A recent multicentric retrospective observational study found that ultraviolet-induced fluorescence dermoscopy significantly enhances the differentiation between scarring and nonscarring alopecias compared with polarized dermoscopy, particularly in fair-skinned patients.
Published in Dermatology and Therapy, researchers led by Noemi Plozner and Enzo Errichetti from the University of Udine, Italy, analyzed 84 patients (43 with nonscarring alopecia and 41 with scarring alopecia) across five international dermatology centers. Of these patients, 45 had phototypes I-III (24 with nonscarring, 21 with scarring), and 39 had phototypes IV-VI (19 with nonscarring, 20 with scarring).
UVF-dermoscopy proved superior in detecting key diagnostic markers for alopecia classification. Follicular ostia were more frequently identified in nonscarring alopecias using UVF-dermoscopy (83.7% vs. 34.9%; p < 0.01), while bright white areas were more evident in scarring alopecias when comparing UVF-dermoscopy with polarized dermoscopy assessment (70.7% vs. 30.1%; p = 0.01). Under UVF-dermoscopy, follicular openings in balding regions appeared as either red or blue fluorescent follicular dots, attributed to the presence of bacterial porphyrins or follicular hyperkeratosis, respectively.
Skin tone influenced detection accuracy. In dark skin (phototypes IV-VI), only follicular ostia detection was significantly improved with UVF-dermoscopy (particularly with diffuse distribution, 57.9% vs. 10.5%, p < 0.01), while bright white areas showed no significant difference between the two dermoscopic settings. However, in fair skin, UVF-dermoscopy excelled at detecting both markers, with bright white areas benefiting from the higher contrast created by UV-light reflection of fibrotic tissue.
Interobserver agreement, measured by Cohen's kappa coefficient, was significantly higher for UVF-dermoscopy (0.83, "almost perfect") than for polarized dermoscopy (0.57, "moderate"), indicating greater reproducibility.
The study employed the Dermlite DL5 handheld dermatoscope across all centers to ensure standardized assessment and consistent high-resolution imaging.
"UVF-dermoscopy may be a valuable and reliable complementary tool in differentiating scarring and nonscarring alopecias, especially in light phototypes," concluded the researchers in their study.
While these findings suggest UVF-dermoscopy could refine differential diagnosis protocols for alopecia, further research is needed to validate its effectiveness across broader skin tone variations and clinical settings. The authors noted limitations including the retrospective design and lack of dermoscopic-pathological correlation analysis.
Full disclosures are available in the study.
