X-type histiocytoses are a clinically well-defined group of cutaneous syndromes characterized by infiltrates of
Langerhans cell
A Langerhans cell (LC) is a tissue-resident macrophage of the skin once thought to be a resident dendritic cell. These cells contain organelles called Birbeck granules. They are present in all layers of the epidermis and are most prominent in t ...
s, as opposed to
Non-X histiocytosis in which the infiltrates contain
monocytes
Monocytes are a type of leukocyte or white blood cell. They are the largest type of leukocyte in blood and can differentiate into macrophages and monocyte-derived dendritic cells. As a part of the vertebrate innate immune system monocytes also i ...
/
macrophages
Macrophages (; abbreviated MPhi, φ, MΦ or MP) are a type of white blood cell of the innate immune system that engulf and digest pathogens, such as cancer cells, microbes, cellular debris and foreign substances, which do not have proteins that ...
.
Conditions included in this group are:
:*
Congenital self-healing reticulohistiocytosis
:*
Langerhans cell histiocytosis
Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells, abnormal cells deriving from bone marrow and capable of migrating from skin to lymph nodes.
Symptoms range from isolated bone lesions to multisystem d ...
See also
*
Non-X histiocytosis
*
Histiocytosis
In medicine, histiocytosis is an excessive number of histiocytes (tissue macrophages), and the term is also often used to refer to a group of rare diseases which share this medical sign, sign as a characteristic. Occasionally and confusingly, th ...
References
Monocyte- and macrophage-related cutaneous conditions
Histiocytosis
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