SEQUENTIAL DETERMINATIONS OF DERMATOPHAGOIDES SPP ALLERGENS IN A TROPICAL CITY

The purpose of this study was to establish seasonal levels of Der p 1, Der f 1 and D. pteronyssinus allergens in mattress and floor dust sam ples in the homes of 20 mite-allergic asthmatic patients in Cartagena, Colombia. Dust samples were collected using a portable vacuum cleaner once monthly for the same 12 months in all houses. The highest Der p 1 levels in mattress samples were defected in August (geometric mean = 109.49 ng/g) and represented a 22-times increase from the lowest leve l observed in November. Der f 1 was detected in only 3 mattresses rang ing from 90 ng to 1.6 mu g per gram of dust. The highest levels were d etected in February and March. The highest level of D. pteronyssin us allergens in mattress dust samples, quantitated by RAST-inhibition, wa s 8, 994 A U/g (80% inhibition); the lowest level detected was 150 AU/ g (5% inhibition). Allergen levels were significantly higher in mattre sses than in floor samples (p < 0.001). Overall, a Spearman rank corre lation coefficient of 0.48, p < 0.001, was obtained between Der p 1 an d D. pteronyssinus allergens. There was a good correlation between mit e allergens and absolute humidity (r = 0.8, p = 0.007). Der p 1, Der f 1 and D. pteronyssinus allergen levels show minimal variations in thi s tropical environment. Allergens derived from various mite species mu st be considered when assessing mite allergen exposure in these enviro nments.