Histiocytosis
Encyclopedia
In medicine
, histiocytosis refers to an excessive number of histiocyte
s, (tissue macrophages), and is typically used to refer to a group of rare diseases which share this as a characteristic. Occasionally and confusingly, the term "histiocytosis" is sometimes used to refer to individual diseases.
The histiocytes may attack skin, bone, muscles, and other important organs, including the liver, lung, spleen, and hematopoietic system. The disease is somewhat similar to cancer
, and treatment often involves radiation and chemotherapy
.
According to the Histiocytosis Association of America, 1 in 200,000 children in the United States
are born with histiocytosis each year. HAA also states that most of the people diagnosed with histiocytosis are children under the age of 10. The University of California, San Francisco
, states that the disease usually occurs from birth to age 15.
Histiocytosis (and malignant histiocytosis
) are both important in veterinary as well as human pathology.
, they can be divided into three categories. However, the classifications in ICD10 and MeSH are slightly different, as shown below:
Types of LCH have also been known as "Eosinophilic Granuloma", "Hand-Schuller-Christian Disease", "Letterer-Siwe Disease", and "Histiocytosis X". (See Langerhans cell histiocytosis
for details).
Alternatively, histiocytoses may be divided into the following groups:
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, histiocytosis refers to an excessive number of histiocyte
Histiocyte
A histiocyte is a cell that is part of the mononuclear phagocyte system . The mononuclear phagocytic system is part of the organism's immune system...
s, (tissue macrophages), and is typically used to refer to a group of rare diseases which share this as a characteristic. Occasionally and confusingly, the term "histiocytosis" is sometimes used to refer to individual diseases.
The histiocytes may attack skin, bone, muscles, and other important organs, including the liver, lung, spleen, and hematopoietic system. The disease is somewhat similar to cancer
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
, and treatment often involves radiation and chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
.
According to the Histiocytosis Association of America, 1 in 200,000 children in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
are born with histiocytosis each year. HAA also states that most of the people diagnosed with histiocytosis are children under the age of 10. The University of California, San Francisco
University of California, San Francisco
The University of California, San Francisco is one of the world's leading centers of health sciences research, patient care, and education. UCSF's medical, pharmacy, dentistry, nursing, and graduate schools are among the top health science professional schools in the world...
, states that the disease usually occurs from birth to age 15.
Histiocytosis (and malignant histiocytosis
Malignant histiocytosis
Malignant histiocytosis is a rare hereditary disease found in the Bernese Mountain Dog and humans, characterized by histiocytic infiltration of the lungs and lymph nodes. The liver, spleen, and central nervous system can also be affected. Histiocytes are a component of the immune system that...
) are both important in veterinary as well as human pathology.
Classification, and relationships to other conditions
There are competing systems for classifying histiocytoses. According to the 1999 classification proposed by the World Health OrganizationWorld Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
, they can be divided into three categories. However, the classifications in ICD10 and MeSH are slightly different, as shown below:
| Name | WHO | ICD10 | MeSH Medical Subject Headings Medical Subject Headings is a comprehensive controlled vocabulary for the purpose of indexing journal articles and books in the life sciences; it can also serve as a thesaurus that facilitates searching... >- | Langerhans cell histiocytosis Langerhans cell histiocytosis Langerhans cell Histiocytosis is a rare disease involving clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes... (LCH) |
I | >- | II | >- | II | >- | II | >- | II | - | >- | III | >- | III | >- | II | malignant histiocytic disorders |
Types of LCH have also been known as "Eosinophilic Granuloma", "Hand-Schuller-Christian Disease", "Letterer-Siwe Disease", and "Histiocytosis X". (See Langerhans cell histiocytosis
Langerhans cell histiocytosis
Langerhans cell Histiocytosis is a rare disease involving clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes...
for details).
Alternatively, histiocytoses may be divided into the following groups:
- X-type histiocytoses
- Non-X histiocytoses
Common treatments
- Chemotherapy
- CladribineCladribineCladribine is a drug used to treat hairy cell leukemia and multiple sclerosis. Its chemical name is 2-chlorodeoxyadenosine ....
(also known as 2CDA or Leustatin) - EtoposideEtoposideEtoposide phosphate is an anti-cancer agent. It is known in the laboratory as a topoisomerase poison. Etoposide is often incorrectly referred to as a topoisomerase inhibitor in order to avoid using the term "poison" in a clinical setting...
- VinblastineVinblastineVinblastine is an antimicrotubule drug used to treat certain kinds of cancer, including Hodgkin's lymphoma, non-small cell lung cancer, breast cancer, head and neck cancer, and testicular cancer. It is also used to treat Langerhan cell histiocytosis....
(Velban)
- Cladribine