Utility of Trichoscopy in Various Types of Alopecia - A Cross-Sectional Study

Background: Alopecia is one of the most common reasons for consulting dermatologists, and the clinical diagnosis can become confusing. In light of the inclination of patients and doctors toward non-invasive diagnosis, along with the vogue of non-invasive diagnostic modalities, trichoscopy has become a promising tool. Objectives: To study various dermoscopic patterns of alopecia. Methods: After obtaining informed consent, this cross-sectional study was conducted among 100 patients with alopecia attending a tertiary health care center. A detailed history and clinical photographs were taken. Relevant investigations were done whenever indicated. Dermoscopy was done using illuco IDS- 1100 with 10x magnification. Statistical analysis used: Data was analyzed using SPSS 22 version software. The chi-square test, Kolmogorov-Smirnov test, and Shapiro-Wilk test was used for assessment with a significant P-value of < 0.05. Kappa statistics were used to assess agreement between the two modalities. Results: Overall, vellus hair (65%) and yellow dots (65%) were the most common findings among all types of alopecia. The most common findings on trichoscopy in androgenetic alopecia were vellus hair (90.48%); in alopecia areata, vellus hair, and exclamation mark hair (86.67% each); in tinea capitis, corkscrew hair, and black dots; and in trichotillomania, splaying of hair. Discoid Lupus erythematosus had absent follicular opening, scaling, and perifollicular pigmentation. Clinical and dermoscopic diagnoses were significantly associated with a kappa agreement of 0.776 (i.e., substantial agreement). Out of 15 cases of difficult-to-diagnose alopecia, further investigations showed that dermoscopic diagnosis was accurate in 7 cases (46.67%). Conclusions: Trichoscopy is a reliable, non-invasive, and faster method of diagnosis in ambiguous cases of alopecia.