Serum IgA contributes to the comprehension of Anisakis simplex associated chronic urticaria

The phenotype of allergic diseases associated with Anisakis determines the pattern of cytokines related to antibody production. However, the role of serum IgA and the immunomodulatory mechanisms exerted by active infection of L3 or passive mucosal contact with A. simplex specific antigens has not been studied before. We measured serum cytokine by flow cytometry (IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ, IL-17A, TGF-β1) and antibody levels (IgE, IgG4, IgA) by ELISA against total and excretory-secretory (ES) antigens, Ani s 3,and the group of major allergens Ani s 1, Ani s 7, and Ani s 13 in sera from 10 patients with gastro-allergic anisakiasis (GAA), 11 Anisakis sensitization associated chronic urticaria (CU+) as well as 17 non-Anisakis-sensitized patients with chronic urticaria (CU-), compared with the urticaria control group (18 subjects). Specific IgE, IgG4 and IgA were high in the GAA, but IgA levels were significantly higher in the CU+ with respect the CONTROL group. We observed higher levels of the ratio IgA/IgG4 in CU+ than GAA group for Ani s 1, Ani s 7, Ani s 13 and ES. Furthermore, chronic urticaria (CU) patients showed significant lower levels of IL-10, IFN-γ and IL-17A than patients without CU. The anti-Ani s 13 IgA/IgG4 ratio correlated positively with pro-inflammatory cytokines and ratios (TNF-α, IL-17A, Th17/Th2, Type1/Type2 and TNF-α/IL-10) in CONTROL group. In general, Anti-Anisakis IgA/G4 ratio was high in CU patients. In conclusion, this study demonstrates the importance of serum IgA because it is associated with chronic urticaria independently of Anisakis sensitization.

Autoimmune Diseases Are Linked to Type IIb Autoimmune Chronic Spontaneous Urticaria

PURPOSE

Patients with chronic spontaneous urticaria (CSU) have an increased risk for comorbid autoimmune diseases. In this retrospective multicenter study of CSU patients, we evaluated clinical and laboratory features of CSU associated with a higher risk of comorbid autoimmune diseases.

METHODS

We analyzed records of CSU patients (n = 1,199) for a history or presence of autoimmune diseases. Patients were diagnosed with type IIb autoimmune CSU (aiCSU) if all 3 tests were positive: autologous serum skin test (ASST), basophil histamine release assay (BHRA) and/or basophil activation test (BAT), and IgG autoantibodies against FcεRIα/IgE detected by immunoassay.

RESULTS

Twenty-eight percent of CSU patients had at least 1 autoimmune disease. The most prevalent autoimmune diseases were Hashimoto's thyroiditis (HT) (≥ 21%) and vitiligo (2%). Two percent of CSU patients had ≥ 2 autoimmune diseases, most frequently HT plus vitiligo. Comorbid autoimmune diseases, in patients with CSU, were associated with female sex, a family history of autoimmune diseases, and higher rates of hypothyroidism and hyperthyroidism (P < 0.001). Presence of autoimmune diseases was linked to aiCSU (P = 0.02). The risks of having autoimmune diseases were 1.7, 2.9 and 3.3 times higher for CSU patients with a positive ASST, BHRA and BAT, respectively. In CSU patients, markers for autoimmune diseases, antinuclear antibodies and/or IgG anti-thyroid antibodies were associated with non-response to omalizumab treatment (P = 0.013).

CONCLUSIONS

In CSU, autoimmune diseases are common and linked to type IIb autoimmune CSU. Our results suggest that physicians assess and monitor all adult patients with CSU for signs and symptoms of common autoimmune diseases, especially HT and vitiligo.

Biomarkers and clinical characteristics of autoimmune chronic spontaneous urticaria: Results of the PURIST Study

BACKGROUND

Autoimmune chronic spontaneous urticaria (aiCSU) is an important subtype of chronic spontaneous urticaria (CSU) in which functional IgG autoantibodies to IgE or its high-affinity receptor (FcεRI) induces mast cell degranulation and subsequent symptom development. However, it has not been tightly characterized. This study aimed to better define the clinical and immunological features and to explore potential biomarkers of aiCSU.

METHODS

This was a multinational, multicenter study of 182 CSU patients. The clinical features studied included: urticaria activity and impact (UAS7 and quality of life); autologous serum skin test (ASST); IgG anti-FcεRI and IgG anti-IgE; IgG-anti-thyroperoxidase (IgG anti-TPO); total serum IgE; and basophil reactivity (BASO) using the basophil activation test (BAT) and basophil histamine release assay (BHRA).

RESULTS

Of the 182 patients, 107 (59%) were ASST+, 46 (25%) were BASO+, and 105 (58%) were IgG anti-FcεRI+/IgE+. Fifteen patients (8%) fulfilled all three criteria of aiCSU. aiCSU patients appeared more severe (UAS7 21 vs 9 P < 0.016) but showed no other clinical or demographic differences from non-aiCSU patients. aiCSU patients also had markedly lower total IgE levels (P < 0.0001) and higher IgG anti-TPO levels (P < 0.001). Of biomarkers, positive BAT and BHRA tests were 69% and 88% predictive of aiCSU, respectively.

CONCLUSIONS

aiCSU is a relatively small but immunologically distinct subtype of CSU that cannot be identified by routine clinical parameters. Inclusion of BHRA or BAT in the diagnostic workup of CSU patients may aid identification of aiCSU patients, who may have a different prognosis and benefit from specific management.

