A Study on Provocation Test by Cat Contacts

Lee, Chang Woo; Ryu, Jeong Woo; Yum, Hye Yung; Jeoung, Byeung Ju; Kim, Kyu Earn; Lee, Ki Young

Abstract

PURPOSE
Cat is the pet which many of us quite frequently contact without any specific precautions. According to the allergy skin tests conducted in children, cat antigen shows a comparatively high positive reaction, and past history also shows that there are many patients who suffer allergies from cat contacts. Therefore, once it is diagnosed as an allergy caused by cat, it is important that patients be isolated in order to restrict their contact with cat. In this context, this study was conducted for the purpose of finding out how serious and how frequent the allergies by cat contacts are.
METHODS
Forty five children patients who visited to the Allergy Clinic for Children, Severance Hospital annexed to the Medical College, Yonsei University were enrolled in this study. Some of patients had shown a positive reaction against cat antigen in the allergy skin test, and others had a past history of developing symtoms when contacted by cat. The patients were isolated from cat for seven days, and then contacted with cats for 30 minutes and observed the provocated symptoms.
RESULTS
1) Among the tested patients, the number of cases who were provocated by the symptoms after cat contact were 18 (40%). 2) Among those patients who were shown to be positive only in allergy skin test, only 24.2% proved to be provocated by the symptoms, while 90.0% of those who had a past history in addition to allergy skin test proved to be provocated by the symptoms. 3) Symptoms provocated after cat contact showed allergic rhinitis patients 88.2% which was the highest ratio, bronchical asthma, 35.3%, urticaria, 29.4%, and allergic conjunctivitis, 23.5%, respectively. 4) The onset and duration of symptoms provcated were under 10 minutes and from 30 to 60 minutes, which included most cases in the test. 5) Total IgE and eosinophil count of patients did not show any meaningful differences between the group which was provocated and that which was not provocated.
CONCLUSION
It was shown that 40% patients who were suspected of cat allergy had a positive reaction to the cat contact provocation test. Ninety percents of patients who showed both positive allergy skin test and past history were provocated after cat contact.