Alpha-gal syndrome

Editor-In-Chief: Prab R Tumpati, MD
Obesity, Sleep & Internal medicine
Founder, WikiMD Wellnesspedia &
W8MD medical weight loss NYC and sleep center NYC

Alpha-gal syndrome
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms	Urticaria, angioedema, anaphylaxis, gastrointestinal symptoms
Complications	N/A
Onset	3-6 hours after consumption of red meat or exposure to alpha-gal
Duration	Varies, can be chronic
Types	N/A
Causes	IgE antibody response to galactose-alpha-1,3-galactose
Risks	Tick bites, particularly from the Lone Star tick
Diagnosis	Blood test for specific IgE antibodies
Differential diagnosis	Food allergy, mast cell activation syndrome, idiopathic anaphylaxis
Prevention	Avoidance of red meat and products containing alpha-gal
Treatment	Antihistamines, epinephrine for severe reactions
Medication	N/A
Prognosis	N/A
Frequency	Increasing, particularly in the United States
Deaths	N/A

Alpha-gal_syndrome

Amblyomma americanum tick

Alpha-gal syndrome

Alpha-gal Syndrome

Alpha-gal syndrome is a type of allergy to red meat and other products made from mammals. It is caused by a reaction to a carbohydrate called galactose-alpha-1,3-galactose (alpha-gal), which is found in most mammals but not in humans, apes, or Old World monkeys.

Causes

Alpha-gal syndrome is primarily triggered by the bite of the Lone Star tick (Amblyomma americanum). The tick introduces alpha-gal into the body, which can lead to the development of an immune response. This immune response can cause allergic reactions when the affected individual consumes red meat or other products containing alpha-gal.

Symptoms

Symptoms of alpha-gal syndrome can vary but often include:

• Urticaria (hives)
• Angioedema (swelling)
• Gastrointestinal distress, such as diarrhea or abdominal pain
• Anaphylaxis, a severe, potentially life-threatening allergic reaction

Symptoms typically occur 3-6 hours after consuming red meat, which is longer than the immediate reaction seen in most food allergies.

Diagnosis

Diagnosis of alpha-gal syndrome involves a combination of clinical history, symptom assessment, and specific IgE blood tests that detect antibodies to alpha-gal. A positive test, along with a history of delayed allergic reactions to red meat, supports the diagnosis.

Management

Management of alpha-gal syndrome primarily involves avoiding red meat and other products that contain alpha-gal. This includes beef, pork, lamb, and venison. Patients are also advised to avoid gelatin and dairy products, which may contain alpha-gal. In cases of accidental exposure, treatment may involve the use of antihistamines or epinephrine for severe reactions. Patients are often advised to carry an epinephrine autoinjector in case of anaphylaxis.

Prevention

Preventing tick bites is crucial in reducing the risk of developing alpha-gal syndrome. This includes using insect repellent, wearing long sleeves and pants, and performing thorough tick checks after spending time outdoors.

See Also

• Allergy
• Anaphylaxis
• Tick
• Lone Star tick