Characteristics related to fish consumption and the risk of ichthyozoonosis in a Colombian population

Objective This study aimed to determine the dietary habits related to fish consumption and the risk factors associated with acquiring an ichthyo-zoonotic disease.Materials and Methods A descriptive, cross-sectional study was carried out by means of a structured survey administered to 150 individuals in the city of Cali, Colombia.Results Epidemiological variables regarding fish consumption and preparation were contrasted with the medical records of the respondents. The median fish consumption in the surveyed population was three times a month, with raw or salted/marinated fish once a month. A positive correlation between fish consumption and allergic conditions was confirmed. There was no infectious or parasitic history associated with the data on fish consumption.Conclusions A relationship between fish consumption and allergies was confirmed. Further research is necessary to establish the possible pathogens associated with hypersensitivity, such as parasites of the Anisakidae family.

Possible Allergenic Role of Tropomyosin in Patients with Adverse Reactions after Fish Intake

In a recent case report, patient's anti-fish tropomyosin IgE was associated with gastrointestinal symptoms. We aimed to demonstrate on a wider scale that the panallergen tropomyosin should not be limited to invertebrate species and that clinically relevant reactions could be elicited by vertebrate tropomyosin. On the whole, 19 patients with adverse reactions after fish intake and showing negative skin tests with commercial fish extracts were included. Fish tropomyosin was recognized by 10/19 patients' IgE by immunoblotting. All patients with gastrointestinal complaints after fish intake (6/6) showed an IgE band matching with tropomyosin. Cod, albacore, and swordfish tropomyosins were recognized by most patients although 3/10 patients did not claim adverse reactions to these fish species. Immunoblotting with a battery of antigens from different fish species have a high yield of positivity at a band matching with tropomyosin molecular weight, even if they have not been claimed to be causative agents of symptoms. Tropomyosin is therefore a good candidate to be investigated as a clinically relevant fish allergen in patients who report adverse reactions after fish intake.

Recombinant vs native Anisakis haemoglobin (Ani s 13): Its appraisal as a new gold standard for the diagnosis of allergy

Recombinant allergens are currently the best option for serodiagnosis of human anisakiasis in terms of sensitivity and specificity. However, previous reports showed high rates of anisakiasis patients who were negative to Ani s 7 and especially to Ani s 1. Recently, Anisakis haemoglobin was described as a major allergen (Ani s 13). Although Ani s 13 belongs to a conserved protein family, it seems not to be a cross-reacting antigen because of the absence of IgE recognition against Ascaris haemoglobin in Anisakis patients. The aim of this study is to develop a more sensitive and specific diagnosis tool for Anisakis based on the recently discovered allergen Ani s 13. We obtained and purified recombinant Anisakis haemoglobin (rAni s 13) and the native form (nAni s 13). The recognition of both recombinant and native haemoglobins by anti-haemoglobin IgE from patients' sera was assessed by indirect ELISA and immunoblotting using 43 Anisakis sensitised patients and 44 non-Anisakis sensitised patients. Native Ani s 13 was also treated with periodate to study if oxidation of glycans destroys antibody binding. Furthermore, it was structurally characterised by negative staining electron microscopy and analytical ultracentrifugation. Recombinant Ani s 13 was only recognised by four patients with gastro-allergic anisakiasis (GAA) and immunoblotting analyses showed no bands. However, nAni s 13 was detected by 72.1% of Anisakis sensitised patients measured by indirect ELISA. Particularly, 18 (90%) out of 20 GAA patients were positive. Tetramers and octamers were the most abundant homomers of nAni s 13 but octamers had higher content of bound heme. None of the non-Anisakis sensitised patients were positive. Combined use of purified native form of Ani s 13 with current gold standards would improve the sensitivity and specificity for diagnosing anisakiasis.

An Evolutionary-Based Framework for Analyzing Mold and Dampness-Associated Symptoms in DMHS

Among potential environmental harmful factors, fungi deserve special consideration. Their intrinsic ability to actively germinate or infect host tissues might determine a prominent trigger in host defense mechanisms. With the appearance of fungi in evolutionary history, other organisms had to evolve strategies to recognize and cope with them. Existing controversies around dampness and mold hypersensitivity syndrome (DMHS) can be due to the great variability of clinical symptoms but also of possible eliciting factors associated with mold and dampness. An hypothesis is presented, where an evolutionary analysis of the different response patterns seen in DMHS is able to explain the existing variability of disease patterns. Classical interpretation of immune responses and symptoms are addressed within the field of pathophysiology. The presented evolutionary analysis seeks for the ultimate causes of the vast array of symptoms in DMHS. Symptoms can be interpreted as induced by direct (toxic) actions of spores, mycotoxins, or other fungal metabolites, or on the other side by the host-initiated response, which aims to counterbalance and fight off potentially deleterious effects or fungal infection. Further, individual susceptibility of immune reactions can confer an exaggerated response, and magnified symptoms are then explained in terms of immunopathology. IgE-mediated allergy fits well in this scenario, where individuals with an atopic predisposition suffer from an exaggerated response to mold exposure, but studies addressing why such responses have evolved and if they could be advantageous are scarce. Human history is plenty of plagues and diseases connected with mold exposure, which could explain vulnerability to mold allergy. Likewise, multiorgan symptoms in DMHS are analyzed for its possible adaptive role not only in the defense of an active infection, but also as evolved mechanisms for avoidance of potentially harmful environments in an evolutionary past or present setting.

Diamine oxidase levels in different chronic urticaria phenotypes

BACKGROUND

Diamine oxidase (DAO) is a polyamine-degrading enzyme also implicated in histamine metabolism. Chronic urticaria (CU) has a wide spectrum of clinical presentations and causes. Anisakis sensitisation associated chronic urticaria (CU+) has been characterised as a phenotype with different clinical and immunological characteristics and possibly associated with previous acute parasitism. We aimed to analyse serum DAO levels in different CU phenotypes. We further analysed the possible association of DAO with fish eating habits.

