• Langerhans cell histiocytosis (LCH) is a group of idiopathic disorders characterized by the presence of cells with characteristics similar to bone marrow-derived Langerhans cells juxtaposed against a backdrop of hematopoietic cells, including T-cells, macrophages, and eosinophils. (medscape.com)
  • The term Langerhans cell histiocytosis is generally preferred to the older term, histiocytosis X. This newer name emphasizes the histogenesis of the condition by specifying the type of lesional cell and removes the connotation of the unknown ("X") because its cellular basis has now been clarified. (medscape.com)
  • The working group of the Histiocyte Society divided histocytic disorders into three groups: (1) dendritic cell histiocytosis, (2) macrophage-related disorders, and (3) malignant histiocytosis. (medscape.com)
  • More recently, histiocytic diseases have been reclassified into five groups: (1) Langerhans-related, (2) cutaneous and mucocutaneous, (3) malignant histiocytosis, (4) Rosai-Dorfman disease, and (5) hemophagocytic lymphohistiocytosis and macrophage activation syndrome. (medscape.com)
  • The pathogenesis of Langerhans cell histiocytosis (LCH) is unknown. (medscape.com)
  • Non-Langerhans cell histiocytosis refers to a family of histiocytosis characterized by the absence of Langerhans cells. (wikipedia.org)
  • The spectrum of non-langerhans cell histiocytoses include: Benign cephalic histiocytosis Generalized eruptive histiocytoma Indeterminate cell histiocytosis Juvenile xanthogranuloma Progressive nodular histiocytoma Necrobiotic xanthogranuloma (Giant Cell) Reticulohistiocytoma Multicentric reticulohistiocytosis Rosai-Dorfman disease Xanthoma disseminatum Kikuchi disease Erdheim-Chester disease. (wikipedia.org)
  • No consensus exists for the optimal therapy for Langerhans cell histiocytosis (LCH), particularly in the case of multisystem organ disease. (medscape.com)
  • Single-agent chemotherapy with cladribine (2-chlorodeoxyadenosine/2-CdA) may be a promising treatment for single-system pulmonary Langerhans cell histiocytosis. (medscape.com)
  • Opsin 3 expression in human Langerhans cell histiocytosis and its mediation of ELD-1 cellular function. (bvsalud.org)
  • Langerhans cell histiocytosis (LCH) is a type of -histiocytic disorder characterized by aberrant function, differentiation or proliferation of mononuclear phagocyte system cells , however, the pathogenesis is not fully understood. (bvsalud.org)
  • Juvenile xanthogranuloma Langerhans cell histiocytosis (LCH) is a proliferation of dendritic mononuclear cells with infiltration into organs locally or diffusely. (msdmanuals.com)
  • Currently, the preferred term is Langerhans cell histiocytosis. (thedoctorsdoctor.com)
  • Langerhans cell histiocytosis presenting in the neonatal period: a retrospective case series. (thedoctorsdoctor.com)
  • OBJECTIVES: To describe the morphologic characteristics of skin lesions, extent of extracutaneous disease, and outcomes in patients with neonatal presentation of Langerhans cell histiocytosis (LCH), and to examine clinical predictors of disease prognosis. (thedoctorsdoctor.com)
  • Epidemiologic study of Langerhans cell histiocytosis in children. (thedoctorsdoctor.com)
  • OBJECTIVE: The etiology and pathogenesis of Langerhans cell histiocytosis (LCH) remain poorly understood. (thedoctorsdoctor.com)
  • We present a case of multiorgan, multisite Langerhans cell histiocytosis (LCH), positive for the oncogenic BRAF V600E mutation, in a preterm neonate. (thieme-connect.de)
  • Here, we outline the most likely diagnoses with this presentation and discuss a case of Langerhans cell histiocytosis (LCH) in a preterm neonate with severe multiorgan involvement. (thieme-connect.de)
  • Histiocytosis X was renamed Langerhans-cell histiocytosis , reflecting the concept that LCH cells represented dysfunctional epidermal Langerhans cells. (capsulehealth.one)
  • Available at: http://www.cancernetwork.com/oncology-journal/langerhans-cell-histiocytosis-emerging-insights-and-clinical-implications [Accessed 1 Jul. (capsulehealth.one)
  • Some researchers believe that langerhans cell histiocytosis in children is a malignant disease, while others consider this form of histiocytosis as a non-tumor process. (antibiotic-store.com)
  • Localized histiocytosis is known as eosinophilic granuloma, as well as Langerhans cell granuloma. (antibiotic-store.com)
  • To date, it has been proven that the proliferation process (neoplasm of cells and intracellular structures - mitochondria, endoplasmic reticulum, ribosomes, etc.) of Langerhans cells with histiocytosis X is characterized by a monoclonal (belonging to the same cell clone) character. (antibiotic-store.com)
