Search Results (11)

Background/Objectives: Allergic features of anisakiasis, caused by ingestion of third-stage larvae of Anisakis simplex via raw or undercooked fish, manifest clinically as acute gastroallergic anisakiasis (GAA) or chronic urticaria with Anisakis sensitization (CU+). Differentiating these clinical phenotypes remains challenging. This study aimed to evaluate the maturation and avidity of specific antibodies (IgE, IgG4, IgG, and IgA) as biomarkers for discriminating between acute and chronic forms of anisakiasis. Methods: A prospective cohort of 65 patients from Madrid, Spain, was classified into three groups: GAA (n = 22), CU+ (n = 22), and chronic urticaria without sensitization (CU−, n = 21). Serum samples were analyzed for antigen-specific immunoglobulins using ELISA and Western blot. Avidity indices (AIs) were quantified through urea dissociation assays. Statistical comparisons and correlation analyses were performed to associate antibody avidity with clinical phenotype and demographic variables. Results: GAA patients exhibited significantly lower IgE avidity indices compared to CU+ individuals (mean AI: 79.9% vs. 88.5%), indicating a less mature IgE response during acute infection. Conversely, IgG4 and IgG avidity were elevated in GAA relative to CU+, reflecting an active but transient immune response. IgA antibodies were detected in both groups, although avidity differences lacked discriminatory capacity. No sex- or age-related differences in antibody avidity were observed. Longitudinal follow-up of GAA patients demonstrated an increase in IgE avidity over time. Conclusions: Quantitative assessment of antibody avidity, particularly for IgE and IgG4, enhances understanding of A. simplex immunopathogenesis and serves as a valuable biomarker for distinguishing acute from chronic clinical presentations. These findings support the use of avidity indices in the diagnosis, staging, and clinical management of anisakiasis. Full article

Background/Objectives: This study investigates the potential of Anisakis sp. as a novel source of α-Gal (Galα1-3Galβ1-4GlcNAc-R) epitopes capable of inducing allergic sensitization in humans. While α-Gal is classically associated with delayed IgE-mediated hypersensitivity following tick bites, emerging evidence suggests that parasitic helminths such as Anisakis sp. may also express α-Gal-containing glycoconjugates, offering an alternative sensitization pathway. Methods: Protein extracts from Anisakis sp. third-stage larvae and mammalian tissues (beef, pork) were analyzed by SDS-PAGE and Western blot using a monoclonal anti-α-Gal antibody (clone M86), and α-Gal epitopes were detected by ELISA. Sera from urticaria patients, stratified by Anisakis sp. sensitization status, were evaluated for anti-α-Gal IgG, IgE, and IgG4 antibodies. Inhibition assays assessed cross-reactivity. Results: Results confirmed the presence of α-Gal epitopes on Anisakis sp. proteins, with prominent bands at ~250 kDa and 65 kDa. Urticaria patients sensitized to Anisakis sp. exhibited significantly elevated anti-α-Gal antibody levels compared to controls. Inhibition ELISA demonstrated substantial reduction in antibody binding with Anisakis sp. extracts, indicating shared antigenic determinants with mammalian α-Gal. Conclusions: These findings establish Anisakis sp. as a source of α-Gal-containing glycoproteins capable of eliciting specific antibody responses in humans, highlighting a potential parasitic route for α-Gal sensitization. Full article

This study assessed the seroprevalence of anti-Anisakis simplex antibodies in Norwegian patients with inflammatory bowel disease (IBD), specifically ulcerative colitis (UC) and Crohn’s disease (CD), compared with healthy controls. Associations between anti-A. simplex antibody positivity and clinical or laboratory parameters in IBD were also explored. A total of 86 UC patients, 68 CD patients, and 41 healthy controls were prospectively enrolled from four Norwegian hospitals (2013–2022). Diagnosis and disease activity were established using standard clinical, endoscopic, and biomarker criteria. Serum samples were analyzed for total Ig, IgG, IgM, IgA, and IgE antibodies against A. simplex and Pseudoterranova decipiens using ELISA. Anti-A. simplex IgG seroprevalence was 4.9% in controls and 3.2% in IBD (3.5% UC, 2.9% CD). IgM seroprevalence was 0% in all groups. IgA seroprevalence was higher in IBD (16.2%) than controls (4.9%), with 14.0% in UC and 19.1% in CD. IgE seroprevalence was low across all groups. Smoking correlated with lower antibody levels and higher surgery rates. In UC, higher anti-A. simplex IgG and IgE levels were associated with milder disease and better prognosis. Anti-TNFα and azathioprine treatments were linked to higher anti-A. simplex IgA. Norwegian UC and CD patients had significantly higher anti-A. simplex total Ig and IgA seroprevalence than healthy controls, indicating increased exposure or immune response. Anti-A. simplex IgG and IgE may serve as markers of clinical activity in UC. Further research is warranted to clarify the clinical significance of these findings. Full article

