Nails
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| acroosteolysis | Recurrent ulcers in the fingers & toes. Congenital; autosomal dominant Acquired; workers who handle vinyl chloride |
| age-related nail changes | koilonychia, lamellar dystrophy, longitudinal pigment (blacks), onychodystrophy (10-66%), onychogryphosis, onychomadesis, onychorrhexis, pitting, pressure changes, red spotted lunula, slowed growth, Terry’s nails, thickened plate, thinned plate, trachyonychia |
alcoholism | clubbing, koilonychia, red lunulae, Terry’s nails |
| Aldrich-Mees lines | AKA Mees lines |
| almond nails | Nail shaped like an almond nut; Naegli syndrome, normal variant |
alopecia areata | Beau’s lines, brittle nails, koilonychia, leukonychia punctata, longitudinal ridging, onycholysis, onychomadesis, pits, red nails, spotted lunulae, thickened nails |
angel wing deformity | deformity of nail; lichen planus |
anonychia | absence of all or portion of nail; Clouston syndrome, congenital, lichen planus, nail-patella syndrome |
AZT | melanonychia |
azure lunulae | bluish proximal nail bed; agyria, Wilson’s disease |
bands; longitudinal pigmented | acrodermatitis enteropathica, Addison’s disease, AIDS, amyloid (primary), arsenic, carcinoma of breast, carpal tunnel syndrome, Cushing’s disease, fluorosis, gastrointestinal disease, hemosiderosis, hyperbilirubinemia, hyperthyroidism, hypopituitarism irradiation, Laugier-Hunziger s., malnutrition, melanoma (metastatic), ochronosis, Peutz-Jeghers syndrome, porphyria, pregnancy, syphilis (secondary) |
bands; longitudinal white | Hailey-Hailey disease |
beading | rheumatoid arthritis |
Beau’s lines | transverse depression of nail plate; alopecia areata, b-blockers, cytotoxic drugs, dysmenorrhea, Kawasaki d., MI, nutritional deficiency, post fever, psoriasis |
beta-blockers | Beau’s lines, digital ischemia, leukonychia (apparent), onychomadesis |
| bifid nail | nail-patella syndrome |
blue nails | antimalarials, AZT, 5-flouracil, hematoma, Wilson’s disease |
brachydactyly | pseudohypoparathyroidism |
brachyonychia | AD; greater width than length of nail plate AKA racquet nail |
brittle nails | dehydration, elderly, irritant contact, lichen planus, Marinesco-SjØgren s., nail polish, onychomycosis, psoriasis, retinoids |
brown/black nails | AZT (esp. blacks), antimalarials, Peutz-Jeghers syndrome |
canal | single wide groove from matrix pressure; myxoid cyst |
chevron nail | V-shaped longitudinal ridging in children |
chromonychia | abnormal nail color; external contactant, methemoglobinemia, systemic chemical absorption |
clubbing | cuticle (Lovibond’s) angle greater than 180 degrees due to fibrovascular hyperplasia; acrocyanosis, alcohol, amyloidosis (secondary), angiectasis, arsenic, Ascaris infection, beryllium, biliary cirrhosis, bronchitis, bronchiectasis, cardiopulmonary disease, CHF, chilblains, chronic myelogenous leukemia, Clouston’s syndrome, collagen vascular disease, congenital dysplasia, congenital heart disease, citrullinemia, cretinism, diarrhea (chronic-sprue), cyanotic heart disease, emphysema, endocarditis (subacute bacterial), familial, fibrosarcoma, GI neoplasm, Gottron’s syndrome, Graves’ disease, hepatic cirrhosis, hereditary sclerosing poikiloderma, Hodgkin’s disease, hypertrophic hypervitaminosis A, hypothyroidism (thyroid acropathy), osteoarthropathy, idiopathic, Kaposi’s sarcoma, leprosy, liver disease, lung abscess, lung cyst, lymphoma, Maffucci’s syndrome, mercury, mesoendothelioma, myxedema, myxoid tumor, neutropenia (chronic familial), pachydermoperiostosis, Peutz-Jeghers syndrome, phosphorus, pneumonia, POEMS syndrome, post-thyroidectomy, primary polycythemia, pseudotumor, pulmonary fibrosis, pulmonary neoplasm (<5%), Raynaud’s disease, rheumatic fever, scleroderma, SLE, sprue, syphilis, syringomyelia, tuberculosis, ulcerative colitis |
