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

Catfish Allergy Test: Allergen Exposure

Catfish have been both caught and farmed by humans for food for hundreds of years. They occur almost worldwide, being found in Africa, Asia, Europe, and North America.

In Central Europe, catfish are a delicacy, and are traditionally eaten on feast days or holidays. This practice was later brought to the United States by migrants from this region, where it persists, particularly in the southern states.

The most popular species of catfish consumed in the United States are the channel catfish and blue catfish, both widely caught and farmed.

Depending on the region, catfish may be prepared in a number of different ways. In Europe it is generally cooked whole in a similar manner to carp. In the US, it is generally coated in breadcrumbs or cornmeal and deep fried. Fried catfish is also a popular street food in Indonesia and Malaysia, served with vegetables and chili paste.

In Hungarian cuisine, catfish is served alongside pasta with cheese curds, and covered with a paprika sauce. In Nigeria, catfish is often cooked in a variety of stews and soups, the most popular being a catfish pepper soup.

Catfish is a seasonal delicacy eaten during monsoons in the Indian states of Odisha, West Bengal and Assam as well as Bangladesh.

Catfish is a good source of vitamin D but has relatively low levels of omega-3 fatty acids. It is also a good source of protein and selenium.

Catfish Allergy Test: Allergen Description

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

Catfish Allergy Test: Potential Cross-Reactivity

Species within groups of fish such as Gadiformes (examples: pollock and cod) and Scombroid fishes (examples: mackerel and tuna) seem to share allergenic components.

Cross-reactivity to catfish within the order Siluriformes can therefore be expected, which includes the Channel catfish, Wels catfish, Blue catfish, Black bullhead, Yellow bullhead and Bayad.

Catfish Allergy Test: Clinical Experience

Sensitisation to fish allergen is common. Fish, including catfish, 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

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

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.