Clinical relevance is associated with allergen-specific wheal size in skin prick testing.

BACKGROUND: Within a large prospective study, the Global Asthma and Allergy European Network (GA(2) LEN) has collected skin prick test (SPT) data throughout Europe to make recommendations for SPT in clinical settings. OBJECTIVE: To improve clinical interpretation of SPT results for inhalant allergens by providing quantitative decision points. METHODS: The GA(2) LEN SPT study with 3068 valid data sets was used to investigate the relationship between SPT results and patient-reported clinical relevance for each of the 18 inhalant allergens as well as SPT wheal size and physician-diagnosed allergy (rhinitis, asthma, atopic dermatitis, food allergy). The effects of age, gender, and geographical area on SPT results were assessed. For each allergen, the wheal size in mm with an 80% positive predictive value (PPV) for being clinically relevant was calculated. RESULTS: Depending on the allergen, from 40% (blatella) to 87-89% (grass, mites) of the positive SPT reactions (wheal size ≥ 3 mm) were associated with patient-reported clinical symptoms when exposed to the respective allergen. The risk of allergic symptoms increased significantly with larger wheal sizes for 17 of the 18 allergens tested. Children with positive SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10 mm depending on the allergen. CONCLUSION: These 'reading keys' for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form with the standard allergens including mm decision points for each allergen is offered for clinical use.

Comparison of cetirizine, ebastine and loratadine in the treatment of immediate mosquito-bite allergy.

BACKGROUND: People frequently experience whealing and delayed papules from mosquito bites. Whealing is mediated by antisaliva immunoglobulin (Ig)E antibodies and histamine. Cetirizine, ebastine and loratadine have earlier shown effects on mosquito-bite reactions but no comparative studies exist. METHODS: A double-blind, placebo-controlled, cross-over study was performed with cetirizine 10 mg, ebastine 10 mg and loratadine 10 mg in 29 mosquito-bite-sensitive adults exposed to Aedes aegypti mosquito-bites. The size of the bite lesion and the intensity of pruritus (visual analog scale) were measured at 15 min and 2, 6 and 24 h. RESULTS: Cetirizine and ebastine, but not loratadine, decreased significantly the size of whealing (P < 0.01) and accompanying pruritus (P < 0.001) compared to placebo. Cetirizine was most effective on pruritus but caused more often sedation than ebastine or loratadine. The delayed bite symptoms remained too faint for any statistical comparison. CONCLUSION: This comparative study in mosquito-bite-sensitive adults shows that cetirizine and ebastine decrease significantly whealing and accompanying pruritus, and that cetirizine seems to be the most effective against pruritus.

Occupational allergic contact urticaria to yucca (Yucca aloifolia), weeping fig (Ficus benjamina), and spathe flower (Spathiphyllum wallisii).

BACKGROUND: Occupational contact urticaria (CU) from plants is often reported, but it is less often attributed to decorative houseplants. We present an atopic gardener and caretaker of plants who developed CU when occupationally exposed to weeping fig, spathe flower, and yucca. METHODS: Sensitization was evaluated by skin prick tests (SPT) and analyses for IgE antibodies. RESULTS: SPT were positive to all three plants, and IgE antibodies were found to weeping fig and spathe flower. SPT were also performed with several decorative houseplants in more than 600 patients. Positive SPT was found to weeping fig (12%), African milk tree (8.3%), yucca (5.8%), Chinese rose (4.7%), massangana (4.6%), bird's nest fern (3.2%), and spathe flower (3.2%). CONCLUSION: Our study indicates that SPT and tests for IgE antibody are useful in detecting occupational CU caused by houseplants.

A baker's occupational allergy to flour moth (Ephestia kuehniella).

BACKGROUND: Allergy to insects is common. However, few reports cover occupational sensitization to flour moth (Ephestia [syn. Anagasta] kuehniella). We describe a baker who suffered from IgE-mediated occupational respiratory allergy to flour moth. METHODS: The skin prick test (SPT) and serum IgE tests were used to evaluate the patient's sensitivity to flour moth. Allergen cross-reactivity with mites was evaluated in IgE-inhibition studies. Clinical sensitivity was evaluated by nasal challenge test. Pulmonary function tests were repeatedly monitored. RESULTS: SPT with flour moth gave a 6-mm wheal, and an elevated level of flour moth-specific IgE was measured in the patient's serum (1.9 PRU/ml, RAST class 2). Immunoblotting with the patient's serum revealed at least seven heavy IgE-binding bands with molecular masses of 22, 35, 43, 53, 65, 77, and >86 kDa in the extract of flour moth. Allergen cross-reactivity with mites was demonstrated in inhibition studies. Immediate-type allergy to flour moth was confirmed by nasal challenge. Increased daily variability of PEF values was observed during workplace exposure. CONCLUSION: A baker's occupational respiratory allergy to flour moth was confirmed.

