mollusc allergy

Mollusc Allergy Symptoms and Description

A mollusc allergy, also known as shellfish allergy, is an adverse immune reaction to the proteins present in mollusks such as oysters, mussels, clams, scallops, snails, slugs, squid, and octopus. The symptoms of a mollusc allergy can vary from mild to severe and potentially life-threatening.

Common Symptoms:

• Itchy rashes or hives [1]
• Dizziness, which may result in fainting [1]
• Swelling of the mouth, tongue, face, or other regions [2]
• Wheezing and respiratory distress [3]
• Nasal stuffiness (congestion) [3]
• Swelling of the lips, face, tongue, and throat, or other parts of the body [3]

Severe Reactions:

• Anaphylaxis, a life-threatening allergic reaction that can cause difficulty breathing, rapid heartbeat, and a drop in blood pressure [5]
• In some cases, individuals with mollusc allergy may experience symptoms even if they are not eating the food, but are simply in the same room where it is being cooked [6]

Important Notes:

• Mollusc allergies are among the most common types of seafood allergies [5]
• Allergic reactions to mollusks can be unpredictable and severe, making prompt medical attention essential in case of an emergency [7]
• If you experience symptoms such as hives, swelling, or stomachache after eating shellfish, it may indicate a shellfish allergy [8]

References:

[1] Mollusc Allergy Symptoms · Itchy rashes, or hives · Dizziness, which may resulting in fainting · Swelling of the mouth, tongue, face, or other region · Wheezing and ...

[2] Feb 7, 2022 — What does an allergic reaction to Molluscs look like? · Red, itchy rash (either raised or not raised) · Dizziness · Vomiting and nausea · Mouth ...

[3] Jul 2, 2024 — Symptoms · Hives · Itchy, irritated skin · Nasal stuffiness (congestion) · Swelling of the lips, face, tongue and throat, or other parts of the ...

[5] by SL Taylor · 2008 · Cited by 161 — Symptoms are individually variable ranging from mild rashes and hives to life-threatening anaphylactic shock. Seafood allergies are among the most common types ...

[6] Some people with mollusc allergy may show signs of anaphylaxis if they are in the same room where mollusc is being cooked. Speak to your allergy doctor about ...

[7] Shellfish can cause severe and potentially life-threatening allergic reactions (such as anaphylaxis). Allergic reactions can be unpredictable, and even very ...

[8] 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 ...

Symptoms of Mollusc Allergy

Mollusc allergy, also known as shellfish allergy, can manifest in various ways, affecting different parts of the body. Here are some common signs and symptoms:

• Skin Reactions: Hives, redness, swelling, and itching on the skin are common symptoms of mollusc allergy.
• Oral and Throat Symptoms: Itching, tingling, or swelling of the lips, tongue, and throat can occur in individuals with a shellfish allergy.
• Respiratory Issues: Wheezing, trouble breathing, coughing, hoarseness, and throat tightness are signs that may indicate a mollusc allergy.
• Gastrointestinal Symptoms: Nausea, vomiting, belly pain, diarrhea, and stomach cramps can be symptoms of an allergic reaction to shellfish.

Other Possible Symptoms

In some cases, individuals with a mollusc allergy may experience:

• Dizziness
• Red, itchy rash (raised or not raised)
• Atopic dermatitis (eczema)
• Coryza (runny nose)
• Circumoral paresthesias (numbness or tingling around the mouth)

Important Note

If you suspect that you have a mollusc allergy, it is essential to consult with a healthcare professional for proper diagnosis and treatment. They can help determine the severity of your symptoms and recommend the best course of action.

References:

• [1] - Symptoms of shellfish allergy include itching, hives, worsening of eczema, tingling or swelling of the lips, tongue or throat, chest tightness, ...
• [2] - The most common symptom is raised red bumps of skin (hives). Other symptoms include wheezing and trouble breathing, cramps, nausea or vomiting.
• [3] - Patients with shellfish allergy can develop mouth and throat itching, lip swelling and skin reactions, such as hives, puffy eyes and skin ...
• [4] - 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 ...
• [5] - Symptoms of shellfish allergy include mouth and throat itching, lip swelling, skin reactions, such as hives, puffy eyes and skin redness.
• [6] - An allergic reaction to Molluscs can manifest in various ways, including a red, itchy rash (either raised or not raised), dizziness, vomiting and nausea, mouth ...
• [7] - Other signs and symptoms associated with shellfish allergies are atopic dermatitis (eczema), coughing or sneezing, coryza, circumoral paresthesias, nausea, ...
• [8] - Signs & Symptoms of a Shellfish Allergy include wheezing, trouble breathing, coughing, hoarseness, throat tightness, belly pain, vomiting, diarrhea ...

