Prevalence of patent and latent atopy among a general normal adult population in the south east of France by RAST investigation and correlation with circulating total IgE levels.

A population of 512 adults (men: 266, 52%, women: 246, 48%) with mean age 41.4 years (S.D. 10.7) was investigated. This population was subdivided into five groups: Marseilles city, Manosque a small town in a prealpine area, the area surrounding the Etang de Berre, a rural area in Northern Bouches du Rhône and Chateaurenard, a small town in an intensive agricultural area. RASTs to a panel of eight allergens (Lolium perenne, Parietaria officinalis, Cupressus sempervirens, Olea europea, Cat dander, Alternaria tenuis, Dermatophagoides pteronyssinus, and Castor bean seed) were done. 99 subjects were found to have a RAST positive to one or several allergens. The main positives found by RAST were a grass pollen (Lolium perenne) and the mite Dermatophagoides pteronyssinus with respectively 10.1% and 11.3% of the results followed by the pollens of Olea Europea 4.4%, Parietaria officinalis 3.1% and Cupressus sempervirens 1.9%, Castor bean seed 1.7% Cat dander 0.9% and Alternaria tenuis 0.9%. Allergy to cstor bean (Ricinus communis) seed was found mostly in the Chateaurenard area where castor castor bean pomace is used in the fields as a fertilizer. There is an almost equal number of RAST positivities to mites (13.3%) than to pollens (11.1%). The prevalence of RAST positive was higher in men (24.1%) than in women (14.2%), p < 0.01). This prevalence is lower when age is increasing. Thirty four subjects (6.6%) had clinical symptoms: This group has a higher prevalence of positive RAST in cases of allergic rhinitis (p < 0.01) and of asthma (p > 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)