Atlantic cod allergy

Atlantic Cod Allergy: A Serious Food Allergy

The Atlantic cod allergy, also known as Gadus morhua fish allergy, is a type of food allergy triggered by the consumption of Atlantic cod (Gadus morhua). This allergy can cause a range of symptoms, from mild to severe, and requires immediate medical attention in some cases.

Symptoms of Atlantic Cod Allergy

The symptoms of an Atlantic cod allergy can include:

• Abdominal pain
• Nausea and vomiting
• Diarrhea
• Blood and mucus in stool
• Mild fever
• Rash or hives
• Tingling sensation near or around the mouth
• Swelling
• Abdominal discomfort
• Itching or hives
• Congestion
• Difficulty breathing

Prevalence of Atlantic Cod Allergy

The prevalence of fish allergy, including Atlantic cod allergy, varies across different countries and regions. According to some studies, the prevalence of fish allergy is relatively low, ranging from 0.01% in Israel to 0.3-0.6% in children in the US.

Importance of Accurate Diagnosis

Accurate diagnosis of an Atlantic cod allergy is crucial to prevent severe reactions and ensure proper treatment. Skin or blood tests alone may not be sufficient to identify which fish varieties will cause a reaction, and oral food challenges may be necessary to confirm the allergy.

References:

• [4] Gad m 1 is the major allergen from Atlantic cod.
• [5] Atlantic cod allergy (DOID:0060514) Alliance: disease page. Synonyms: Gadus morhua fish allergy.
• [6] Definition: A fish allergy triggered by Gadus morhua.
• [10] A more recent study of 35 children with allergy to cod, salmon or mackerel found that almost one-third could tolerate at least one of the three types of fish during an oral food challenge.

Symptoms of an Atlantic Cod Allergy

An allergic reaction to Atlantic cod can manifest in various ways, depending on the individual's sensitivity level. Here are some common signs and symptoms:

• Oropharyngeal itching and swelling: This is often the first symptom, occurring shortly after consuming fresh raw cod.
• Hives, itching, or redness on the skin: These skin symptoms can appear anywhere on the body, including the face, lips, tongue, or throat.
• Swelling of the face, lips, tongue, or throat: This swelling can make it difficult to breathe or swallow.
• Nasal congestion or runny nose: Some individuals may experience respiratory symptoms as a result of an allergic reaction.
• Abdominal pain, nausea, and vomiting: Gastrointestinal symptoms can also occur in response to consuming Atlantic cod.

Severe Symptoms

In severe cases, an allergic reaction to Atlantic cod can lead to:

• Anaphylaxis: A life-threatening condition characterized by rapid heartbeat, low blood pressure, and difficulty breathing.
• Angioedema: Swelling of the skin and mucous membranes that can cause respiratory distress.

Important Notes

It's essential to note that spoiled fish can elicit similar symptoms, but they are not necessarily an allergic reaction. If you suspect a food allergy or experience severe symptoms after consuming Atlantic cod, seek medical attention immediately.

References:

• [1] Oropharyngeal itching and swelling occur as the first symptom, always preceding the onset of any accompanying symptoms.
• [2] Hives, itching, or redness on the skin; Swelling of the face, lips, tongue, or throat; Nasal congestion or runny nose are common signs and symptoms of an Atlantic cod allergy.
• [4] Ingestion of salmon by sensitized individuals triggers allergic symptoms such as oral allergy syndrome, angioedema, urticaria, anaphylaxis, nausea, and vomiting. (Note: While the context mentions "salmon," the symptoms are similar to those experienced with Atlantic cod.)
• [5] Signs or symptoms of anaphylaxis may include: Rapid or increased heart rate; Swollen throat or lump making it difficult to breathe; Low blood pressure; Extreme fatigue.
• [6] The classic clinical signs include oral allergy syndrome, cutaneous symptoms (diffuse urticaria, angioedema), gastrointestinal manifestations (abdominal pain, nausea, vomiting).
• [7] Spoiled fish can elicit symptoms in every person having eaten it. The reaction is similar to an allergic reaction, i.e., swelling, hives, wheezing etc.
• [8] Fish-allergic symptoms are the same than other IgE-mediated food allergies and can range from mild (e.g., runny nose, headache, skin rashes) to moderate (e.g., abdominal pain, nausea).

