7.3 Scalp & Hair Disorders
Key Takeaways
- Pityriasis (dandruff) is excessive flaking of the scalp — dry in simple dandruff, oily and waxy in pityriasis steatoides — and is the most common noncontagious scalp complaint
- Tinea capitis (ringworm of the scalp), tinea favosa (favus, with honeycomb crusts), pediculosis capitis (head lice), and scabies are contagious — never service these clients
- Folliculitis is a bacterial infection of a hair follicle; a furuncle is a boil, and a carbuncle is a cluster of boils
- Trichoptilosis is the technical term for split ends; monilethrix is beaded hair; trichorrhexis nodosa is knotted, easily broken hair; fragilitas crinium is brittle hair
- Canities is the technical term for gray hair — congenital (present at birth) or acquired (develops with age); hypertrichosis is abnormal excessive hair growth
Scalp & Hair Disorders
Disorder recognition questions serve one professional purpose: the cosmetologist must decide, from visible signs, whether to service, service with caution, or refuse service and refer. State board exams, including Tennessee's, test this decision constantly. The single most valuable sorting skill is knowing which conditions are contagious — those are never serviced in the salon, both for client safety and for infection-control compliance.
Noncontagious Scalp Disorders
- Pityriasis — the technical term for dandruff: excessive shedding of dead epidermal (skin) cells from the scalp. Ordinary dandruff produces dry, white flakes and itching. Pityriasis steatoides is the oily form, with greasy, waxy, yellowish scales that stick to the scalp, often accompanying seborrhea (excess oil production). Dandruff is not contagious and may be serviced with appropriate scalp treatments, though inflamed cases warrant referral.
- Seborrheic dermatitis — a more severe, inflammatory form of oily scaling with redness and crusting; commonly treated medically.
- Psoriasis — round, dry patches of skin covered with rough, silvery scales, often on the scalp, elbows, and knees. It is not contagious, but it is a chronic medical skin disease: do not treat it in the salon, avoid irritating the patches, and refer to a physician. The phrase "silvery scales" is the exam's signature clue for psoriasis.
Contagious Disorders — Never Service
| Condition | Cause | Identifying Signs | Action |
|---|---|---|---|
| Tinea capitis | Fungus | Ringworm of the scalp: round red patches, broken hairs, itching | Refuse service; refer; disinfect everything |
| Tinea favosa (favus) | Fungus | Dry, sulfur-yellow, honeycomb-shaped crusts with a distinctive odor | Refuse service; refer |
| Pediculosis capitis | Parasite (head lice) | Itching; lice or nits (eggs) glued to hair shafts | Refuse service; highly contagious |
| Scabies | Parasite (itch mite) | Intense itching and burrow lines between fingers and on body folds | Refuse service; contagious |
All tinea conditions are fungal (ringworm) infections — remember that tinea corporis is ringworm of the body and tinea capitis is ringworm of the scalp. Pediculosis capitis is the single most-tested contagious disorder: the exam answer is always to politely decline the service, explain privately, and suggest the client see a pharmacist or physician, then disinfect any tools or capes that made contact.
Bacterial Infections of the Follicle
- Folliculitis — bacterial (usually staphylococcal) infection of a hair follicle, appearing as small red pimples with a hair in the center.
- Furuncle — a boil: a deeper, painful pus-filled infection of one follicle.
- Carbuncle — a cluster of connected furuncles (boils); larger, deeper, and always a medical case.
These are infections: never squeeze, lance, or service over them, and refer the client for medical care.
Hair Shaft Disorders
These conditions affect the strand itself rather than the scalp, and the exam loves the Greek-derived names:
| Disorder | Meaning |
|---|---|
| Canities | Gray hair; congenital canities exists from birth (including albinism), acquired canities develops with age or after illness; ringed canities alternates gray and dark bands |
| Hypertrichosis | Abnormal growth of excessive hair where hair is not normally found |
| Trichoptilosis | Split ends — the hair shaft splits at the distal end; the only cure is cutting |
| Monilethrix | "Beaded" hair: the shaft narrows between bead-like swellings and breaks easily |
| Trichorrhexis nodosa | Knotted hair: dry, brittle knots along the shaft that fray and snap |
| Fragilitas crinium | Brittle hair that breaks or splits at the slightest tension |
Related condition: bromidrosis is foul-smelling perspiration — notice the odor — and when it involves the scalp it calls for cleansing and referral if persistent, not salon diagnosis.
The Service Decision Table
| Condition | Contagious? | Service Decision |
|---|---|---|
| Pityriasis (dandruff) | No | Service with appropriate scalp treatment |
| Psoriasis | No (medical) | Avoid irritation; refer to physician |
| Seborrheic dermatitis | No (medical) | Refer for medical treatment |
| Tinea capitis / favus | Yes (fungal) | Never service; refer; disinfect |
| Pediculosis capitis (lice) | Yes (parasitic) | Never service; refer; disinfect |
| Scabies | Yes (parasitic) | Never service; refer |
| Folliculitis / furuncle / carbuncle | Infection | Do not service the area; refer |
| Trichoptilosis, monilethrix, canities | No | Service normally with gentle care |
Reading the Exam Scenario
Disorder questions on the Tennessee written exam almost always embed two clues: an appearance clue (honeycomb crusts, silvery scales, white specks on the shaft, bead-like swellings) and a scope clue (itching that spreads, pus, sudden patches). Train yourself to extract both before answering. The appearance clue names the disorder — tinea favosa, psoriasis, pediculosis capitis, monilethrix — and the scope clue dictates the response: contagious or infectious means refuse and refer, medical-but-not-contagious means work around it gently or refer, and purely structural means service with care. When two answer choices both name the right condition, the correct one is the answer that pairs it with the safe professional action — never the one that has the cosmetologist treating, lancing, or medicating anything.
The exam pattern is consistent: if the condition spreads person to person (fungal, parasitic) or is an active infection, the correct answer is to refuse or postpone the service and refer — and never to diagnose or treat. If it is a cosmetic or structural issue, service proceeds with adjusted, gentle technique.
A client arrives for a haircut with intense scalp itching, and on inspection the cosmetologist sees small white oval specks firmly attached to individual hair shafts near the scalp. What should the cosmetologist do?
A client's hair snaps easily when combed, and close inspection shows small swellings along each strand with narrow points between them, giving the hair a beaded appearance. What is this condition called?