This large follow up investigation of healthcare workers in Italy allowed us to evaluate latex related symptoms and sensitisation using powdered latex gloves, and then the progression of symptoms after non‐powdered latex gloves were introduced for all healthcare workers and non‐latex gloves for those subjects sensitised to latex.
Natural rubber latex allergy was a major occupational health concern among healthcare workers until recent years.7,9,21,23,24,25,26
Symptoms related to latex glove use were noticed in 21.8% of the population studied—a level similar to other studies.2,27
reported a 26.7% presence of symptoms in a survey of dental professionals while in 1997, Leung29
found that 30.9% of Hong Kong nurses reported glove related symptoms. The lower percentage in our study could be related (1) to the low mean age and work seniority of our study group, due to the opportunity given to Italian healthcare workers to retire after 15 or 20 years' work in public hospitals; (2) to the “healthy worker effect”, because sensitised people are at higher risk of leaving the workplace.
Substantiating what was previously reported by Turjanma17
the majority of symptoms are mild, while a few are general symptoms related to latex IgE mediated sensitisation (urticaria, asthma, and rhinitis). Latex symptoms are significantly related to a positive history of common allergic symptoms and to family atopy, and less related to atopy as defined by prick test. A high predictive value is obtained through analysis of skin sensitisation to latex, followed by a positive history of allergic symptoms. The increased use of latex gloves increases sensitisation and related symptoms. In line with the findings of other studies,11
workers in operating theatres, laboratories, and centres for haemodialysis are at higher risk.
Follow up showed a significant reduction in latex related symptoms among the group considered, which cannot be explained by differences in work practice variables, such as number of hours of latex glove use or a change in task description. The introduction of non‐powdered latex gloves enables workers to avoid the air contamination30
and the lower latex release of these gloves prevents new cases of sensitisation. The reduction in exposure to latex allergens resulting from the change in gloves led to fewer symptoms such as itching/erythema, but also to a decrease in IgE mediated symptoms, particularly skin reactions, in line with the findings of other studies.30,31
There was also a significant decrease in hand eczema at follow up, just as Edelstam has reported in a similar eight month study. There was a statistically significant reduction in rhinoconjunctivitis—although only a few subjects reported resolution of symptoms, most reported an improvement. The reduction in asthma was not statistically significant, probably indicating a lack of statistical power in the analysis because of the low number of asthmatics in the study.
Our results indicate that simple measures such as the avoidance of unnecessary glove use, the use of non‐powdered latex gloves by all workers, and the use of non‐latex gloves by sensitised subjects can stop the worsening of latex symptoms and can prevent new cases of sensitisation. The powder‐free policy produced the best results in terms of alleviating mild local symptoms (such as itching/erythema and hand eczema) and stopping new sensitisations. For people already sensitised to latex, it is essential to avoid direct contact, but they can work at the same task as long as other workers use non‐powdered latex gloves. The effect of the new gloves was less evident in subjects with IgE mediated symptoms such as asthma and rhinitis, who must avoid all contact with latex. In fact, once sensitisation has occurred, it is difficult to prevent appearance of symptoms, especially in the case of systemic reactions. The role of prevention must be to avoid onset of sensitisation by providing low latex release powder‐free gloves, and to identify those subjects at greater risk (such as asthmatics) who must avoid latex contact altogether and use non‐latex gloves.
There are various important aspects to this study. It is one of the few to systematically enrol an unselected group of healthcare workers and follow them over a three year period, in contrast to previous studies which enrolled selected, volunteer subjects.1,3,5,32,33,34,35
The large sample size enabled us to determine the relative roles played by the various potential risk factors and identify those subjects most at risk so as to introduce preventive measures. In fact, it is vital to screen exposed subjects for latex sensitisation so as to limit their latex exposure as much as possible, and then lower the allergen content of latex products, substitute latex with non‐latex products whenever possible, reduce exposure to the airborne allergen, and avoid unnecessary glove use.
There are also some limitations of the study: subjects who may have developed latex sensitivity may have left the workforce before the study, leading to an underestimation of the prevalence of latex sensitivity. Selection bias was also possible if non‐participants differed somehow from participants, or if those who thought that they were symptomatic or sensitised to latex were more likely to participate, which could result in an overestimation of risk estimates. Although we were unable to interview non‐participants, table 1 suggests that the groups were essentially identical in several key characteristics. In the follow up group, those lost were younger and reported more allergic symptoms than the others. Therefore our results could in fact underestimate latex symptoms.