Diagnosing Atlantic Cod Allergy

Diagnosing an allergy to Atlantic cod, also known as codfish, involves a combination of clinical assessment and specific tests to detect the presence of IgE antibodies in the blood.

• Clinical History: The first step in diagnosing a cod allergy is to assess the patient's clinical history. This includes asking about symptoms such as hives, itching, swelling, stomach cramps, diarrhea, or difficulty breathing after consuming codfish.
• Skin Prick Test (SPT): A skin prick test can be used to detect IgE antibodies in the blood. In this test, a small amount of cod extract is placed on the skin, and the reaction is observed. A positive result indicates an allergy to codfish [8][9].
• Specific IgE Tests: Specific IgE tests measure the concentration of IgE antibodies in the blood that are specific to codfish. These tests can be used to confirm a diagnosis of a cod allergy [5].
• IgE Blood Test: An IgE blood test measures the levels of IgE antibodies in the blood. This test can help detect an allergy to codfish by measuring the concentration of IgE antibodies specific to codfish [2][3].

Diagnostic Algorithm

The diagnostic algorithm for a cod allergy typically involves the following steps:

1. Clinical assessment and history taking
2. Skin prick test (SPT)
3. Specific IgE tests
4. IgE blood test

A positive result from any of these tests can indicate an allergy to Atlantic codfish.

References

[1] WS Tong, "Current clinical diagnosis of seafood allergy", 2018. [2] Cod Allergy Test: Allergen Description​​ Several IgE-reactive allergens spanning a wide molecular-weight range have been detected in Cod extracts. [3] The IgE Allergy Explorer is a specific IgE test that measures the concentration of IgE antibodies to over 150 food and environmental allergens at the extract level. [4] Detection of allergy is based on clinical history, skin prick test, specific IgE tests, histamine release test, and immunoblotting, followed by oral fish challenge. [5] An indication for IgE-mediated fish allergy can be obtained from skin prick testing and from serum IgE testing. The presence of a positive skin prick test or of elevated levels of specific IgE antibodies to codfish in the blood can indicate an allergy to Atlantic codfish. [6] by T Kalic · 2021 · Cited by 24 — Diagnosis of IgE-mediated fish allergy is usually done by assessing the clinical history, performing skin testing using commercially available fish extracts, and measuring serum IgE levels.

Treatment Options for Atlantic Cod Allergy

Atlantic cod allergy, like other fish allergies, can be managed through a combination of avoidance and medication. While there is no specific treatment to cure the allergy, certain medications can help alleviate symptoms.

• Antihistamines: Over-the-counter (OTC) antihistamines, such as diphenhydramine or loratadine, can provide relief for mild allergic reactions [6]. However, it's essential to consult with a healthcare provider before using these medications.
• Epinephrine auto-injectors: In severe cases of anaphylaxis, epinephrine auto-injectors like EpiPen or Auvi-Q are administered to help stabilize the patient until medical attention is received [2].
• Oral Immunotherapy (OIT): Research suggests that OIT could be a potential treatment option for fish allergies, including Atlantic cod allergy. However, this approach requires careful monitoring and should only be attempted under the guidance of a healthcare professional [8].

Important Considerations

When treating an Atlantic cod allergy, it's crucial to:

• Avoid exposure: The most effective way to manage the allergy is to avoid consuming Atlantic cod and other fish products altogether.
• Consult a healthcare provider: If symptoms persist or worsen, consult with a healthcare professional for personalized guidance and treatment.

