eczema, generalized eczema) irritant diaper dermatitis (diaper dermatitis, napkin dermatitis) juvenile plantar dermatosis (atopic winter feet, dermatitis plantaris sicca, forefoot dermatitis, moon-boot foot syndrome, sweaty sock dermatitis) molluscum dermatitis nummular dermatitis (discoid eczema, microbial eczema, nummular eczema, nummular neurodermatitis) nutritional deficiency eczema sulzberger–garbe syndrome (oid-oid disease) xerotic eczema (asteatotic eczema, desiccation dermatitis, eczema craquelé, pruritus hiemalis, winter eczema, winter itch) pustular pustular dermatitis is an inflammation of the skin that presents with pustular lesions. eosinophilic pustular folliculitis (ofuji's disease, sterile eosinophilic pustulosis) reactive arthritis subcorneal pustular dermatosis (sneddon–wilkinson disease) seborrheic seborrheic dermatitis is a chronic, superficial, inflammatory disease characterized by scaling on an erythematous base. infantile seborrheic dermatitis leiner's disease pityriasis simplex capillitii (dandruff) seborrheic dermatitis (seborrheic eczema) disturbances of pigmentation disturbances of human pigmentation, either loss or reduction, may be related to loss of melanocytes or the inability of melanocytes to produce melanin or transport melanosomes correctly. albinism–black lock–cell migration disorder of the neurocytes of the gut–deafness syndrome (abcd syndrome) albinism–deafness syndrome (woolf syndrome, ziprkowski–margolis syndrome) alezzandrini syndrome argyria arsenic poisoning vitiligo berlin syndrome pigmentation changes caused by the bioaccumulation of pigments, e.g. canthaxanthin chédiak–higashi syndrome chrysiasis cross–mckusick–breen syndrome (cross syndrome, oculocerebral-hypopigmentation syndrome) dermatopathia pigmentosa reticularis (dermatopathia pigmentosa reticularis hyperkeratotica et mutilans, dermatopathia pigmentosa reticularis hypohidotica et atrophica, dermatopathic pigmentosa reticularis) dyschromatosis symmetrica hereditaria (reticulate acropigmentation of dohi, symmetrical dyschromatosis of the extremities) dyschromatosis universalis hereditaria elejalde syndrome (griscelli syndrome type 1) eruptive hypomelanosis familial progressive hyperpigmentation galli–galli disease griscelli syndrome type 2 (partial albinism with immunodeficiency) griscelli syndrome type 3 hemochromatosis (bronze diabetes) hemosiderin hyperpigmentation hermansky–pudlak syndrome idiopathic guttate hypomelanosis (leukopathia symmetrica progressiva) iron metallic discoloration klein–waardenburg syndrome lead poisoning leukoderma melanoma-associated leukoderma melasma (chloasma faciei, mask of pregnancy) mukamel syndrome necklace of venus nevus anemicus nevus anemicus nevus depigmentosus (nevus achromicus) ocular albinism oculocutaneous albinism pallister–killian syndrome periorbital hyperpigmentation photoleukomelanodermatitis of kobori phylloid hypomelanosis piebaldism pigmentatio reticularis faciei et colli pityriasis alba poikiloderma of civatte poikiloderma vasculare atrophicans postinflammatory hyperpigmentation (postinflammatory hypermelanosis) postinflammatory hypopigmentation progressive macular hypomelanosis quadrichrome vitiligo reticular pigmented anomaly of the flexures (dark dot disease, dowling–degos' disease) reticulate acropigmentation of kitamura revesz syndrome riehl melanosis scratch dermatitis (flagellate pigmentation from bleomycin) segmental vitiligo shah–waardenburg syndrome shiitake mushroom dermatitis (flagellate mushroom dermatitis, mushroom worker's disease, shiitake-induced toxicoderma) tar melanosis (melanodermatitis toxica lichenoides) tietz syndrome titanium metallic discoloration transient neonatal pustular melanosis (transient neonatal pustulosis, lentigines neonatorum) trichrome vitiligo vagabond's leukomelanoderma vasospastic macule vitiligo vitiligo ponctué vogt–koyanagi–harada syndrome waardenburg