and circumstances such as tumors.

Causes

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Anatomic congenital asplenia occurs rather rarely. Frequently, the malposition of the organ is associated with congenital heart defects. This malposition of the organ is due to a midline defect. If a patient is affected by both congenital asplenia and a heart defect, he suffers from the Ivemark symptom complex. This clinical picture can be classified as heterotaxy. Heterotaxy in general describes a congenital rearrangement of human organs from the actually physiological side of the body to the other. The leading symptom of the Ivemark symptom complex refers to a displacement, malformation or absolute absence of the spleen. The exact cause of development of this disease is unknown to date. However, a genetic predisposition cannot be ruled out, as it may occur in clusters within a family. Comparable to an anatomical asplenia is the so-called autosplenectomy. This can occur as a result of multiple splenic infarctions. These can be caused by hemorrhage or fibrosis. Fibroses are pathological hardenings of tissues that can result in a functional disorder. Functional asplenia must be distinguished from anatomical asplenia. This can result from autoimmune disease, stem cell transplantation, sickle cell anemia, or amyloidosis. Sickle cell anemia is a hereditary disease that is manifested by a reduction in the lifespan of red blood cells. Amyloidosis is a pathologically altered deposition of proteins in the intercellular space. Particularly in sickle cell anemia, dysfunction of the spleen usually occurs after the first year of life. Untreated patients develop anatomical asplenia from this over the next few years, triggered by splenic infarcts. Hyposplenia may develop in untreated HIV-positive individuals or after stem cell transplantation.

Symptoms, complaints, and signs

Asplenia patients are at higher risk for infections. Certain bacteria, such as pneumococcus, can result in severe blood poisoning. In addition, the risk of suffering a fungal infection is increased. American data from the 1980s further indicate that the risk of pneumonia and meningitis is higher for asplenia patients. Sufferers of asplenia suffer from decreased blood flow through the spleen and a lowered immune system response. Because of this, infections can pose dangerous risks for them. In addition to pneumococcus, asplenia patients are at particular risk of developing life-threatening sepsis from meningococcus and Haemophilus influenzae. Their immune systems cannot fight off these encapsulated bacteria as quickly as healthy people. It’s not just bacteria that can cause problems for asplenia patients. Parasites, tick, dog and cat bites, and malaria can take a worse course in these patients than in healthy people.

Diagnosis and course

The diagnosis of asplenia is made by a blood test. The decisive factor is the so-called Howell-Jolly corpuscles. These corpuscles normally contain nucleate red blood cells that are formed from DNA residues. Normally, these corpuscles are broken down by the spleen. In asplenia, they are detectable in the blood because they are not filtered from the blood due to the absence or dysfunction of the organ. Logically, patients with functional asplenia have lower Howell-Jolly levels than people with anatomic asplenia. The latter can also be detected by diagnostic imaging such as an ultrasound or computed tomography scan.

Complications

Several complications can occur because of asplenia. First, the inability of the spleen to function increases the risk of infections; specifically, pneumococcus and other capsule-bearing bacteria can cause severe health problems in asplenia. In less severe cases, the infections cause typical fever symptoms; in severe cases, life-threatening sepsis occurs. The risk of fungal infections also increases with asplenia. In addition, the inability of the spleen to function increases the risk of infections with Capnocytophaga canimorsus and other gram-negative pathogens, which are transmitted, for example, by animal bites and tick bites. In addition, asplenia reduces the production of IgM antibodies and memory B cells, which can lead to increased liver disease and infections of other organs. The impaired IgM antibody production also means that vaccinations have a much slower and less potent effect, increasing the risk of diseases such as tetanus. The mortality rate for asplenia is approximately 46 percent, due to the wide-ranging complications and many risks associated with a nonfunctioning spleen. Early treatment, as well as patient education, can greatly reduce the risk of serious complications.

