6.3 Nail Disorders and Diseases: Signs, Symptoms, and Referral

Key Takeaways

  • A manicurist recognizes signs and symptoms and refers; a manicurist does not diagnose or prescribe as a physician.
  • Infectious nail disease (onychomycosis/tinea unguium, paronychia, onychia) is a refuse-and-refer situation, not a longer soak.
  • Pyogenic granuloma and undiagnosed or inflamed nail psoriasis are refer-out conditions, even though psoriasis is not a fungus.
  • Cosmetic or noninfectious disorders such as onychophagy with intact skin, leuconychia, many hangnails without infection, and brittle plates may be serviced with caution.
  • Onycholysis, onychocryptosis, pterygium, eggshell nails, and bruised nails are judged by pain, infection, and broken skin — when in doubt, do not service and refer.
Last updated: September 2026

Disorder, infectious disease, and cosmetic condition

NIC Domain 2 asks you to recognize signs, symptoms, and causes of disorders, diseases, and conditions of the nails. Arkansas still licenses you as a manicurist, not as a physician. Three labels keep you out of trouble:

  • A disorder is an abnormal nail condition. It may or may not be infectious. Onycholysis (plate separating from bed) is a disorder with many possible causes: trauma, product, thyroid disease, psoriasis, or infection underneath.
  • An infectious disease is caused by a pathogen. Onychomycosis and tinea unguium are fungal. Paronychia and onychia are typically bacterial (sometimes mixed). These spread on implements and in water if you ignore infection control.
  • A cosmetic condition is an appearance issue without a contagious disease process — polish stain, a healed bruise growing out, leuconychia white spots from a minor matrix bump, onychophagy (bitten nails) with intact skin.

Your job: see the sign, name it in classroom language, decide service / modify / refuse / refer, and never announce a medical diagnosis as if you were writing a chart in a clinic. Saying “these signs match what our textbook calls onychomycosis; I cannot service this nail; please see a physician” is recognition plus referral. Saying “you have fungus, here is a prescription cream” is practicing medicine.

ADH establishment rules also keep people with communicable disease out of service. You do not need a lab culture to refuse a obviously infected, draining nail. You need the courage to stop.

Infectious and inflammatory emergencies

Onychomycosis is fungal infection of the nail unit. Signs: thickened, brittle, crumbling plate; yellow, white, or brown discoloration; debris under the plate; odor; a plate that looks “chewed” from within. Cause: dermatophyte or other fungi in a moist, sealed space. Service: refuse the affected nails. Refer. Do not file clouds of infected keratin across the salon. Do not trap debris under a tip “to hide it.”

Tinea unguium is ringworm of the nail — the classroom name many items still use for dermatophyte nail infection. Treat it as onychomycosis for service decisions: refuse and refer. It is not “dry toenails.” It is not a stain you buff off.

Paronychia is inflammation of the tissue around the nail (the perionychium), often after a torn hangnail, aggressive cuticle work, or wet work. Signs: redness, heat, swelling, pain, and often pus. Cause: usually bacteria entering a break in living skin. Refuse and refer. Do not “drain it” with a pusher. Do not continue an e-file cuticle clean-up.

Onychia is inflammation of the matrix, often with pus, and it can lead to shedding of the plate. Signs: pain at the base, swelling, discharge, a plate that loosens from the proximal end. Refuse and refer. You cannot disinfect a matrix infection with polish.

Pyogenic granuloma is a refer immediately lesion: a lump of red, raw, easily bleeding tissue growing from the nail bed or fold, often after injury. It is not a polish blob. It is not a hangnail. Do not service. Do not pick. Refer.

Disorders you must still sort into service versus refer

Onycholysis is separation of plate from bed, usually starting at the free edge and moving back. The detached plate looks white or yellow because air and debris sit where the bed used to show pink. Causes: injury, overly aggressive cleaning under the nail, product lifting, psoriasis, thyroid disease, or infection in the space. If the area is clean, painless, and clearly a small mechanical lift, some textbooks allow careful cosmetic work on remaining attached plate without sealing debris into a pocket. If you see odor, debris, discoloration of infection, pain, or you do not know the cause, refer and do not apply enhancements over a hollow.

Onychocryptosis is an ingrown nail. The plate pierces the living lateral fold. Mild, not infected, not deeply embedded: you may file the offending corner without digging into living tissue and refer for medical care if it is more than a cosmetic edge. Red, swollen, draining, or a client who wants you to “cut it out”: refuse and refer. You are not performing nail surgery.

Onychophagy is nail biting. Bitten plates and ragged free edges can still receive a manicure if the skin is intact. Open, raw, bleeding, or infected folds: stop and refer. Do not lecture the client as a substitute for infection control.

