Quantitative analysis of residual protein contamination of podiatry instruments reprocessed through local and central decontamination units

The residual protein of 189 instruments reprocessed centrally and 189 instruments reprocessed locally was determined using a fluorescent assay based on the reaction of proteins with o-phthaldialdehyde/sodium 2-mercaptoethanesulfonate.Residual protein was detected on 72% (n = 136) of instruments reprocessed centrally and 90% (n = 170) of instruments reprocessed locally. Significantly less protein (p < 0.001) was recovered from instruments reprocessed centrally (median 20.62 μg, range 0 - 5705 μg) than local reprocessing (median 111.9 μg, range 0 - 6344 μg).Overall, the results show the superiority of central reprocessing for complex podiatry instruments when protein contamination is considered, though no significant difference was found in residual protein between local decontamination unit and central decontamination unit processes for Blacks files. Further research is needed to undertake qualitative identification of protein contamination to identify any cross contamination risks and a standard for acceptable residual protein contamination applicable to different instruments and specialities should be considered as a matter of urgency.The decontamination processes for medical instruments are under constant review as new challenges to instrument reprocessing emerge due to the increasing complexity of instruments and the emergence of variant Creutzfeldt Jackob disease (vCJD) which demonstrates reduced susceptibility to the common microbial inactivation processes [1]. Investigations into the biological properties of prion protein have highlighted the importance of the cleaning phase to remove protein and debris [2,3]. Moreover, the presence of residual protein on surgical instruments has been shown to increase the dissolution of metal ions, therefore increasing the rate of corrosion of certain instrument stainless steel [4]. In addition, residual protein may promote the adhesion of bacteria through specific adhesion receptors, such as fibronectin binding protein found