METHODS

We studied 35 CU+ patients and 39 non-sensitised CU patients (CU-) as well as 19 controls. We analysed fish-eating frequency as well as fish intake associated exacerbation of CU (FIAE) or gastro-intestinal complaints (GI). DAO levels were further analysed with respect to lymphoproliferative responses, cytokine and specific IgE production.

RESULTS

DAO levels were not different between CU and controls, but were significantly higher in CU+ than in CU-. CU+ patients with FIAE had lower DAO levels, but no differences were detected in patients with GI. DAO levels correlated positively with oily and canned fish consumption in CU-. In CU+, DAO levels correlated positively with specific Anisakis IgE, percentages of proliferation in Anisakis stimulated peripheral blood lymphocytes, serum IL-2 and IL-6, but correlated negatively with mitogen stimulated TGF-β in supernatants.

CONCLUSIONS

DAO levels in CU depend on fish-eating habits and in CU+ on the amount of specific IgE production. In the CU+ phenotype, lower levels of DAO predispose to urticaria exacerbation after fish intake, probably due to a relative insufficient enteric availability of this enzyme.

Haemoglobin, a new major allergen of Anisakis simplex

Gastro-allergic anisakiasis and Anisakis sensitisation associated chronic urticaria are diseases which differ in their IgE and IgG4 responses against both crude extract and specific allergens. Anisakis and Ascaris are closely related nematodes that usually cause problems with specificity in immunodiagnostics. In this study we measured IgE and IgG4 antibodies against Anisakis simplex sensu lato (s. l.) and Ascaris suum haemoglobins in sera of 21 gastro-allergic anisakiasis and 23 chronic urticaria patients. We used a capture ELISA with the anti-Anisakis haemoglobin monoclonal antibody 4E8g, which also recognises Ascaris haemoglobin. In addition, we determined specific IgE and IgG4 to both nematodes by indirect ELISA and immunoblotting. Anti-A. simplex s. l. haemoglobin IgE and IgG4 levels were higher in gastro-allergic anisakiasis than in chronic urticaria patients (P=0.002 and 0.026, respectively). Surprisingly, no patient had detectable IgE levels against A. suum haemoglobin. Finally, we carried out an in silico study of the B-cell epitopes of both haemoglobin molecules. Five epitopes were predicted in Anisakis pegreffii and four in A. suum haemoglobin. The epitope propensity values of Anisakis haemoglobin in the equivalent IgE binding region of the allergenic haemoglobin Chi t 1 from Chironomus thummi, were higher those of the Ascaris haemoglobin. In conclusion, we describe A. simplex haemoglobin as a new major allergen (Ani s 13), being recognised by a large number (64.3%) of sensitised patients and up to 80.9% in patients with gastro-allergic anisakiasis. The presence of a specific epitope and the different values of epitope propensity between Anisakis and Ascaris haemoglobin could explain the lack of cross-reactivity between the two molecules. The absence of IgE reactivity to Ascaris haemoglobin in Anisakis patients makes Anisakis haemoglobin (Ani s 13) a potential candidate for developing more specific diagnosis tools.

Management of angioedema without urticaria in the emergency department

Angioedema refers to a localized, transient swelling of the deep skin layers or the upper respiratory or gastrointestinal mucosa. It develops as a result of mainly two different vasoactive peptides, histamine or bradykinin. Pathophysiology, as well as treatment, is different in each case; nevertheless, the resulting signs and symptoms may be similar and difficult to distinguish. Angioedema may occur at any location. When the affected area involves the upper respiratory tract, both forms of angioedema can lead to an imminent upper airway obstruction and a life-threatening emergency. Emergency physicians must have a basic understanding of the pathophysiology underlying this process. Angioedema evaluation in the emergency department (ED) should aim to distinguish between histamine- and bradykinin-induced angioedema, in order to provide appropriate treatment to patients. However, diagnostic methods are not available at the ED setting, neither to confirm one mechanism or the other, nor to identify a cause. For this reason, the management of angioedema should rely on clinical data depending on the particular features of the episode and the patient in each case. The history-taking should be addressed to identify a possible etiology or triggering agent, recording complete information for an ulterior diagnostic study in the outpatient clinic. It is mandatory quickly to recognize and treat a potential life-threatening upper airway obstruction or anaphylaxis. This review focuses on the underlying mechanisms and management of histamine- and bradykinin-induced angioedema at the emergency department and provides an update on the currently available treatments.

Characterisation of potential novel allergens in the fish parasite Anisakis simplex

The parasitic nematode Anisakis simplex occurs in fish stocks in temperate seas. A. simplex contamination of fish products is unsavoury and a health concern considering human infection with live larvae (anisakiasis) and allergic reactions to anisakid proteins in seafood. Protein extracts of A. simplex produce complex band patterns in gel electrophoresis and IgE-immunostaining. In the present study potential allergens have been characterised using sera from A. simplex-sensitised patients and proteome data obtained by mass spectrometry. A. simplex proteins were homologous to allergens in other nematodes, insects, and shellfish indicating cross-reactivity. Characteristic marker peptides for relevant A. simplex proteins were described.

New insights into the allergenicity of tropomyosin: a bioinformatics approach

The invertebrate panallergen tropomyosin is a protein with an extremely simple folding. This makes it a perfect target for investigating structural differences between invertebrate and vertebrate tropomyosins, which are not considered allergenic. Phylogenetic and sequence analyses were conducted in order to explore the differences in primary structure between several tropomyosins and to promote an experimental development in the field of food allergy, based on the study of tropomyosin. The phylogenetic analyses showed that tropomyosin is a useful evolutionary marker. The phylogenetic trees obtained with tropomyosin were not always phylogenetically correct, but they might be useful for allergen avoidance by tropomyosin allergic individuals. Sequence analyses revealed that the probability of alpha helix folding in invertebrate tropomyosins was lower than in all the studied vertebrate ones, except for the Atlantic bluefin tuna Thunnus thynnus tropomyosin. This suggested that the lack of alpha helix folding may be involved in the immunogenicity of tropomyosins. More specifically, the regions adjacent to the positions 133-135 and 201 of the invertebrate tropomyosins, presented lower probability of alpha helix folding than those of vertebrates and are candidates to be responsible for their allergenicity.

