We report a case of jellyfish allergy diagnosed via an oral food challenge. A 14-year-old boy had no history of jellyfish stings and had been eating commercially available jellyfish products twice yearly for the past 5-6 years. Five minutes after eating a commercially available boiled jellyfish product (100g), he experienced nausea, wheezing, and erythema and had visited our hospital. We suspected an anaphylactic reaction and treated him with intramuscular adrenaline injection, corticosteroid and antihistamine infusions, volume resuscitation, and salbutamol sulfate inhalation, which resulted in an improvement of the symptoms. One-month later in our hospital, we administered an oral food challenge of the same boiled jellyfish product bought at the same grocery store to the patient. After ingesting 14g of boiled jellyfish, he experienced erythema, wheezing, nausea, and abdominal pain. Several reports have described anaphylaxis caused by the ingestion of jellyfish, but the allergens in jellyfish have not been analyzed. A skin prick test for poly-gamma-glutamic acid (PGA) which is a component of jellyfish stings was negative. This suggests that he was sensitized to some allergen other than PGA via a route different from that of jellyfish sting. Our skin prick test for several kinds of edible jellyfish suggests that allergenicity may be different for different jellyfish.
Keywords: anaphylaxis; jellyfish; oral food challenge; poly-gamma-glutamic acid; prick to prick test.