Measuring acne using Coproporphyrin III, Protoporphyrin IX, and lesion-specific inflammation: an exploratory study

Abstract

Propionibacterium acnes: (P. acnes) produce Porphyrins; however, fluorescence measurement of Porphyrins from Ultraviolet-A (UVA) images has failed to establish a correlation. Acne clinical research and imaging has ignored the spectral excitation-emission characteristics and the exact pattern of the Porphyrins synthesized by P. acnes. In this exploratory study, for the first time, the possible relationships of Coproporphyrin III (CpIII) and Protoporphyrin IX (PpIX) fluorescence as well as acne lesion-specific inflammation measurements with clinical signs of acne are investigated. Furthermore, the sensitivity of these measurements in tracking and differentiating the known treatment effects of Benzoyl Peroxide (BPO) 5%, and combination of Clindamycin + BPO are also evaluated. Comedonal and papulopustular lesions identified by investigators during a live assessment of 24 mild-to-severe acne subjects were compared with fluorescence and inflammation measurements obtained from analysis of VISIA®-CR images. CpIII fluorescence spots showed a strong correlation (r = 0.69–0.83), while PpIX fluorescence spots showed a weak correlation (r = 0.19–0.27) with the investigators’ comedonal lesion counts. A strong correlation was also observed between the investigators’ papulopustular lesion counts and acne lesion-specific inflammation (r = 0.76). Our results suggest that CpIII fluorescence and acne lesion-specific-inflammation measurement can provide objective indication of comedonal and papulopustular acne severity, respectively. Furthermore, these measurements may be more sensitive and specific in evaluating treatment effects and early signs of acne lesion progression compared to investigators’ lesion counts.

Analysis of segmentation methods for acne vulgaris images. Proposal of a new methodology applied to fluorescence images

“…One of the characteristics of acne is the colonization of hair follicles by bacteria Propionibacterium acnes (P. acnes) (Williams et al, 2012;Zouboulis, 2014). Several studies (Patwardhan et al, 2017;Xu et al, 2018) have shown that substances secreted by P. acnes called porphyrins are the cause of acne lesions fluorescence. Porphyrins absorbe ultraviolet (UV) light and emit red fluorescence in response (Borelli et al, 2006;Youn, Kim, Lee, Kim, & Park, 2009).…”

High bacterial colonization and lipase activity in microcomedones

“…[11,12] Indeed, a large number of molecules have been developed to prevent comedogenicity. [13,14] In vivo fluorescence imaging has also been widely employed for acne skin visualization because P acnes produces porphyrins, a family of pro-inflammatory metabolites [15,16] which exhibits a strong fluorescence under A-light ultraviolet (UVA) excitation. [17][18][19] Recently Xu et al confirmed through a systematic analysis that the skin red autofluorescence comes from P acnes porphyrin and that pure sebum present any red autofluorescence.…”

“…Patwardhan et al pointed out that the porphyrin most produced by P acnes, Coproporphyrin III, presents a fluorescence emission between 570 and 630 nm. [15] However, many questions remain open, especially is P acnes colonization in the pilosebaceous unit starting as soon as microcomedone stage? And is it associated with a clear bacterial metabolism?…”

Stratum corneum or stratum ecologica?

“…Look around the world, and with changes in latitude, altitude, water levels, sunlight intensity, it all has an impact on the species that grow and thrive there. On our faces, fluorescence photography can show the location of bacteria on acne prone skin, and can even differentiate species based on how the porphyrins they produce fluoresce [4]. Pores on the face which are next to one another, only fractions of a mm apart, can have different bacterial populations.…”