clubbing-unilateral or unidigital | arterial aneurysm, brachial arteriovenous fistula, erythromelalgia, felon, gout (tophaceous), lymphangitis, median nerve injury, Pancoast’s tumor, sarcoidosis, shoulder subluxation, trauma |
Darier disease (Darier-White disease) | distal V-shaped notch, red longitudinal subungual streaks, wedge-shaped subungual hyperkeratosis, white longitudinal subungual streaks |
discoloration; topical agents that cause nail discoloration | black: phenol sulfate hydroquinone, red wine, silver nitrate blue: cyanide, oxalic acid, silver gray-blue: ammoniated mercury, mercuric chloride (with UV) green: chlorophyll, copper salts orange-brown: anthralin, Arning’s tincture, burnt sugar, chromium salts, chrysarobin, dinitrotoluene, dithranol, formaldehyde, flutaraldehyde, henna, hydroquinone, iodohydroxyquinolene, iron, mepacrine, nicotine, paraquat, pecan, picric acid, potassium permanganate, pyrogallol, resorcin, rivanol, roasted coffee, thermal injury, vioform, walnuts purple: gentian violet red: carbol-fuchin yellow: amphotericin, dinitro-orthocresol, dinubuton, fluorescein, hydrofluoric acid |
drugs | AZT, b-blockers, PUVA, retinoids |
dyschromia | white/red longitudinal streaks; Darier-White disease, SCC in situ proximal nail bed white, absent lunula; Terry’s nail double white translucent bands; Muehrcke’s lines distal brown; Lindsay’s nail |
dysplasia, toenails | popliteal web syndrome |
dystrophy | amyloidosis, Clouston’s syndrome, exfoliative erythroderma, glucagonoma s., KID syndrome, Olmsted’s syndrome, Rabson-Mendenhall syndrome, Rothmund-Thompson syndrome, Sabinas syndrome, trauma, Zinsser-Cole-Engman syndrome |
| dystrophy, 5th digit | Coffin-siris syndrome |
dystrophy, median | habit tic, mucous cyst |
dystrophy, occupational | motor oils, permanent wave solutions, solvents, trauma |
eggshell nails | dull gloss, brittle, easily split nail |
| fissures, longitudinal | nail-patella syndrome |
friable | nail enamel use, onychomycosis (superficial) |
groove, longitudinal | Schopf-Schulz-Passarge syndrome (also see median canaliform dystrophy of Heller) |
groove, oblique | Schopf-Schulz-Passarge syndrome |
groove, transverse | AKA Beau’s line |
growth, decrease rate of nail | acute infection, aging, antimitotoic drugs, cold climate, congestive heart failure, decreased circulation, females, hypothyroidism, paralysis, immobilization, lactation, malnutrition, measles, mumps, nighttime, peripheral neuropathy, pneumonia, smoking, systemic disease, yellow nail syndrome |
growth, increase rate of nail | dominant hand, hyperpituitarism, hyperthyroidism, AV shunt, local repetitive trauma, longer digits, males, onycholysis, periungual inflammation, pregnancy, premenstrual, psoriasis, regeneration, warm climate |
half and half nails | white proximal & brown distal nail (melanin); chronic renal failure, uremia AKA Lindsay’s nails |
| hapalonychia | softened nails due to matrix defect; malnutrition, myxedema, leprosy, Raynaud disease |
hard nails | pachyonychia congenita |
harlequin nail | distal yellow stained nail & proximal clear nail after abrupt smoking cessation |
Heller’s median canaliform dystrophy | split midline nail with fir tree-like appearance at backward angle; myxoid cyst, repeated trauma (picking at cuticle-typically the thumb nail) |
hemionychia | nail-patella syndrome |
Hippocratic nail | onychogryphosis |
hook nail | bowing of nail due to lack of support of the short bony phalanx |
Hutchinson’s sign | pigment leaching into nail fold; melanoma |
hyperkeratosis, subungual | crusted scabies, Darier-White disease, lichen planus, Mal de Meleda, onychomycosis, pachyonychia congenita, pityriasis rubra pilaris, psoriasis, Reiter’s syndrome, Werner syndrome |
hyperpigmentation | acrokeratosis verruciformis of Hopf, Laugier-Hunziger syndrome, panhypopituitarism |
hyperpigmentation, chemotherapeutic agents | aminoglutethimide, bleomycin, busulfan, cisplatin, cyclophosphamide, cytarabine, dacarbazine, dactinomycin, daunorubicin, docetaxel, doxorubicin, etoposide, fluorouracil, hydroxyurea, idarubicin, ifosfamide, melphalan, methotrexate, mitomycin, mitoxantrone, tegafur, vincristine |
