Urinary LTE4 and 9 alpha 11 beta PGF2 in exercise induced asthma

In this paper we assessed, the role of PGD2 and Leukotrienes in the pathoge nesis of exercise-induced asthma (EIA) by measuring their urinary metabolit es. We enrolled 5 healthy children and 24 asthmatic children who performed an exercise test consisting in a 6 minutes free running. The test was consi dered positive if VEF1s drop greater than or equal to 15% in relation to ba seline: 12 patients had a positive test (EIA+), the remaining 12 patients a nd the 5 healthy subjects had negative tests (EIA-). Urinary LTE4 and 9 alp ha 11 beta PGF2 were measured by enzyme-immunoassays and results were expre ssed as pg mediator / ug.creatinine. Although post-exercise levels of both mediators increased, only LTE4 levels were significantly increased in patients with EIA. We conclude that LTE4 i s more related to EIA while 9 alpha 11 beta PGF2 may reflect mast cell acti vation.