Rhododenol (Rhododendrol)-induced leukoderma: an objective way to ascertain normalization of the skin

This study suggests an objective way to follow-up of rhododenol-induced vitiligo by skin absorption spectrum analysis

• A word on Rhododenol (Rhododendrol):
  • Rhododendrol (Rhododenol) is is derived from the white birch tree
  • it inhibits tyrosinase activity and melanin synthesis
  • Vitiligo-like lesions were observed and in march 2014, 14000 cases were reported in Japan alone

In this study the photo-spectrometric character of vitligo-like lesions was done using multi band filtered digital camera:

-skin color absorbance was done between 370nm and 780nm

• in 19 subjects with rhodenol-induced vitligo
• in 9 subjects with vitiligo vulgaris (normal vitiligo)
• in 4 controls

Results:

-the absorbance window was relevant between 420 and 460nm

-maximum absorbance was lower for vitiligo and rhododenol-induced vitiligo when compared with controls

-maximum absorbance was higher for rhododenol-induced vitiligo than vitligo vulgaris

-6 months after stopping rhododenol, absorbance is close to that of healthy skin (and significantly different from baseline) (this is correlated with a clinically visible repigmentation)

(Absorbance for vitiligo vulgaris also increased with steroids, tacrloimus, and when both were combined. This was NOT observed with vitamin D application)

Comment: despite having generated a big health issue because of leucoderma, it seems that the lesions induced are slowly reversible and that the absorbance is comparable to normal skin 6 months after rhododenol is stopped.

Contributors

Dr Christophe Hsu – dermatologist. Geneva, Switzerland

Source of information: p13-24 Inoue M. et al. Comparison of vitiligo vulgarism and rhododenol-induced vitiligo by multi band camera imaging  with multiple linear regression analysis. JSID Annual Meeting (Japanese Society of Investigative Dermatology, 日本研究皮膚科学会) 2014 – Osaka, Japan