Histiocytosis X is a histiocytosis. The so-called Langerhans cells, which belong to the dendritic cells, are affected. Usually, the disease is benign, although some severe courses with fatal outcome are possible, especially in young children.
What is histiocytosis X?
Histiocytosis X is a tumor-like disease in which Langerhans cells increase in number in the form of granulomas. Langerhans cells should not be confused with pancreatic islets of Langerhans or Langhans cells. They are dendritic cells that have cytoplasmic extensions and therefore occasionally have a star-like appearance. The cytoplasmic extensions are used to search for antigens, which are then presented by them to T lymphocytes. In addition to presenting antigens, the mature Langerhans cells also stimulate T lymphocytes, among others. Langerhans cells originate from the bone marrow and are a component of the skin and mucous membranes. Their main function, along with macrophages, monocytes and B lymphocytes, is to present antigens and stimulate T lymphocytes. When they proliferate granulomatously, histiocytosis forms. The so-called Birbeck granules present themselves as X-bodies under the electron microscope. This is where the name histiocytosis X comes from. The disease occurs in three different forms and mostly affects children and adolescents. However, it is assumed that the disease in children often takes a particularly conspicuous course. In adults, a considerable number of unreported cases is likely. Histiocytosis X is diagnosed with a frequency of 1:200,000 to 1:2000,000, particularly in children.
Causes
The causes of histiocytosis X are not yet known. It occurs in lesions of the skin or mucous membranes. It is thought to be caused by an abnormal immune response. The disease does not represent a malignant tumor. The course is usually benign. However, fatal courses occur in young children with a particularly aggressive form of the disease. It is a nonheritable and noncontagious reactive disease.
Symptoms, complaints, and signs
Histiocytosis X is a disease whose course cannot be predicted. Each affected individual represents a unique case. In principle, the disease is benign. However, it can also take a very malignant course. In most cases, the granulomas are located in individual foci, although there are also forms of progression in which many organ systems are affected at the same time. Three forms of the disease are distinguished:
- The most common form is eosinophilic granuloma, with an incidence of 70 percent of cases. Eosinophilic granuloma occurs mainly between the ages of 5 and 20.
- Hand-Schüller-Christian granulomatosis usually affects children between the ages of three and five, and Abt-Letterer-Siwe granulomatosis affects children between the ages of one and three. In both of the latter forms of histiocytosis X, fatal courses are common.
- Abt-Letterer-Siwe syndrome is the most severe form of the disease. Its frequency is only about ten percent.
Infants experience fever, severe eczema, lymph node infiltration, anorexia, infiltration of the spleen and liver, anemia, bleeding tendency, increased susceptibility to infection, and pulmonary symptoms. If the disease is not treated, the course is 90 percent fatal. Hand-Schüller-Christian syndrome is also a serious disease that is often fatal. It is the second most common form of histiocytosis X, accounting for approximately 20 percent of cases. Affected children between two and five years of age suffer from skeletal changes of the skull, ribs or pelvis, strabismus (strabismus), loss of vision, loss of teeth in case of infiltration of the gums, chronic ear infections, hormonal disturbances in case of pituitary infiltration and possibly systemic infestation involving lungs, spleen, liver, skin and lymph nodes. In addition to unfavorable courses, however, spontaneous cures also occur. By far the most common form of histiocytosis X, eosinophilic granuloma, is usually benign and is characterized by painful tumors in the bones. Tumors in the stomach, skin, and lungs may also occur. All tumors can regress spontaneously.Otherwise, treatment by excision, radiation, and chemotherapy is very promising.
Diagnosis and disease progression
To diagnose histiocytosis X, dividing histiocytes are detected histopathologically in the skin. In this process, Langerhans granules can be visualized by electron microscopy. However, exact diagnosis can only be achieved by MRI or CT scans and biopsy of the affected organs.
Complications
In the worst case, histiocytosis X can lead to the death of the patient. In this case, children are particularly affected by a fatal outcome of the disease, which is why immediate treatment is necessary in them. If no treatment is initiated, histiocytosis X also leads to a fatal outcome. Patients suffer from reactive fever and anemia. Furthermore, the immune system is weakened and the susceptibility to infections is increased. Those affected become ill more often and also suffer from lung problems. The liver and spleen can also be damaged by the disease. It is not uncommon for children to suffer complete loss of vision and hearing damage as a result of Histiocytosis X. The patient’s everyday life is extremely restricted by these complaints and the quality of life is reduced enormously. The treatment of histiocytosis X always depends on the symptoms and complaints. Therefore, it is not possible to directly predict whether complications will occur. In most cases, however, surgical interventions are necessary to eliminate the symptoms. Life expectancy may also be reduced by histiocytosis X.
When should you see a doctor?
