CORRELATION OF PROTEIN-LEVELS WITH SKIN PRICK TEST REACTIONS IN PATIENTS ALLERGIC TO LATEX

Background: Natural rubber later (NRL) gloves are the major source of proteins that cause latex allergic reactions in sensitized health care workers and patients. Objective: This study evaluated the effect of m anufacturing changes on reducing protein, antigen, and allergen levels of latex medical gloves. Methods: Three types of NRL gloves were manu factured with a common batch of compounded later. The NRL gloves were analyzed for total protein by using the American Society for Testing a nd Materials D5712-95 Lowry method, and specifically for latex protein s by immunoassay. Allergen levels in the extracts were determined by e nd-point titration skin prick tests (SPTs) on patients allergic to NRL . Results: Extracts from regular powdered gloves had detectable levels of latex proteins and allergens (62% SPT positive), whereas the powde r-free gloves were bw in protein content and allergenicity (5% to 8% S PT positive). No significant difference in SPT reactivity was observed between the chlorinated powder-free gloves and the polymer-coated glo ves. Although the protein levels determined by the Lowly assay correla ted with SPT reactivity (r = 0.95), the test was restricted by a high detection limit (9.3 mu g/ml). Fifty-eight percent of patients allergi c to latex reacted at the 50 mu g/gm detection limit allowed by the Fo od and Drug Administration. The ELISA had a good correlation with SPT reactivity (r = 0.93), and because of the greater sensitivity, gloves testing below the ELISA reporting limit (0.06 mu g/ml) have a signific antly lower potential for. eliciting reactions in patients allergic to latex. Conclusions: Results of protein assays are acceptable criteria with which to rate the potential allergenicity of gloves; however; th e American Society for Testing and Materials D5712-95 assay may lack t he sensitivity to provide clinically relevant data.