Different fish-eating habits and cytokine production in chronic urticaria with and without sensitization against the fish-parasite Anisakis simplex

BACKGROUND

Anisakis simplex sensitization has been associated with acute, but also with chronic urticaria. The objective of this study is to characterize chronic urticaria with (CU+) and without sensitization (CU-) against the ubiquitous fish parasite A. simplex in a transversal and longitudinal evaluation.

METHODS

16 CU+ and 22 CU- patients were included and assessed for Urticaria activity score (UAS), fish-eating habits by standardized questionnaire and cytokine production (assessed by flow cytometric bead-based array) of peripheral blood mononuclear cells after stimulation with A. simplex extract or Concanavalin A (Con A). Patients were randomly put on a fish-free diet for three months and UAS, as well as cytokine production were again assessed. A difference of ≥1 in UAS was defined as improvement.

RESULTS

There was no difference in UAS in both groups. Anisakis induced IL-2, IL-4 and IFN-γ production was higher in CU+. Con A induced IL-6 and IL-10 production was higher in CU+. CU+ was associated with higher total fish intake, whereas CU- was associated with oily fish intake. The correlation of UAS was positive with oily fish, but negative with total fish intake. There was a better UAS-based prognosis in CU+ without diet. Improvement was associated with higher Con A induced IL-10/IFN-γ as well as IL-10/IL-6 ratios. Further, previous higher oily fish intake was associated with improvement.

CONCLUSIONS

Our data confirm the different clinical and immunological phenotype of CU+. Our results show a complex relationship between fish-eating habits, cytokine production and prognosis, which could have important consequences in dietary advice in patients with CU. When encountering A. simplex sensitization, patients should not be automatically put on a diet without fish in order to reduce contact with A. simplex products.

Ani s 1 and Ani s 7 recombinant allergens are able to differentiate distinct Anisakis simplex-associated allergic clinical disorders

Diagnosis in gastro-allergic anisakiasis (GAA) is straightforward, when clinical history is combined with further allergological evaluation of specific IgE by means of skin prick test and serum specific IgE. In Anisakis simplex sensitisation associated chronic urticaria (CU+), clinical evaluation of possible previous parasitism is difficult, and positive serum specific IgE could be due to cross-reactivity or other unknown factors. In this study, we evaluated the association between IgE seropositivity to the recombinant allergens Ani s 1 and Ani s 7 and several A. simplex-associated allergic disorders. Twenty-eight patients with GAA and 40 patients with CU+ were studied and their IgE responses were compared with a control group composed of patients with chronic urticaria not sensitized to A. simplex (CU-) according to the skin prick test, as well as a group of 15 healthy subjects not referring urticaria or currently A. simplex associated symptoms. 82.1% of GAA patients and 42.5% of CU+ patients were positive for Ani s 1 (P < 0.001), while the Ani s 7 allergen was recognized by 92.9 and 92.5% of sera from patients with GAA and CU+, respectively. The combined positivity obtained for both allergens reached 100% in GAA, and 95% in CU+. IgE determinations to Ani s 1 and Ani s 7 allergens are useful to diagnose the Anisakis infections and to differentiate among several A. simplex-associated allergic disorders. The IgE responses to Ani s 1 are mainly associated with GAA, while this molecule cannot be considered a major allergen in CU+ patients.

Different serum cytokine levels in chronic vs. acute Anisakis simplex sensitization-associated urticaria

The knowledge on immune mechanisms of chronic urticaria (CU) at the cytokine level is widely scarce. We compared pro- and anti-inflammatory as well as Th1- and Th2-associated serum cytokine levels in two phenotypes of CU: associated with (CU+) and without (CU⁻) sensitization against Anisakis simplex, a ubiquitous fish parasite, that has been associated with acute urticaria in gastro-allergic anisakiasis (GAA) and with CU+. Thirteen CU+ and 19 CU⁻ patients were compared with 13 GAA patients and 15 control subjects for cytokines, measured by cytometric bead array. Urticaria activity score was positively correlated with IL-6 in CU⁻. Serum levels of IL-10 were lower in CU+ and CU⁻ with respect to the control group. Median IFN-γ was lower in all urticaria groups. Patients with previous parasitism by A. simplex displayed higher TGF-β levels than subjects without previous parasitism. The main finding was lower levels of IL-17 in CU+ with respect to GAA or controls, with a further tendency to even lower levels in CU⁻. Different urticaria phenotypes are associated with distinct serum cytokine levels.