syndrome wende–bauckus syndrome (pegum syndrome) woronoff's ring x-linked reticulate pigmentary disorder (familial cutaneous amyloidosis, partington amyloidosis, partington cutaneous amyloidosis, partington syndrome type ii, reticulate pigmentary disorder, x-linked reticulate pigmentary disorder with systemic manifestations) yemenite deaf-blind hypopigmentation syndrome drug eruptions drug eruptions are adverse drug reactions that present with cutaneous manifestations. acrodynia (calomel disease, erythredemic polyneuropathy, pink disease) acute generalized exanthematous pustulosis (pustular drug eruption, toxic pustuloderma) acute generalized exanthematous pustulosis adverse reaction to biologic agents adverse reaction to cytokines allopurinol hypersensitivity syndrome anticoagulant-induced skin necrosis anticonvulsant hypersensitivity syndrome bromoderma bullous drug reaction (bullous drug eruption, generalized bullous fixed drug eruption, multilocular bullous fixed drug eruption) chemotherapy-induced acral erythema (palmoplantar erythrodysesthesia syndrome) chemotherapy-induced hyperpigmentation drug-induced acne drug-induced angioedema drug-related gingival hyperplasia drug-induced lichenoid reaction (drug-induced lichen planus, lichenoid drug eruption) drug-induced lupus erythematosus drug-induced nail changes drug-induced pigmentation drug-induced urticaria drug reaction with eosinophilia and systemic symptoms erythema multiforme major (erythema multiforme minor–erythema multiforme von hebra) exudative hyponychial dermatitis fixed drug reaction halogenoderma heparin necrosis hiv disease-related drug reaction hydroxyurea dermopathy injection site reaction iododerma leukotriene receptor antagonist-associated churg–strauss syndrome linear iga bullous dermatosis (linear iga dermatosis) photosensitive drug reaction red man syndrome severe cutaneous adverse reactions (includes dress syndrome, steven johnson syndrome, toxic epidermal necrolysis, stevens-johnson/toxic epidermal necrolysis overlap syndrome, and acute generalized exanthematous pustulosis) scleroderma-like reaction to taxanes serum sickness-like reaction steroid acne steroid folliculitis stevens–johnson syndrome sulfonamide hypersensitivity syndrome texier's disease toxic epidermal necrolysis (lyell's syndrome) urticarial erythema multiforme vitamin k reaction warfarin necrosis endocrine-related endocrine conditions often present with cutaneous findings as the skin interacts with the endocrine system in many ways. acanthosis nigricans associated with malignancy (acanthosis nigricans type i) acanthosis nigricans associated with obesity, insulin-resistant states, and endocrinopathy (acanthosis nigricans type iii) acral acanthosis nigricans (acral acanthotic anomaly) acral dry gangrene acral dry gangrene acromegaly addison's disease adrenal adenoma adrenal carcinoma adrenal hyperplasia alopecia–nail dystrophy–ophthalmic complications–thyroid dysfunction–hypohidrosis–ephelides and enteropathy–respiratory tract infections syndrome (another syndrome) arrhenoblastoma cretinism cushing's syndrome acanthosis nigricans associated with obesity, insulin-resistant states, and endocrinopathy excess ovarian androgen release syndrome (ovarian saha syndrome) familial acanthosis nigricans (acanthosis nigricans type ii) growth hormone deficiency hyperandrogenism–insulin resistance–acanthosis nigricans syndrome (hair-an syndrome) hyperparathyroidism hyperprolactinemic saha syndrome hyperthyroidism hypoparathyroidism hypothyroidism leydig cell tumor multiple endocrine neoplasia type 1 (wermer syndrome) multiple endocrine neoplasia type 2 (multiple endocrine neoplasia type 2a, pheochromocytoma and amyloid-producing medullary thyroid carcinoma, ptc syndrome, sipple syndrome) multiple endocrine neoplasia type 3 (mucosal neuromata with endocrine tumors, multiple endocrine neoplasia type 2b, multiple mucosal neuroma