Skin Puncture Test Response Is Not Altered By Season of Testing

Rationale: Serum specific IgE levels to pollens have been reported to change during the season of pollination.  Little information is available as to the effect of season on skin test reactivity.

Methods: We performed a retrospective chart review of all skin tests done in one clinic over 1 year. Positive tests were defined as a wheal of 3mm greater than diluent. Dichotomous variables were analyzed with Fisher’s exact test and continuous variables with Mann-Whitney U test.

Results: We analyzed 769 tests.  Grass percent positivity was the same for grass season versus out of season (50% vs 47%, p=0.38); wheal size of positive tests was not different whether measured during grass season or out of season (7cm vs 7cm, p=0.98).  Tree percent positivity was the same for tree season versus out of season (44% vs 44%, p=1.00); wheal size of positive tests was not different whether measured during grass season or out of season (5cm vs 5cm, p=0.93).  Ragweed percent positivity was the same for ragweed season versus out of season (22% vs 27%, p=0.23); wheal size of positive tests was not different whether measured during ragweed season or out of season (5cm vs 4cm, p=0.24).

Conclusions: There is no significant seasonal variability of pollen sensitization detection rate and wheal size by skin puncture testing.