Chapter 117: Histiocytosis

AT-A-GLANCE

• Langerhans cell histiocytosis: Translucent, rose-yellowish, crusted papules or papulovesicles, eczematous lesions, hemorrhagic papules and nodules, petechiae, noduloulcerative mucosal lesions, and nail involvement

• Rosai-Dorfman disease: Lymphadenopathy, cutaneous nodules, and plaques

• Hemophagocytic lymphohistiocytosis: Various cutaneous manifestations such as erythroderma, generalized purpuric macules and papules, and morbilliform eruptions

• Juvenile xanthogranuloma: Solitary as well as multiple (oligolesional) papules or nodules—early lesions show a reddish-brown color; mature lesions have a reddish-yellow appearance

• Benign cephalic histiocytosis: Like juvenile xanthogranuloma; ultrastructural presence of worm-like bodies

• Generalized eruptive histiocytoma of childhood: Widespread, erythematous, essentially symmetrical papules

• Adult xanthogranuloma: Oligolesional, yellow-orange papules that usually appear on the face, neck, and lower arms

• Papular xanthoma: Solitary yellowish papule

• Generalized eruptive histiocytoma: Multiple asymptomatic and symmetrically distributed brownish erythematous papules, particularly involving the axial regions such as the trunk, face, and proximal extremities, frequently flares

• Xanthoma disseminatum: Small, yellow-red to brown papules and nodules that are discrete and are disseminated with a predilection for the flexural and intertriginous areas, as well as for mucous membranes

• Multicentric reticulohistiocytosis: Firm, yellow-brownish papules or nodules that reach a size of several centimeters and progress slowly in size; lesions over the joints of fingers and wrists are typical; often involvement of mucosae and conjunctivae

• Erdheim-Chester disease: Xanthelasma and xanthoma are present in one-sixth of cases; long bone and other extracutaneous involvement

• Necrobiotic xanthogranuloma: Yellowish plaques and nodules that can ulcerate

• Hereditary progressive mucinous histiocytosis: Skin-colored to red-brown papules that usually develop in the first decade on the nose, hands, forearms, and thighs that can later develop into persistent and progressive erythematous papules

• Progressive nodular histiocytosis: Generalized, discrete yellow to red-brown papules and nodules measuring a few centimeters in size with prominent facial involvement

AT-A-GLANCE

• New definition of Langerhans cell histiocytosis (LCH) as rare, inflammatory neoplasia of myeloid-dendritic (mostly clonal) cells with heterogeneous clinical manifestation

• Histopathology:

  • Infiltration of the organs with immature, morphologically rounded myeloid dendritic cells with bean-shaped nuclei; shared characteristics of ...