Chronic urticaria is associated with a differential helminth-arthropod-related atopy phenotype

The relationship between atopic sensitization and chronic urticaria is still controversial. In this study, we aimed to compare the prevalence of aeroallergen sensitization in chronic urticaria patients with (CU/As+) and without (CU/As-) sensitization against Anisakis simplex. Forty-nine CU/As+ and 80 CU/As- patients were studied and skin prick tests (SPT) were performed against aeroallergens. We assessed sensitization in a subgroup of patients with allergic rhinoconjunctivitis and/or bronchial asthma (RCBA) and compared the prevalence with a control group of 522 non-urticaria patients with RCBA. Forty-five percent of CU/As- and 60.4% of CU/As+ patients displayed positive SPT to at least one aeroallergen. CU/As+ patients had a higher prevalence of sensitization against pollen, mould or dander (PMD) (52.2% vs 29.1%, P < 0.01), whereas the prevalence of house dust mite (HDM) sensitization was not statistically different (26.3% in CU/As- and 36.7% in CU/As+). However, in chronic urticaria patients with RCBA, 53.8% of CU/As- and 57.9% of CU/As+ patients differed in the prevalence of HDM sensitization compared to the control group (33.5%, P = 0.03), whereas no difference could be stated for PMD sensitization. Compared to RCBA patients, both CU/As+ and CU/As- patients have a higher clinically relevant sensitization rate against HDM, thus displaying a differential atopy phenotype.

The hidden sense of symptoms: urticaria can be beneficial

Evolutionary Medicine can be useful when analysing the origin of disease and symptoms. Acute urticaria or anaphylaxis is bothersome and potentially life-threatening. We analyse this symptom-complex in the context of Gastro-allergic Anisakiasis (GAA), where the human is an incidental host for the cosmopolitan fish-nematode Anisakis simplex (A. simplex). The immunological response against this nematode resembles that against other helminths, but overt expression of allergic symptoms is by far more frequent in GAA. This could be due to the missing co-evolutionary relationship between host and parasite. Features of acute gastric parasitism with and without overt allergic type 1 hypersensitivity symptoms are compared with the abdominal complications in intestinal Anisakiasis, where clinically visible IgE mediated symptoms are missing. In GAA, parasite induced chronic abdominal complications are missing. We postulate that urticaria in GAA can be considered the price for rapidly expelling the live larva of A. simplex in those subjects whose evolutionary history made them more resistant to other helminth parasites. Further, urticaria is explained as a possibly exaggerated immunopathological feature in this special type of acute parasitism, where sensitized mast-cells are not only present in the skin, but also in the gastro-intestinal mucosa. This evolutionary analysis of clinical observations is the first known report that addresses the possible beneficial feature of hypersensitivity type 1 response with overt allergic urticaria-anaphylaxis in GAA and confers an evolutionary based sense to the acute IgE-mediated reaction.

Towards a differential definition of atopy: Anisakis simplex and the relationship between parasites and arthropods in respiratory allergy

Protective as well as enhancing effects of parasite infections on allergic disease have been postulated. Previous studies on this relationship focused frequently on skin test reactivity against aeroallergens, being house dust mites (HDM) the main agents responsible for a positive atopy outcome. We aimed to analyse the possible relationship between human parasite infection induced Anisakis simplex urticaria and respiratory allergy. A total of 86 patients with gastro-allergic Anisakiasis and 203 patients with chronic urticaria sensitized against A. simplex were studied for sensitization against aeroallergens and evaluated for rhinoconjunctivitis or bronchial asthma (RCBA). We compared the results with a control group of 250 consecutive patients referred for evaluation of allergic RCBA and atopy prevalence data of our region. Whereas no effect of A. simplex related disease on the overall allergic respiratory disease could be detected, a highly significant higher prevalence of RCBA associated HDM sensitization, but diminished allergy against other common aeroallergens (pollen, mould or dander) was observed in these groups. The relationship between A. simplex parasitism-associated acute or chronic urticaria on one side and allergic respiratory disease on the other side depends on the definition of atopy. We propose a differential definition of atopy, with a special emphasis on arthropod related sensitization.

Anisakis simplex: sensitization and clinical allergy

PURPOSE OF REVIEW

Whereas gastric anisakiasis has been known for several decades, the implications of Anisakis simplex-related allergic disorders had not been thoroughly studied until the late 1990s. This article reviews recent knowledge of allergic disorders ascribed to A. simplex contact or parasitism.

RECENT FINDINGS

Gastroallergic anisakiasis describes an acute hypersensitivity reaction emerging in the context of an acute parasitism by the nematode A. simplex. But other frequent allergic disorders like chronic urticaria are now being studied for a possible relationship with A. simplex parasitism. In recent investigations, non-IgE mediated mechanisms, such as the involvement of other immunoglobulin isotypes (IgG4), or non-immunological events are discussed.

SUMMARY

The experience of the last several years shows that allergic hypersensitivity symptoms in gastroallergic anisakiasis are clinical events accompanying a wide range of immunologic reactions as a host response against a ubiquitous parasite. The discussed and reviewed studies should motivate allergists around the world to search for this entity. Further studies in the field of allergy could benefit from the experience of this peculiar food-related disorder.

Allergy and parasites reevaluated: wide-scale induction of chronic urticaria by the ubiquitous fish-nematode Anisakis simplex in an endemic region

BACKGROUND

The ubiquitous fish-nematode Anisakis simplex produces acute urticaria or angioedema in the course of gastro-allergic anisakiasis. We studied the relationship between this nematode and chronic urticaria (CU), as well as the clinical usefulness of measuring specific IgG4 in A. simplex-sensitized patients with CU.

METHODS

First, the prevalence of sensitization to A. simplex was estimated in 135 consecutive CU patients and the result was compared with known data about sensitization in a healthy population. Then, clinical response to a 2-month diet without fish was analyzed in 76 CU patients. The improvement rate in patients with and without sensitization to A. simplex was compared. Finally, the improvement rate, other clinical data and specific immunoglobulins in sensitized patients with and without detectable specific IgG4 were compared.

RESULTS

a) The A. simplex sensitization rate in CU patients was 52.6 % compared with a known prevalence of between 16 and 20 % in our region. b) Of 65 sensitized patients, 52 experienced clinical improvement after the diet compared with only three of 11 patients without sensitization to A. simplex (p = 0.001). c) Of 43 patients with detectable specific IgG4, 38 showed clinical improvement compared with only 14 of 22 patients without detectable IgG4 (p = 0.02). Eight of nine patients with previous fish-associated cutaneous symptoms had detectable specific IgG4 compared with 15 of 32 patients who reported no previous fish-associated symptoms or acute urticaria (p = 0.03).

