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.