crustacean allergy

Crustacean Allergy: A Common Type of Shellfish Allergy

A crustacean allergy is an IgE antibody-mediated reaction to proteins found in crustaceans, such as crabs, lobsters, crayfish, shrimp, and prawns. This type of shellfish allergy is the most common among all types of shellfish allergies.

Symptoms of Crustacean Allergy

The symptoms of a crustacean allergy can range from mild to severe and include:

• Itchy rashes or hives [9]
• Dizziness, which may result in fainting [9]
• Swelling of the mouth, tongue, face, or other regions [9]

In some cases, an allergic reaction to crustaceans can be severe and life-threatening, known as anaphylaxis. Symptoms of anaphylaxis include:

• Vomiting
• Dizziness or fainting
• Trouble breathing due to constricted airways

Prevalence and Lifelong Nature

Crustacean allergy is more common in teenagers and adults than in children [6]. It is usually a lifelong condition, with about 1% of the population affected by seafood allergies, which includes crustaceans [6].

Cross-Reactivity and Diagnosis

Individuals may react to both crustaceans and mollusks or only one type. Cross-reactivity within each category is common, meaning that an individual allergic to one type of shellfish may also be allergic to others in the same category [11]. Diagnosing a shellfish allergy involves skin prick and blood tests [11].

Important Considerations

It's essential for individuals with crustacean allergies to avoid consuming these foods altogether. In rare cases, without immediate treatment with epinephrine, anaphylaxis can lead to death [13].

Crustacean Allergy Signs and Symptoms

A crustacean allergy, also known as shellfish allergy, can cause a range of symptoms, from mild to severe. Here are some common signs and symptoms:

• Skin reactions: Hives (urticaria), itchy skin, and skin redness are common symptoms of a crustacean allergy.
• Mouth and throat itching: Some people may experience itching in the mouth and throat after consuming shellfish.
• Lip swelling: Swelling of the lips is another possible symptom.
• Respiratory issues: Wheezing, trouble breathing, coughing, hoarseness, and throat tightness can occur due to a crustacean allergy.
• Gastrointestinal symptoms: Belly pain, vomiting, diarrhea, and nausea are also common signs of a shellfish allergy.

Severe reactions

In severe cases, a crustacean allergy can cause more serious symptoms, including:

• Anaphylaxis: A life-threatening allergic reaction that requires immediate medical attention.
• Flushing: Redness and warmth of the skin due to increased blood flow.
• Dizziness: Feeling lightheaded or dizzy after consuming shellfish.

References

• [1] Symptoms · Hives · Itchy, irritated skin · Nasal stuffiness (congestion) · Swelling of the lips, face, tongue and throat, or other parts of the ... (Search result 1)
• [2] If your mouth itches, or if you develop hives or a stomachache after eating crab, lobster or other shellfish, you may have a shellfish allergy, a condition that ... (Search result 2)
• [3] May 16, 2022 — The most common symptom is raised red bumps of skin (hives). Other symptoms include wheezing and trouble breathing, cramps, nausea or vomiting. (Search result 3)
• [4] Oct 6, 2022 — Patients with shellfish allergy can develop mouth and throat itching, lip swelling and skin reactions, such as hives, puffy eyes and skin ... (Search result 4)
• [5] Sep 20, 2024 — What are symptoms of shellfish allergy? · mouth and throat itching · lip swelling · skin reactions, such as hives, puffy eyes and skin redness. (Search result 6)

Standard Diagnostic Tests for Crustacean Allergy

Crustacean allergy, also known as shellfish allergy, can be diagnosed using several standard tests. These tests help identify the presence of allergens in the body and confirm a diagnosis.

• Skin Prick Test (SPT): This test involves placing a small amount of crustacean extract on the skin and pricking it with a tiny needle to introduce the allergen. If you're allergic, a raised red bump will appear within 15-20 minutes.
• Serum-Specific IgE Antibody Test: This blood test measures the levels of specific IgE antibodies in your bloodstream. Elevated levels indicate an allergy.
• Oral Food Challenge (OFC): In this test, you'll be asked to consume a small amount of crustacean-based food under medical supervision. If symptoms occur, it confirms an allergy.

