Gastrointestinal motility and disorders (152)Diet and metabolism studies (40)Gut microbiota and health (32)Helicobacter pylori-related gastroenterology studies (24)Gastroesophageal reflux and treatments (24)
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.
Lesmana E, Rao S, Keehn A, Edwinson AL, Makol A, et al.
Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association •
Alpha-gal syndrome (AGS) is an IgE-mediated allergic reaction to galactose-α-1,3-galactose, primarily linked with Lone Star tick bites in the United States. It presents with symptoms ranging from urticaria and gastrointestinal (GI) manifestations to delayed anaphylaxis following red meat consumption. We aimed to study AGS patients' clinical manifestations, diagnosis, and outcomes. A retrospective chart review of patients who underwent serological testing for suspected AGS between 2014 and 2023 at Mayo Clinic was performed. Patients with positive serology were age and sex matched with those who tested negative. Clinical characteristics of seropositive cohort with and without GI symptoms were compared, and outcomes assessed. Of 1260 patients who underwent testing, 124 tested positive for AGS. They were matched with 380 seronegative control subjects. AGS patients reported a higher frequency of tick bites (odds ratio [OR], 26.0; 95% confidence interval [CI], 9.8-68.3), reported a higher prevalence of urticaria (56% vs 37%; P = .0008), and were less likely to have asthma (OR, 0.4; 95% CI, 0.3-0.7). They had a lower prevalence of heartburn (6% vs 12%; P = .03) and bloating (6% vs 13%; P = .03). A total of 47% had GI symptoms, and a higher proportion were female than those without GI symptoms (69% vs 35%; P = .002). During a mean follow-up of 27 months, 22 of 40 patients reported symptom resolution after avoiding red meat, and 7 were able to transition to regular diet. A diagnosis of AGS should be strongly considered in patients with a history of tick bites and clinical presentation of allergic or GI manifestations. Dietary intervention is effective in most but not all patients.