What does Histiocytic reaction mean?
A group of rare disorders in which too many histiocytes (a type of white blood cell) build up in certain tissues and organs, including the skin, bones, spleen, liver, lungs, and lymph nodes. This can cause damage to tissue or tumors to form in one or more parts of the body.
What is histiocytic inflammation?
Histiocytoses are disorders characterised by inflammation and the accumulation of cells derived from the monocyte and macrophage lineages, which results in tissue damage.
What are the different presentations of histiocytosis?
Langerhans cell histiocytosis formerly was divided into 3 disease categories: eosinophilic granuloma, Hand-Schüller-Christian disease, and Letterer-Siwe (or Abt-Letterer-Siwe) disease, depending on the severity and extent of involvement. This classification and its related risk groups no longer are used.
What does Histiocytic mean in medical terms?
Medical Definition of histiocytosis : abnormal multiplication of macrophages Langerhans cell histiocytosis broadly : a condition characterized by such multiplication.
What does Histiocytic mean?
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.
What causes Histiocytic inflammation?
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.
Is histiocytosis an autoimmune disease?
Langerhans cell histiocytosis historically was thought of as a cancer-like condition, but more recently researchers have begun to consider it an autoimmune phenomenon in which immune cells begin to overproduce and attack the body instead of fighting infection.
What do histiocytes look like?
Histiocytes (Macrophages) In smears, the typical histiocyte is easily identified by its size, eccentric round or bean-shaped nucleus, and lightly stained lacy cytoplasm (Fig. 19.43). Because histiocytes are phagocytic, their cytoplasm may contain leukocytes, nuclear particles (Fig.
What are the symptoms of histiocytosis?
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.
How do histiocytes look?
Is histiocytosis fatal?
Langerhans cell histiocytosis can cause damage to tissues and organs all over the body if it’s not treated. One example is pulmonary histiocytosis. This condition damages the lungs. Damage to the body can be so severe that the condition becomes fatal.
What does a histiocyte do?
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.