A. Lanteaume

Prevalence of allergy to hymenoptera stings in different samples of the general population

To get figures of prevalence of systemic reactions (SRs) to hymenoptera sting in adults between the ages of 18 to 65 years, we performed three different surveys using the same questionnaire from 1984 to 1988. The first one was a door-to-door survey in Southeast France, which included 8271 adults and used a questionnaire. The second one, which included 2067 adults, was performed in a health care center and comprised the same questionnaire and venom skin tests in subjects reporting a history of SRs. The third survey was a national poll performed through a home-based national computer network. The percentage of SRs ranged from 0.66% in the second survey including skin tests to 3.3% in the poll survey. The higher prevalence figure in this latter survey may be related to a false-positive history. There was no urban-rural difference in prevalence of SR.

Reliability of respiratory symptoms to diagnose atopy.

As reliance of responses to epidemiological questionnaires on atopic symptoms is doubtful, we studied the predictive value of these questions relative to atopy, defined by the presence of serum specific IgE, taking into account some extraneous variables such as age and sex. The study population included 2067 adults, 20‐60 years old. The protocol consisted of a standardized questionnaire and an evaluation of serum specific IgE using the Phadiatop® (Pharmacia Diagnostics, Uppsala, Sweden) test. The predictive value of each symptom suggestive of atopy was quite low, but was much dependent on age and sex. Women more often than men reported atopic symptoms in the absence of atopy. Similarly, the predictive value of each symptom decreased with age. Thus atopic symptoms do not have the same value as predictors of atopy. These findings have both clinical and epidemiological important implications.

Housing and house‐dust mites

Because the mite‐allergen content in homes is highly variable even in the same geographic area, we tried to determine which variables influence mite infestation. We evaluated mite‐allergen content in bedding relative to housing conditions and living habits. This cross‐sectional study included 108 homes. Housing conditions were assessed by an architect and living habits by a researcher specialized in social and family economics. Group I allergen level was measured on the mattress dust with monoclonal antibodies, and relative humidity (RH) was monitored in the bedroom during a 2‐week period. Homes with low RH did have low mite‐allergen content. In contrast, homes with intermediate RH levels had very variable mite‐allergen content. Using analysis of variance and a logistic regression analysis, we were unable to identify any variable predictive of mite‐allergen content. Thus, factors other than relative humidity seem to influence mite infestation. Moreover, the absence of association between mite infestation and ventilation rate might be accounted for by the gentle climate in our area with notable outdoor RH.

Sex difference in Fel d 1 allergen production

BACKGROUND Previous experiments have shown that in vivo Fel d 1 production is under hormonal control. It strongly decreased 1 month after castration of male cats and increased after testosterone injection. OBJECTIVE These results led us to put forward the hypothesis that Fel d 1 production could be more important in male that in female cats. Five adult male and five adult female cats were studied. METHODS On day 0 three separate sites of each cats trunk were shaved, and a 5.72 cm2 area in each site was washed twice (D0a and D0b) with 5 ml of distilled water. Then a collar was attached to the neck to prevent contamination from saliva. Twenty-four hours later on day 1, all areas were washed again once (D1a). Skin washes and fur extracts from the shaved areas were evaluated for Fel d 1 content. The same procedures (apart from collection of fur) were repeated 5 months later. RESULTS The Fel d 1 level was higher in the first skin wash of male cats compared with that of female cats on each separate site of the trunk in both experiments, initially and 5 months later. Results were significant in the first experiment (median Fel d 1 per milliliter: 69.4 and 28.9 mU, respectively, for the combined three sites; p < 0.05). Fel d 1 production over a 24-hour period was higher in male cats, but the difference did not reach statistical significance. Furthermore, correlation between Fel d 1 levels in washes D0a and in fur was highly significant (p < 0.01). CONCLUSION These results confirm that Fel d 1 originates from skin. Furthermore, they suggest that Fel d 1 production is higher in male than in female cats.

Cat sex differences in major allergen production (Fel d 1)

ies by condurango bark indicates cross-reactivity between condurango bark and NRL. Up to now, definite proof of clinically relevant cross-reactivity between NRL and food by both positive oral challenge tests and inhibition tests has been reported only for banana4, 5 and chestnut.6 We here add condurango bark to the list of orally administered substances with proven cross-reactivity to NRL. In view of the high prevalence of NRL allergy and the not uncommon use of condurango bark, allergic reactions to the latter may be more frequent than this single case report suggests. REFERENCES