Treatment and therapy

Normally, the body’s immune system can protect the organism from pathogens even when the spleen is dysfunctional or absent. However, it is recommended as the most important prophylaxis against severe complications to vaccinate asplenia patients to protect them from bacteria and possible life-threatening situations. In particular, vaccination against pneumococcus, meningococcus and Haemophilus influenzae are important. In some cases, permanent treatment with antibiotics is induced. It is important to fully educate the patient about their clinical picture during treatment. If certain warning signs occur in an asplenic patient, he or she should seek medical treatment immediately. To this end, it is important that patients are trained with regard to these signals. These include fever above 38 degrees Celsius, flu-like effects, confusion, rapid heartbeat, severe abdominal pain or dizziness.

Outlook and prognosis

The prognostic outlook for asplenia is highly individualized and depends on the patient’s health consciousness. Generally, the stronger the health consciousness, the better the prognosis. With a healthy lifestyle and regular participation in checkups, the affected person has the opportunity to live his or her life for the rest of his or her life without further impairments and without supplementary treatment measures. The lifespan is not shortened and complete freedom from symptoms is possible. The control examinations are necessary to detect possible pathogens in the organism at an early stage and to counteract them. The more unhealthy the patient’s lifestyle is and the less he/she makes an effort to have a medical check-up, the greater is the risk of being attacked by germs. These trigger diseases whose prospects of cure must be considered on an individual basis. Nevertheless, the immune system is weakened and can thus trigger immense problems even in the case of minor illnesses. The natural protection against the pathogens is not given in case of asplenia. As soon as the affected person neglects this, his own risk of disease increases. In severe cases, he succumbs to a disease that his own immune system cannot cope with despite all efforts. This can then result in death. This occurs in particular when participation in necessary vaccinations is not perceived and the pathogen is particularly aggressive.

Prevention

There are different causes for the clinical picture of asplenia.In addition, there are various diseases that make it necessary to remove the spleen. Accordingly, there is no certain prevention of this disease at the present state of knowledge.

Follow-up

Asplenia is not considered curable. Affected individuals therefore suffer from the inability of the spleen to function throughout their lives. The goal of follow-up cannot be to prevent recurrence of the disease. Rather, the aim is to support patients in their daily lives and to stop complications. Asplenia can be diagnosed by a blood test. In addition, doctors regularly order sonography and computed tomography for detection. A significant part of the aftercare must be provided by the patient, such as adequate hygiene measures to prevent infection. This includes, above all, avoiding crowds during the period when the patient has a cold. But careful hygiene after visiting public sanitary facilities is also important. If initial signs of asplenia develop, the affected person must consult a doctor immediately. This is the only way to prevent complications. Early antibiotic therapy leads to relief of the symptoms. Important preventive measures also include carrying an emergency card that lists the status of vaccinations. Malaria areas should also be avoided when traveling abroad. Regular check-ups can be arranged with a doctor if necessary. In addition to the conversation about the state of health, the blood test plays an important role.

What you can do yourself

Because the spleen is either absent or completely nonfunctional in asplenia, there are no methods that allow self-therapy of the underlying disease. However, patients can help manage the risks associated with asplenia. The spleen plays an important role in the immune system of the human body. in particular, the spleen is extremely important for defense against encapsulated bacteria, such as pneumococcus, and in defense against other parasites. People suffering from asplenia therefore have a greatly increased risk of developing severe sepsis after a simple infection. Consequently, prevention has an important role to play. Situations that favor infection with bacterial infectious diseases are dangerous for those affected. If possible, public transportation and other crowds should be avoided during the cold season. Shaking hands should be avoided, as this is a particularly effective way of transmitting pathogens. Regular hand washing can also reduce the risk of infection. At the first signs of an infectious disease, such as a slight fever or unprovoked exhaustion in conjunction with loss of appetite and chills, the doctor should be consulted immediately so that treatment with antibiotics can be initiated promptly if necessary. In addition, vaccination can significantly reduce the risk of postsplenectomy sepsis.