Orange roughy is a food which may result in allergy symptoms in sensitised individuals.

Orange Roughy Allergy Test: Allergen Exposure

The orange roughy is a large, deep sea fish of the family Trachichthyidae (known as the slimehead family). It is found in the western Pacific Ocean, eastern Atlantic Ocean, the Indo-Pacific waters off New Zealand and Australia, and the eastern Pacific off the coast of Chile.

The flesh of the orange roughy is described as firm in texture, with a mild flavour. It is generally sold skinned and filleted, either fresh or frozen. The largest consumers of this fish are the United States and China. Major exporters include New Zealand, China, Peru and Indonesia.

Due to overfishing, stocks of orange roughy have declined, and in 2010, Greenpeace International added orange roughy to its seafood red list, indicating fish which are usually sourced from unsustainable fisheries.

Orange roughy is very low in saturated fat, and is also a very good source of protein and selenium, although relatively high in cholesterol. It is usually served pan-fried, baked or poached, and features in a number of regional cuisines, including Cajun, Thai and Chinese. It can also be found in curries, fish stews, pies and salads.

Orange Roughy Allergy Test: Allergen Description

No specific allergens present in orange roughy have been characterised to date, although a number of proteins have been identified.

Orange Roughy 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 orange roughy within the order Trachichthyiformes can therefore be expected, which includes roughies and slimeheads.

Orange Roughy Allergy Test: Clinical Experience

Sensitisation to fish allergen is common. Fish, including orange roughy, 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.

Orange roughy can contain elevated amounts of mercury, and it is advised to restrict consumption to no more than 2 servings per week (adults) or 1 serving per week (children).

Acute anisakiasis as a result of the larvae of the fish parasite Anisakis simplex may occur following ingestion of undercooked or raw chub mackerel.

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.