A correlation study between sebum output, acne lesion counts and pore fluorescence density in acne patients

Background: Porphyrins produced by Propionibacterium acnes exhibit an orange-red fluorescence spot on the pilosebaceous pore under UVA light. Based on this characteristic, the recently developed photographic technique, 'fluorescence photography', warrants mention in the context of acne, especially in the assessment of the presence of bacteria and sebum output. Objective: The aim of this study was to assess the relationship between sebum output and acne lesion counts with fluorescent density (% fluorescence area). We discuss the possibility of the use of fluorescence photography as a new tool to evaluate acne and sebum levels. Methods: Total of 39 subjects, 29 males and 10 females, were recruited for this prospective study. To estimate fluorescent density, fluorescent facial images were taken and analyzed with digital fluorescent imaging system and an image analysis program. The sebum output level was measured with a Sebumeter®. Numbers of acne lesions were counted. Also, sebum output and fluorescent images were compared before and after the use of a facial cleanser containing 1% triclosan. Results: Sebum output level was significantly associated with fluorescent density, but not with the number of acne lesions. However, in the group using triclosan containing cleanser, fluorescent density decreased, while sebum level increased. Therefore, fluorescent density seems to be influenced mainly by the density of P. acnes. Conclusion: Fluorescence density correlates with P. acnes mostly followed by sebum output level. Digital fluorescent imaging system is considered as a useful tool to assess sebum excretion as well as colonization of P. acnes.