Onychorrhexis is split, brittle nails with lengthwise ridges. Often from solvents, injury, or aging keratin. Oil manicures and gentle shaping are the usual cosmetic plan when there is no infection. Sudden severe change plus other body symptoms: refer rather than selling a miracle oil.

Leuconychia is white spots or white streaks. Minor matrix trauma is the usual classroom cause. Can service. Do not call it calcium deficiency as a diagnosis.

Hangnail (agnail) is a split of living skin beside the nail. If small and not infected, nip the dry strip with disinfected nippers — do not rip. If the fold is red, hot, or pus-filled, you are looking at paronychia: refer.

Pterygium after scarring: do not tear. Cosmetic oil will not dissolve scar. Refer when it is medical or you would have to cut living tissue to “clean it.”

Eggshell nails: thin, flexible, white. Gentle service if intact; no aggressive thinning; condition; avoid heavy enhancements that the plate cannot support. Refer if you suspect systemic disease the client has not had evaluated — you still do not diagnose it.

Bruised nail: trapped blood. Gentle service if painless and not infected; refer if painful, swollen, or draining.

Psoriasis of the nail is a skin disease that can pit the plate, leave salmon-colored “oil drop” patches, cause onycholysis, and crumble the plate. It is not tinea unguium, even when it looks crumbly. It is not contagious in the fungal sense, but it is medical. Inflamed, broken, or undiagnosed: do not service; refer. Do not soak a psoriatic hand in a community pedicure tub as if it were ordinary dry skin. Do not tell the client you will “cure psoriasis” with oil.

Service versus refer table

ConditionClassic signsUsual cause familyService or refer
Onychomycosis / tinea unguiumThick, crumbly, discolored, debris, odorFungal infectionRefuse and refer
ParonychiaRed, hot, swollen fold, often pusBacterial infection of surrounding tissueRefuse and refer
OnychiaPainful matrix, pus, possible plate sheddingInfection/inflammation of matrixRefuse and refer
Pyogenic granulomaRed bleeding lump from bed or foldInflammatory lesion after injuryRefuse and refer
Nail psoriasisPitting, salmon patches, crumbling, skin plaques elsewhereMedical skin disease, not fungusRefer; no service on inflamed/broken skin
OnycholysisPlate lifting from free edgeTrauma, product, disease, or infectionRefer if unknown, painful, or infected; do not seal debris
OnychocryptosisIngrown plate in living foldMechanical + fold injuryRefer if infected or embedded; do not cut living tissue
Pterygium (scar)Skin stretched onto plateMatrix/eponychium scarringDo not tear; refer if medical
OnychophagyBitten platesHabitService if skin intact; refer if infected
Onychorrhexis / brittleSplit, dry, ridgedKeratin damage, solvents, agingService; oil manicures; refer if sudden systemic change
LeuconychiaWhite spotsMinor matrix injuryService
Hangnail (agnail)Split living skinDryness, traumaNip if not infected; refer if paronychia
Eggshell nailsThin, flexible, whiteUnder-built plateGentle service if intact
Bruised nailDark patch under plateBlood from traumaGentle service if painless; refer if painful/infected

Exam traps

Trap: treating psoriasis as fungus because both can crumble. Trap: diagnosing tinea unguium out loud and selling a drug. Trap: continuing a manicure through pus because the client “only has 20 minutes.” Trap: cutting an ingrown nail out of the fold. Trap: calling pterygium “cuticle.” Trap: oil manicure as infection prevention — classroom teaching recommends oil for brittle nails, not as an antiseptic.

Scenario: two feet, two decisions

A walk-in wants a polish change. The right great toenail is thick, yellow, and crumbling with debris (textbook tinea unguium / onychomycosis). The left fingernails are short from biting but the skin is closed (onychophagy). The Arkansas manicurist refuses the diseased toenail, does not file the crumbly keratin, explains that a physician must evaluate infection, and may still perform a careful finger manicure on intact skin. That split decision is the whole chapter: recognize, stay in scope, beautify what is healthy, and refer what is disease.

Test Your Knowledge

A client's toenails are thick, yellow, and crumbling, with packed debris and a musty odor. What is the correct first professional action for an Arkansas manicurist?

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D
Test Your Knowledge

After a client ripped a hangnail, the proximal fold is red, hot, swollen, and leaking pus. What is the correct decision?

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C
D
Test Your Knowledge

Several fingernails show pitting, salmon-colored patches, and crumbling, and the client also has scaly plaques on the elbows. What is the best professional response?

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D