Skin Prick Test Sensitivity Research Articles

PETS AND ATOPIC DISORDERS IN INFANCY

SUMMARYThis population‐based prospective study assessed the relationship between pets and atopic disorders in infancy. One or more pets were found in 61.4% of households. Pets were found in homes with a family member affected by asthma or rhinitis as often as in homes with no allergy in the family. The presence of pets was not shown to affect the development of atopic manifestations in the first 12 months of life. Infants exposed to cats developed skin prick test sensitivity to cat dander significantly more often (p=0.01) than those infants who had had no such exposure.

Breed-specific dog-dandruff allergens

Fifty-one patients with clinical history of dog allergy were skin prick tested with eight individual standardized dog breed-allergen preparations, one mixed breed-allergen preparation (Poodle/Alsatian), dog-serum albumin, and histamine hydrochloride, 1 mg/ml. All extracts were characterized by crossed immunoelectrophoresis and crossed radioimmunoelectrophoresis with a pool of sera from patients clinically sensitive to dog. The dog-breed extracts contained common antigens/allergens, as well as components represented only in one or two dog-breed extracts. The concentration corresponding 1000 BU/ml varied from 16 to 100 μg of protein per milliliter. The sensitivity of skin prick test was 67% to 88% for the various dog breed-allergen preparations, but only 18% for dog-serum albumin. Significant difference between the skin test response to different dog breed-allergen preparations indicating dog breed—specific allergens was obtained in 15% of the patients. There was no significant correlation between skin prick test results and symptoms related to a specific dog breed.

Diagnosis and immunotherapy of mould allergy

The IgE-response was evaluated by skin prick test, bronchial provocation test and RAST in a 1-year placebo-controlled double-blind immunotherapy study. Eleven adult asthmatics were treated with a Cladosporium allergen preparation and 11 comparable patients received histamine placebo. The bronchial sensitivity (PC20) decrease greater than 0.5 log step in 8/11 (73%) Cladosporium-treated versus 3/11 (27%) in the placebo group. Corresponding figures for skin prick test sensitivity was 10/11 (91%) and 1/11 (9%) respectively. Circulating IgE showed a temporary boost in the Cladosporium group and then values approaching the pretreatment value. Only minimal and insignificant changes were found in the placebo-treated patients. Changes in IgE-reactivity were not related to allergen dose, clinical efficacy or to the occurrence of side effects. Some interrelation between changes in skin prick test, bronchial provocation test and RAST was found indicating a differentiated effect of immunotherapy on various IgE compartments. In spite of the pathogenetic role of IgE in allergic diseases, changes in IgE-reactivity do not seem directly involved in the mechanisms underlying the clinical efficacy of immunotherapy but might be of importance in a complex interaction with other immunological parameters.

Reproducibility of skin sensitivity using a quantitative skin prick test.

The reproducibility of repeated quantitative skin prick test titrations was evaluated in seven asthmatic patients tested 2-4 times within 6 weeks. The skin sensitivity was estimated as endpoint titration and histamine equivalent reaction using both 1 and 10 mg/ml histamine dihydrochloride. The histamine equivalent reaction had a significantly higher reproducibility compared to endpoint titration, with a coefficient of variation less than 10% for histamine 10 mg/ml. Further, using this histamine concentration, the deviation in repeated testing was for practical purposes less than 0.5 log step. The same constancy in skin sensitivity was found in one patient tested 3 times and then retested another 3 times 6 months later by a different tester. The results indicate that the quantitative skin prick test and histamine-estimated skin sensitivity have a clinical application in the assessment of pharmacologically or immunotherapy-induced changes in the releasability of skin mast cells.