  • Sinus histiocytosis with massive lymphadenopathy (SHML), initially described in 1969 by Rosai and Dorfman,[ 22 ] is a rare, nonneoplastic lymphoproliferative disorder that is characterized by its histological features. (surgicalneurologyint.com)
  • Histiocytosis is an umbrella term for an emerging spectrum of "syndromes" or disorders that involve abnormal proliferation of specialized white blood cells (histiocytes). (petmoo.com)
  • C group: Non-Langerhans Cell Histiocytosis (skin). (petmoo.com)
  • L group: Erdheim-Chester Disease, Langerhans Cell Histiocytosis, etc. (petmoo.com)
  • Malignant histiocytic diseases include malignant histiocytosis (now it is called localized and disseminated histiocytic sarcoma) and cutaneous histiocytoma, which is a benign histiocytic tumor. (petmoo.com)
  • Histiocytosis UK is dedicated to promoting and funding scientific research into uncovering not only the causes of all histiocytic diseases, which include Langerhans's Cell Histiocytosis and Haemophagocytic Lymphohistiocytosis, but also ensuring early diagnosis, effective treatment and a cure. (histiouk.org)
  • An International team of Researchers including researchers from Newcastle, Dr Paul Milne and Prof Matthew Collin have made progress in understanding how the childhood cancer Langerhans Cell Histiocytosis (LCH) damages tissue in the body. (histiouk.org)
  • This work represents an important advance in understanding how the lesions of Langerhans Cell Histiocytosis develop. (histiouk.org)
  • When asked "What does it mean for our paediatric patients of Langerhans Cell Histiocytosis? (histiouk.org)
  • Sakata N, Toguchi N, Kimura M, Nakayama M, Kawa K, Takemura T. Development of Langerhans cell histiocytosis associated with chronic active Epstein-Barr virus infection. (mayabouchenaki.com)
  • Murakami I, Gogusev J, Fournet JC, Glorion C, Jaubert F. Detection of molecular cytogenetic aberrations in langerhans cell histiocytosis of bone. (mayabouchenaki.com)
  • Erdem AP, Kasimoglu Y, Sepet E, Gencay K, Sahin S, Dervisoglu S. Oral manifestations may be the first sign of Langerhans cell histiocytosis. (mayabouchenaki.com)
  • Juvenile xanthogranuloma is a rare non-Langerhans cell histiocytosis that usually occurs during infancy and early childhood. (biomedcentral.com)
  • Langerhans cell histiocytosis (LCH) is a disease characterized by the abnormal proliferation of leukocytes in the liver, lung and spleen. (histio.org)
  • Idiopathic non-malignant disease characterized by idiopathic infiltration and accumulation of abnormal histiocytes (i.e. the Langerhans cells) within various tissues (bone marrow, skin, central nervous system, lung, liver, spleen, lymph nodes) causing focal or systemic effects. (capsulehealth.one)
  • This disease is characterized by enhanced proliferation (reproduction of cellular elements) of histiocytes, as well as their accumulation in different tissues and the formation of granulomas. (antibiotic-store.com)
  • This mutation leads to production of a BRAF protein that is abnormally active, which disrupts regulation of cell proliferation and may allow histiocytes to grow and divide uncontrollably, leading to the abnormal accumulation of histiocytes that occurs in Erdheim-Chester disease. (medlineplus.gov)
  • A cutaneous histiocytoma is an abnormal proliferation of histiocytes in Langerhans cells. (petmoo.com)
  • Juvenile xanthogranuloma (JXG) is a benign, self-limiting reactive prolif- erative disorder of non-Langerhans cell histiocytes seen predominantly in infants and young children and occa- sional y in adults. (who.int)
  • [ 3 ] Taken together, these findings have led some to speculate that LCH is not a specific disease of epidermal Langerhans cells, but rather one of mononuclear phagocyte dysregulation. (medscape.com)
  • [ 3 , 4 ] Langerhans cells are stellate dendritic cells that arise from CD34-positive bone marrow stem cells [ 5 ] and are not a member of the mononuclear phagocytic system. (medscape.com)
  • At this point, Birbeck granules were thought to be exclusive to epidermal Langerhans cells, skin-restricted cells of the mononuclear phagocyte system. (capsulehealth.one)
  • Notably, LCH cells have been found to express markers of both resting epidermal Langerhans cells (CD1a, intracellular major histocompatibility complex II [MHCII], Birbeck granules) and activated Langerhans cells (including CD54 and CD58). (medscape.com)