References

[1] Dijkema, D. (2022). Fish Allergy Management and Treatment. [Source: Search Result 4]

[2] Nakonechna, A. (2024). Oral formula for decreasing food allergy risk and treatment for food allergy. [Source: Search Result 7]

[3] More, D. (2022). Fish Allergy Symptoms, Diagnosis, Treatment, and Coping. [Source: Search Result 14]

[4] Seafood allergy is the most common food allergy in adults and among the six most prevalent food allergies... [Source: Search Result 10]

[5] Crustacean was the predominant allergy-inducing food (3.8%), followed by fin fish (1.2%) and mollusk (1.0%) in a study population of more than 8600 participants. [Source: Search Result 11]

[6] Medication: Over-the-counter antihistamines can provide relief for mild allergic reactions, but always consult with a healthcare provider before using them. [Source: Search Result 6]

[7] Oct 15, 2020 — In codfish, the major allergen is the muscle protein parvalbumin, which is a calcium-binding protein. Parvalbumin is also found in other fish species, including Atlantic cod. [Source: Search Result 10]

[8] A study published in the Journal of Allergy and Clinical Immunology found that OIT with codfish was effective in desensitizing patients to the allergen. [Source: Search Result 15]

[9] Symptoms, including any that may seem unrelated to an allergy; Family history of allergies and asthma, including specific types of allergies if you know them; Medications, vitamins, herbs or other supplements you're taking, and the dosages; Questions to ask your health care provider; Questions related to shellfish allergy include: [Source: Search Result 12]

[10] Seafood allergy (SA), including allergy to shellfish (crustacean and mollusks) and fish, is one of the most common food allergies causing anaphylaxis in adults and children. [Source: Search Result 13]

[11] A fish allergy is not the same as a shellfish allergy. Learn how a fish allergy is diagnosed and how to best manage symptoms. [Source: Search Result 14]

[12] The diagnosis of seafood allergies is complicated by cross-reactivity among fish allergens and between shellfish allergens and other arthropods. Current clinical diagnosis of seafood allergy is a complex algorithm that includes clinical assessment, skin prick test, specific IgE measurement

The differential diagnosis of Atlantic cod allergy involves considering other conditions that may present similarly to an allergic reaction to codfish.

According to [1], the main differential diagnosis of fish allergy consists of scombroid poisoning, particularly if the fish species had been tolerated very recently. This is because scombroid poisoning can cause symptoms similar to those experienced in a fish allergy, such as hives, itching, and swelling.

Additionally, patients with an allergy to codfish are often allergic to other fish species as well [2]. This is due to the similarity of the allergen parvalbumin in all fish species. Therefore, if a patient has been diagnosed with an Atlantic cod allergy, it's essential to consider the possibility of allergies to other fish species.

Other conditions that may be considered in the differential diagnosis of Atlantic cod allergy include:

• Infestation by the helminth Anisakis simplex [5], which can cause severe allergic reactions in some individuals.
• Clinical monosensitivity to cod with specific IgE to enolase and aldolase [6].
• Scombroid poisoning, particularly if the fish species had been tolerated very recently [8].

Accurate diagnosis of an Atlantic cod allergy is crucial to prevent severe reactions and ensure proper treatment. Skin or blood tests alone may not be sufficient, and a comprehensive evaluation by a healthcare professional is necessary.

References:

[1] Dijkema et al. (2022) - The main differential diagnosis of fish allergy consists of scombroid poisoning, particularly if the fish species had been tolerated very recently...

[2] Patients with allergy to codfish are often allergic to the other fish species as well.

[5] Infestation by the helminth Anisakis simplex results in the contamination of fish flesh, which can cause severe allergic reactions in some individuals.

[6] Clinical monosensitivity to cod with specific IgE to enolase and aldolase.

[8] The main differential diagnosis of fish allergy consists of scombroid poisoning, particularly if the fish species had been tolerated very recently...