{"id":4422296,"date":"2025-01-11T12:38:54","date_gmt":"2025-01-11T18:38:54","guid":{"rendered":"https:\/\/myendoconsult.com\/learn\/topics\/langerhans-cell-histiocytosis\/"},"modified":"2025-01-13T06:49:02","modified_gmt":"2025-01-13T12:49:02","slug":"langerhans-cell-histiocytosis","status":"publish","type":"oen_topic","link":"https:\/\/myendoconsult.com\/learn\/topics\/langerhans-cell-histiocytosis\/","title":{"rendered":"Langerhans Cell Histiocytosis"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">LANGERHANS CELL HISTIOCYTOSIS (LCH) IN CHILDREN<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Definition and Pathophysiology<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Langerhans Cell Histiocytosis (LCH)<\/strong>:\n<ul class=\"wp-block-list\">\n<li>A disorder of <strong>Langerhans cells<\/strong>, which are bone marrow\u2013derived dendritic cells involved in antigen processing.<\/li>\n\n\n\n<li>In LCH, these cells lose the ability to present antigens, leading to immunologic dysfunction.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Normal Langerhans Cells<\/strong>: Found in the epidermis, lymph nodes, thymic epithelium, and bronchial mucosa.\n<ul class=\"wp-block-list\">\n<li>Migrate to lymphoid tissues and stimulate T-cell responses.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Incidence<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Rarity<\/strong>: Affects approximately <strong>3\u20135 children per million<\/strong> each year.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Clinical Presentations<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Localized Disease<\/strong>\n<ul class=\"wp-block-list\">\n<li>Common presenting sites include <strong>bone, skin, or lymph nodes<\/strong>.<\/li>\n\n\n\n<li><strong>Skin involvement in infants<\/strong>: Brown-purplish papules, often benign and self-healing in the first year of life.<\/li>\n\n\n\n<li>Later in infancy: Red papular rash on neck, axilla, abdomen, back, groin, and scalp.<\/li>\n\n\n\n<li>When skin-limited LCH is suspected, additional workup (CT of chest and abdomen, bone marrow biopsy) is warranted to rule out multisystem involvement.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Multisystem Disease<\/strong>\n<ul class=\"wp-block-list\">\n<li>May present later in childhood with more extensive involvement (e.g., liver, spleen, bone marrow).<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Bone Involvement<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Most Common Site<\/strong>: Skull (lytic lesions causing localized pain, swelling, and sometimes erythema).<\/li>\n\n\n\n<li>Other bones: Ribs, cervical vertebral bodies, humerus, femur.<\/li>\n\n\n\n<li><strong>Mass-Effect Presentations<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Skull base, maxillofacial bone, or sellar involvement \u2192 hearing loss, exophthalmos, <a href=\"https:\/\/myendoconsult.com\/learn\/mnemonic-cranial-nerves-dirty-surprise\/\"  data-wpil-monitor-id=\"77\">cranial nerve<\/a> palsies, diabetes insipidus (DI).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Skull Radiographs<\/strong>: May show irregular \u201cgeographic skull\u201d lesions.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Endocrine Manifestations<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/myendoconsult.com\/learn\/triphasic-response-of-diabetes-insipidus\/\"  data-wpil-monitor-id=\"79\">Diabetes Insipidus<\/a> (DI)<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Most common endocrine manifestation.<\/li>\n\n\n\n<li>Can be the initial presenting symptom.<\/li>\n\n\n\n<li>Often associated with anterior pituitary insufficiency and thickening of the <a href=\"https:\/\/myendoconsult.com\/learn\/pituitary-stalk-thickening\/\"  data-wpil-monitor-id=\"80\">pituitary stalk<\/a> on imaging.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Lymph Node Involvement<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Isolated Lymphadenopathy<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Usually in the cervical or mediastinal lymph nodes.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Diffuse Multisystem Disease<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Liver and Spleen<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Clotting factor deficiencies, increased bilirubin, low albumin (liver involvement).<\/li>\n\n\n\n<li>Splenomegaly can cause cytopenias.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Lung Involvement<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Cystic and nodular pattern on imaging.<\/li>\n\n\n\n<li>Pneumothorax may be an initial sign.<\/li>\n\n\n\n<li>Can lead to diffuse fibrosis, resulting in dyspnea.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Bone Marrow<\/strong>: Commonly affected in diffuse disease.<\/li>\n\n\n\n<li><strong>Central Nervous System<\/strong>: Ataxia, cognitive dysfunction if the cerebellum or basal ganglia are involved.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Historical Terminology<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Hand-Sch\u00fcller-Christian disease<\/strong>: LCH with prominent skull defects, DI, exophthalmos.<\/li>\n\n\n\n<li><strong>Letterer-Siwe disease<\/strong>: LCH with extensive multiorgan involvement.<\/li>\n\n\n\n<li><strong>Eosinophilic Granuloma<\/strong>: Localized lesion(s) confined to bone.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">LANGERHANS CELL HISTIOCYTOSIS (LCH) IN ADULTS<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Definition and Pathophysiology<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Same overall mechanism as in children: LCH is a disorder of <strong>bone marrow\u2013derived Langerhans cells<\/strong> that lose their antigen-presenting ability.