syndrome, wagenmann–froboese syndrome) myxedema panhypopituitarism persistent adrenarche syndrome (adrenal saha syndrome) polycystic ovarian syndrome seborrhoea–acne–hirsutism–alopecia (saha syndrome) thyroid acropachy eosinophilic eosinophilic cutaneous conditions encompass a wide variety of diseases that are characterized histologically by the presence of eosinophils in the inflammatory infiltrate, or evidence of eosinophil degranulation. angiolymphoid hyperplasia with eosinophilia (epithelioid hemangioma, histiocytoid hemangioma, inflammatory angiomatous nodule, inflammatory arteriovenous hemangioma, intravenous atypical vascular proliferation, papular angioplasia, pseudopyogenic granuloma) annular erythema of infancy arthropod assault eosinophilic cellulitis (wells' syndrome) eosinophilic fasciitis (shulman's syndrome) eosinophilic granuloma eosinophilic granulomatosis with polyangiitis eosinophilic pustular folliculitis of infancy (eosinophilic pustular folliculitis in infancy, infantile eosinophilic pustular folliculitis, neonatal eosinophilic pustular folliculitis) eosinophilic ulcer of the oral mucosa (eosinophilic ulcer of the tongue, riga–fede disease, traumatic eosinophilic granuloma) eosinophilic ulcer of the oral mucosa eosinophilic vasculitis erythema toxicum neonatorum (erythema toxicum, toxic erythema of the newborn) granuloma faciale hypereosinophilia hypereosinophilic syndrome incontinentia pigmenti (bloch–siemens syndrome, bloch–sulzberger disease, bloch–sulzberger syndrome) itchy red bump disease (papular dermatitis) juvenile xanthogranuloma kimura's disease nodules–eosinophilia–rheumatism–dermatitis–swelling syndrome pachydermatous eosinophilic dermatitis papular eruption of blacks papuloerythroderma of ofuji pruritic papular eruption of hiv disease epidermal nevi, neoplasms, and cysts epidermal nevi, neoplasms, and cysts are skin lesions that develop from the epidermal layer of the skin. aberrant basal cell carcinoma acanthoma fissuratum (granuloma fissuratum, spectacle frame acanthoma) acrospiroma (clear cell hidradenoma, dermal duct tumor, hidroacanthoma simplex, nodular hidradenoma, poroma) actinic keratosis (senile keratosis, solar keratosis) adenoid squamous cell carcinoma (pseudoglandular squamous cell carcinoma) aggressive digital papillary adenocarcinoma (digital papillary adenocarcinoma, papillary adenoma) basal cell carcinoma apocrine gland carcinoma apocrine nevus arsenical keratosis atrophic actinic keratosis balanitis plasmacellularis (balanoposthitis chronica circumscripta plasmacellularis, balanitis circumscripta plasmacellularis, plasma cell balanitis, plasma cell vulvitis, vulvitis circumscripta plasmacellularis, zoon's balanitis, zoon's erythroplasia, zoon's vulvitis) basal cell carcinoma basaloid follicular hamartoma basaloid squamous cell carcinoma birt–hogg–dubé syndrome bowen's disease (squamous cell carcinoma in situ) brooke–fordyce syndrome ceruminoma cicatricial basal cell carcinoma (morpheaform basal cell carcinoma, morphoeic basal cell carcinoma) ciliated cyst of the vulva (cutaneous müllerian cyst, paramesonephric mucinous cyst of the vulva) clear cell acanthoma (acanthome cellules claires of degos and civatte, degos acanthoma, pale cell acanthoma) clear cell squamous cell carcinoma (clear cell carcinoma of the skin) chronic scar keratosis (chronic cicatrix keratosis) clonal seborrheic keratosis common seborrheic keratosis (basal cell papilloma, solid seborrheic keratosis) cowden syndrome (cowden's disease, multiple hamartoma syndrome) cutaneous ciliated cyst cutaneous columnar cyst cutaneous horn (cornu cutaneum) cystic basal cell carcinoma dermal eccrine cylindroma (cylindroma) dermatosis papulosa nigra desmoplastic trichoepithelioma dilated pore (dilated pore of winer) bowen's disease eccrine carcinoma (syringoid carcinoma) eccrine nevus epidermal cyst (epidermal inclusion cyst, epidermoid