Make An Appointment: About Histiocytosis Histiocytosis, also referred to as Langerhans Cell Histiocytosis LCH , and formally called Histiocytosis X, represents a group of rare disorders involving specific cells that normally have important roles as part of the immune system. Histiocytosis is a generic name for a group of syndromes characterized by an abnormal increase in the number of certain immune cells called histiocytes. These include monocytes, macrophages, and dendritic cells. A histiocyte is a normal immune cell that is found in many parts of the body especially in the bone marrow, the blood stream, the skin, the liver, the lungs, the lymph glands and the spleen.
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Make An Appointment: About Histiocytosis Histiocytosis, also referred to as Langerhans Cell Histiocytosis LCH , and formally called Histiocytosis X, represents a group of rare disorders involving specific cells that normally have important roles as part of the immune system.
Histiocytosis is a generic name for a group of syndromes characterized by an abnormal increase in the number of certain immune cells called histiocytes.
These include monocytes, macrophages, and dendritic cells. A histiocyte is a normal immune cell that is found in many parts of the body especially in the bone marrow, the blood stream, the skin, the liver, the lungs, the lymph glands and the spleen. In histiocytosis, the histiocytes move into tissues where they are not normally found and cause damage to those tissues. These proliferating immune cells may form tumors, which can affect various parts of the body. LCH is often classified as single system, when the disease affects only one part of the body, or multisystem, when it affects more than one part of the body.
In children, histiocytosis usually involves the bones and may consist of single or multiple sites. The skull is frequently affected. Children over five years of age usually have the single system disease, with just bone involvement.
Young children, especially infants, are more likely to have the multisystem disease. Most cases of histiocytosis affect children between the ages of one and 15 years, although people of all ages can develop LCH. The incidence peaks among children between 5 and 10 years old. Histiocytosis is thought to affect roughly one to two out of , people each year. The exact cause of histiocytosis is unknown. However, recent studies indicate that it is caused by the development and expansion of an abnormal Langerhans cell that subsequently leads to the accumulation of other cells of the immune system, resulting in collections or tumors in various areas of the body.
Some forms are genetic. Histiocytosis Symptoms The first sign of histiocytosis is often a rash on the scalp, similar to cradle cap. There may be a pain in a bone, discharge from the ear, loss of appetite and fever. Sometimes the stomach is swollen and painful. Occasionally, an area of the brain known as the pituitary gland is affected, and this can lead to the child passing large amounts of urine and being very thirsty.
The tumors produce a "punched-out" appearance on bone X-rays. Sometimes, children experience spontaneous fractures as a result of these bone lesions. There is often systemic involvement as well, which may affect the whole body and cause rashes, lung problems, gum infiltration, lymph gland swelling, hormonal problems, enlargement of the spleen and liver, and anemia.
These tests will help the doctor determine if the disease is the single system or multisystem type. An X-ray of the entire skeletal system may be done to determine how extensive the disease is and whether or not the systemic involvement is indicated. Histiocytosis Treatment Depending on the extent of the disease, LCH is often treated with chemotherapy and steroids to suppress the function of the immune system and the production of histiocytes.
The length of treatment will vary from child to child. Many patients are eligible for international as well as local institutional trials. Radiation therapy , treatment with targeted X-rays, or limited surgery may also be used to treat bone lesions in some situations. The majority of patients who develop histiocytosis have complete recoveries.
Sometimes the disease can recur, so the patient will have regularly scheduled follow-up visits in the outpatient clinic as a precaution.
Histiocytosis Research New ideas are being tested to determine the causes of LCH as well as why some patients respond better to treatment than others. New types of therapies are being developed, including new types of drugs, as are approaches that direct antibodies or small molecules to the abnormal Langerhans cell while sparing the normal tissues. These lesions sometimes involute spontaneously and no treatment is required. Occasionally there is systemic involvement.
When this occurs therapy similar to that for LCH is used. When the disease is disseminated, it can be referred to as xanthoma disseminatum. ECD is characterized by accumulations of xanthomatous macrophages particularly in the retroperitoneum which often can lead to renal failure.
In addition, ECD commonly affects the lungs heart along with bilateral long bone involvement leading to severe and chronic pain. Treatment for patients with ECD usually involves alpha-interferon or treatments similar to those used to treat patients with LCH. Diagnosis is made by a biopsy. Twenty percent of patients have spontaneous resolution or improvement within 3—9 months. The majority of patients have stable and persistent disease lasting up to several years.
No treatment is generally warranted because this it is a self-limited disease. However, when patients require treatment, steroids along with chemotherapy and sometimes, alpha-interferon are used.
Familial hemophagocytic lymphohistiocytosis FHLH familial or sporadic : This is an autosomal-recessive disease that affects immune regulation.
Hermansky-Pudlak syndrome has been reported to be associated with HLH. FHLH is inherited as an autosomal recessive disorder. The age of onset is usually less than 1 year of age. Signs and symptoms of FHLH include: a. Fever, splenomegaly and hepatomegaly are the most common early findings; b. Neurologic findings including irritability, bulging fontanel, neck stiffness, hypotonia, hypertonia, convulsions, cranial nerve palsies, ataxia, hemiplegia, blindness, and unconsciousness; 3.
Multisystem involvement includes lungs, bone marrow, and leptomeninges. Occasionally, ocular, heart, skeletal muscles, and kidney involvement have been noted. Patients should be treated as per modern protocols e. Non-familial disease is initially and commonly treated in a similar manner. Without treatment, FHLH is usually rapidly fatal, with a median survival of about 2 months.
Chemotherapy and immunosuppressive therapy may prolong survival in FHLH but only stem cell transplantation may be curative. Patients with known familial disease or severe or persistent acquired disease should then receive hematopoietic stem cell transplantation. These are usually quite aggressive diseases and clinically behave like different types of lymphoma.
Pateints are usually best treated with combinations of chemotherapy, such as used for lymphoma and aggressive histiocytic disorders. For localized disease, sometimes surgery with or without radiation therapy, are effective. Request an Appointment.
Langerhans Cell Histiocytosis, Hashimoto-Pritzker Type Langerhans Cell Histiocytosis of lung Langerhans Cell Histiocytosis, disseminated clinical Langerhans Cell Histiocytosis, unifocal clinical The disease spectrum results from clonal accumulation and proliferation of cells resembling the epidermal dendritic cells called Langerhans cells , sometimes called dendritic cell histiocytosis. These cells in combination with lymphocytes , eosinophils , and normal histiocytes form typical LCH lesions that can be found in almost any organ. LCH is clinically divided into three groups: unifocal, multifocal unisystem, and multifocal multisystem. It typically has no extraskeletal involvement, but rarely a lesion can be found in the skin, lungs, or stomach.
Langerhans cell histiocytosis