Autoimmune lymphoproliferative syndrome
Autoimmune lymphoproliferative syndrome, which is also known as ALPS, is a rare genetic disorder which causes the body's immune cells to turn against it. This disease usually affects the spleen and the lymph nodes, causing both to swell.
Definition & Facts
Autoimmune lymphoproliferative syndrome is a condition in which the body cannot control the number of immune system cells, known as lymphocytes, that are produced. Normally, lymphocytes die when they finish their task. With ALPS, the lymphocytes remain in the spleen and the lymph nodes, which causes the lymph nodes to swell (lymphadenopathy) and the lymphocytes to attack the body's tissues.
People with this condition are more likely to develop lymphoma or other types of cancer. Approximately 20 percent of people with this condition develop lymphoma. There are approximately 200 reported cases of ALPS.
Symptoms & Complaints
They may suffer from fatigue, weight loss, or pain in the muscles and joints. They may have shortness of breath. They may have hardened skin with lumps that are sensitive to the touch. The patient may develop arthritis, mouth sores, or an inflammation of the blood vessels.
This disease often manifests in young children. Children will experience enlarged lymph nodes and an enlarged spleen (splenomegaly). Some children develop the disease shortly after they are born.
Women may suffer premature ovarian failure or a loss of ovarian function. Many patients suffer frequent nosebleeds. Some may experience headaches, seizures, or dementia. Patients may develop a variety of conditions including autoimmune hemolytic anemia, immune thrombocytopenic purpura, autoimmune neutropenia, nephritis, hepatitis, autoimmune cerebellar ataxia, colitis, and pulmonary fibrosis. Virtually any organ can be affected by this disease.
Autoimmune lymphoproliferative syndrome is caused in most cases by a mutation in a gene called FAS. The FAS gene is responsible for producing proteins that tell specific cells to die once their task is complete. Mutations of this gene cause an abnormal protein which prevents cell death, particularly when the body is fighting an infection.
FAS gene mutations are responsible for around 75 percent of cases. ALPS is inherited most often in an autosomal dominant pattern. In some cases, the disease develops via de novo mutations in people without a family history of the condition.
Diagnosis & Tests
The physician will start off by inquiring about the patient's medical history and family history, as ALPS is frequently passed down from parent to child. The doctor will likely want to do a biopsy, checking the bone marrow or lymph nodes. They will be looking to rule out infections and other disorders. The doctor will perform a physical examination. They will look for an enlarged spleen and lymph nodes.
A blood test will be done to check the levels of red blood cells and white blood cells. They will test for anemia, elevated levels of vitamin B12, and elevated levels of lymphocytes. People with this condition tend to have low levels of cholesterol.
There may be genetic testing to look for the mutations in the FAS gene. Diagnosing children is very difficult because the symptoms overlap with a number of other disorders such as Evans syndrome and hereditary spherocytosis.
Treatment & Therapy
Patients will need to avoid strenuous activity to make sure their spleen doesn't rupture. The doctor may recommend that the patient wear a spleen guard, which is worn under the shirt to protect the spleen. Patients with a low amount of red blood cells may get blood transfusions.
Steroids like prednisone suppress the immune system, which can make them effective in treating some cases of ALPS. Steroids have many side effects, however. The doctor may administer prednisolone, sirolimus, methotrexate or a combination of these immunosuppressive drugs. Some patients will require ongoing immunosuppressive drugs in order to help prevent the body from rejecting a transplanted organ.
Children may need to have their spleen removed. This procedure is known as a splenectomy. Some people with severe cases may have a stem cell transplant. The patient may also opt for genetic counseling.
The biggest risks to watch out for are hypersplenism, sepsis, and lymphoma. If a patient can avoid these complications, they have a much better chance of recovery. The doctor will be watching closely for signs of lymphoma. In every case, the patient will need to have follow-up visits to the doctor over the long term.
Prevention & Prophylaxis
In order to reduce the risk of infection, people with ALPS are recommended to get childhood vaccinations. These include vaccinations against tetanus, measles, and hepatitis B. They should also get a flu shot each year.