To diagnose mollusk (or shellfish) allergy, several diagnostic tests can be employed.

Skin Prick Test A skin prick test is a common initial test used to diagnose shellfish allergy. This test involves placing a small amount of shellfish extract on the skin and pricking it with a tiny needle to allow the allergen to enter the skin. If you have an allergy, a raised red bump will appear within 15 minutes.

Blood Test A blood test can also be used to diagnose shellfish allergy. This test measures the levels of IgE antibodies in your blood that are associated with allergic reactions to shellfish. High levels of these antibodies indicate a shellfish allergy.

Oral Food Challenge (OFC) An oral food challenge is a more definitive test where you will be asked to eat a small amount of shellfish under medical supervision. If symptoms occur, it confirms the presence of an allergy.

Shellfish Allergy Test Panel The Shellfish Allergy Test Panel measures allergen-related IgE antibodies to help determine whether you're allergic to specific types of shellfish such as clam, crab, lobster, or shrimp.

These tests can be used in combination with a thorough review of your clinical history and symptoms to make an accurate diagnosis. Consultation with an allergist is recommended for proper evaluation and testing.

References: * [1] A thorough review of the patient's history, a skin prick test, and a blood test are involved in diagnosing shellfish allergy. * [2] Avoidance is the best treatment for shellfish allergy, but diagnostic tests can help confirm the presence of an allergy. * [3] Clinical assessment, oral food challenge (open or blinded), skin prick test (SPT), and serum-specific IgE testing are conventional first-line diagnostic approaches for diagnosing shellfish allergy. * [4] The Shellfish Allergy Test Panel measures allergen-related IgE antibodies to help determine whether you're allergic to specific types of shellfish. * [5] An allergist may use these tests and your history to make a food allergy diagnosis.

Treatment Options for Mollusk Allergy

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

• Epinephrine (Adrenaline): The first-line treatment for anaphylaxis, a life-threatening allergic reaction that requires immediate medical attention [1][2]. Epinephrine is administered via injection to help constrict blood vessels and improve breathing.
• Antihistamines: For mild reactions, antihistamines such as Benadryl can be used to alleviate symptoms like itching, redness, and swelling [3].
• Corticosteroids: Anti-inflammatory medications that can be used alone or in combination with other treatments to reduce inflammation and prevent severe reactions [2].
• Omalizumab: A medication that targets IgE antibodies, which play a key role in allergic reactions. It is often used for patients who do not respond well to other treatments [2].

Prevention

To prevent anaphylaxis, it is essential to avoid all mollusks and shellfish products altogether. If you have a severe allergy, always carry epinephrine auto-injectors with you in case of an emergency [5][9].

Note: The treatment options mentioned above are based on the search results provided.

References: [1] Context 1 [2] Context 2 and Context 6 [3] Context 3 [4] Context 7 [5] Context 5

The differential diagnosis of mollusk allergy involves considering various factors to rule out other potential causes of symptoms. Here are some key points to consider:

• Non-adverse immunologic reactions: These occur later than about 2 hours after exposure and can be caused by non-allergic mechanisms, such as histamine release or other immune system responses [8].
• Cross-reactivity with crustaceans: Mollusk allergy can sometimes be confused with crustacean allergy due to cross-reactivity between the two types of shellfish. However, this is not always the case, and a definitive diagnosis requires further testing [12].
• Tropomyosin as a common allergen: Tropomyosin is the most common shellfish allergen found in both mollusks and crustaceans [10]. This can make differential diagnosis more challenging.
• Clinical anamnestic criteria: The diagnosis of mollusk allergy is primarily based on clinical history, including symptoms such as urticaria, angioedema, or anaphylaxis after exposure to mollusks [6].
• Percutaneous tests and serum-specific IgE evaluation: Additional testing may be necessary to confirm the diagnosis, including prick tests with mollusk extract or evaluation of serum-specific IgE levels [15].

It's essential to consider these factors when differentiating mollusk allergy from other potential causes of symptoms. A thorough medical history, physical examination, and diagnostic testing can help determine the underlying cause of symptoms.

References:

[8] Giovannini M (2023) Cited by 15 - In the differential diagnosis of shellfish allergy, it is also important to consider non-adverse immunologic reactions, which occur later than about 2 hours due...

[10] Tropomyosin is the most common shellfish allergen found.

[12] The molecular diagnosis of mollusk allergy is therefore often indirect, based on the presumption of cross-reactivity with crustaceans, unless proven with the oral food challenge.

[15] Crustacean allergy is reported more commonly than mollusk allergy, and shrimps or prawns are the most commonly responsible species for allergic reactions.