[Housedust mites: their importance in the pathogenesis of respiratory allergic diseases in Piedmont].

In this study we have considered the importance of house dust mites (Dermatophagoides farinae and pteronyssinus) in the pathogenesis of respiratory allergic diseases in Piedmont. We have identified, from 1980 to 1986, 1530 subjects with sensitization to at least one of the tested allergens; 479 of these (31.3%) were allergic to both or to one of the tested mites. Particularly 97 subjects (6.3%) were sensitized to Dermatophagoides farinae, 73 (4.8%) to Dermatophagoides pteronyssinus and 309 (20.2%) to both of them. This group included 258 males (53.9%) and 221 females (46.1%). Most of the examined subjects had shown the clinical symptoms before the 35th year of age (366 subjects, 76.4%). The mean age of beginning of clinical picture has come out to be of 27.377 +/- 11.527 SD year old. This result shows no significant differences with the mean age come out in allergic subjects to other allergens (26.939 +/- 10.755 SD); 196 subjects (40.9%) presented rhinitis-conjunctivitis, while 102 subjects presented bronchial asthma-rhinitis-conjunctivitis. We have found that bronchial asthma (alone or with other symptoms) was present in 186 subjects (38.8%), while in the allergic subjects sensitized to other allergens was present only in 299 out of 1051 (28.4%); 277 subjects had continuous symptoms (57.8%) while 202 subjects (42.2%) had symptoms only in some periods of the year.