If the child complains of pain in the body for several hours or days for seemingly no reason, a doctor should be consulted to clarify the causes. If swelling occurs in the bones or skull without a previous fall or accident, these are warning signs that need to be investigated. If the swellings increase in size, a doctor must be consulted as soon as possible so that the causes can be determined. Because histiocytosis X can be fatal in severe cases, the child should be seen by a physician as soon as possible. A visit to the doctor is necessary if fever or breathing difficulties occur. If there is an unusual tendency to bleed from minor injuries, there is cause for concern. If abnormalities of the skeletal system can be noticed during stretching movements, the observations should be discussed with a physician. If there is loss of vision, problems or inflammation of the hearing organ, or skin changes, a physician is needed. If there are irregularities in the child’s digestion, abnormal behavior, and dental problems, a doctor should be consulted for further examination. Complaints in the spleen, stomach or lungs are unusual and should be investigated as well as treated. Although spontaneous recovery may occur with histiocytosis X, a visit to the physician for evaluation is advised even if symptoms are relieved.
Treatment and therapy
Treatment of histiocytosis X depends on the individual course of the disease. Some patients require no therapy at all because their symptoms resolve on their own. In other patients, however, cure is not possible without treatment. Local foci can be surgically removed and subsequently treated with radiotherapy and local cortisone administration. In most cases, however, surgery and radiation treatment are followed by mild chemotherapy to avoid late sequelae. Severe and extensive courses of the disease are often successfully treated with chemotherapy. The drugs administered are corticosteroids, interferon alpha and cytostatic drugs. In Abt-Letterer-Siwe syndrome, stem cell transplantation may need to be performed in addition to aggressive chemotherapy. Intensive chemotherapy is also often required for Hand-Schüller-Christian syndrome, although spontaneous recovery may even occur at times.
Outlook and prognosis
The prognosis of histiocytosis X depends on the particular form of progression. Although there are three forms of the disease such as eosinophilic granuloma, Abt-Letterer-Siwe syndrome, and Hand-Schüller-Christian syndrome. However, these cannot be considered separately. The individual manifestations are expressions of the same disease with different courses.Eosinophilic granuloma has the most favorable prognosis. It affects children and adolescents between 5 and 20 years of age and is characterized by a local course with multifocal foci. Eosinophilic granuloma is by far the most common form of histiocytosis X, accounting for approximately 70 percent of cases. The disease can often regress completely without treatment. In some cases, however, surgical intervention and radiation therapy are necessary. Abt-Letterer-Siwe syndrome is the most severe form of histiocytosis X, accounting for about 10 percent of all cases. The syndrome predominantly affects young children up to the age of two. In up to 90 percent of all cases, Abt-Letterer-Siwe syndrome is rapidly lethal. Only with intensive chemotherapy, which may have to be supplemented with stem cell therapy, is there still a chance of survival. The so-called Hand-Schüller-Christian syndrome occurs in about 5 to 40 percent of cases. It mostly affects younger children up to five years of age. This form of the disease often also heals spontaneously. However, in about 30 percent of those affected, there is a very poor prognosis due to systemic involvement of multiple organs.
Prevention
Measures to prevent histiocytosis X cannot yet be recommended because the causes of the disease are unknown. In addition, most disease occurs in early childhood. Milder forms in adulthood may be so inconspicuous that there must be a greater incidence of unreported cases.
Follow-up
Affected individuals with histiocytosis X usually first need a comprehensive examination and diagnosis by a physician. This is the only way to prevent further complications or discomfort. Therefore, in the case of histiocytosis X, the focus is on early detection and treatment of the disease to prevent further worsening of the symptoms. Self-cure may not occur, with very few measures or options for aftercare available to the affected person. In the worst case, the disease can lead to death if left untreated. The treatment of this disease is mostly done by taking medication. The affected person is also dependent on correct and, above all, regular use of the medication in order to permanently alleviate the symptoms and prevent further deterioration. Especially in the case of children, parents should pay attention to the correct intake of medication. Since the disease can also lead to the development of tumors, regular examinations by a doctor are very useful. In very rare cases, histiocytosis X may also heal spontaneously. However, in most cases, the life expectancy of the affected person is reduced by this disease.
What you can do yourself
Histiocytosis X does not need to be treated in every case. In some patients, the symptoms resolve on their own. However, self-help options are only available to the affected person with this disease to a very limited extent. Since many patients are dependent on chemotherapy, they need strong support during this therapy. This support should come primarily from the family and parents. Those affected can also be accompanied during their sessions. Furthermore, discussions with a therapist or a psychologist can prevent psychological complaints and depression. Of course, conversations with other affected patients are also suitable here. A direct prevention of the disease is not possible. Since those affected by histiocytosis X suffer from severe fever and an increased tendency to bleed, they should take it easy on their bodies and not engage in any strenuous activities. Any sports should also be avoided to prevent injuries. In the case of surgical procedures, the physician must be informed of the high bleeding tendency in any case in order to avoid complications. Due to the high susceptibility to infections and inflammations, increased hygiene measures are necessary to successfully avoid these as well.
