Hemophagocytic lymphohistiocytosis is a disease that affects the immune system. The disease generally occurs with a very low frequency. Hemophagocytic lymphohistiocytosis is usually characterized by a severe course. In addition, it represents a so-called hyperinflammatory disease.
What is hemophagocytic lymphohistiocytosis?
Hemophagocytic lymphohistiocytosis is characterized by the main symptoms of fever, skin changes, and liver and spleen enlargement. Sometimes, the lymph nodes of affected patients also swell. Ascites or pleural effusions are also possible. Approximately 30 to 50 percent of all affected individuals die from the disease. Hemophagocytic lymphohistiocytosis is basically differentiated into a primary and a secondary manifestation. Primary hemophagocytic lymphohistiocytosis is also known as Farquhar’s disease. It occurs rarely and is fatal for affected individuals. In principle, this form is counted among the genetic diseases. In many cases, familial clustering of this disease is seen. However, sporadic occurrence is also possible. In the majority of cases, this disease begins in infancy. The secondary form of hemophagocytic lymphohistiocytosis, on the other hand, is associated with various infections. In this case, there is no genetic component. In addition, occurrence of the disease is possible at any age.
Causes
The causes of the disease differ depending on whether it is the primary or secondary form of hemophagocytic lymphohistiocytosis. The primary form has primarily genetic causes. In this case, mutations occur on certain genes, so that familial hemophagocytic lymphohistiocytosis develops. This in turn is divided into different subcategories. Basically, there are four different forms, which are characterized according to the localization of the genetic mutation. If secondary hemophagocytic lymphohistiocytosis is present, various infections are usually responsible. In particular, bacterial pathogens, viruses or parasites are potential triggers of the disease. In addition, the cells responsible for the formation of blood may degenerate. In some cases, certain autoimmune diseases such as systemic lupus or rheumatoid arthritis also lead to the development of hemophagocytic lymphohystiocytosis. This is because both macrophages and T cells are stimulated in the course of these diseases. The result of this activation is that increased messenger substances are produced. In this way, there is a strong stimulation of T helper cells. They produce large quantities of pro-inflammatory substances. These substances cause macrophages to multiply and spread in the liver, the marrow of the bone, and the lymph nodes.
Symptoms, complaints, and signs
Hemophagocytic lymphohistiocytosis is characterized primarily by fever that persists for a period of more than a week. The body temperature rises above 38.5 degrees Celsius. At the same time, the spleen of the affected person enlarges, which is also referred to as splenomegaly in medical terms. Other symptoms can be detected primarily by blood analysis methods. For example, certain cell counts in the blood are reduced, blood lipid levels are elevated, and the substance fibrinogen is decreased. Hemophagocytosis can also be detected. This is a special process in which macrophages digest blood cells. This process takes place in the spleen, the marrow of the bones or the lymph nodes. Other symptoms include enlargement of the lymph nodes, edema, and rashes on the skin and jaundice. In addition, there are often elevated levels of liver enzymes, an increased concentration of the substance ferritin, and increased proteins in the blood of affected patients. At the same time, the concentration of sodium is reduced. If the disease occurs in children, there are also symptoms that indicate an impairment of the central nervous system. Typical symptoms include stiffness of the neck, increased intracranial pressure and seizures. In addition, the amount of proteins in the cerebrospinal fluid may be increased.
Diagnosis and course of the disease
The first priority is for the specialist to take a medical history. The diagnosis of hemophagocytic lymphohistiocytosis is made on the basis of clinical symptoms and complaints. Blood analyses in particular provide important information on the presence of the disease. Based on typical changes in various parameters, hemophagocytic lymphohistiocytosis can be diagnosed with relative certainty.
Complications
Lymphohistiocytosis primarily results in a weakened immune system. The affected person falls ill more often and relatively severe fever occurs. Likewise, an enlargement of the spleen occurs, which is usually associated with pain. This enlargement may permanently displace or squeeze other organs. Furthermore, jaundice occurs and rashes appear on various parts of the skin. Patients also suffer from general fatigue and exhaustion and often exhibit seizures. The intracranial pressure is increased, which can lead to severe headaches. It is not uncommon for these pains to spread to the neck and back and may cause discomfort in these regions as well. In most cases, the diagnosis of lymphohistiocytosis is made relatively quickly, so that treatment can be initiated at an early stage. In this case, a stem cell transplant is necessary to alleviate the symptoms. Furthermore, other medications are also used, although there are usually no particular complications. However, the further course of the disease depends on the underlying disease. In this case, life expectancy may also be reduced.