Loratadine in the treatment of mosquito-bite-sensitive children.

BACKGROUND: Children frequently experience harmful whealing and delayed papules from mosquito bites. Whealing is mediated by antisaliva IgE antibodies and histamine, but the effect of antihistamines on mosquito-bite symptoms has not been evaluated in children. METHODS: The effect of loratadine (0.3 mg/kg) was examined in 28 mosquito-bite-sensitive children (aged 2-11 years). The double-blind, placebo-controlled, crossover study was performed with exposure to Aedes aegypti laboratory mosquitoes. The size of the bite lesion and the intensity of pruritus (visual analog scale) were measured at 15 min and at 2, 6, and 24 h. RESULTS: Loratadine decreased the size of the wheals by 45% (P < 0.001, 25 children) and accompanying pruritus by 78% (P = 0.011, 12 children) at 15 min compared to placebo. The size of the 24-h delayed bite lesion also decreased significantly (P = 0.004), but there was no change at 2 or 6 h. Loratadine was well tolerated and no marked side-effects were recorded. CONCLUSIONS: This study in children shows that prophylactically given loratadine decreases significantly the whealing and pruritus caused by mosquito bites and also reduces the size of the 24-h bite lesions. Therefore, the therapeutic profile of loratadine extends from immediate to delayed allergic symptoms in mosquito-bite-sensitive children.

Treatment of mosquito bites with ebastine: a field trial.

Wealing and pruritic, long-lasting papules are a common nuisance from mosquito bites. Antihistamines can be expected to decrease wealing, but their effect on the delayed bite symptoms needs to be elucidated. We studied the effect of ebastine in 28 mosquito-bite sensitive adult subjects exposed to Aedes communis bites in the field. Ebastine 20 mg and placebo were given for 4 days in a cross-over fashion, and the size of the bite lesion and the intensity of pruritus (visual analogue scale) were measured at 15 min and 2, 6 and 24 h after the bites. Ebastine decreased significantly (p <0.001) the size of the bite lesion and pruritus at 15 min. Ebastine also had a significant effect (p<0.01) on pruritus at 2 and 24 h, and this effect was highly significant when the measurements at all 4 time points were pooled. Five patients (18%) on ebastine, but none on placebo, experienced sedation (ns). The present field study shows that ebastine 20 mg given prophylactically is effective against immediate mosquito bite symptoms, and that it also significantly decreases pruritus associated with the delayed bite papules.

Immediate contact allergy from hydrolyzed wheat in a cosmetic cream.

Immediate contact allergy to cosmetics seems to be rare, since only a few case reports on it have been published. We report on a case of IgE-mediated allergic contact urticaria caused by hydrolyzed wheat in a body cream.

Effect of ebastine on mosquito bites.

Mosquito bites usually cause wealing and delayed bite papules. Cetirizine decreases wealing, bite papules and pruritus but the effect of other antihistamines on mosquito bites is unknown. We studied the effect of ebastine in 30 mosquito bite-sensitive adult subjects. Ebastine 10 mg or 20 mg and placebo were given for 4 days in a cross-over fashion. Aedes aegypti bites were given on forearms. The size of the bite lesions and pruritus (visual analogue score) were measured at 15 min, 2, 6, and 24 h after the bites. Twenty-five subjects were evaluable in the study. At 15 min ebastine decreased significantly the size of the bite lesion (p = 0.0017) and pruritus (p<0.0001). The effects of 10 mg and 20 mg of ebastine were similar. No significant effect was found at 2, 6 or 24 h, but when the measurements at all four time points were compiled the size of the bite lesion and pruritus score decreased significantly. Sedation occurred during ebastine treatment in 6 (21%) and during placebo treatment in 2 (7%) subjects. The present results show that prophylactically given ebastine is effective against immediate mosquito bite symptoms.