Are dermatoscopes a potential source of nosocomial infection in dermatology clinics?

Conflict of interest: the authors declare that they have no conflicts of interest. Dermatoscopes are often directly applied on patients’ skin during dermatology examinations and could therefore act as potential vectors of infection. Nosocomial or hospital‐acquired infections are a considerable health hazard, one third of which are preventable.1 Previous studies have implicated contact medical instruments as vectors of nosocomial infection, including stethoscopes contaminated with Staphylococcus species.2 We wanted to determine whether dermatoscopes might harbour potentially pathogenic organisms that could result in transmission of infection. The ATP bioluminescence assay (ATPBA) is used for rapid monitoring of cleanliness. It is based on the principle that all living organisms release ATP and the light generated by ATP measured in relative light unit (RLU) correlates with the amount of organic material and hence the cleanliness of a surface. Use of ATPBA in monitoring environmental cleaning in hospitals was proposed by Griffith et al.3 We used microbiological sampling and ATPBA to monitor microbial and organic contamination of dermatoscope lenses. We sampled 9 hand‐held contact dermatoscopes (Delta models 10 and 20; Heine, Herrsching, Germany) on 60 occasions (30 samples taken immediately before the start of each clinic, matched with 30 samples taken immediately at the end of these clinics) over a 4‐month period by each of the two methods without prior knowledge of the clinicians. An alcohol hand gel (Spirigel®; Ecolab Ltd, Leeds, West Yorkshire, UK) containing 70% denatured ethanol was used as contact fluid during dermoscopy.