CONCLUSIONS

Our results indicate that A. simplex is a possibly widespread etiologic agent able to induce CU. This parasite model constitutes the first report that associates an infectious agent with CU on a large scale. The detection of IgG4 antibodies reflects a previous acute parasitic infection and a temporary diet without fish improves symptoms in most patients with detectable specific IgG4.

Anisakis simplex only provokes allergic symptoms when the worm parasitises the gastrointestinal tract

We analysed patients with allergic or digestive symptoms after seafood ingestion in order to assess a correct diet in Anisakis simplex sensitised individuals. A total of 120 patients who suffered allergic and/or digestive symptoms after marine food ingestion were studied. We performed skin prick tests for A. simplex and seafood, total serum and specific serum immunoglobulin E to A. simplex in the acute stage and 1 month later. A gastroscopy was carried out to find larvae in those patients with persistent abdominal pain. A challenge with non-infective larvae was performed to assess a correct diet. Some 96 patients were sensitised to A. simplex. Gastroscopy was performed in 47 and we detected larvae in 24. We compared symptoms, skin tests, total and specific IgE and the latency of appearance of symptoms in patients positive for Anisakis larvae, patients without larvae at gastroscopy and patients without digestive symptoms. There was no difference among the groups. We challenged 22 patients with frozen A. simplex larvae. After allowing deep-frozen seafood in the diet for more than 2 years, no patient suffered a reaction. At this time, we allowed all our patients well-frozen seafood without any allergic reaction occurring. Allergic symptoms are the most frequent manifestation of A. simplex parasitism. We could not find any patient allergic to the thermostable proteins of parasite.

Gastro-allergic anisakiasis as a consequence of simultaneous primary and secondary immune response

Gastro-allergic anisakiasis has been reported as an entity in which an acute parasitism by Anisakis simplex is accompanied by an immunoglobulin (Ig)E-mediated systemic allergic reaction. Serum samples were obtained from 24 patients within 24 h after the onset of symptoms (day 0) and after 1 month (day 30) and in 13 patients after 6 months. Total IgE was assessed by the Imx method. Specific IgE was assessed by CAP-FEIA. Specific IgM, IgG, IgG4 and IgA antibodies were assessed by enzyme-linked immunosorbent assay against crude extract (CE) and excretory-secretory products (ESP). IgE immunoblotting (IB) was directed against CE or ESP (day 0 and day 30). We found a rise of total IgE, specific IgE, number of bands in IgE-IB, IgG and IgG4 between day 0 and day 30 with a fall to near basal levels after 6 months. IgM levels were highest at day 0, falling over the next 6 months and IgA levels remained almost unchanged. Correlation studies revealed a parallel stimulation of nearly all Ig isotypes, except IgM anti-ESP, whose antibody levels correlated negatively with specific IgG levels. We found an extension of the IgE antibody repertoire in IB. We conclude that the allergic IgE-mediated reaction in the course of gastro-allergic anisakiasis involves a parallel secondary Th2 type memory response and a primary immunologic stimulation of both Th2 and Th1 lymphocyte subsets against previously unrecognized antigens.

Serum CD23 is not altered in gastroallergic anisakiasis, but correlates with the production of specific IgE and the amount of polyclonal stimulation

BACKGROUND

Previous studies have shown elevated serum levels of the cytokines IL-4 and sCD23 in atopic patients and parasitic disease. Gastroallergic anisakiasis is an acute parasitic disease, accompanied by IgE-mediated clinical symptoms and an important increase of specific and total IgE.

METHODS

Sixteen patients with acute urticaria/angioedema due to parasitism by Anisakis simplex after intake of raw or undercooked fish were selected, and serum samples were taken in the emergency room within 24 h (day 0; n=16), after 1 month (n=16), and after 6 months (n=10). Serum samples were studied for specific IgE against A. simplex, total IgE, sCD23, and IL-4.

RESULTS

Mean values for sCD23 did not change in the observation period. Only 4/16 serum samples showed measurable IL-4 levels. Specific IgE and total IgE levels were found to be elevated after 1 month; after 6 months, they fell to nearly basal values. There was a positive correlation between sCD23 and specific IgE at day 0 and follow-up (r=0.55-0.69, P<0.026); a positive correlation between sCD23 and total IgE (r=0.54-0.62, P<0.056). Basal sCD23 could moderately predict the percentual increment of total IgE in the first month (r=0.56, P<0.038).

CONCLUSION

Thus, it seems that interindividual variability of sCD23 is an important factor, with higher values predisposing to more production of unrelated IgE, independently of the parasite's action.

Gastroallergic anisakiasis: findings in 22 patients

BACKGROUND AND AIMS

Ingestion of Anisakidae larvae in raw seafood may cause anisakiasis. However, despite the high level of consumption of seafood in Spain, only a few cases of anisakiasis have been reported until now. Anisakis simplex can cause allergic reactions in sensitized patients as a result of its parasitism in the gastrointestinal tract. The purpose of this study was to analyse the clinical findings in 22 patients with gastroallergic anisakiasis.

METHODS

Patients with allergic and/or gastric symptoms after seafood ingestion were evaluated in the emergency room of the La Paz General University Hospital. Skin testing for Anisakis simplex and tests on the implicated seafood were performed and amounts of serum-specific immunoglobulin E were assessed. A gastroscopy was performed in those patients with severe allergic or/and persistent gastric symptoms after ingestion of raw or undercooked seafood.

