8. OVERVIEW
o Epidemiology and Prevalence
o Cross-reactivity
o Symptoms
o Differential Diagnosis
o Management
o Introduction of Seafood into the Infant Diet
9. OVERVIEW
o Epidemiology and Prevalence
o Cross-reactivity
o Symptoms
o Differential Diagnosis
o Management
o Introduction of Seafood into the Infant Diet
o PhD Research Project
10. European Academy of Allergy and Clinical Immunology
Food
Hypersensitivity
Food Allergy
IgE mediated
food allergy
Non-IgE
mediated food
allergy
Non-allergic
FHS
1
0
Immune
system
involved
Does not
involve
immune
system
14. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
15. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
• Fish and crustacean allergy is more common than
mollusc.
16. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
• Fish and crustacean allergy is more common than
mollusc.
• Seafood allergy is more common in adults than children.
17. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
• Fish and crustacean allergy is more common than
mollusc.
• Seafood allergy is more common in adults than children.
• The types of seafood causing a reaction varies
depending on the local diet.
18. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
• Fish and crustacean allergy is more common than
mollusc.
• Seafood allergy is more common in adults than children.
• The types of seafood causing a reaction varies
depending on the local diet.
19. EPIDEMIOLOGY
• Seafood allergies are caused by the bodies immune
response to proteins found in seafood.
• Seafood allergies are distinct from adverse reactions
due to toxins or infectious contaminants, which are not
immune-based.
• Fish and crustacean allergy is more common than
mollusc.
• Seafood allergy is more common in adults than children.
• The types of seafood causing a reaction varies
depending on the local diet.
22. EPIDEMIOLOGY CONT
• The prevalence of seafood allergy varies worldwide.
• A UK birth cohort looking at 11 and 15 year olds
showed 0.9-1.8% for fish and 0.3-0.7% for shellfish
allergy (Pereira et al, 2005)
23. EPIDEMIOLOGY CONT
• The prevalence of seafood allergy varies worldwide.
• A UK birth cohort looking at 11 and 15 year olds
showed 0.9-1.8% for fish and 0.3-0.7% for shellfish
allergy (Pereira et al, 2005)
• In Canada, self-reported rates of fish and crustacean
allergy in adults are 0.6% and 1.9 % (Ben-Shoshan,
2010)
24. EPIDEMIOLOGY CONT
• The prevalence of seafood allergy varies worldwide.
• A UK birth cohort looking at 11 and 15 year olds
showed 0.9-1.8% for fish and 0.3-0.7% for shellfish
allergy (Pereira et al, 2005)
• In Canada, self-reported rates of fish and crustacean
allergy in adults are 0.6% and 1.9 % (Ben-Shoshan,
2010)
• In South-East Asia the prevalence of fish allergy is
higher, at 1.1% (Connett, 2012)
25. EPIDEMIOLOGY CONT
• The prevalence of seafood allergy varies worldwide.
• A UK birth cohort looking at 11 and 15 year olds
showed 0.9-1.8% for fish and 0.3-0.7% for shellfish
allergy (Pereira et al, 2005)
• In Canada, self-reported rates of fish and crustacean
allergy in adults are 0.6% and 1.9 % (Ben-Shoshan,
2010)
• In South-East Asia the prevalence of fish allergy is
higher, at 1.1% (Connett, 2012)
• 0.5% prevalence rate of Mollusc allergy in Portugal
(Falcao, 2004)
26. EPIDEMIOLOGY CONT
• The prevalence of seafood allergy varies worldwide.
• A UK birth cohort looking at 11 and 15 year olds
showed 0.9-1.8% for fish and 0.3-0.7% for shellfish
allergy (Pereira et al, 2005)
• In Canada, self-reported rates of fish and crustacean
allergy in adults are 0.6% and 1.9 % (Ben-Shoshan,
2010)
• In South-East Asia the prevalence of fish allergy is
higher, at 1.1% (Connett, 2012)
• 0.5% prevalence rate of Mollusc allergy in Portugal
(Falcao, 2004)
• It has been suggested that allergic reactions to fish are
common in countries where fish constitutes a major
source of protein in the diet (Chiang et al, 2007)
33. CROSS-REACTIVITY IN SEAFOOD
• Fish: Parvalbumin is the dominant allergen in finned
fish, distributed universally in the white muscle of fish.
34. CROSS-REACTIVITY IN SEAFOOD
• Fish: Parvalbumin is the dominant allergen in finned
fish, distributed universally in the white muscle of fish.
• Crustacean: Tropmyosin, higher homologies of up to
98% across species.