ingrown | retinoids |
koilonychia | alkalis & acids, alopecia areata, acanthosis nigricans, acromegaly, alopecia areata, anemia (chronic), Bantis syndrome, cachexia, chondroectodermal dysplasia (Ellis-van Creveld syndrome), coronary artery disease, Darier’s disease, ectodermal dysplasia, familial, focal dermal hypoplasia, frostbite, Gottron’s syndrome, hemochromatosis, hypothyroidism, hypovitaminosis B2 & C, idiopathic, incontinentia pigmenti, iron deficiency, LEOPARD syndrome, lichen planus, Mal de Meleda, malnutrition, monilethrix, nail-patella syndrome, Nezelof’s syndrome, normal children, occupational, onychomycosis, palmar hyperkeratosis, palmoplantar keratoderma, pellagra, petroleum products, Plummer-Vinson syndrome, polycythemia vera, porphyria cutanea tarda, post-gastrectomy, primary amyloid, psoriasis, Raynaud’s disease, renal transplant, scleroderma, sideropenic anemia, steatocystoma multiplex, syphilis, thyrotoxicosis, thermal burns, thioglyoclate contact (hairdressers) AKA spoon nail |
leukonychia | white spots on nail plate due to matrix dysfunction; b-blockers, chilblains, dysmenorrhea, Hodgkin’s disease, idiopathic, leprosy, metastatic carcinoma, nephritis, psoriasis, tuberculosis longitudinal; Darier’s disease punctate; minor trauma total; inherited transverse; systemic disorder |
lichen planus | angel wing deformity, atrophy, onycholysis, onychomadesis, onychorrhexis, pterygium, shedding, subungual hyperkeratosis, subungual hyperpigmentation, thinning |
Lindsey’s nails | white proximal, red/brown distal nail; chronic renal failure AKA half & half nails |
liver disease | brittleness, clubbing, flat nails, striations, watch-glass deformity, white bands, white nails |
Lovibond’s angle | cuticle angle; greater than 180° indicates clubbing (see clubbing) |
lunula, absent | endocrine, collagen vascular reticuloendothelial disease, normal variant |
| lunula, blue | Medications (AZT, busulfan, phenolphthalein, systemic 5-FU), Wilson disease |
lunula, dyschromia | azure; hepatolenticular degeneration (Wilson disease) red; alopecia areata, CHF, CO poisoning, collagen vascular disease white; ischemia yellow; tetracycline |
| lunula, slate blue | argyria |
lunula, red spotted | alopecia areata |
lunula, triangular | nail-patella syndrome (pathognomonic) |
lunula, ulceration | GVH disease |
median canaliform dystrophy of Heller | split midline nail with fir tree-like appearance at backward angle; myxoid cyst, repeated trauma (picking at cuticle-typically the thumb nail) |
Mees’ lines | paired narrow white transverse nail lines; antimony poisoning, arsenic exposure, cachectic state, carbon monoxide poisoning, carcinoid, cardiac insufficiency, childbirth, chemotherapy, crush injury, cryotherapy, endemic typhus, erythema multiforme, fluorosis, fracture, glomerulonephritis, gout, herpes zoster, Hodgkin’s disease, hyperalbuminemia, lead poisoning, leprosy, malaria, measles, menstruation, myocardial infarction, parathyroid insufficiency, pellagra, pneumonia, protein deficiency, psoriasis, renal failure, renal transplant, shock, sickle cell anemia, syphilis, systemic disease, thallium poisoning, tuberculosis, ulcerative proctitis, vitamin B12 deficiency, warm-reacting antibody immunohemolytic anemia, zinc deficiency |
melanonychia | AZT, bleomycin, cyclophosphamide, ketoconazole, melanoma, minocycline, psoralen, PUVA |
melanonychia, fungal | aspergillus, scitolytium, scopulariopsis |
melanonychia, longitudinal multiple | Addison’s disease, AIDS, Cushing’s syndrome, folic acid deficiency, hyperthyroidism, vitamin B12 deficiency |
melanonychia, transverse | cytotoxic drugs |
micronychia | Clouston syndrome, nail-patella syndrome |
Morton’s toe | 2nd toe longer than great toe, may become injured by shoes |
Muehrcke’s nails, lines | paired white parallel transverse bands; hypoalbuminemia (2° to chemotherapy), nephrotic syndrome |