Food-borne zoonoses, particularly anisakiosis caused by Anisakis spp., are an increasing public health concern due to the rising consumption of raw fish. Anisakiosis results from the ingestion of third-stage larvae of Anisakidae nematodes, with the genus Anisakis re-sponsible for approximately 97% of human cases. While regulatory protocols exist to minimize infection risk in commercial settings, domestic food preparation often lacks such safeguards, creating a gap in public health protection. In the Canary Islands, a major Spanish aquaculture region, farmed fish exhibit a low Anisakis prevalence, suggesting minimal risk from aquaculture products. In contrast, wild-caught fish demonstrate varia-ble parasitism, with recent studies reporting a 25% prevalence among commercial species. Methods: This study assessed Anisakis exposure in the Canary Islands by measuring specific IgG and IgE antibodies in 1043 serum samples collected from all seven islands between March 2014 and October 2015. ELISA assays detected anti-Anisakis antibodies, and the results were analyzed by age, sex, island, and isoclimatic zone. Results: Overall, 16.9% of samples were IgG-positive and 6.8% were IgE-positive. Seroprevalence was significantly higher in indi-viduals aged 60 years and above. Geographic heterogeneity was notable: La Palma had the highest IgG seroprevalence (35.3%), while El Hierro showed the highest IgE prevalence (16.3%). Temperate isoclimatic zones exhibited higher antibody prevalence than dry zones. These findings indicate variable Anisakis exposure across the Canary Islands, likely influenced by environmental and behavioral factors. Conclusions: The results highlight the need for targeted public health interventions to reduce the anisakiosis risk, particularly in regions and populations with elevated exposure. Full article

The diagnosis of allergic reactions to Anisakis remains challenging due to the lack of specific allergens available for routine clinical use. However, the latest version of the multiplex macroarray ALEX-2 now allows the detection of specific IgE against Ani s 1, the major species-specific allergen, as well as Ani s 3 (tropomyosin), a highly cross-reactive molecule with homologs in other allergenic sources. This study aimed to evaluate the potential role of ALEX-2 in diagnosing Anisakis sensitization by comparing it with a previously validated diagnostic algorithm. Serum samples from patients with suspected Anisakis sensitization were consecutively collected at an Italian allergy centre. Diagnosis was based on a history of allergic reactions following seafood consumption, along with negative test results for fish allergy. All patients underwent skin prick testing and specific IgE measurement for Anisakis (p4), Ascaris (p1), shrimp (f24), and Dermatophagoides pteronyssinus (d1), as well as tropomyosins from house dust mites (d205) and shrimp (f351). Additionally, the basophil activation test (BAT) using crude Anisakis extract was performed. Patients were also tested using the ALEX-2 allergy macroarray. Correlation analyses and multiple logistic regression models were applied to assess associations between conventional singleplex tests and the severity of clinical manifestations. A total of 33 eligible subjects were recruited, including 20 females (60.6%). Seven (21.2%) were aged 0–29 years, eleven (33.3%) were 30–60 years old, and fifteen (45.5%) were over 60 years old. ALEX-2 showed positivity for Ani s 1 or Ani s 3 in 39.39% (95% CI: 22.90–57.86%) of subjects with confirmed Anisakis sensitization. A significant correlation was observed between Ani s 3 (r = 0.31 [95% CI: 0.04–0.56], p = 0.01) and Ascaris (r = 0.35 [95% CI: 0.129–0.55], p = 0.004) levels and the severity of clinical reactions. Despite the limitations of this cross-sectional study, including a small sample size, our preliminary findings suggest that the ALEX-2 macroarray may not be sufficiently sensitive for the first-line diagnosis of Anisakis allergy. However, it could provide valuable additional information, as Ani s 1 positivity indicates primary sensitization to the nematode, while Ani s 3 positivity appears to correlate with clinical severity. Larger prospective longitudinal studies are needed to confirm these findings and further assess the predictive value of ALEX-2 in diagnosing Anisakis allergy. Full article