cyst, infundibular cyst, keratin cyst) epidermal nevus syndrome (feuerstein and mims syndrome, solomon's syndrome) epidermolytic acanthoma epithelioma cuniculatum (ackerman tumor, carcinoma cuniculatum) eruptive vellus hair cyst erythroplasia of queyrat extramammary paget's disease fibroepithelioma fibroepithelioma of pinkus fibrofolliculoma follicular hybrid cyst (hybrid cyst) folliculosebaceous-apocrine hamartoma (follicular-apocrine hamartoma) folliculosebaceous cystic hamartoma generalized eruptive keratoacanthoma (generalized eruptive keratoacanthoma of grzybowski) giant solitary trichoepithelioma hidradenoma hidradenoma hidradenocarcinoma hidrocystoma (cystadenoma, moll's gland cyst, sudoriferous cyst) hydrocarbon keratosis (pitch keratosis, tar keratosis, tar wart) hyperkeratosis lenticularis perstans (flegel's disease) hyperkeratosis of the nipple and areola hyperkeratotic actinic keratosis ichthyosis hystrix (ichthyosis hystrix gravior type lambert, porcupine man, systematized verrucous nevus) ichthyosis hystrix of curth–macklin infiltrative basal cell carcinoma inflammatory linear verrucous epidermal nevus inverted follicular keratosis irritated seborrheic keratosis (basosquamous cell acanthoma, inflamed seborrheic keratosis) isthmicoma (infundibuloma, tumor of the follicular infundibulum) juvenile myelomonocytic leukemia keratin implantation cyst keratoacanthoma keratoacanthoma centrifugum marginatum large cell acanthoma lichenoid actinic keratosis lichenoid keratosis (benign lichenoid keratosis, lichen planus-like keratosis, solitary lichen planus, solitary lichenoid keratosis) linear verrucous epidermal nevus (linear epidermal nevus, verrucous epidermal nevus) malignant acrospiroma (spiradenocarcinoma) malignant mixed tumor (malignant chondroid syringoma) malignant trichilemmal cyst mantleoma marjolin's ulcer melanoacanthoma (pigmented seborrheic keratosis) merkel cell carcinoma (cutaneous apudoma, primary neuroendocrine carcinoma of the skin, primary small cell carcinoma of the skin, trabecular carcinoma of the skin) microcystic adnexal carcinoma (sclerosing sweat duct carcinoma) micronodular basal cell carcinoma milia en plaque milium milium mixed tumor (chondroid syringoma) mucinous carcinoma mucinous nevus (nevus mucinosus) muir–torre syndrome multiple familial trichoepithelioma (brooke–spiegler syndrome, epithelioma adenoides cysticum) multiple keratoacanthomas (ferguson–smith syndrome, ferguson-smith type of multiple self-healing keratoacanthomas, multiple keratoacanthomas of the ferguson–smith type) multiple minute digitate hyperkeratosis (digitate keratoses, disseminated spiked hyperkeratosis, familial disseminated piliform hyperkeratosis, minute aggregate keratosis) nevoid basal cell carcinoma syndrome (basal cell nevus syndrome, gorlin syndrome, gorlin–goltz syndrome) nevus comedonicus (comedo nevus) nevus comedonicus syndrome nevus sebaceous (nevus sebaceous of jadassohn, organoid nevus) nevus unius lateris nodular basal cell carcinoma (classic basal cell carcinoma) paget's disease of the breast papillary eccrine adenoma (tubular apocrine adenoma) papillary hidradenoma (hidradenoma papilliferum) papillomatosis cutis carcinoides (gottron's carcinoid papillomatosis, papillomatosis cutis carcinoides of gottron–eisenlohr) patch blue nevus (acquired dermal melanocytosis, dermal melanocyte hamartoma) perifollicular fibroma phakomatosis pigmentokeratotica pigmented actinic keratosis pigmented basal cell carcinoma pigmented hairy epidermal nevus syndrome pilar sheath acanthoma pilonidal sinus (barber's interdigital pilonidal sinus, pilonidal cyst, pilonidal disease) porocarcinoma (malignant poroma, eccrine porocarcinoma) polypoid basal cell carcinoma pore-like basal cell carcinoma primary cutaneous adenoid cystic carcinoma proliferating epidermoid cyst (proliferating epithelial cyst) proliferating trichilemmal cyst (pilar tumor, proliferating