nail plate thickening | chronic trauma, Darier-White disease, lichen planus, onychomycosis, pachyonychia congenita, psoriases, PRP, scabies (crusted) |
nicotine sign | yellow discoloration of distal fingers & fingernails; smokers |
notch, distal | Darier’s disease |
oil drop sign | yellow-brown lesions under nail plate; psoriasis AKA salmon patch |
onychochauxis | thickening, darkening, and irregular surface; diabetes mellitus, HIV, hypogonadism |
onychodystrophy | alopecia areata, psoriasis |
onychogryphosis | brown, thickened spiraled nail; footwear trauma, ichthyoses, impaired circulation, Mal de Meleda, onychomycosis, poor hygiene, psoriasis AKA ram’s horn nails |
onychoheterotopia | ectopic nails |
onycholysis | distal irregular separation of nail plate from nail bed; acrylic nail cement, allergic contact dermatitis, amyloid, anemia, bacteria, Bantu porphyria, bronchiectasis, carcinoma of lung, circulatory disorders, Cronkhite-Canada syndrome, CTCL, dermatitis, diabetes mellitus, drug reaction, eczema, erythropoietic porphyria, erythropoietic protoporphyria, formaldehyde, fungus, Graves’ disease, histiocytosis X, ischemia (peripheral), leprosy, lichen planus, lupus erythematosus, neuritis, panhypopituitarism, pellagra, pemphigus vulgaris, plasticizers, pleural effusion, porphyria, pregnancy, pseudoporphyria of hemodialysis, psoriasis, pustular eruption of pregnancy, Raynaud’s phenomenon, Reiter’s syndrome, scleroderma, Sezary syndrome, SCC, syphilis, thyroid disease, trauma, Vitamin C deficiency, warts, yellow nail syndrome |
onychomadesis | shedding of nail plate; alopecia areata, b-blockers, thrombosis |
onychomycosis | proximal & proximal white superficial; HIV, immunosuppression immunosuppression, hyperhidrosis, diabetes mellitus, aging |
onychomycosis | proximal subungual onychomycosis (HIV); Trichophyton rubrum, T. megninii white superficial onychomycosis; T. mentagrophytes nondermatophytes; Candida, Scopulariopsis brevicaulis, Hendersonula toruloidea (Scytalidium dimidiatum), Aspergillus sydowii |
| onychoptosis | nail plate loss |
onychorrhexis | longitudinal grooves & ridges of nail plate; alopecia areata, lichen planus, normal with aging (mild) |
onychoschizia | metabolic acidosis |
Osler’s toe | onychogryphosis |
paronychia, acute | thickened nails: infection, manicuring, retinoids, trauma |
paronychia, chronic | thickened nails: biting, contactants, dermatitis, infection, psoriasis, sucking |
parrot-beaking | widening onychocorneal band of finger nails; Unna-Thost disease |
periungual infarcts | Wegener’s granulomatosis |
photo-onycholysis | mercaptopurine, PUVA |
pincer (trumpet) nails | footwear pressure, idiopathic, osteoarthritis, psoriasis, subungual exostoses |
pitting | alopecia areata, atopy, basal cell nevus syndrome, chronic paronychia, Darier disease, eczema, fungal infection, lichen nitidus, lichen planus, normal variant, psoriasis, Reiter disease, reticulate acropigmentation of Kimura, rheumatoid arthritis, trauma |
| platyonychia | increased longitudinal curvature of the nail |
pseudo-Hutchinson’s sign | discoloration of matrix in subungual hematoma |
| pseudoleukonychia | whittened nail due to external cause such as onychomycosis |
pseudopyogenic granuloma | retinoids |
psoriasis | grooves, leukonychia, oil drop sign, onychodystrophy, onycholysis, pitting, salmon patch, splinter hemorrhage, spooning, subungual hyperkeratosis |
pterygium | scarring nail bed separation from matrix; dyskeratosis congenita, familial, idiopathic, progressive systemic sclerosis, Raynaud’s disease, Stevens-Johnson syndrome, trauma, vascular insufficiency dorsal; bullous dermatosis, congenital, digital ischemia, LP, radiotherapy, trauma ventral; causalgia, formaldehyde exposure, scleroderma with Raynaud phenomenon, trauma, congenital |
| pterygium inversum unguis | congenital, CTD, formaldehyde in nail cosmeceuticals, trauma, |
Quincke’s pulse | aortic insufficiency |
