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Alpha-gal anaphylaxis: the first case report in Italy
A M Calamari1, M Poppa2, D Villalta3
1Ospedale Castelli, Via Crocetta, 28921 Pallanza (VB), Italy.
European Annals of Allergy and Clinical Immunology
|September 11, 2015
Summary
A man experienced delayed anaphylaxis after eating meat, linked to prior tick bites. Testing confirmed alpha-gal syndrome, an allergy to a sugar molecule found in red meat.
Area of Science:
- Immunology
- Allergology
- Epidemiology
Background:
- Alpha-gal syndrome is an allergic reaction to galactose-alpha-1,3-galactose, a carbohydrate found in most mammals.
- This syndrome is typically associated with prior exposure to the alpha-gal molecule, often through tick bites.
Observation:
- A 55-year-old man presented with anaphylactic shock six hours post-meat consumption.
- The patient reported multiple tick bites in the preceding months.
- Delayed onset of symptoms (hours after ingestion) is a characteristic feature.
Findings:
- Serum specific IgE testing revealed strong positivity for alpha-gal antibodies.
- The clinical presentation and diagnostic results confirmed alpha-gal anaphylaxis.
- The findings establish a causal link between tick bites, alpha-gal sensitization, and delayed meat allergy.
Implications:
- This case highlights the importance of considering alpha-gal syndrome in patients with unexplained anaphylaxis, particularly after meat ingestion.
- Tick bite prevention is crucial for mitigating the risk of developing alpha-gal syndrome.
- Further research into the mechanisms and prevalence of delayed-onset food allergies is warranted.
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