Antigenic proteins in latex glove extracts: sources of variability

Antigenic protein levels in commercially available latex medical gloves were studied. For comparison, the gloves were divided into four main groups; powdered examination, powder-free examination, powdered surgical, and powder-free surgical. Residual protein levels of 91 different glove brands were determined using the LEAP (latex ELISA for antigenic proteins) assay and found to be extremely variable. The possible sources of variability were investigated. Lot-to-lot variability was determined by testing multiple lots of five different brands of surgical gloves. The authors also determined glove-to-glove variability, variability within an individual glove, and test-method variability. It was observed that lot-to-lot variability (25-61% relative standard deviation--RSD) and glove-to-glove variability (51% RSD) were of similar magnitude and accounted for most of the variability found within a given brand of gloves. However, the greatest source of variability identified was brand-to-brand variability (143-283% RSD).