On the head it looks like lice but not lice – what is it? - briefly
It is dandruff—tiny, white or yellowish flakes of dead skin that can be mistaken for lice. The condition results from excess scalp shedding, often linked to seborrheic dermatitis or dry skin.
On the head it looks like lice but not lice – what is it? - in detail
The condition often mistaken for head lice consists of tiny, white or grayish particles that cling to hair shafts. These particles are not living insects; they are composed of keratin debris, skin flakes, or fungal elements. Their appearance can be similar to nits, but their composition, attachment method, and treatment differ markedly.
Common causes include:
- Dandruff (seborrheic dermatitis). Flakes detach from the scalp and may adhere to hair, especially near the roots. The flakes are dry, easily brushed away, and are accompanied by mild itching.
- Scalp psoriasis. Thick, silvery scales form on the scalp and can break into smaller fragments that resemble lice eggs. Red, inflamed patches often accompany the scales.
- Tinea capitis (ringworm of the scalp). Fungal infection produces crusty lesions that may shed tiny white particles. Hair loss and a scaly, itchy scalp are typical signs.
- Hair casts (pseudonits). Cylindrical sheathes of keratin encircle hair shafts. They slide freely along the strand and are not attached at the base, distinguishing them from true nits.
- Mite infestations (e.g., Demodex). Microscopic mites and their waste can create a fine, powdery residue that mimics lice debris, though visual identification requires magnification.
Diagnostic steps:
- Examine the scalp under a bright light or magnifying lens. True lice eggs are cemented to the hair near the scalp and have a characteristic oval shape with a curved operculum.
- Perform a “scratch test.” Gently pull a few hairs; if the particles detach easily, they are likely flakes or casts rather than nits.
- Collect a sample of the material for microscopic analysis if fungal infection or mite presence is suspected.
- Assess accompanying symptoms: intense itching, redness, hair loss, or scaling help narrow the cause.
Treatment varies with the underlying condition:
- Dandruff: Anti‑seborrheic shampoos containing zinc pyrithione, ketoconazole, or selenium sulfide.
- Scalp psoriasis: Topical corticosteroids, vitamin D analogues, or coal‑tar preparations.
- Tinea capitis: Systemic antifungal agents such as griseofulvin or terbinafine, combined with medicated shampoos.
- Hair casts: Regular gentle combing with a fine-tooth comb; keratolytic shampoos may reduce formation.
- Mite infestations: Topical acaricides or oral ivermectin, prescribed after confirmation.
Accurate identification prevents unnecessary lice treatments and directs appropriate therapy to resolve the scalp issue.