SAGB2013 Harriet Moonesinghe (University of Portsmouth)

THE SPECTRUM OF FISH AND SHELLFISH ALLERGIES

Harriet Moonesinghe

PhD Research Student

[email protected]

OVERVIEW

OVERVIEW

o Epidemiology and Prevalence

OVERVIEW


o Cross-reactivity

OVERVIEW


o Cross-reactivity

o Symptoms

OVERVIEW


o Cross-reactivity

o Symptoms

o Differential Diagnosis

OVERVIEW


o Cross-reactivity

o Symptoms


o Management

OVERVIEW


o Cross-reactivity

o Symptoms


o Management

o Introduction of Seafood into the Infant Diet

OVERVIEW


o Cross-reactivity

o Symptoms


o Management

o Introduction of Seafood into the Infant Diet

o PhD Research Project

European Academy of Allergy and Clinical Immunology

Food Hypersensitivity

Food Allergy

IgE mediated food allergy

Non-IgEmediated food

allergy

Non-allergic FHS

10

Immune system

involved

Does not involve immune system

EPIDEMIOLOGY

EPIDEMIOLOGY

• Seafood allergies are caused by the bodies immune response to proteins found in seafood.

EPIDEMIOLOGY


• Seafood allergies are distinct from adverse reactions due to toxins or infectious contaminants, which are not immune-based.

EPIDEMIOLOGY



• Fish and crustacean allergy is more common than mollusc.

EPIDEMIOLOGY




• Seafood allergy is more common in adults than children.

EPIDEMIOLOGY




• Seafood allergy is more common in adults than children.

• The types of seafood causing a reaction varies depending on the local diet.

EPIDEMIOLOGY CONT

EPIDEMIOLOGY CONT

• The prevalence of seafood allergy varies worldwide.

EPIDEMIOLOGY CONT


• 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)

EPIDEMIOLOGY CONT



• In Canada, self-reported rates of fish and crustacean allergy in adults are 0.6% and 1.9 % (Ben-Shoshan, 2010)

EPIDEMIOLOGY CONT




• In South-East Asia the prevalence of fish allergy is higher, at 1.1% (Connett, 2012)

EPIDEMIOLOGY CONT





• 0.5% prevalence rate of Mollusc allergy in Portugal (Falcao, 2004)

EPIDEMIOLOGY CONT





• 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)

CROSS REACTIVITY OF ALLERGENS


• Grass: wheat


• Grass: wheat

• Birch pollen: apple, carrot, celery, pear, tomato, cherry, tree nuts


• Grass: wheat


• Latex: bananas, avocado, chestnut, apple, kiwi, potato, tomato, melon, papaya.


• Grass: wheat


• Latex: bananas, avocado, chestnut, apple, kiwi, potato, tomato, melon, papaya.

Peanut: lupine, other legumes

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).




• 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).

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)

SYMPTOMS

SYMPTOMS

• Seafood allergy is associated with immediate symptoms related to an IgE-mediated food hypersensitivity.

SYMPTOMS


• Fish: vomitting; Mollusc: gastro-intestinal symptoms with a delay in onset; Crustacean: oral symptoms of swelling and itching.

SYMPTOMS



• Seafood is often involved in the most severe food allergic reactions.

SYMPTOMS



• Seafood is often involved in the most severe food allergic reactions.

• Food-dependent exercise induced anaphylaxis to seafood.

SYMPTOMS CONT.

SYMPTOMS CONT.

Non IgE-mediated food allergies include:

SYMPTOMS CONT.

Food protein-induced enterocolitis in children


SYMPTOMS CONT.


Enterocolitis-like reaction in adults

children


SYMPTOMS CONT.



Contact dermatitis in those with occupational and household skin exposure


SYMPTOMS CONT.



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


DIFFERENTIAL DIAGNOSIS


• Anisakis simplex allergy



• Diarrhetic shellfish poisoning (DSP)



• 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

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




• Fish: cross-contamination, wine & beer

• Crustacean: cross-contamination, cooking vapours

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).



• 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.

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.



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.

CONCLUSIONS

CONCLUSIONS

Further prevalence research needed to identify global patterns of allergy.

CONCLUSIONS


Key allergenic proteins in seafood identified as Parvalbumin and Tropmyosin

CONCLUSIONS



Symptoms of allergic reactions as well as non-allergic reactions described.

CONCLUSIONS




Currently the only effective management is avoidance and treatment of adverse symptoms.

CONCLUSIONS





Further clarification is needed on the impact of early introduction of foods and the impact on the childs allergic march.

CONCLUSIONS





Further clarification is needed on the impact of early introduction of foods and the impact on the childs allergic march.

MANY THANKS

SAGB2013 Harriet Moonesinghe (University of Portsmouth)

Health & Medicine

Transcript of SAGB2013 Harriet Moonesinghe (University of Portsmouth)