Characterizing UV-induced fluorescence dermatoscopy (UVFD) of warts and molluscum contagiosum and its utility for expert and novice dermatoscopists

Ultraviolet-induced fluorescence dermatoscopy (UVFD), an emerging dermatoscopy mode, has proven utility in guiding the diagnosis of skin conditions by identifying unique patterns. The primary aim of this study was to describe the dermatoscopic findings of warts and molluscum contagiosum (MC) using UVFD. The secondary objective was to determine the perceived diagnostic confidence of this technique across different levels of experience. We conducted a descriptive and observational study at a Tertiary Care Center. 30 warts and 55 MCs were included. Polarized dermoscopy and UVFD structures were evaluated. Diagnostic confidence (scored from 1 to 6) under UVFD was assessed for both conditions and tested across different levels of dermatoscopy expertise using an online-survey. Under UVFD, 96.7% of the warts had bluish-white fluorescence, while 43.6% of MC were hyporeflective and 100% had yellowish or bluish fluorescent rounded/oval structures. There was a statistically significant increase in the mean diagnostic confidence score when using UVFD compared to polarized light for the assessment of warts (5.52 ± 0.45 vs. 4.89 ± 0.75; p = 0.005) and MC (5.41 ± 0.43 vs. 5.05 ± 0.42; p = 0.012) in the ‘non-expert group’. In the ‘expert group’ this difference in confidence was not significant. UVFD revealed distinct fluorescence patterns in warts and MCs and was associated with higher perceived diagnostic confidence among non-experts. Limitations include the descriptive design, small sample size, and lesion heterogeneity. This study describes the potential of UVFD as a complementary tool to traditional dermatoscopy for identification of warts and MC. UVFD could be especially relevant among less experienced dermatoscopists.