racquet nail | AD; greater width than length of nail plate AKA brachyonychia |
ram’s horn | onychogryphosis |
rheumatoid d. | atrophy, capillary dilation, proximal erythema |
ridging | CIE, Darier’s disease, lichen planus, normal elderly, peripheral vascular disease, RA |
ridging; longitudinal | acrokeratosis verruciformis of Hopf, panhypopituitarism |
salmon patch | yellow-brown subungual discoloration AKA oil drop sign; psoriasis |
| sandpaper nails | rough, opaque nails; trachyonychia |
splinter hemorrhages | damaged longitudinal vessel of nail bed which exudes blood; dermatologic: alopecia mucinosa, Darier’s disease, eczema, exfoliative dermatitis, keratosis lichenoides chronica, mycosis fungoides, onychomatricoma, pemphigoid, pemphigus, pen-push purpura, psoriasis, pterygium, purpura, polyarteritis nodosa, pityriasis rubra pilaris, porphyria, Raynaud’s disease infectious: bacterial endocarditis, fungi, HIV, onychomycosis, psittacosis, trichinosis medications: drug reaction, methoxsalen, tetracycline miscellaneous: altitude (high), irradiation, normal variants, radial artery puncture, radiodermatitis, trauma, Vitamin C deficiency systemic: amyloid, anemia, antigen-antibody complex disease, antiphospholipid coagulopathy, antiphospholipid syndrome, Behçet’s syndrome, Buerger’s disease, Carney complex, cirrhosis, cryoglobulinemia, cystic fibrosis, diabetes mellitus (10%), dialysis, emboli (arterial), histiocytosis X, Letterer-Siwe disease, leukemia, Osler-Weber-Rendu syndrome, malignancy, mitral stenosis, multiple sclerosis, glomerulonephritis, heart disease, hemochromatosis, hepatitis, hypertension, hypoparathyroidism, illness (chronic), peptic ulcer disease, pulmonary disease, rheumatic fever, rheumatoid arthritis, sarcoid, scurvy, septicemia, SLE, thrombocytopenia, transplant patients, trauma, thyrotoxicosis, vasculitis, Wegener’s granulomatosis |
| splitting, lamellar | LP, prolonged water immersion, retinoids (oral) |
spoon nails | AKA koilonychia |
telangiectasia, periungual | cystic fibrosis |
telangiectasia, posterior nail fold | SLE, systemic sclerosis, dermatomyositis, RA, Raynaud’s syndrome |
tennis toe | Morton’s toe distally injured by sporting events or small shoes |
Terry’s nails | white proximal, distal pink nail (onychodermal band within 0.5-3mm of hyponychium); CHF, diabetes mellitus, liver cirrhosis, normal elderly |
thickening | alopecia areata, congenital ectodermal defects, congenital malalignment of the great toe nails, Darier’s disease, Fischer-Jacobsen-Clouston syndrome, fungal infection, pachyonychia congenita, pityriasis rubra pilaris, psoriasis, trauma |
thinning | alopecia areata |
trachyonychia | rough, dull, brittle nails with frayed edges; alopecia areata, chemical exposure, eczema, idiopathic, lichen planus, psoriasis AKA twenty nail dystrophy |
trumpet nail | AKA pincer nail |
tumors in children | angiokeratoma, digital fibroma, enchondromas of Maffucci’s syndrome, exostoses, Koenen’s (angiofibromas of tuberous sclerosis), hemangiomas of blue rubber bleb nevus or Klippel-Trenaunay-Weber syndrome, incontinentia pigmenti, juvenile xanthogranuloma, osteochondroma, pyogenic granuloma |
turtle back nail | Fabry’s disease |
twenty nail dystrophy | see trachyonychia |
warts, nail region | HPV-1, 2, 4 |
washboard nails | longitudinal depression affecting one or both thumb nails; habitually pushing back cuticle |
watch glass deformity | mild clubbing with slight convex surface of nail; see clubbing |
white | cirrhosis, cryoglobulinemia, Raynaud’s syndrome, selenium deficiency, systemic sclerosis |
yellow | oxalic acid, Pneumocystis infection in AIDS, smoking, Touraine-Solente-Gole syndrome |
yellow nail s. | yellow nails, absent cuticles, inccreased curvatur, diminished lunulae, onycholysis, slowed growth; bronchiectasis, carcinoma of larynx, chronic bronchitis, chronic lymphedema, pulmonary disease, rheumatoid arthritis, sinusitis, thyroid disease |