  • Therefore, in addition to epidermal Langerhans cells, other potential cellular origins for LCH include dermal langerin + dendritic cells, lymphoid tissue-resident langerin + dendritic cells, and monocytes that can be induced by local environmental stimuli to acquire a Langerhans cell phenotype. (medscape.com)
  • We now know that epidermal Langerhans cells are not nerves but dendritic cells, a heterogeneous group of hematopoietic cells enriched in interface tissues and lymphoid organs. (capsulehealth.one)
  • Epidermal Langerhans cells are unique among dendritic cells in that they arise not from myeloid progenitor cells in bone marrow but rather from yolk-sac progenitors and fetal liver-derived monocytes that populate the skin before birth and are maintained locally under steady-state conditions. (capsulehealth.one)
  • Rosai-Dorfman disease (RDD) is an uncommon, benign histiocytic proliferative disorder of unknown origin. (surgicalneurologyint.com)
  • In 1868, Paul Langerhans discovered the epidermal dendritic cells that now bear his name. (medscape.com)
  • Langerhans cells are named after Paul Langerhans , a bright, young medical student who worked with the new technique of gold colloid staining in the mid-19th century. (capsulehealth.one)
  • Histiocytic infiltration and proliferation within the synovium is a common finding associated with inflammatory processes. (medscape.com)
  • As a result of such normal processes, the lymph nodes can enlarge through either proliferation of normal cells or infiltration by abnormal cells. (medscape.com)
  • The ultrastructural hallmark of the Langerhans cell, the Birbeck granule, was described a century later. (medscape.com)
  • Although the epidermal Langerhans cell has been presumed to be the cell of origin in LCH, recent studies have called this belief into question. (medscape.com)
  • We report an unusual case of Langerhans cell granulomatosis (LCG) manifested as a villous synovial proliferation in a 38-year-old female jogger. (medscape.com)
  • Langerhans cell granulomatosis (LCG) is a clonal disorder characterized by lesions containing histiocyte-like cells, giant cells, and eosinophils. (medscape.com)
  • Langerhans cell granulomatosis cells are abnormal and coexpress S100 and CD1a, and these markers are used to separate this subpopulation of dendritic cells from other histiocyte-like cells. (medscape.com)
  • It emphasizes the importance of immunocytochemistry to separate this histiocyte-like cell proliferation from true histiocytic and other dendritic cell types. (medscape.com)
  • Cite this: Langerhans Cell Granulomatosis Manifested as Pigmented Villonodular Synovitis - Medscape - Dec 01, 2001. (medscape.com)
  • We aimed to investigate OPN3 expression in LCH and Langerhans cells and evaluate its possible regulation of cellular function in a Langerhans cell -like cell line (ELD-1). (bvsalud.org)
  • The effects of reduced or over-expressed OPN3 mRNA level, via a lentiviral vector, were examined on ELD-1 proliferation, migration, cell cycle and apoptosis using the Cell Counting Kit 8, EdU-594 kit, Transwell assays and Cell Cycle Analysis Kit and Annexin V -PE apoptosis kit, respectively. (bvsalud.org)
  • Knockdown of OPN3 in ELD-1 inhibited cell proliferation , the cell cycle , and cell migration , while over-expression reversed these processes. (bvsalud.org)
  • Broadly speaking, they can be divided into Langerhans and non-Langerhans cell histiocytoses. (thedoctorsdoctor.com)
  • Langerhans cell histiocytoses are all defined by the presence of a unique ultrastructural organelle, the Birbeck granule. (thedoctorsdoctor.com)
  • In 1868 , Langerhans described an epidermal cell population, accounting for approximately 1% of epidermal cells, with characteristic dendrites that he described as extracutaneous nerves. (capsulehealth.one)
  • Specifically, the RAS/MAPK pathway regulates the growth and division (proliferation) of cells, the process by which cells mature to carry out specific functions (differentiation), cell movement (migration), and the self-destruction of cells (apoptosis). (medlineplus.gov)
  • This mutation leads to production of a BRAF protein that is abnormally active, which disrupts regulation of cell proliferation. (medlineplus.gov)
  • The unregulated cell proliferation of early melanocytes leads to a large patch of darkly pigmented skin characteristic of giant congenital melanocytic nevus. (medlineplus.gov)
