Gulf flounder is a food which may result in allergy symptoms in sensitised individuals.

Gulf Flounder Allergy Test: Allergen Exposure

The gulf flounder is a flatfish native to the western Atlantic, northern Bahamas, Gulf of Mexico and from the western Caribbean to Colombia. It is utilised as both a sport fish and as a food fish, and usually caught using nets, hook and line or spearfishing.

Due to overfishing, the populations of many flounder species are now as low as 10% of their pre-industrial era levels. As such, Atlantic flounders and soles are currently on the list of seafood that sustainability-minded consumers should avoid, although there is some evidence that the situation is improving due to careful management of fisheries, alongside farming programs.

Gulf flounder is sold fresh or frozen, either as whole fish or fillets. The flesh is described as mild and sweet in flavour. Broiled gulf flounder, often stuffed with crabmeat, is one of the classic seafood dishes of the northern Gulf coast. Flounders are also served fried, baked, sauteed, and raw (as sashimi).

As gulf flounder is delicate in flavour, it is generally served on it’s own, and cooked with minimal additional ingredients, such as lemon, butter or white wine as well as salt and pepper.

Flounder is the main ingredient in the French dish Flounder Meunière, cooked with browned butter, fresh lemon and parsley.

Flounder is very low in fat and contains no carbohydrates. It is an excellent source of protein, as well as containing a range of vitamins and minerals, such as vitamin C, iron and calcium although mostly in small amounts. Some flounder may contain high levels of sodium, with a 225g portion supplying up to a third of an adults recommended daily maximum.

Gulf Flounder Allergy Test: Allergen Description

No specific allergens present in gulf flounder have been characterised, although a number of proteins have been identified.

Gulf Flounder 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 gulf flounder within the order Pleuronectiformes can therefore be expected, which includes flounders, soles, turbot, plaice, and halibut.

Gulf Flounder Allergy Test: Clinical Experience

Sensitisation to fish allergen is common. Fish, including gulf flounder, 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.

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

Fish allergy is sometimes confused with a reaction to histamine in spoiled fish.