title: High prevalence of seropositivity to a major allergen of Anisakis simplex, Ani s 1, in dyspeptic patients.
abstract: Finding evidence of anisakidosis requires invasive methods. We have developed a serological assay based on the detection of an immunoglobulin E (IgE) specifically directed against Ani s 1 protein, a major parasite allergen of Anisakis simplex, which has shown a high level of accuracy in the diagnosis of anisakidosis. We used this tool to determine the prevalence of anti-Ani s 1 IgE in dyspeptic patients and to investigate if its seropositivity could be related to epidemiological factors other than raw fish consumption. A total of 174 dyspeptic patients who submitted to upper digestive tract endoscopy were studied. Specific IgE against Ani s 1 was determined by immunoblotting. Quantitative information on smoking, alcohol consumption, and fish consumption as well as a history of gastric surgery was recorded. Twenty-four (13.8%) patients were seropositive for Ani s 1 protein. The seroprevalence of anti-Ani s 1 IgE increased with age in patients who were less than 62 years old (P = 0.047). Seropositivity to Ani s 1 was associated with the consumption of fish in vinegar (P < 0.001), raw fish (P = 0.001), and smoked fish (P = 0.007). There was no relationship between anti-Ani s 1 IgE seropositivity and the number of cigarettes smoked (P = 0.098) or alcohol intake (P = 0.179). Five patients had undergone previous gastric surgery, and three of those patients were seropositive for Ani s 1 (P = 0.019). In multivariate analysis, the consumption of fish in vinegar (P = 0.006), raw fish (P = 0.017), and smoked fish (P = 0.002) and a history of gastric surgery (P = 0.005) were independent factors associated with anti-Ani s 1 IgE detection. In conclusion, at present, anisakidosis might frequently be underdiagnosed, and it might have a clinical role in patients with upper dyspeptic symptoms. Uncooked-fish ingestion and previous gastric surgery were associated with seropositivity for Ani s 1 protein.
authors.affiliation: Services of Infectious Diseases, Hospital Carlos III and Department of Medicine, European University of Madrid, Madrid, Spain. carlostororueda@hotmail.com
authors.forename: Carlos
authors.initials: C
authors.lastname: Toro
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Caballero
authors.forename: Margarita
authors.initials: M
authors.lastname: Baquero
authors.forename: Javier
authors.initials: J
authors.lastname: García-Samaniego
authors.forename: Isabel
authors.initials: I
authors.lastname: Casado
authors.forename: Margarita
authors.initials: M
authors.lastname: Rubio
authors.forename: Ignacio
authors.initials: I
authors.lastname: Moneo
mesh_terms: D000485:Allergens / Q000276:immunology*; D000818:Animals; D017129:Anisakiasis / Q000175:diagnosis* / Q000276:immunology*; D017163:Anisakis / Q000276:immunology*; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth; D002135:Calcium-Binding Proteins / Q000276:immunology*; D004415:Dyspepsia / Q000276:immunology* / Q000469:parasitology*; D005399:Fishes / Q000469:parasitology; D016266:Food Parasitology; D015801:Helminth Proteins / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood
chemical_list: D000485:Allergens; D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D002135:Calcium-Binding Proteins; D015801:Helminth Proteins; C412511:troponin-like protein, Anisakis simplex; D007073:Immunoglobulin E