What is Histiocytosis?

Histiocytosis is an umbrella term which refers to a family of medical conditions characterized by abnormally high levels of histiocytes in the blood and tissues. These cells, normally part of the immune system, begin to attack the body, targeting organs, bone, and tissue. In some forms of histiocytosis, patients develop tumors in their body as a result of a proliferation of malignant cells. The prognosis for a patient with histiocytosis varies, depending on which form the patient has and when it is diagnosed.

There are three categories within this family of diseases: Langerhans histiocytosis, non-Langerhans forms, and malignant histiocytosis. Some have a clear genetic component and have been linked to specific genes and populations, while the origins of others are more obscure. Some researchers theorize that these diseases may be caused by genetic abnormalities, and others have suggested that histiocytosis, at least in some forms, may actually be autoimmune in origin.

The onset of histiocytosis usually occurs in childhood. Symptoms can include fatigue, pain, difficulty breathing, weight loss, sweating, recurrent infections, and vision problems. Testing such as blood tests can reveal unusually high levels of histiocytes, and medical imaging studies can be conducted to look for signs of damage in the body caused by the rogue cells. A biopsy may also be taken to collect a sample from an area of interest to learn more about the situation.

Depending on the form of the disease a patient has, a variety of medications can be prescribed to cope with the situation. Chemotherapy and radiation are sometimes successful at reducing the numbers of histiocytes, and surgery can be utilized to remove malignant growths associated with the condition, if a patient has them. In some cases, especially with diseases with a clear genetic component, the condition may be fatal, with the focus in treatment being management and improving the patient's quality of life as much as possible.

When someone is diagnosed with histiocytosis, it is important to ask about which form of the condition is involved. Understanding which type a patient has is important when considering treatment options and the prognosis. A doctor should be able to provide recommendations about treatment and a reasonable prognosis for the patient, or to refer a patient to a care provider who can answer questions and provide treatment and support. Because treatments can be quite varied, patients may find it beneficial to consult with several doctors before selecting one to oversee treatment.