Bar code–like hair: Dermoscopic marker of tinea capitis and tinea of the eyebrow

Dermoscopy as a useful supportive tool for the diagnosis of pityriasis amiantacea-like tinea capitis

“…Over the last few years, dermoscopy has been showed to be a useful auxiliary instrument for the recognition of several hair disorders [8–9], particularly dermatophyte infections [3–7]. Indeed, beside nonspecific findings (broken and dystrophic hairs, black dots, scaling, erythema, etc.…”

“…Indeed, beside nonspecific findings (broken and dystrophic hairs, black dots, scaling, erythema, etc. ), tinea capitis may display peculiar dermoscopic features such as “comma” hairs, “corkscrew” hairs, “zigzag” hairs, interrupted (Morse code-like) hairs, “elbow-shaped” hairs and “question mark” hairs [3–7]. Regarding the present instance, even though we observed dermoscopic findings that may be commonly seen in PA, i.e., diffuse white scaling and the characteristic compact white keratotic material adhering to a tuft of hair (asbestos-like scales) [10], dermoscopy turned out to be very helpful in suspecting tinea infection by showing the aforementioned “zigzag” and “question mark” hairs.…”

“…Regarding the present instance, even though we observed dermoscopic findings that may be commonly seen in PA, i.e., diffuse white scaling and the characteristic compact white keratotic material adhering to a tuft of hair (asbestos-like scales) [10], dermoscopy turned out to be very helpful in suspecting tinea infection by showing the aforementioned “zigzag” and “question mark” hairs. In fact, although such features (or similar findings) may be rarely found in other hair disorders (e.g., “zigzag” hairs in trichorrhexis nodosa, alopecia areata and monilethrix, and “question mark” hairs in alopecia areata) [3–7], they are typically not visible in classic PA [10]. …”

“…Dermoscopic examination (performed with DermLite DL3 x10; 3Gen, San Juan Capistrano, CA, USA) revealed diffuse white scales and compact white keratotic material adhering to tufts of hair (asbestos-like scaling) without erythema (Figure 1b); interestingly, several hairs displayed a “question mark” or “zigzag” (hair shaft bent at more than one point) appearance (Figure 1b). As such dermoscopic findings may be found in tinea capitis [3–7], we decided to carry out a direct microscopic examination of 10% KOH preparation of the scales scraped from the scalp, which showed septate branching hyphae. Specimens were also cultured on conventional Sabouraud’s dextrose agar medium, with evidence of Microsporum canis growth after three weeks, thus confirming the diagnosis of tinea capitis.…”

Commentary on dermoscopy in general dermatology

“…curved short hairs produced by Microsporum infection. Other dermoscopic features have been found, such as corkscrew, broken, dystrophic, and bar-code hairs (14)(15)(16)(17). Alopecia areata typically shows black dots (cadaverized hairs) and yellow dots, often correlated with disease severity, and tapering or broken hairs correlated with disease activity; on the other hand the detection of short vellus hairs is a marker of low disease severity and activity (18) (Figure 8).…”