The Clinical Usefulness of Portable Digital Skin Fluorescence Equipment in Acne Patients

Background: Propionibacterium acnes (P. acnes) is a gram positive anaerobic bacteria which plays a key role in the development of acne. Therefore, culture of P. acnes from the acne lesion can serve as an important clinical tool for selecting antibiotics and judging the therapeutic response. However the conventional cultural method is not easy to perform in clinical settings. Objective: The aim of this study was to investigate the clinical application of portable digital skin fluorescence imaging equipment in patients with acne. Methods: Total of 60 objects (33 males and 27 females) with facial acne were recruited. To estimate fluorescence color and size according to the acne lesion, digital fluorescence images were taken and analyzed with image analysis program. Also, we examined the species and the quantification of bacteria aerobically and anaerobically isolated from each kind of acne lesion. Results: Among the bacteria cultured, coagulase negative staphylococci (CNS) was the most common (57.7%), followed by P. acnes (46.1%). Noninflammatory lesions (comedones) showed statistically significant correlation with red fluorescence and inflammatory lesions (papules and pustules) with green fluorescence (p=0.004). The density of CNS and P. acnes were also significantly associated with fluorescence size (p=0.014, p=0.005). However, there was no statistical association between the strains of bacteria and the color of fluorescence (p=0.192). Conclusion: Since the size of fluorescence correlates well with P. acnes levels, we found the noninvasive technique of portable digital skin fluorescence imaging equipment to be useful in choosing adequate antibiotics and monitoring antibiotic therapy in acne vulgaris. (Korean J Dermatol 2008;46(7):889∼895)