Recruitment of fish allergic subjects
This study recruited subjects aged 1-18 years with reported history of
IgE-mediated fish allergy from six regional hospitals in Hong Kong (HK;
Prince of Wales Hospital, Queen Mary Hospital, Queen Elizabeth Hospital,
Yan Chai Hospital, Princess Margaret Hospital and United Christian
Hospital) and Sagamihara National Hospital in Kanagawa, Japan. The
inclusion criteria include (1) subjects with convincing history of
immediate fish allergy as defined by immediate allergic symptoms within
2 hours following fish ingestion within two years before recruitment and
clinically diagnosed by an allergy specialist; and (2) subjects with
evidence of IgE sensitization to fish by blood sIgE measurement against
cod (f3), salmon (f41), tuna (f40) and/or grass carp (experimental
ImmunoCAP developed in collaboration with Thermo Fisher) and/or SPT with
commercial fish mix extract (ALK-Abelló). Exclusion criteria are
subjects receiving maintenance immunosuppressive treatments that cannot
be stopped for four weeks prior to study and who receive intravenous
immunoglobulin treatment within three months. Severity of allergic
symptoms to fish was calculated based on the Ordinal Food Allergy
Severity Score (oFASS)20. Briefly, Grade 1 includes
reactions restricted to oral cavity. Grade 2 to 5 may include oral
symptoms but with other target organs affected, by which grades 2 and 3
reactions involve skin, eye/nose and/or digestive system. Involvement of
larynx and/or bronchi reactions are graded 4 while grade 5 would involve
cardiovascular and/or nervous systems. Participants and/or their legal
guardians gave written informed consent. Ethical approvals were obtained
from Joint Chinese University of Hong Kong-New Territories East Cluster
Clinical Research Ethics Committee (2019.034 & 2019.612) and the
Sagamihara National Hospital Ethics Committee (2019-003).