344 Abstracts .I. ALLERGY Cl.IN !MMUNOL JANUARY 1991

817 ALLERGEN EXPOSURE AND RESPIRATORY VIRUS INFECTIONS IN YOUNG WHEEZY CHILDREN T.T.Vanto. M.D.. T-P&D.. J&&&Q& . . M.D.. 0. Re M.D., Turku.

Fifty-four patients aged from 1 to 6 years with 22 previous wheezing attacks were prospectively followed for 3 months to assess the relation between allergen exposure, virus infections and wheezing episodes. Serum IgE was 22 SD above the normal in 31 patients. Skin prick tests with cat, dog and mite were positive in 19, 17 and 6 % of the patients, respectively. Pets in the homes were ram: one had a cat and none had a dog. Consequently, allergen levels in dust samples from the homes were low: major cat allergen, Fe1 d I 22 fig/g was detected in 4 96, dog allergens ~20.000 IU/g in 4 %, and a mite allergen, Der p I 22 fig/g in 10 56. Allergen exposure was not associated with the symptoms during the follow- up. Highest levels of allergens were detected in the homes of non-sensitized patients. Of the 73 wheezing episodes during the follow-up, 85 % were stated by the parents to be caused by an infection, and only 34 96 by an allergen exposure. Virus or Mycoplasma pneumoniae-infections were diagnosed in 29 (40 %) of the episodes. Tbe results suggest that proper allergen avoidance is feasible and that allergen induced wheezing may thus be minimized. The association of wheezing episodes with viral infections was confirmed.

818 CORRELATION BETWEEN HISTORY OF ALLERGIC SYMP-

TOMS AND TYPE I SENSITIZATION N CHILDREN. &.

KuLMs,LRitlLM.L.etLL&GELK.. ph. L Paris, France, Hamburg and Munich, Germany

Allergic symptoms are increasingly often reported,

even in early age. In an epidemiologic pilot study in

Bavaria , 46.3% (278/601) of 5-6 years old children had

a history of “allergy” or “atopy” as evaluated by questi-

onnaire (rhinitis/conjunctivitis 11.9%. asthma 4%, other

“allergic” diseases 28%). Skin prick tests with six corn

mon allergens were performed to evaluate the percenta

ge of immunologically mediated reactions. Using the

combination of cat-, house dust mite- and grasspollen

allergen, 63.2% of the children with history of rhinitis/

conjunctivitis showed positive skin tests, 77.8% of the

patients quoting asthma, but only 16% of those reporting

“other allergies”. Children with symptoms of food intole-

rance (9.9% of the sample) reacted in 4.1% to egg or

milk. The sensitization pattern varied according to the

symptoms. In seasonal or perennial rhinitis/conjunctivitis,

pollen sensitization predominated, whereas in asthma, cat

and mite were the most prevalent allergens. We conclu-

de, that anamnestic data concerning “allergic” diseases

must be cautiously interpreted. Children reporting respi-

ratory symptoms have a relatively high percentage (>60%)

of positive skin tests to airborne allergens suggestive of

a true allergic disorder. Whether other “allergic” symp

toms are more likely to be of unspecific nature or just

require a larger skin test reperoire remains to be eluci-

dated.

Most research on the adverse effects of ozone has focused on pulmonary function and lung cells. However, a substantial amount of inspired ozone is removed in the nasal cavity. Therefore we evaluated the e&eta of ozone on human nasal epithelial cells (HNE) by both the release of lactate dehydrogenase (LDH) and morphological changes. The cells were exposed in vitro for 3 hrs to ozone at 0.600,0.266, or 0.106 ppm or air.

Scanning electron microscopy showed that cultured, air exposed HNE formed a contiguous flat sheet with microvilli on their apical membranes. Exposure to ozone caused desquamation and rounding up of a small proportion of the cells.

Exposure of HNE to ozone at 0.500 ppm caused a significant release of LDH; 27.4 f 9.2 vs 12.2 f 5.7 1u/106 cells, ozone vs tir exposure (~<o.ooI). Using analysis of covariance it was found that ozone caused a concentration dependent release of LDH (mean slope = 22.4 IV/l06 cells-ppm, SE = 2.6, pe 0.661) and that LDH release varied signi%antiy among specimens (p<O.601). These studies show that ozone produces a dose-dependent cytotoxic release of LDH from HNE. although specimens from subjects vary in their susceptibility (p = 0.006). Morphologic changes were minor and less marked than previously seen with A549 alveolar epithelial cells.

820

K.Oberla*, Nunich*, Hamburg**, Germany With reuard to alleruic sensitization, the

first months of life se& to be a vulnerable period. So, an influence of the NE on the development of skin sensitivity to aeroallergens and of respiratory allergic disease (RAD) has been discussed. However, studies, couparing the HB of patients with RAD to that of the whole population, yielded conflicting results. In 1988 and 1989 we investigated an unselected population of 1066 Bavarian pre-school children (5 to 6 years old) using aeroalleriens

skin prick test with four (grass and birch pollen, house

dust mite, cat epithelia) . The presence of allergic rhinoconjunctivitis, bronchial asthma or atopic eczema was assessed by a questionnaire and by direct examination. Positive prick test reactions to the aeroallergens mentioned above were seen in 15.4/9.2/12.2/10.4%, manifestations of the atopic diseases were found in 11.7/4.5/22.2%. Seperate evaluation of 148 distributions of children reacting or not reacting to the allergens tested and of those with or without a history of an atopic disease did not yield significant differences (chi-square tests: p 1 0.3). Thus, among a coherent group of children, MB did not correlate to allergic sensitization nor manifest atopic disease. These findings contrast to those of others and may be explained by differing climatic influences or the stringent study design.