Background: Anisakis allergy has been increasing, and the diagnosis of it is based on specific serum IgE detection. Recently, the IgE-crosslinking-induced luciferase expression (EXiLE) test has been proposed as convenient tool for detecting functionally specific IgE antibodies. Here, we investigated if the EXiLE test is a useful tool in the diagnosis of Anisakis allergy. Methods: HuRa-40 cells were sensitized using six serum types from three patients with Anisakis allergy at the time of the initial test and after 6–12 months. Thereafter, various concentrations of Anisakis worm protein (AWP) were reacted to measure the degree of EXiLE. The degree of EXiLE was compared with Anisakis-specific IgE antibody levels measured by the CAP-FEIA method, and the IgE-antibody-binding protein profile was examined using IgE immunoblotting. Results: The results showed a good correlation between the CAP-FEIA values and EXiLE obtained with 5 μg/mL of AWP (R = 0.91, p < 0.01), a strong response on IgE immunoblotting in the region containing proteins weighing ≥40,000 Da. In addition, after the onset of Anisakis allergy, the degree of serum EXiLE decreased in two patients whose Anisakis-specific IgE antibody levels decreased over time but increased in one patient whose specific IgE antibodies increased after repeated antigen sensitization. Conclusions: Based on these data, the AWP-induced EXiLE test seemed to be useful and convenient for the diagnosis of Anisakis allergy, supplementing specific IgE determinants. After allergy onset, the use of this method to observe changes in specific IgE levels over time may be important for predicting the risk of recurrence. Full article

Background/Objectives: In a previous study, we described elevated anti-Anisakis IgG levels in septic patients in relation to disease severity. In this study, our objective was to analyze the evolution of anti-Anisakis immunoglobulins in septic patients during hospital admission and their association with αβ and γδ T cell subsets. Methods: We recruited 80 subjects: 40 patients with sepsis and 40 controls. αβ and γδ T cells were analyzed using flow cytometry. Apoptosis was also assessed, and anti-Anisakis antibodies were measured by ELISA in the sera of patients with sepsis and controls. Results: In the second analysis (7–10 after sepsis evolution), an increase in all specific antibody isotypes was identified in individuals with septic shock, except IgE. The levels of anti-Anisakis IgG and IgA were higher in the subjects with sepsis in the first analysis and continued to increase in the second analysis compared with the healthy control subjects. There was an increase in anti-Anisakis IgG and IgA levels in surviving patients and an increase in IgA levels in non-surviving patients. A rise in specific IgG and IgE levels was noted in the second analysis of patients with sepsis with αβ CD3+ T cell deficiency. Patients without γδ T cell deficiency had increased anti-Anisakis IgA levels 7–10 days after admission. Conclusions: Our results suggest a previous infection by Anisakis that could be involved in the subsequent septic process and be related to patients who have negative cultures in which the pathogen causing sepsis has not been identified. Full article

Dietary changes expose consumers to risks from Anisakis larvae in seafood, leading to parasitic diseases and allergies. Anisakis is recognized by EFSA as a significant hazard, with potential oncogenic implications. Diagnostic advancements, like the Basophil Activation Test (BAT), enhance sensitivity and accuracy in identifying Anisakis sensitization, complementing traditional IgE tests. We conducted a cross-sectional study on patients with allergic symptoms from April 2021 to April 2023 at two outpatient clinics in western Sicily. Our goal was to assess the prevalence of Anisakis-related allergies and to identify risk profiles using specific Anisakis IgE and the BAT, especially in regions with high raw fish consumption. The study evaluated specific Anisakis IgE as a screening tool for Anisakis sensitization, using questionnaires, blood samples, and immuno-allergology analyses. Anisakis-specific IgE values were compared with the BAT results, with statistical analyses including Fisher’s exact test and logistic regression. The results showed an 18.5% seroprevalence of Anisakis IgE, while the BAT as a second-level test showed 4.63%, indicating the BAT’s superior specificity and accuracy. The study highlighted the importance of the BAT in diagnosing Anisakis sensitization, especially in cases of cross-reactivity with Ascaris and tropomyosin. The findings confirm the BAT’s exceptional specificity in identifying Anisakis sensitization and support using Anisakis-specific IgE for population-based risk profiling. The BAT can effectively serve as a confirmatory test. Full article

