Vundamati VS, Patel SR, Patel R, Eriskin N, Tila-Cohen B, et al.
Cureus •
Alpha-gal syndrome (AGS) is characterized by an IgE-mediated immune response against galactose-α-1,3-galactose (α-gal). In the United States, the principal vector is the lone star tick, whose range has expanded nationwide. A lone star tick bite delivers α-gal into human skin via its saliva, triggering an IgE response in susceptible individuals. Vomiting, urticaria, and anaphylaxis may occur immediately or hours after exposure. However, perioperative ingredients, such as gelatin, monoclonal antibodies, stearic acid, and other mammalian-derived products, have triggered anaphylactic shock in patients with AGS. These nuances complicate AGS management as many cases go unrecognized. This review aims to look beyond traditional food-related reactions, characterize the range of presentations, and improve management of this increasingly recognized condition. The inclusion criteria required original research in English peer-reviewed journals between January 1, 2000, and March 22, 2026. Eligible studies included quantitative, qualitative, and mixed-method designs examining AGS acquisition. Relevant tick studies were included. Systematic reviews, scoping reviews, meta-analyses, case reports, series, and studies involving pregnant individuals or children, lacking full-text, duplicate publications, or overlapping datasets were excluded. Authors screened publications using Rayyan (Rayyan Systems Inc., Cambridge, USA). Discrepancies were resolved through discussion. Of the 729 records identified, 14 studies met the inclusion criteria. Understanding the diverse spectrum of allergic manifestations of this condition is vital. This review consolidates findings on AGS-related complications, including immediate and delayed anaphylaxis, hypersensitivity reactions to mammalian-derived medical products, and blood transfusions. However, the available evidence is primarily derived from observational studies conducted in the United States, which may limit the generalizability of current findings. By highlighting the broader implications of AGS, this review underscores awareness in acute and perioperative settings.
Rao S, Rathore SS, Goyal RM, Narakornpichit A, Karkra R, et al.
Neurogastroenterology and motility •
Alpha-gal syndrome (AGS) is an IgE-mediated hypersensitivity to galactose-α-1,3-galactose, triggered by tick bites. It typically presents with delayed onset allergic or gastrointestinal symptoms after red meat consumption. This study aims to evaluate the prevalence of clinical symptoms and outcomes in AGS patients. A systematic search of PubMed, Embase, and Cochrane Central was conducted to identify studies with at least five AGS patients that utilized alpha-gal IgE for diagnosis and reported symptomatology. A random-effects model calculated pooled prevalence and 95% confidence intervals (CIs) for clinical characteristics of AGS. Of the 739 studies screened, 15 met the inclusion criteria, comprising 1162 AGS patients (57% female). Urticaria was identified as the most prevalent symptom (63.8%, CI: 34.5-88.3, I = 98.8%). At least one gastrointestinal symptom was reported in 69.2% of patients (CI: 49.3-85.9, I = 97.5%), including abdominal pain (58.3%, CI: 36.0-78.9, I = 96.0%), diarrhea (41.7%, CI: 22.3-62.5, I = 93.4%), nausea (39.1%, CI: 29.2-49.6, I = 79.1%), and vomiting (31.1%, CI: 21.9-41.2, I = 70.4%). Tick bite history was recalled by 78.7% (CI: 46.4-98.1; I = 99.1%), and 91.8% (CI: 84.6-96.8; I = 70.3%) had symptom onset ≥ 1 h post red meat intake. Symptomatic improvement was observed in 86.5% (CI: 73.9-95.4, I = 80.9%) of patients, with complete resolution in 42.7% (CI: 26.4-59.8, I = 73.8%). AGS typically presents with delayed onset allergic and GI symptoms after red meat intake, often with tick bite history. Majority of patients report symptomatic improvement on follow-up.
Patel R, Patel A, Biswas R, Hsieh B, Ramasamy D, et al.
Case reports in immunology •
Alpha-gal syndrome (AGS) is an uncommon IgE-mediated allergy to mammalian-derived products, caused by sensitization to the oligosaccharide galactose-α-1,3-galactose (alpha-gal) after tick exposure. Although AGS is best recognized for delayed anaphylaxis following ingestion of red meat, its implications for exposure to mammalian-derived biomaterials remain poorly characterized. We present an elderly woman with AGS who required transcatheter aortic valve replacement (TAVR) using a bovine bioprosthesis. An 84-year-old woman with serologically confirmed AGS following a Lone Star tick bite in 2012 presented with symptomatic severe aortic stenosis. Her clinical history included multiple allergic reactions to beef, persistently elevated IgE to beef, pork, and lamb, and a specific alpha-gal IgE >100 kU/L. Following a multidisciplinary evaluation, she was not considered a candidate for a mechanical valve. A prophylactic regimen was implemented, including cetirizine, omalizumab, and 60 mg prednisone 6 h prior to TAVR. The procedure was successfully performed with a bovine-derived bioprosthetic valve. Perioperative tryptase levels remained within normal range (5.2 µg/L), and no hypersensitivity reactions occurred. Postoperatively, prednisone was tapered, while fexofenadine and omalizumab were continued for 6 months. This case highlights that bioprosthetic valve replacement can be safely performed in AGS patients through multidisciplinary planning and individualized prophylaxis strategies. Further data are needed to develop standardized perioperative management protocols for this rare but clinically significant condition.
Food allergies are relatively prevalent, but mammalian meat allergy remains uncommon and represents an important, potentially acute healthcare risk. This risk is partly because both clinicians and the public lack awareness of this serious allergy, which is unique in three important ways: it incurs a delayed reaction, it is induced by a carbohydrate rather than a protein, and it is linked to tick bites. Although various symptoms are possible, its unique presentation means that mammalian meat allergy is often presented to the dermatologist. We review this challenging subject, which is particularly salient considering the unique connection between ticks and mammalian meat allergy, the expanding tick territory, and the dependency by so many on meat products, not only in the diet but also in medications and medical devices.
Ethyl acetate extracts of Sephadex LH20-purified proanthocyanidins of American cranberry (Vaccinium macrocarpon Ait.) exhibited potent biological activity by inhibiting adherence of uropathogenic isolates of P-fimbriated Escherichia coli bacteria to cellular surfaces containing alpha-Gal(1-->4)beta-Gal receptor sequences similar to those on epithelial cells in the urinary tract. The chemical structures of the proanthocyanidins were determined by 13C NMR, electrospray mass spectrometry, matrix-assisted laser absorption time-of-flight mass spectrometry and by acid catalyzed degradation with phloroglucinol. The proanthocyanidin molecules consisted predominantly of epicatechin units with mainly DP of 4 and 5 containing at least one A-type linkage. The procyanidin A2 was the most common terminating unit occurring about four times as frequently as the epicatechin monomer.
