NEW YORK, Dec 17 (Reuters Health) -- People who are allergic to milk may
also be allergic to pre-packed salmon, Dutch investigators are cautioning in a
letter published in the December 18/25th issue of The Lancet.
The type of salmon implicated in the allergic reaction is vacuum-packed,
"restructured" fish, where smaller pieces of fish have been bound together using
the binding protein casein. This protein is also found in milk, hence the
potential risk to individuals with milk allergy.
The report does not implicate canned salmon as an allergy risk for these
individuals.
Dr. Stef Koppelman and colleagues from the University Medical Centre of
Utrecht, the Netherlands, describe a 30-year-old woman who had a number of
allergies including allergies to milk. Within one hour of eating salmon bought
at the supermarket, she developed itchy ears, severe swelling in the face,
nausea and stomach pain. "She had never before experienced an adverse reaction
to salmon or any other kind of fish," the investigators note.
Although she treated herself with several anti-allergy medications at
home, symptoms did not disappear and she had to go to the local emergency
department, where she was treated with steroids. On testing a sample of the same
salmon that had caused the patient's reaction, the researchers detected small
amounts of casein in the salmon, which was not found in fresh salmon that they
also tested. Manufacturers have recently started using casein to restructure
meat and fish products.
In eating the salmon, the patient would have consumed only a small amount
of casein, but that small amount is "capable of inducing an allergic reaction in
allergic patients," the authors indicate. Koppelman commented that this case
"illustrates the importance of proper ingredient labeling, especially when food
allergens are involved."
He also noted that manufacturers do have an alternative to casein that
they could use in the processing of food and thus avoid "unexpected allergic
reactions."