Other Diagnostic Tests

Additional tests may be used to confirm a diagnosis or rule out other conditions:

• Immunoglobulin E (IgE) Antibody Test: This blood test measures the levels of IgE antibodies in your bloodstream.
• Seafood Allergy Panel: This panel measures IgE antibodies produced in response to certain seafood allergens.

Important Notes

• A negative test result doesn't necessarily rule out an allergy, as some people may still experience symptoms despite a negative test.
• The severity of an allergic reaction cannot be predicted by the size of the skin test wheal or the level of IgE antibodies.
• An allergist will use these tests and your medical history to make a diagnosis.

References

1. [2] - Routine workup would involve a thorough review of clinical history, a skin prick test, and a serum-specific IgE antibody test to whole shrimp and tropomyosin.
2. [3] - Current clinical diagnosis of seafood allergy is a complex algorithm that includes clinical assessment, skin prick test, specific IgE measurement, and oral food challenges.
3. [5] - Symptoms include itching, hives, worsening eczema, tingling or swelling of the lips, tongue, or throat, and chest tightness.
4. [6] - The Seafood Allergy Panel measures immunoglobulin E (IgE) antibodies produced in the blood in response to certain seafood allergens.
5. [11] - Approximately 60% of patients with clinical allergy to crustacean demonstrate specific IgE binding to tropomyosin.

These tests and references provide a comprehensive overview of diagnostic tests for crustacean allergy.

Treatment Options for Crustacean Allergy

Crustacean allergy, also known as shellfish allergy, can be treated with various medications to alleviate symptoms and prevent severe reactions.

• Antihistamines: Antihistamines such as loratadine (Claritin) or diphenhydramine (Benadryl) are commonly prescribed to treat mild symptoms of a crustacean allergy, including rash, itchiness, and hives [6][2].
• Corticosteroids: Corticosteroids may be prescribed to reduce inflammation and swelling in the body. They can be used alone or in combination with antihistamines to treat mild symptoms [3][4].
• Anti-inflammatory drugs: Anti-inflammatory drugs such as omalizumab (Xolair) are also used to treat crustacean allergy, especially for those who experience severe reactions [1][4].

Important Note

It's essential to note that the only definitive treatment for a shellfish allergy is strict avoidance and elimination of any foods containing shellfish from your diet [8]. If you have a crustacean allergy, it's crucial to inform your healthcare provider about your condition to receive proper guidance on medication use.

References:

[1] Oct 6, 2022 — Anti-inflammatory drugs (such as corticosteroids) and anti-IgE (like omalizumab) are mainstream nonspecific treatments that can be used alone or ... [2] Take a non-drowsy antihistamine, such as loratadine (Claritin), as your doctor recommends. Be safe with medicines. Read and follow all instructions on the label ... [3] Other medications, such as antihistamine and corticosteroids, may be prescribed to treat mild symptoms of a food allergy, but it is important to note that there ... [4] Oct 6, 2022 — Anti-inflammatory drugs (such as corticosteroids) and anti-IgE (like omalizumab) are mainstream nonspecific treatments that can be used alone or ... [5] If you have mild symptoms, your healthcare provider may recommend an antihistamine. However, only epinephrine can treat the severe symptoms of anaphylaxis. Does ... [6] Take a non-drowsy antihistamine, such as loratadine (Claritin), as your doctor recommends. Be safe with medicines. Read and follow all instructions on the label ... [7] Apr 26, 2022 — In most cases, your allergist will recommend antihistamines or corticosteroids to offer some relief from symptoms. [8] The best and only definitive treatment for shellfish allergies is strict avoidance and elimination of any foods containing shellfish from your diet.

Differential Diagnoses for Crustacean Allergy

Crustacean allergy, also known as shellfish allergy, can be challenging to diagnose due to its similarity with other conditions. Here are some differential diagnoses that should be considered:

• Bacterial gastroenteritis: This condition can present with symptoms similar to those of crustacean allergy, such as nausea, vomiting, and diarrhea [1].
• Celiac disease: Celiac disease is an autoimmune disorder that causes the immune system to react to gluten. Some people with celiac disease may also experience skin rashes or itching, which can be mistaken