Background: It has been shown that immediate-type allergy to natural rubber latex (NRL) affects predominantly health-care workers and infants with malformations requiring repeated medical procedures. Adult patients with multiple invasive procedures are not thought to be at an increased risk of NRL allergy.
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 standard operative or endoscopic procedures, intolerance to rubber products, and adverse reactions during medical care), by skin prick tests with different NRL test solutions, by measurement of NRL-specific IgE in the serum, and, if sensitization to NRL was found, by cutaneous challenge tests with NRL-containing material. Subjects were classified as sensitized to NRL if skin prick test reactions to NRL were positive or if NRL-specific IgE antibodies were found. NRL allergy was defined as NRL sensitization and immediate-type symptoms to NRL.
Results: Thirty-one of 325 (9.5%) subjects were found to be sensitized to NRL, 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 having clinically manifest NRL allergy, and another 27 (8.3%) were sensitized to NRL without symptoms to date. The frequency of previous invasive procedures 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 the number of invasive procedures and NRL sensitization without clinical symptoms. However, 3/4 patients with NRL allergy had undergone more than 30 interventions, and 1/4 had had 11 operations. Frequent invasive procedures (more than 10) were significantly associated with NRL allergy (P<0.001). Allergy or sensitization to NRL was associated with atopy (21/31 vs 87/294) (P<0.001).
Conclusions: A remarkable percentage of unselected adult patients undergoing surgical procedures have allergy or sensitization to NRL. Repeated invasive treatment appears to be a risk factor for NRL allergy.