Description
Megrim Allergy Test
Code: f311
Latin name: Lepidorhombus whiffiagonis
Source material: Whole fish
Family: Bothidae
Common names: Megrim sole, White sole, Whiff, Cornish sole
Megrim is a food which may result in allergy symptoms in sensitised individuals.
Megrim Allergy Test: Allergen Exposure
Megrim is a species of flatfish native to the northeast Atlantic and Mediterranean Sea. It is caught commercially as a food fish in some European countries, usually by bottom trawling.
The largest consumers of megrim are France and Spain, although the availability of this fish in the United Kingdom is increasing as stocks of other commonly consumed species such as cod or haddock are reduced by overfishing. In the U.K. it may be known as megrim sole or Cornish sole, and is used as a substitute or replacement for Dover sole or lemon sole in many recipes.
Megrim is usually sold fresh or frozen, and can be prepared in a variety of ways, including grilling, baking, frying and poaching. It may also be added to fish pie, fishcakes, chowder, salads or soups, as well as other processed fish products.
It is a very good source of protein, and also of vitamin D, niacin, vitamin B6, phosphorus and potassium, and a very good source of vitamin B12 and selenium.
Megrim Allergy Test: Allergen Description
No specific allergens present in megrim have been characterised to date, although a number of proteins have been identified.
Megrim Allergy Test: Potential Cross-Reactivity
Species within groups of fish, like Gadiformes (examples: codfish and hake) and Scombroid fishes (examples: mackerel and tuna) seem to share allergenic components. The overlap of allergen specificity between the groups seems to be moderate or even small.
Cross-reactivity to megrim within the order Pleuronectiformes can therefore be expected, which includes halibut, flounders, soles, turbot, and plaice.
Megrim Allergy Test: Clinical Experience
Sensitisation to fish allergen is common. Fish, including megrim, is a potential cause of food allergy and atopic dermatitis.
Immediate allergic reactions may follow ingestion of even minute amounts of fish.
Symptoms can include oral allergy syndrome, generalised urticaria, facial angioedema and anaphylaxis. In a study of a group of megrim-allergic children, the clinical symptoms induced by this allergy were urticaria and angioedema (92.4%) in 79 patients, followed by atopic dermatitis (17.7%) and inhalation-related asthma (13.9%).
Because patients react to both cooked and raw fish, it is assumed the allergens are heat-resistant. However, more recent studies indicate that patients may react differently to processed food and that allergic reactions may be species-specific.
It has been reported that some fish allergic persons can exhibit allergic symptoms due to the steam (airborne allergens) from cooking fish.
Other reactions
Anisakiasis, or herring worm disease, is a parasitic disease caused by nematodes (worms) that attach to the wall of the esophagus, stomach, or intestine of the megrim.
Symptoms can include abdominal pain, nausea, vomiting, abdominal distention, diarrhea, blood and mucus in stool, and mild fever. Allergic reactions with rash and itching, and infrequently, anaphylaxis, can also occur.
Fish allergy is sometimes confused with a reaction to histamine in spoiled fish.