Skin Prick Test
In an attempt to assess IgE binding in vivo , peanut-allergic
subjects and non-allergic healthy controls were skin prick tested (SPT)
with a panel of protein extracts created from raw, roasted and
autoclaved peanuts and the resulting wheal diameters were measured
(Table 1). Within the peanut-allergic group, a statistically significant
reduction in mean wheal diameter was observed using the autoclaved
extract when compared to raw (p < 0.05).
Additional information was revealed when the allergic group was further
stratified into two groups: one group of patients who have previously
experienced anaphylaxis to peanut or have demonstrated high likelihood
of it based on past clinical tests, and the second group of patients
known to experience only oral symptoms upon peanut consumption. A
striking decrease in wheal size was observed when using autoclaved
extracts compared to raw in the group that experiences oral symptoms. In
contrast, this was not observed in the case of the group at risk for
anaphylaxis. The roasted peanut extract showed a slight decrease in
wheal size in the group at risk for anaphylaxis and an increase in the
group of patients who experience oral symptoms.