Allergic contact dermatitis from natural latex

Background: Reports on natural latex allergy have increased steadily during the last 10 years. Latex allergy generally refers to a type 1 reaction to natural rubber latex (NRL) proteins with clinical manifestations ranging from contact urticaria to asthma and anaphylaxis. Previous United States studies on NRL allergy largely have been reported by allergists with little detailed information on hand eczema, contact allergy, or on outcome. The present study was performed from March 1998 to November 1999 with the aim of finding out the prevalence of type IV hypersensitivity to latex in patients with suspected rubber allergy. Materials and methods: A total of 167 patients with hand eczema and contact with rubber products underwent patch testing with the standard screening and rubber components (test series Deutsche Kontaktallergiegruppe), and NRL pure provided by Regent (liquid high ammonia 0.7% NRL, accelerator, and preservative-free latex) between March 1998 and November 1999. The charts of all NRL positive patients are reported with the results of history, prick, patch tests, total IgE, specific IgE to latex (FEIA) test and follow-up data (after 6 months). Results: Four patients (3 men) showed positive patch test results to NRL. One of these patients also reacted to the rubber chemical tetraethylthiuram monosulfide, and another one of these patients revealed a type 1 reaction to NRL, diagnosed by positive reaction to prick test. The other 3 patients with patch test reactions to NRL had negative reactions to prick tests to NRL extracts after 20 minutes. All 4 patients had a positive delayed prick test reaction to NRL. Latex FEIA test result was negative in all 4 patients. The contact eczema healed after elimination of the latex gloves and medical latex devices in all patients. Furthermore, 10 of the 167 patch testing patients (6%) were positive for tetramethylthiuram monosulfide 1%. Conclusion: In the present study with 167 patients, the prevalence of type IV hypersensitivity to latex was 2.4%. We recommend that the patch test with NRL as well as with rubber additives should be performed in patients of suspected contact dermatitis caused by rubber products.