The rising popularity of undercooked or raw seafood containing larvae of the Anisakis parasite has led to issues of public health concern due to allergic manifestations. We conducted an observational study on the use of an innovative Anisakis allergy diagnostic algorithm in a convenience sample of 53 allergic outpatients recruited in Western Sicily, between April 2021 and March 2022. We included individuals with an anamnesis suggestive of IgE sensitization to Anisakis reporting clinical manifestation in the last month due to allergic reactions after eating fresh fish, or in subjects at high exposure risk with sea products while abstaining from fish ingestion, excluding those with documented fish sensitization. Outpatients were tested via Skin Prick Test, IgE-specific dosage and Basophil Activation Test (BAT). Twenty-six outpatients were diagnosed with Anisakis, while 27 with Chronic Urticaria (CU). We found a seven-fold excess risk for Anisakis (p4) positivity in the Anisakis allergic outpatients, as compared to the CU ones. BAT showed the best diagnostic accuracy (92.45%) and specificity (100%), while specific IgE to Ascaris (p1) documented the best sensitivity (92.31%) but a very low specificity (37.04%). In conclusion, our findings may represent a potentially useful contribution to the future development of updated clinical guidelines. Full article

Fish consumers may develop allergic reactions following the ingestion of fish products containing nematode larvae within the genus Anisakis. Sensitized patients may cross-react with proteins from insects, mites and mollusks, leading to allergic reactions even in the absence of the offending food. Potential cross-reactivity in Anisakis-allergic patients with larval proteins from other zoonotic parasites present in freshwater and sea fish should be investigated due to an increasing occurrence in certain fish stocks, particularly Contracaecum osculatum. In this work, we evaluated IgE-cross reactions by in vivo (skin prick tests with parasites extracts) and in vitro methods (IgE-ELISA and IgE-immunoblot). In vivo skin prick tests (SPT) proved the reactivity of Anisakis-sensitized patients when exposed to C. osculatum antigens. Sera from Anisakis-sensitized patients confirmed the reaction with somatic antigens (SA) and excretory/secretory proteins (ES) from C. osculatum. Only anecdotal responses were obtained from other freshwater worm parasites. Consequently, it is suggested that Anisakis-sensitized humans, especially patients with high levels of specific anti-Anisakis antibodies, may react to C. osculatum proteins, possibly due to IgE-mediated cross-reactivity. Full article

Background: Anisakis simplex (A. simplex) infection, in humans, causes a series of clinical manifestations affecting the gastro-intestinal tract known as Anisakiasis/Anisakidosis. Patients may also present allergic manifestations such as hives and/or angioedema and even anaphylactic shock. The aim of this study was to investigate whether aquacultured fish could be considered A.simplex-free food and constitute a safe, alternative, wild-capture fish food for Gastro-Allergic Anisakiasis (GAA)-sensitized subjects. Methods: Protein extracts from A. simplex larvae in the third stage (L3) and from edible part of heavily infected horse mackerel (Trachurus trachurus) and aquacultured sea bream, have been tested for A. simplex allergens presence by immunological analysis. Western blot analysis using, as source of specific Anisakis allergens antibodies, serum samples from subjects referring allergic symptoms after raw fish ingestion, was performed. These subjects showed high levels of specific IgE anti A.simplex allergens determined by clinical laboratory tests (ISAC test). Results: Our data demonstrate the presence of Ani s4 allergen in both infected and aquacultured fish extracts, providing a possible interpretation for the allergic manifestations reported by subjects, already sensitized to A. simplex, who ate frozen or well-cooked or, even, aquacultured fish. Conclusions: The present data stimulate more accurate prophylaxis suggestions for Anisakis allergy and more specific controls of fishmeal used in aquaculture. Full article