Utility of additional skin testing in "nonallergic" asthma

It has been suggested that asthma almost always as an allergic basis. In this study we tried to determine whether an additional limited skin test panel would be useful in revealing hidden allergies in our "nonallergic" asthmatic patients. In 127 consecutive asthmatic adults, a survey panel of seven tests (rat, mouse, cockroach, Helminthosporium, Chaetomium, Pullularia, and Penicillium) was used in addition to our routine skin test panel (local pollens, Alternaria, Aspergillus, Hormodendrum, dog; and standardized cat, D. pteronyssinus, and D. farinae). On the basis of the routine test panel, 111 patients (87%) were allergic and 16 patients (13%) were nonallergic. Only one nonallergic patient (6%) had any positive survey test results (to cockroach only) while 69 allergic patients (62%) had at least one positive survey test result (p less than .00002). With the possible exception of cockroach, additional skin testing with our survey panel to search for hidden allergies in otherwise nonallergic asthmatic adults is not worthwhile.