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Incidence and Demographics<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Rarity<\/strong>: Affects about <strong>1\u20132 persons per million<\/strong> each year.<\/li>\n\n\n\n<li><strong>Mean Age at Diagnosis<\/strong>: ~32 years.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Clinical Presentation<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Common Symptoms<\/strong> (in approximate order of frequency):\n<ol class=\"wp-block-list\">\n<li><strong>Dermatologic<\/strong> (rash)<\/li>\n\n\n\n<li><strong>Pulmonary<\/strong> (cough, dyspnea, tachypnea)<\/li>\n\n\n\n<li><strong>Bone Pain<\/strong><\/li>\n\n\n\n<li><strong>Diabetes Insipidus (DI)<\/strong> (~25% of adult patients)<\/li>\n\n\n\n<li><strong>Systemic<\/strong> (fever, weight loss)<\/li>\n\n\n\n<li><strong>Lymphadenopathy<\/strong><\/li>\n\n\n\n<li><strong>Ataxia<\/strong><\/li>\n\n\n\n<li><strong>Gingival Hypertrophy<\/strong><\/li>\n<\/ol>\n<\/li>\n\n\n\n<li><strong>Skin Lesions<\/strong>: Papular, pigmented (red, brown), possibly ulcerating in intertriginous areas.<\/li>\n\n\n\n<li><strong>Bone Involvement<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Common sites: Mandible, skull, long bones, pelvis, scapula, vertebral bodies, ribs.<\/li>\n\n\n\n<li>Jaw pain and \u201cfloating teeth\u201d on dental radiographs if the mandible is involved.<\/li>\n\n\n\n<li>Lytic lesions with a beveled edge on radiographs.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Pulmonary LCH<\/strong>:\n<ul class=\"wp-block-list\">\n<li>May present with pneumothorax.<\/li>\n\n\n\n<li>Exacerbated by cigarette smoking.<\/li>\n\n\n\n<li>Imaging: Diffuse honeycomb lung appearance on chest radiographs; CT shows typical nodules and cysts.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Endocrine<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/myendoconsult.com\/learn\/topics\/diabetes-insipidus\/\"  data-wpil-monitor-id=\"78\">Diabetes Insipidus<\/a><\/strong> is irreversible in many adult LCH cases due to infiltrative damage to the hypothalamus and pituitary stalk.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Diagnosis<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Biopsy of Lesion<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Mixed cellular infiltrate with immature clonal Langerhans cells (positive for S100, vimentin, CD1a, antilangerin).<\/li>\n\n\n\n<li>Eosinophils, macrophages, granulocytes, lymphocytes often present.<\/li>\n\n\n\n<li>Multinucleated giant cells (foam cells) may appear with accumulated cholesterol.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Full Laboratory and Imaging Workup<\/strong>:\n<ul class=\"wp-block-list\">\n<li>CBC, liver function tests, coagulation studies, fasting urine\/serum osmolality.<\/li>\n\n\n\n<li>Imaging: Skeletal survey, skull radiographs, chest radiograph, possibly head MRI, chest CT, pulmonary function tests, bone marrow biopsy depending on symptoms.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Prognosis<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Influenced by:\n<ol class=\"wp-block-list\">\n<li><strong>Age of Onset<\/strong> (better if older than 2 years)<\/li>\n\n\n\n<li><strong>Number of Organs Involved<\/strong><\/li>\n\n\n\n<li><strong>Degree of Organ Dysfunction<\/strong> (e.g., hyperbilirubinemia)<\/li>\n<\/ol>\n<\/li>\n\n\n\n<li>An adult with a single bone lesion may have an excellent outlook, whereas an infant with extensive multiorgan disease has a worse prognosis.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Treatment<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Stratification by Prognosis<\/strong>:\n<ul class=\"wp-block-list\">\n<li><strong>Chemotherapeutic Agents<\/strong>: Cladribine (2-chlorodeoxyadenosine), vinblastine, etoposide, methotrexate, 6-mercaptopurine.<\/li>\n\n\n\n<li><strong>Corticosteroids<\/strong>: Topical or systemic.<\/li>\n\n\n\n<li><strong>Radiotherapy<\/strong> (localized) and <strong>Surgical Curettage<\/strong> for solitary bone lesions.<\/li>\n\n\n\n<li><strong>Anticytokine Therapies<\/strong>: Under investigation.<\/li>\n\n\n\n<li><strong>Bone Marrow Transplantation<\/strong>: In refractory cases.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>LANGERHANS CELL HISTIOCYTOSIS (LCH) IN CHILDREN Definition and Pathophysiology Incidence Clinical Presentations Bone Involvement Endocrine Manifestations Lymph Node Involvement Diffuse Multisystem Disease Historical Terminology LANGERHANS CELL HISTIOCYTOSIS (LCH) IN ADULTS Definition and Pathophysiology Incidence and Demographics Clinical Presentation Diagnosis Prognosis Treatment<\/p>\n","protected":false},"featured_media":0,"template":"","oen_topic_chapter":[682],"class_list":["post-4422296","oen_topic","type-oen_topic","status-publish","hentry","oen_topic_chapter-pituitary-gland","post-wrapper","thrv_wrapper"],"_links":{"self":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422296","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic"}],"about":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/types\/oen_topic"}],"version-history":[{"count":3,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422296\/revisions"}],"predecessor-version":[{"id":4422300,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422296\/revisions\/4422300"}],"wp:attachment":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/media?parent=4422296"}],"wp:term":[{"taxonomy":"oen_topic_chapter","embeddable":true,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic_chapter?post=4422296"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}