trichoscopic findings in noncicatricial alopecia and correlations with disease activity, severity and clinical subtype

Scalp dermatoscopy termed as trichoscopy is a new noninvasive method for diagnosis of hair loss. It uses videodermoscopy (or dermoscopy) to visualize and measure scalp hair, eyebrows and eyelashes at high magnification. Structures which may be visualized by trichoscopy include hair shafts, hair follicle openings, the perifollicular epidermis and cutaneous microvasculature. Trichoscopy allows distinguishing between terminal hairs and vellus hairs and this method enables visualization of micro-exclamation mark hairs which may be 1 to 2 mm or less in length. Consequently, trichoscopy helps distinguishing cicatricial alopecia from noncicatricial alopecia. Lately trichoscopic findings allowed an algorithmic approach in hair loss.This study is designed to evaluate the correlation between trichoscopic findings and disease severity, activity and clinical subtype in noncicatricial alopecia. Multipl images obtained with videodermoscopy (MoleMax® III) from 305 patients with various scalp and hair disorders who referred to Dokuz Eylül University School of Medicine Department of Dermatology out-patient clinic with the complaint of hair loss and 108 unaffected control subjects were reviewed for distinguishing trichoscopic features. Conditions evaluated included psoriasis (n: 31), seborrheic dermatitis (n :112), alopecia areata (n: 39), female androgenetic alopecia (n: 138), male androgenetic alopecia (n: 63), female androgenetic alopecia of male pattern (n: 5), telogen effluvium (n: 22) and trichotillomania (n: 4). Disease severity and activity were estimated for AA and AGA. Trichoscopic findings of the patients were compared by using Mann-Whitney U test, logistic regression analysis, Chi square analysis and ratio test.There was no statistically significant difference between disease severity and trichoscopic findings in FAGAM patients. White scales, glomerular vessels and arborizing red lines were detected to be significantly more frequent in FAGA patients with mild and/or early disease while brown dots were significantly more frequent in FAGA patients in severe and/or latestages. Perifollicular discoloration (hyperpigmentation) and increased number of hairs in one pilosebaceous unit were significant trichoscopic findings in MAGA patients with mild and/or early disease while patients with severe and/or late stages of MAGA revealed honeycomb-type hyperpigmentation pattern, white and brown dots.The incidence of each dermoscopic finding in MAGA and FAGA were compared using the ratio test and perifollicular hyperpigmentation in FAGA and yellow, brown and white dots in MAGA were found to be significantly common. When the same estimation were calculated between trichoscopic findings of psoriasis and seborrheic dermatitis, red globule and dots, atypical red vessels, structureless red areas, signet ring vessels and white-grey veil appearance in proximal part of hair were detected to be more frequent psoriasis and twisted red loops and comma vessels in seborrheic dermatitis.New trichoscopic findings detected for the first time in AA patients in our study included clustered white dots, increased number of hairs in one pilosebaceous unit, black dotted pigmentation, white-grey veil appearance in proximal part of hair and arborizing red lines. Honeycomb-type hyperpigmentation pattern, clustered white dots and black dotted pigmentation correlated with the severity of AA and exclamation mark hairs correlated with AA activity while exclamation mark hairs correlated negatively with the severity of AA and atypical red vessels and white dots correlated negatively with disease activity. The risk for severe disease for AA were 36.2 times higher for honeycomb-type hyperpigmentation, seven times for white and clustered white dots, 17 times for black dotted pigmentation and 4.6 times less for exclamation-mark hair.There was no correlation between skin type with white dots, perifollicular hyperpigmentation and honeycomb-type hyperpigmentation.When trichoscopic findings were compared within the control group, perifollicular hyperpigmentation and increased number of hairs in one pilosebaceous unit were significantly more frequent in patients under age 25 then patients over age 50.Accordingly six new distinguishing trichoscopic structures including increased number of hairs in one pilosebaceous unit, white-grey veil appearance in proximal part of hair, brown dots, dotted black dots, clustered white dots and signet ring vessels were defined in our study which were not mentioned before in other dermatoscopic studies in alopecia patients. In addition, correlation between trichoscopic findings and disease severity in AGA are described for the first time in this report.