When should you go to the doctor?
Hemophagocytic lymphohistiocytosis should be promptly evaluated by a physician. As soon as typical symptoms such as persistent fever or rashes on the skin are noticed, a visit to the family doctor or an internist is indicated. If further symptoms such as edema or signs of jaundice become apparent, a doctor must be consulted on the same day. Medical advice is particularly needed if the symptoms severely impair well-being and there is a risk of serious complications. For example, enlarged lymph nodes, stiffness of the neck and severe pain should be examined and treated immediately. Signs of increased intracranial pressure and seizures require emergency medical attention. The affected person or a first aider should call in the ambulance service and provide accompanying first aid. Subsequently, the sufferer must spend several days to weeks in hospital, depending on how hemophagocytic lymphohistiocytosis progresses and the underlying cause. People who have had a viral illness or parasitic infection are particularly susceptible to immune system disease. Patients with systemic lupus or rheumatoid arthritis should also talk to the appropriate physician if they have symptoms mentioned above.
Treatment and therapy
Primary hemophagocytic lymphohistiocytosis can be treated and cured exclusively by stem cell transplantation. This is because the stimulation of macrophages is stopped in this way. In the secondary form of hemophagocytic lymphohistiocytosis, the focus is on treating the underlying disease. Infections or autoimmune diseases are often responsible for the development of hemophagocytic lymphohistiocytosis. Here, the drug dexamethasone is used together with etoposide. If hemophagocytosis still occurs, a so-called maintenance therapy is started. This consists of the administration of etoposide, dexamethasone pulses as well as the substance cyclosporin A. Basically, the prognosis of the disease is highly dependent on the causative disease.
Prevention
Potential measures for prevention of hemophagocytic lymphohistiocytosis are not known. In the case of the primary form of the disease, preventive measures are excluded in principle due to the genetic causes. The secondary form can be prevented to the extent that prevention of the underlying diseases is possible.
Follow-up
In hemophagocytic lymphohistiocytosis, maintenance therapy with drugs takes place after initial treatment. Further measures depend on the disease that triggered this clinical picture. There is no preventive therapy for the primary disease, as it is genetically determined.In a secondary form, only preventive measures are possible in relation to the underlying disease. The focus is therefore on early treatment by a doctor. Patients should therefore make an appointment quickly so that they can recover as quickly as possible. The typical complaints are fever, severe headaches and skin rashes. They reduce the quality of life and make patients more susceptible to everyday stresses. In some cases, those affected can hardly perform their normal duties. However, after taking the correct remedies prescribed by the doctor, their condition improves after a recovery period. Immune forces are greatly reduced for the time being, so patients should take care of their bodies and not engage in sports. At the same time, it is important to pay attention to possible interactions between the various medications. Soothing ointments and thorough hygiene are helpful against the rashes. If severe seizures occur, an emergency physician should be called.
This is what you can do yourself
Since hemophagocytic lymphohistiocytosis is a serious disease, the first priority is not self-help but timely medical treatment. In order to improve their state of health and regain the quality of life to which they are accustomed, those affected seek medical attention as soon as possible at the first symptoms. Patients suffer from unpleasant symptoms such as fever, headaches and rashes on the skin. As a result, sufferers are less able to cope with stress and are often no longer able to perform their everyday duties. To improve their own health, patients take the medications prescribed by their doctor as instructed and rest at home. During the disease, the immune system is reduced, and patients also refrain from sports and other physical exertion. Due to the large number of symptoms, different medications usually have to be taken, so patients also pay attention to possible interactions between the active ingredients. The skin rashes can sometimes be alleviated by ointments, although care must also be taken to ensure sensitive hygiene of the areas. In case of severe seizures, which are quite common in hemophagocytic lymphohistiocytosis, patients call an emergency physician. The social environment should be informed about the disease.