IgE-dependent reactions to urologic catheter extracts by skin testing in latex-allergic patients

Latex allergy is mediated by residual IgE-binding proteins found on latex products. While most reported reactions involve latex gloves, the allergenic potential of other latex containing devices is unknown.

To assess the allergenic potential of latex urologic catheters.

Two identical lots of urologic catheters were extracted in sterile saline and analyzed for latex protein content using sensitive ELISA and Western blot assays. The extracts were tested by skin prick testing in a population of 47 latex-allergic patients.

Latex proteins were detected by ELISA assay, however, the Western Blot method was not sensitive enough to measure latex proteins in these catheter extracts. Skin prick testing using a standard latex reagent (Bencard) demonstrated the test population to be extremely sensitive to latex as 68% of the population reacted to a 1/100,000 dilution. Using undiluted catheter extracts, only 11% of these latex-allergic patients reacted to catheter lot A and 2% to catheter lot C, by prick skin test. Eight percent of the control patients had a positive latex prick skin test and none reacted to the catheter extract.

The data suggest that processing and leaching of these specific latex urologic catheters resulted in a very low latex allergen content. The low prevalence of skin test reactivity in a population of latex-allergic patients suggests that these catheters would be an unusual cause of allergic reactions. It is not possible, however, to determine whether latex-allergic patients could safely use latex urologic catheters.