35. CROSS-REACTIVITY IN SEAFOOD
• Fish: Parvalbumin is the dominant allergen in finned
fish, distributed universally in the white muscle of fish.
• Crustacean: Tropmyosin, higher homologies of up to
98% across species.
• NO cross-reaction between fish allergens and shellfish
allergens have to date been demonstrated (Lopata &
Lehrer, 2009).
36. CROSS-REACTIVITY IN SEAFOOD
• Fish: Parvalbumin is the dominant allergen in finned
fish, distributed universally in the white muscle of fish.
• Crustacean: Tropmyosin, higher homologies of up to
98% across species.
• NO cross-reaction between fish allergens and shellfish
allergens have to date been demonstrated (Lopata &
Lehrer, 2009).
• However 21-43% of fish-allergic individuals are also
allergic to shellfish (Venter & Arshad, 2011).
37. SEAFOOD CROSS-REACTING SPECIES
COD TUNA, MACKEREL, HERRING, PLAICE, SOLE,
BASS, EEL
TUNA COD, TROUT, SALMON
SALMON SARDINE, MACKEREL, TUNA
MACKEREL ANCHOVY, COD, SALMON, HERRING, SARDINE,
PLAICE
PRAWNS LOBSTER, CRAB, CRAYFISH
MUSSELS OCTOPUS, SQUID
SHELLFISH COCKROACH, HOUSE DUST MITE, SNAILS
Cross reactivity of fish and shellfish (Skypala & Venter, 2009)
39. SYMPTOMS
• Seafood allergy is associated with immediate symptoms
related to an IgE-mediated food hypersensitivity.
40. SYMPTOMS
• Seafood allergy is associated with immediate symptoms
related to an IgE-mediated food hypersensitivity.
• Fish: vomitting; Mollusc: gastro-intestinal symptoms
with a delay in onset; Crustacean: oral symptoms of
swelling and itching.
41. SYMPTOMS
• Seafood allergy is associated with immediate symptoms
related to an IgE-mediated food hypersensitivity.
• Fish: vomitting; Mollusc: gastro-intestinal symptoms
with a delay in onset; Crustacean: oral symptoms of
swelling and itching.
• Seafood is often involved in the most severe food
allergic reactions.
42. SYMPTOMS
• Seafood allergy is associated with immediate symptoms
related to an IgE-mediated food hypersensitivity.
• Fish: vomitting; Mollusc: gastro-intestinal symptoms
with a delay in onset; Crustacean: oral symptoms of
swelling and itching.
• Seafood is often involved in the most severe food
allergic reactions.
• Food-dependent exercise induced anaphylaxis to
seafood.
43. SYMPTOMS
• Seafood allergy is associated with immediate symptoms
related to an IgE-mediated food hypersensitivity.
• Fish: vomitting; Mollusc: gastro-intestinal symptoms
with a delay in onset; Crustacean: oral symptoms of
swelling and itching.
• Seafood is often involved in the most severe food
allergic reactions.
• Food-dependent exercise induced anaphylaxis to
seafood.
46. SYMPTOMS CONT.
Food protein-induced enterocolitis in children
Non IgE-mediated food allergies include:
47. SYMPTOMS CONT.
Food protein-induced enterocolitis in children
Enterocolitis-like reaction in adults
children
Non IgE-mediated food allergies include:
48. SYMPTOMS CONT.
Food protein-induced enterocolitis in children
Enterocolitis-like reaction in adults
Contact dermatitis in those with occupational and
household skin exposure
Non IgE-mediated food allergies include:
49. SYMPTOMS CONT.
Food protein-induced enterocolitis in children
Enterocolitis-like reaction in adults
Contact dermatitis in those with occupational and
household skin exposure
Occupational allergies i.e. asthma and dermatitis in
workers exposed to crustaceans, molluscs and bony fish
Non IgE-mediated food allergies include:
50. SYMPTOMS CONT.
Food protein-induced enterocolitis in children
Enterocolitis-like reaction in adults
Contact dermatitis in those with occupational and
household skin exposure
Occupational allergies i.e. asthma and dermatitis in
workers exposed to crustaceans, molluscs and bony fish
Non IgE-mediated food allergies include:
54. DIFFERENTIAL DIAGNOSIS
• Anisakis simplex allergy
• Diarrhetic shellfish poisoning (DSP)
• Scombroid poisoning easily confused with fish allergy
due to the typical symptoms which include: flushing,
sweating, urticaria, gastrointestinal symptoms,
palpitations and in severe cases bronchospasm
56. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
57. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
• Fish, crustacean and mollusc are all required by EU
labelling laws to be declared on all products, however
some products considered to be a very low risk for
reactions do not have to.
58. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
• Fish, crustacean and mollusc are all required by EU
labelling laws to be declared on all products, however
some products considered to be a very low risk for
reactions do not have to.
• Fish: cross-contamination, wine & beer
59. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
• Fish, crustacean and mollusc are all required by EU
labelling laws to be declared on all products, however
some products considered to be a very low risk for
reactions do not have to.
• Fish: cross-contamination, wine & beer
• Crustacean: cross-contamination, cooking vapours
60. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
• Fish, crustacean and mollusc are all required by EU
labelling laws to be declared on all products, however
some products considered to be a very low risk for
reactions do not have to.
• Fish: cross-contamination, wine & beer
• Crustacean: cross-contamination, cooking vapours
61. MANAGEMENT OF SEAFOOD ALLERGY
• Unlike some food allergies, seafood allergy does not in
general resolve with age and therefore correct life-long
dietary avoidance is essential (Lopata & Lehrer, 2009).
• Fish, crustacean and mollusc are all required by EU
labelling laws to be declared on all products, however
some products considered to be a very low risk for
reactions do not have to.
• Fish: cross-contamination, wine & beer
• Crustacean: cross-contamination, cooking vapours
64. INTRODUCTION OF SEAFOOD INTO
THE INFANT DIET
• ‘window of tolerance’
• The AAP recommended no solids be given to an infant
until the age of 6months, with a further delay in the
introduction of known allergens (cows milk until 1, hens
eggs until 2 and peanuts, tree nuts and fish until
3years).
65. INTRODUCTION OF SEAFOOD INTO
THE INFANT DIET
• ‘window of tolerance’
• The AAP recommended no solids be given to an infant
until the age of 6months, with a further delay in the
introduction of known allergens (cows milk until 1, hens
eggs until 2 and peanuts, tree nuts and fish until
3years).
• However these recommendations have now been
revised based on the lack of empirical evidence of the
effectiveness in preventing food allergy, and it is no
longer advised to delay the introduction of allergenic
foods beyond 4-6months.
67. MY PHD RESEARCH PROJECT
1. To determine the prevalence and natural history of fish
and shellfish allergy in different regions of the world.
68. MY PHD RESEARCH PROJECT
1. To determine the prevalence and natural history of fish
and shellfish allergy in different regions of the world.
2. To characterise fish allergic adults in the UK with
regards to the types of fish involved and other co-
existing allergies such as crustacean and molluscs, as
well as the presence of atopic disease and their health-
related quality of life.
69. MY PHD RESEARCH PROJECT
1. To determine the prevalence and natural history of fish
and shellfish allergy in different regions of the world.
2. To characterise fish allergic adults in the UK with
regards to the types of fish involved and other co-
existing allergies such as crustacean and molluscs, as
well as the presence of atopic disease and their health-
related quality of life.
3. To correlate fish intake in pregnancy, the timing of
introduction of fish in the first 3 years of life, and
frequency of fish consumption with the development of
fish allergy and other allergic diseases in the first 10
years of life.
72. CONCLUSIONS
Further prevalence research needed to identify global
patterns of allergy.
Key allergenic proteins in seafood identified as
Parvalbumin and Tropmyosin
73. CONCLUSIONS
Further prevalence research needed to identify global
patterns of allergy.
Key allergenic proteins in seafood identified as
Parvalbumin and Tropmyosin
Symptoms of allergic reactions as well as non-allergic
reactions described.
74. CONCLUSIONS
Further prevalence research needed to identify global
patterns of allergy.
Key allergenic proteins in seafood identified as
Parvalbumin and Tropmyosin
Symptoms of allergic reactions as well as non-allergic
reactions described.
Currently the only effective management is avoidance
and treatment of adverse symptoms.
75. CONCLUSIONS
Further prevalence research needed to identify global
patterns of allergy.
Key allergenic proteins in seafood identified as
Parvalbumin and Tropmyosin
Symptoms of allergic reactions as well as non-allergic
reactions described.
Currently the only effective management is avoidance
and treatment of adverse symptoms.
Further clarification is needed on the impact of early
introduction of foods and the impact on the childs
allergic march.
76. CONCLUSIONS
Further prevalence research needed to identify global
patterns of allergy.
Key allergenic proteins in seafood identified as
Parvalbumin and Tropmyosin
Symptoms of allergic reactions as well as non-allergic
reactions described.
Currently the only effective management is avoidance
and treatment of adverse symptoms.
Further clarification is needed on the impact of early
introduction of foods and the impact on the childs
allergic march.
MANY THANKS
