Summary about Disease
Quince allergy is an adverse immune reaction to proteins found in the quince fruit ( Cydonia oblonga). It is less common than allergies to other fruits like apples or peaches, but individuals with allergies to related fruits (like those in the Rosaceae family) may be more susceptible due to cross-reactivity. Reactions can range from mild oral allergy syndrome to more severe systemic reactions.
Symptoms
Symptoms of quince allergy can vary in severity and may include:
Oral Allergy Syndrome (OAS): Itching, tingling, or swelling of the lips, tongue, mouth, or throat shortly after eating quince.
Skin Reactions: Hives, eczema, itching, or rash.
Gastrointestinal Issues: Nausea, vomiting, abdominal pain, or diarrhea.
Respiratory Problems: Runny nose, sneezing, coughing, wheezing, or difficulty breathing.
Anaphylaxis (Severe allergic reaction): Difficulty breathing, throat swelling, dizziness, loss of consciousness, and a sudden drop in blood pressure. This is a medical emergency.
Causes
Quince allergy is caused by the immune system mistakenly identifying certain proteins in quince as harmful. When an allergic individual consumes or comes into contact with quince, their immune system releases histamine and other chemicals, leading to allergic symptoms. Cross-reactivity with other fruits in the Rosaceae family (apples, pears, peaches, apricots, plums, cherries, almonds) is a common cause; pollen allergies (birch pollen) may also play a role.
Medicine Used
Antihistamines: For mild to moderate symptoms like itching, hives, or runny nose.
Corticosteroid creams: To reduce inflammation and itching associated with skin rashes.
Epinephrine (EpiPen): For severe allergic reactions (anaphylaxis). This is an emergency medication that needs to be administered immediately, followed by seeking medical attention.
Bronchodilators (inhalers): For respiratory symptoms like wheezing or difficulty breathing.
Is Communicable
No, quince allergy is not communicable. It is an immune response to a specific substance (quince proteins) and cannot be spread from person to person.
Precautions
Avoid Quince: The most important precaution is strict avoidance of quince in all forms (raw, cooked, processed).
Read Labels Carefully: Check ingredient lists of processed foods, beverages, and cosmetics for quince or related fruits.
Inform Restaurants and Food Handlers: When eating out, inform staff about the allergy to prevent cross-contamination.
Carry Emergency Medication: If at risk for anaphylaxis, carry an epinephrine auto-injector (EpiPen) at all times and know how to use it.
Wear a Medical Alert Bracelet: This can inform others about the allergy in case of an emergency.
Allergy Testing: Undergo allergy testing to confirm the allergy and identify potential cross-reactive allergens.
How long does an outbreak last?
The duration of symptoms depends on the severity of the reaction and the amount of quince consumed. Mild symptoms from oral allergy syndrome might resolve within minutes to a few hours after the quince is removed. More severe reactions, especially if untreated, can last for several hours or even days. Anaphylaxis requires immediate treatment to prevent life-threatening complications.
How is it diagnosed?
Medical History: A detailed discussion of symptoms, food history, and family history of allergies.
Skin Prick Test: A small amount of quince extract is applied to the skin, and the skin is pricked to see if a reaction occurs.
Specific IgE Blood Test (RAST or ImmunoCAP): Measures the amount of IgE antibodies specific to quince in the blood.
Oral Food Challenge: Under medical supervision, small amounts of quince are ingested to observe for any allergic reactions. This should only be performed in a clinical setting with emergency medical equipment available.
Timeline of Symptoms
The timeline of symptoms varies, but it usually follows this pattern:
Immediate Reaction (within minutes): Oral allergy syndrome (itching, tingling), hives, or respiratory symptoms may begin almost immediately after contact or ingestion.
Within 30 minutes to 2 hours: Gastrointestinal symptoms, skin rashes, or worsening of respiratory problems may develop.
Anaphylaxis (within minutes to hours): This is a rapid and severe reaction that requires immediate medical attention.
Delayed Reactions (hours to days): In some cases, skin reactions like eczema may appear days after exposure.
Important Considerations
Cross-Reactivity: Be aware of potential cross-reactivity with other fruits in the Rosaceae family and birch pollen.
Anaphylaxis Risk: If you have experienced anaphylaxis to quince, always carry an epinephrine auto-injector and know how to use it.
Hidden Sources: Be cautious of hidden sources of quince in processed foods, jams, jellies, or certain liqueurs.
Professional Guidance: Work closely with an allergist for diagnosis, management, and personalized recommendations.
Cooking May Not Eliminate Allergenicity: Cooking quince may reduce the allergenic potential for some individuals, but it is not reliable for preventing reactions in all cases. Avoidance remains the safest approach.