Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study

Background

The query "are there animals at home?" is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization.

Methods

Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog.

Results

A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150-20.75%) or indirect contact (103-14.25%), in 111 subjects (15.35%) any contact was reported.

Conclusions

Only 213 patients (29.46%) would be classified as "exposed to animals" and 510 (70.54%) as "not exposed" according to usual query. Our classification has shown that many "not-exposed" subjects (399-55.19%) were "really exposed". The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals.

Allergic sensitization to common pets (cats/dogs) according to different possible modalities of exposure: an Italian Multicenter Study

Background

The query “are there animals at home?” is usually administered for collecting information on anamnesis. This modality to consider exposure to pet allergens constitutes a potential bias in epidemiological studies and in clinical practice. The aim of our study was to evaluate/quantify different modalities of exposure to cat/dog in inducing allergic sensitization.

Methods

Thirty Italian Allergy units participated in this study. Each centre was required to collect the data of at least 20 consecutive outpatients sensitized to cat/dog allergens. A standardized form reported all demographic data and a particular attention was paid in relieving possible modalities of exposure to cat/dog.

Results

A total 723 patients sensitized to cat/dog were recorded, 359 (49.65%) reported direct pet contact, 213 patients (29.46%) were pet owners, and 146 subjects (20.19%) were exposed to pets in other settings. Other patients were sensitized by previous pet ownership (150–20.75%) or indirect contact (103–14.25%), in 111 subjects (15.35%) any contact was reported.

Conclusions

Only 213 patients (29.46%) would be classified as “exposed to animals” and 510 (70.54%) as “not exposed” according to usual query. Our classification has shown that many “not-exposed” subjects (399–55.19%) were “really exposed”. The magnitude of exposure to pet allergens at home is not related exclusively to pet ownership. These considerations should be taken into account during the planning of epidemiological studies and in clinical practice for the management of pet allergic individuals.

[Have the prevalence and incidence of occupational asthma and rhinitis due to laboratory animals declined in the last 25 years?]

Data for time trends in the prevalence of occupational asthma (OA) and rhinitis (OR) are not known. To investigate trends in the prevalence and incidence of OA and OR over time, we reviewed the available literature. We analysed 15 cross-sectional and 4 longitudinal studies published from 1980 to 2006. In workers exposed to laboratory animals (LA) the prevalence of OA ranged from 2.2% to 11.7%; the prevalence of OR ranged from 6.7% to 41.7%. When we analysed prevalence by study date using a logistic model, the estimated prevalence of OA declined from 8.7% in 1976 to 4.2% in 2001 (p < 0.003), which is -1.8% every ten years. The prevalence of OR rose slightly from 18.5% in 1976 to 19.7% in 2001 (NS). In four longitudinal studies the incidence of OA ranged from 0.4 to 3.5/100 person years, while the incidence of OR ranged from 2.0 to 10.1/100 person years. No clear trend emerged over time. This review shows a trend toward a progressive decline in the prevalence of occupational asthma due to laboratory animals, which may be due to the reduction of exposure since the early 1980s. A further reduction of exposure is needed to prevent the onset of occupational rhinitis.

[Latex allergy in hospital workers--follow-up of symptomatic subjects]

Latex allergy may be manifested in a variety of clinical disturbances such as contact urticaria, angioedema, rhinoconjunctivitis, asthma, and anaphylactic reactions. The aim of this follow-up study was to determine whether a change in glove use from powdered to powder-free latex gloves at previously surveyed hospital workers reduced the work-related symptoms. 53 hospital workers with work-related symptoms where followed up 4,6 years after first investigation. On re-examination, 54.7% use both powdered and powder-free gloves, 37.7% used only latex free gloves and 7.6% stopped the glove use. At follow-up, in 68% of subjects there was the remission or the improvement of work-related symptoms. The improvement of symptoms was greater in workers using powder-free gloves than in others (p < 0.005). In conclusion our study shows that preventive measures, such as the use a powder-free latex gloves, are sufficient to induce a reduction of work-related symptoms.