Protoporphyrin IX fluorescence as potential indicator of psoriasis severity and progression

• Published in: Photodiagnosis and photodynamic therapy Vol. 19; pp. 304 - 307
• Main Authors: Wang, Bo, Xu, Yu-Ting, Zhang, Li, Zheng, Jie, Sroka, Ronald, Wang, Hong-Wei, Wang, Xiu-Li
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2017
• Subjects: Autofluorescence; Diagnosis; Disease Progression; Female; Fluorescence; Hematology, Oncology and Palliative Medicine; Humans; Internal Medicine; Macrospectrometry; Male; Photochemotherapy - methods; Photosensitizing Agents - pharmacology; Protoporphyrin IX; Protoporphyrins - pharmacology; Psoriasis; Psoriasis - diagnosis; Psoriasis - physiopathology; Severity of Illness Index; Diagnosis; Psoriasis; Protoporphyrin IX; Autofluorescence; Macrospectrometry; Disease progression
• ISSN: 1572-1000; 1873-1597; 1873-1597
• DOI: 10.1016/j.pdpdt.2017.05.016

•We showed that only severe psoriatic plaques emit red fluorescence from protoporphyrin IX when illuminated with blue light such as Wood’s lamp.•We identified a significant positive correlation between psoriatic lesion severity and fluorescence intensity.•PpIX-induced red fluorescence can be used as a novel and convenient approach for psoriasis diagnosis and progression evaluation. In psoriatic lesions, fluorescence diagnosis with blue light can detect protoporphyrin IX accumulation, especially after topical 5-aminolaevulinic acid (ALA) application. However, variable fluorescence distributions, interpersonal variations and long incubation time limit its wide application in clinic. This study is aimed to identify a consistent and convenient method to facilitate diagnosis and evaluation of psoriatic lesions. 104 psoriatic lesions from 30 patients were evaluated. Single lesion PSI scoring and fluorescence by macrospectrofluorometry were recorded on each lesion before and after treatment with narrow-band UVB. Punctate red fluorescence, emitted mainly by protoporphyrin IX, is observed in some psoriatic lesions. According to psoriasis severity index, fluorescence-positive lesions are more severe than lesions without fluorescence. We found a significant positive correlation between psoriasis severity and fluorescence intensity from protoporphyrin IX. Protoporphyrin IX-induced red fluorescence can be used as a novel and convenient approach for psoriasis diagnosis and progression evaluation.