Table 2.
Key dermoscopic findings of various cutaneous infections and infestations
| Infection/infestation | Key dermoscopic findings |
|---|---|
| Parasitic infections | |
| Pediculosis capitis | Viable nits: brown, translucent, ovoid eggs with convex extremity firmly attached to the hair shaft |
| Empty nits: translucent with a plane and fissured free ending. | |
| Phthiriasis pubis | Lice adherent to the pubic hair (conical shape of the operculum and the wide fixing sleeve of egg to hair) |
| Scabies | Mite appear as ‘circumflex accent’ like image/“triangle sign” |
| Burrows appear as “S” or “Z” shaped structures (“the delta glider” or “jet with contrail” sign) | |
| Demodex folliculorum | Demodex tails- gelatinous, whitish 1-3 mm creamy thread protruding from skin surface |
| Demodex follicular openings - round, amorphic, grayish/light brown plugs surrounded by an erythematous halo | |
| Cutaneous larva migrans | Translucent brownish structureless areas in a segmental arrangement |
| Tungiasis | Well-defined white halo surrounding a black central punctum. |
| Cutaneous Leishmaniasis | Early lesions: yellow tear-like structures and vessels |
| Later stages: central erosion/ulcerations combined with scales, a white starburst-like pattern, and vascular structures. | |
| Viral infections | |
| Viral warts | Irregular whitish structures, white haloes, or densely packed papillae with central vascular structures |
| Molluscum contagiosum | Central yellowish-white polylobular amorphous structure with surrounding vessels |
| Fungal infections | |
| Tinea corporis | Diffuse erythema, whitish scales, follicular micropustules, brown dots surrounded by a white-yellowish halo, wavy/broken hair. Vellus and morse code hairs. |
| Tinea manuum and tinea pedis | Whitish scales along the palmar & plantar creases |
| Tinea capitis | Comma, corkscrew and zig-zag hair, black dots, short vellus and bar code (morse code) hairs |
| Onychomycosis | Spikes and longitudinal striations of different colors (aurora borealis pattern), pseudoleuconychia and melanonychia |
| Bacterial infections | |
| Lupus vulgaris | Repetitive pattern of orange to golden background pigmentation along with focused linear telangiectasias |
| Tuberculoid leprosy | White areas, yellow globules, linear branching telangiectasia, and decreased white dots as well as hairs |
| Histoid leprosy | Whitish-yellow structureless areas and linear branching vessels |
| Pseudomonas folliculitis | Pale hue, central vellus hair |
| Pitted keratolysis | Heterogeneous architecture at the periphery of the craters |
| Trichobacteriosis | Concretions and nodules along the length of the hair shaft, cottony structures, flame-like pale yellowish adherent nodules, plume sign and skewer sign |