RESULTS

Twenty-two patients were diagnosed with gastroallergic anisakiasis in 1 year. Most patients presented to the emergency room of our hospital with allergic symptoms. Gastric symptoms were usually moderate. Gastroscopy revealed local mucosal oedema and gastric erosion at the point of fixation. Two or more worms were detected in three patients. The mean time of latency of allergic symptoms was 5 h, while the mean time for gastric symptoms was 3 h.

CONCLUSION

Anisakis simplex parasitism was the causative agent of allergic and gastric symptoms. Gastroallergic anisakiasis appears to be a relatively common disease, that may have been underdiagnosed.

What does Anisakis simplex parasitism in gastro-allergic anisakiasis teach us about interpreting specific and total IgE values?

BACKGROUND

gastro-allergic Anisakiasis is a mostly transitory clinical entity caused by Anisakis simplex (A. simplex) and can be suspected by history and confirmed by fiberoptic gastroscopy and specific IgE.

OBJECTIVE

we report a case of gastro-allergic Anisakiasis, in which the parasite induces a high specific and total IgE response, and want to follow the specific and total IgE values by a serologic follow up over 10 months.

METHODS

an analysis of total IgE and specific IgE against. A. simplex was performed within 24 hours, after 1, 4, 6 and 10 months. At month 4 and month 10 specific IgE against Ascaris lumbricoides and Echinococcus granulosus was determined in order to value cross-reactivity.

RESULTS

there is an important raise in specific IgE against Anisakis simplex (up to 903 kU/l) after 6 months and total IgE (up to 15,258 kU/l) after one month. Cross-reactive specific IgE against Ascaris lumbricoides and Echinococcus granulosus can be detected.

CONCLUSIONS

we consider a raise of total and specific IgE as a typical feature of helminth infestation and learn that specific and total IgE values are highly variable in the months following the allergic and parasite-specific reaction. The amount of specific IgE against other cross reactive parasites depends directly on the total IgE values.

Gastroallergic anisakiasis: borderline between food allergy and parasitic disease-clinical and allergologic evaluation of 20 patients with confirmed acute parasitism by Anisakis simplex

BACKGROUND

Human subjects can be parasitized by Anisakis simplex by eating raw or undercooked fish. Gastric anisakiasis is probably the most frequent clinical entity presenting with severe epigastric pain, vomiting, and diarrhea. In gastroallergic anisakiasis hypersensitivity symptoms predominate.

OBJECTIVE

We sought to describe clinical features, laboratory data, and gastroscopic findings in gastroallergic anisakiasis.

METHODS

We selected 40 patients presenting to the emergency department with an acute allergic reaction, and if we suspected acute parasitism by A simplex, a fiberoptic gastroscopy was performed. In 20 patients we could detect one or more nematodes; these patients are referred to as group A. Those in whom no worm could be found are referred to as group B (n = 20). A detailed history, clinical features, gastroscopic findings, laboratory data, and skin prick test responses were compared.

RESULTS

Long-time intervals of up to 26 hours between fish intake and onset of hypersensitivity symptoms were found (group A, 5.4 +/- 6.3 hours; group B, 5.3 +/- 2.6 hours). Patients in groups A and B did not differ with respect to allergic symptoms (urticaria, angioedema, erythema, bronchospasm, and anaphylaxis) or the mainly light abdominal symptoms (upper abdominal pain, nausea, vomiting, and diarrhea). No significant differences were found with respect to age, time interval between fish intake and onset of symptoms, white cell and eosinophil counts, specific IgE levels against A simplex, or total IgE levels.

CONCLUSIONS

The peculiar sometimes long-time interval between fish intake and onset of allergic symptoms render the diagnosis difficult. An early gastroscopy can confirm the diagnosis and prevent complications. We suggest that gastroallergic anisakiasis be considered a distinct clinical entity in which the predominant symptoms are hypersensitivity symptoms and in which the correct diagnosis is not only important in the management of the acute reaction but also in the prevention of further allergic episodes.

Usefulness of early serial measurement of specific and total immunoglobulin E in the diagnosis of gastro-allergic anisakiasis

BACKGROUND

Sensitization to Anisakis simplex (A. simplex) has been documented to produce severe allergic reactions following ingestion of mainly raw or under-cooked parasitized fish. False positive skin prick tests (SPT) or specific IgE against this nematode and cross-reactivity restricts diagnosis. Gastric anisakiasis and gastro-allergic anisakiasis occur if fish is parasitized by live A. simplex

OBJECTIVE

To investigate if serial serological analysis could be useful in the diagnosis of acute parasitation by this nematode.

METHODS

We included 41 patients who experienced an allergic reaction and/or abdominal symptoms after ingestion of raw or undercooked fish and displayed specific IgE against A. simplex. Total and specific IgE were determined two times: in the 24-h period after onset of clinical symptoms and after 1 month. SPTs were performed against A. simplex and implicated fish. A fibre optic gastroscopy was performed in 22 patients.

RESULTS

Median total IgE was 80.0 (Interquartile range [IQR] 41.5-186.5) kU/L in the first evaluation and 247.0 (IQR 96.5-649.5) kU/L after 1 month. Median specific IgE against A. simplex was 11.4 (IQR 7.1-33.5) kU/L in the first 24 h and 36.8 (IQR 19.5-79.5) kU/L after 1 month. A rise of total IgE was observed in 35 of 41 patients (P<0.00001) and a rise in specific IgE against A. simplex in 37 of 41 patients (P<0.00001). Mean percentage increment was 392% (215-571%; 95% confidence interval [CI]) for total IgE and 339% (177-502%; 95% CI) for specific IgE. In nine of 22 gastroscopic examinations at least one larva, identified as A. simplex, could be detected by our microbiology service. In this group (n = 9) a rise of total and specific IgE was detected in eight patients (89%) (P = 0.02).

