Frequency of natural rubber latex allergy in adults is increased after multiple operative procedures

Background: It has been shown that immediate-type allergy to natural rubber latex (NRL) affects predominantly health-care workers and infants with mal formations requiring repeated medical procedures. Adult patients with multi ple invasive procedures are not thought to be at an increased risk of NRL a llergy. Methods: A total of 325 consecutive adult inpatients (54.4 +/- 15.6 years; 219 men, 106 women) awaiting surgical or urologic procedures were assessed by questionnaire-based history (atopic diseases, number of previous standar d operative or endoscopic procedures, intolerance to rubber products, and a dverse reactions during medical care), by skin prick tests with different N RL test solutions, by measurement of NRL-specific IgE in the serum, and, if sensitization to NRL was found, by cutaneous challenge tests with NRL-cont aining material. Subjects were classified as sensitized to NRL if skin pric k test reactions to NRL were positive or if NRL-specific IgE antibodies wer e found. NRL allergy was defined as NRL sensitization and immediate-type sy mptoms to NRL. Results: Thirty-one of 325 (9.5%) subjects were found to be sensitized to N RL, 14/285 (4.9%) by skin prick testing and 23/323 (7.1%,) by NRL-specific IgE antibodies in the serum. Four individuals (1.2%) were diagnosed as havi ng clinically manifest NRL allergy, and another 27 (8.3%) were sensitized t o NRL without symptoms to date. The frequency of previous invasive procedur es was zero in eight patients, up to 10 in 245, 11-20 in 52, 21-30 in seven , and over 30 (up to 83) in 13 patients. No association was found between t he number of invasive procedures and NRL sensitization without clinical sym ptoms. However, 3/4 patients with NRL allergy had undergone more than 30 in terventions, and 1/4 had had I I operations. Frequent invasive procedures ( more than 10) were significantly associated with NRL allergy (P < 0.001). A llergy or sensitization to NRL was associated with atopy (21/31 vs 87/294) (P < 0.001). Conclusions: A remarkable percentage of unselected adult patients undergoin g surgical procedures have allergy or sensitization to NRL. Repeated invasi ve treatment appears to be a risk factor for NRL allergy.