  • Rosai-Dorfman disease is a rare disorder characterized by overproduction (proliferation) and accumulation of a specific type of white blood cell (histiocyte) in the lymph nodes of the body (lymphadenopathy), most often those of the neck (cervical lymphadenopathy). (rarediseases.org)
  • LCH is characterized by the proliferation of CD1a-positive activated Langerhans (not atypical Langerhans cell, morphologically)-like cells (LCH cells) generating inflammatory granuloma. (mayabouchenaki.com)
  • Histiocytic/dendritic proliferations involving the synovial tissues are not uncommon. (medscape.com)
  • Histiocytic infiltrates also contain plasmocytes, eosinophils, proliferated reticular fibers and lymphocytes, which leads to pneumofibrosis. (antibiotic-store.com)
  • The presence of single or multiple raised cutaneous lesions characterize this self-healing disorder. (biomedcentral.com)
  • Juvenile xanthogranuloma is a benign and self-healing disorder which is characterized by the presence of single or multiple raised cutaneous nodules, yellow-brown to reddish in color and usually measuring from a few millimeters to a few centimeters in diameter. (biomedcentral.com)
  • These lesions as well as the rare multicentric reticulohistiocytosis (MRH), a systemic monocytoid/histiocytic disorder with multinucleated giant cells, polyarthritis, and papulonodular skin lesions, should be considered in the differential diagnosis. (medscape.com)
  • The cellular makeup of these monocytoid/histocytic cells is heterogeneous and ranges from cells of lymphoid, histiocytic, and dendritic origin. (medscape.com)
  • The histiocytic disease differentiation can be challenging. (petmoo.com)
  • In the mid-1900s, Farber and Lichtenstein noted that biopsy specimens from cases of fatal Letterer-Siwe disease and specimens from cases of clinically mild eosinophilic granuloma were indistinguishable, and the two pathologists hypothesized that these conditions represent manifestations of a common disorder. (capsulehealth.one)
  • This article provides a rational approach to determining the etiology of the lymph node disorder, highlights various disorders to consider in treating a child with lymphadenopathy, and discusses various means of obtaining a tissue diagnosis when the cause of lymphadenopathy is uncertain. (medscape.com)
  • Specifically, a variety of other cellular populations have been identified that possess phenotypic characteristics similar to Langerhans cells, including expression of CD207 and Birbeck granules. (medscape.com)
  • Langerhans cells are dendritic antigen-presenting cells. (capsulehealth.one)
  • The abnormal cells in LCH have abnormal proliferation and lower antigen-presenting capability. (capsulehealth.one)
  • Langerhans cells (LC) are members of the dendritic cells family, residing in the basal and suprabasal layers of the epidermis and in the epithelia of the respiratory, digestive and urogenital tracts. (mayabouchenaki.com)
  • Langerhans cells are dendritic but unpigmented and are found nearer the skin surface than melanocytes. (mayabouchenaki.com)
  • One of the key cellular components with functional roles in both innate and adaptive arms of the immune response are Langerhans cells (LCs) (2). (mayabouchenaki.com)
  • The histopathologic diagnosis of the lingual neoformation was histiocitary proliferation with the presence of giant cells, Touton type, compatible with juvenile xanthogranuloma. (biomedcentral.com)
  • They acquire mucosa-associated lymphoid tissue (MALT) type as a result of an immunologically mediated disorder. (lookformedical.com)
  • The disorder predominantly affects children, adolescents or young adults. (rarediseases.org)
  • The P253R variant in FGFR2 has also been described in some constitutional disorders including craniosynostosis syndromes (eg, Apert syndrome). (cornell.edu)
  • Pneumofibrosis is a disease characterized by proliferation of the connective tissue of the lung due to the inflammatory process, which causes a violation of the structure of the lungs and a decrease in their ventilation function. (antibiotic-store.com)
  • The symptoms and physical findings associated with Rosai-Dorfman disease vary greatly from one person to another depending upon the extent of the disorder and the specific organ systems affected. (rarediseases.org)
  • Many individuals with Rosai-Dorfman disease do not develop any additional symptoms of the disorder (asymptomatic). (rarediseases.org)
  • At least 49 BRAF mutations have been identified in people with this disorder. (medlineplus.gov)
  • Histiocytic disorders of children and adults: introduction to the problem, overview, historical perspective and epidemiology. (mayabouchenaki.com)