follicular cystic neoplasm, proliferating pilar tumor, proliferating trichilemmal tumor) pseudocyst of the auricle (auricular endochondrial pseudocyst, cystic chondromalacia, endochondral pseudocyst, intracartilaginous cyst) pseudoepitheliomatous keratotic and micaceous balanitis puva keratosis rasmussen syndrome reactional keratosis reticulated seborrheic keratosis (adenoid seborrheic keratosis) rodent ulcer (jacobi ulcer) schimmelpenning syndrome (schimmelpenning–feuerstein–mims syndrome) sebaceoma (sebaceous epithelioma) sebaceous adenoma sebaceous carcinoma sebaceous hyperplasia sebaceous nevus syndrome seboacanthoma seborrheic keratosis (seborrheic verruca, senile wart) seborrheic keratosis with squamous atypia signet-ring cell squamous cell carcinoma solitary keratoacanthoma (subungual keratoacanthoma) solitary trichoepithelioma spindle cell squamous cell carcinoma (spindle cell carcinoma) spiradenoma squamous cell carcinoma squamous cell carcinoma steatocystoma multiplex (epidermal polycystic disease, sebocystomatosis) steatocystoma simplex (simple sebaceous duct cyst, solitary steatocystoma) stucco keratosis (digitate seborrheic keratosis, hyperkeratotic seborrheic keratosis, keratosis alba, serrated seborrheic keratosis, verrucous seborrheic keratosis) superficial basal cell carcinoma (superficial multicentric basal cell carcinoma) syringadenoma papilliferum (syringocystadenoma papilliferum) syringofibroadenoma (acrosyringeal nevus of weedon and lewis) syringoma systematized epidermal nevus thermal keratosis trichilemmal carcinoma trichilemmal cyst (isthmus-catagen cyst, pilar cyst) trichilemmoma trichoadenoma (trichoadenoma of nikolowski) trichoblastoma trichoblastic fibroma trichodiscoma trichofolliculoma unilateral palmoplantar verrucous nevus urethral caruncle verrucous carcinoma verrucous cyst (cystic papilloma) viral keratosis warty dyskeratoma (isolated dyskeratosis follicularis) waxy keratosis of childhood (kerinokeratosis papulosa) zoon's vulvitis zosteriform speckled lentiginous nevus erythemas erythema migrans erythemas are reactive skin conditions in which there is blanchable redness. erythema annulare centrifugum (deep gyrate erythema, erythema perstans, palpable migrating erythema, superficial gyrate erythema) erythema gyratum repens (gammel's disease) erythema migrans (erythema chronicum migrans) erythema multiforme erythema multiforme minor (herpes simplex-associated erythema multiforme) erythema palmare generalized erythema necrolytic acral erythema necrolytic migratory erythema (glucagonoma syndrome) genodermatoses genodermatoses are inherited genetic skin conditions often grouped into three categories: chromosomal, single gene, and polygenetic. 18q deletion syndrome acrodermatitis enteropathica acrogeria (gottron syndrome) acrokeratosis verruciformis (acrokeratosis verruciformis of hopf) adams–oliver syndrome adducted thumbs syndrome albright's hereditary osteodystrophy angelman syndrome apert syndrome (acrocephalosyndactyly) arthrogryposis–renal dysfunction–cholestasis syndrome ataxia telangiectasia (louis–bar syndrome) atrichia with papular lesions (papular atrichia) atrophodermia vermiculata (acne vermoulante, acne vermoulanti, atrophoderma reticulata symmetrica faciei, atrophoderma reticulatum, atrophoderma vermiculata, atrophoderma vermiculatum, atrophodermia reticulata symmetrica faciei, atrophodermia ulerythematosa, atrophodermie vermiculée des joues avec kératoses folliculaires, folliculitis ulerythema reticulata, folliculitis ulerythematous reticulata, folliculitis ulerythemosa, honeycomb atrophy, ulerythema acneforme, ulerythema acneiforme) autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy syndrome bart syndrome bazex–dupré–christol syndrome (bazex syndrome, follicular atrophoderma and basal cell carcinomas) beare–stevenson cutis gyrata syndrome bloom syndrome (bloom–torre–machacek syndrome) blue