Up to 41% of fish-allergic patients may tolerate at least one
bony fish based on the absence of PV-sIgE
To investigate possibly tolerated fish species based on the absence of
PV-sIgE, we first determined the percentage of the patients negative to
each investigated PV in each analyzed country (Figure 3A ). IgE
of 78% of patients in total did not recognize ray PV, with the highest
proportion of such patients in Luxembourg (97%) and the lowest in Spain
(64%). 25% of patients were negative to sole PV (highest proportion in
Luxembourg, 41%), while 19% in total and up to 38% (China) were
negative to cod PV. To investigate how to best identify the absence of
IgE to PV from specific species, the probability of an IgE test to be
negative for a specific PV, when already negative for another specific
PV, was calculated (Figure 3B ). Among the beta-PVs, tuna,
mackerel and carp appeared as the best predictors of highly probable
negative IgE tests for other beta PVs. For example, if negative for tuna
PV, a probability of ≥90% exists for an IgE test to be negative for any
other tested PV, except for salmon (71%). These findings should be
considered when designing a panel of species for tolerance-confirming
FC.