CONCLUSIONS

We consider a rise of total and specific IgE in the first month after an allergic reaction as a useful tool in the diagnosis of gastro-allergic anisakiasis (together with patient's history), even if the parasite cannot be seen with fibre optic gastroscopy. The important rise of total and specific IgE against A. simplex can be considered as a reaction induced by the live parasitizing larva in the context of a polyclonal immunological stimulation.

Dietary assessment in five cases of allergic reactions due to gastroallergic anisakiasis

BACKGROUND

Anisakis simplex can cause allergic reactions in sensitized patients. Some of these reactions are related to acute parasitism, as is shown in gastroallergic anisakiasis (anisakiasis with digestive and predominantly allergic symptoms). At present, a nonseafood diet is recommended for all patients with any kind of A. simplex allergy. We wished to confirm the clinical suspicion that patients with allergic symptoms after ingestion of raw or undercooked seafood who are sensitized to A. simplex, and diagnosed with gastroallergic anisakiasis, can tolerate the ingestion of seafood when the parasites are dead and noninfective.

METHODS

We included patients diagnosed with gastroallergic anisakiasis (positive skin prick test or/and serum specific IgE to A. simplex, with one or more parasites found by gastroscopy in the stomach). Patients included in the study gave written, informed consent. Specimens of A. simplex about 2 cm long were selected, placed in capsules, and frozen at -20 degrees C for more than 48 h to make them noninfective. We administered 11 specimens to every patient at the hospital. If they tolerated the larvae, they were told to eat well-frozen seafood (-20 degrees C at least 48 h). After 6 months, the patients were re-evaluated.

RESULTS

Five patients accepted the challenge with noninfective A. simplex larvae. All tolerated the noninfective larvae. After eating deep-frozen seafood for 6 months, no patient suffered a reaction.

CONCLUSIONS

In gastroallergic anisakiasis, the antigens of the live parasite probably cause the allergic symptoms. Patients with this disease can tolerate deep-frozen seafood, in which the parasites are dead.

Gastric anisakiasis: an underestimated cause of acute urticaria and angio-oedema?

Acute urticaria and angio-oedema are common in primary care and in the emergency unit. Food allergy is one possible cause. We describe gastric anisakiasis, in which symptoms are often not obviously related to eating raw fish. A study was made of patients presenting at the emergency department who had allergic symptoms such as urticaria or angio-oedema and had recently eaten raw or undercooked fish. They were divided into two groups. Patients in group A (n = 13) also had abdominal symptoms and were diagnosed as having gastric anisakiasis by fibre-optic gastroscopy where third-stage larvae of Anisakis simplex were visualized and extracted. Skin prick tests and specific IgE to A. simplex were positive. Patients in group B (n = 13) had only allergic symptoms after eating raw fish. Eleven of 13 patients had positive skin prick tests and specific IgE to A. simplex. Three of 15 control subjects had positive skin prick tests and specific IgE to A. simplex. Allergic symptoms appeared from 2 to 20 h (mean 5.0) after ingestion in group A and from 20 min to 23 h (mean 4.3 h) in group B. Gastric symptoms in group A disappeared rapidly after extraction of the larvae. Allergic symptoms disappeared in most cases within the first 24 h. We suggest that the allergic symptoms in group A as well as in group B were mainly due to parasitization by A. simplex in sensitized patients. Gastric anisakiasis may be a widely underdiagnosed clinical entity.

Specific IgE to recombinant vegetal panallergen (rBet v 2) and fruit allergy in pollinic patients

The presence of IgE antibodies to the allergens rBet v 1 and rBet v 2 was investigated in patients with known sensitization to ryegrass (Lolium perenne) and/or olive (Olea europaea) pollen, by comparing a group of 10 patients who had allergic symptoms after ingestion of fruits (A) with a group of 17 patients who had only seasonal respiratory symptoms (B). There was no significant difference between the two groups for total IgE. All patients showed specific IgE to both L. perenne and O. europaea. No specific IgE binding to rBet v 1 was detected in any patient. The incidence of the presence of IgE antibodies to rBet v 2 was 90% in the group with fruit allergy (A) and 35% in group B. We found a significant association between presence of IgE antibodies to rBet v 2 and fruit allergy (P = 0.007). Specific IgE values to O. europaea pollen were higher in the fruit-allergy group than the group without fruit allergy (P = 0.032). In conclusion, pollen-allergic patients with specific IgE to birch pollen profilin show a significantly elevated frequency of fruit allergy.

Exposure to parakeets and bronchiolitis obliterans

Case report of a 64-year-old woman with increasing dyspnea and cough. She cared at home for 8 parakeets (Melopsittacus undulatus). Subsequent studies revealed a restrictive pulmonary defect and transbronchial biopsy, a histological bronchiolitis obliterans (BO). No significant elevated anti-avian IgG could be detected, probably because of a transient hypogammaglobulinaemia. The implication of antigenic exposure to avian antigens in the pathogenesis of BO is discussed.

Natural variation in mite antigen density in house dust and relationship to residential factors

To investigate the year-to-year variation of mite antigen density (Der p I, Der fI) in dust from mattresses and the relevance of residential factors for antigen load, information derived from an epidemiologic study including two surveys carried out in the households of a cohort of elementary school children (n = 1291) was analysed. When considering residences with measurements taken in both years in question (n = 1050), rank-correlation indicated a predominance of stability for both antigens (Der p I: rs = 0.82, P = 0.0001; Der f I: rs = 0.72, P = 0.0001). Using multiple regression analyses, significant associations between antigen concentrations and a variety of residential factors were found. Use of a blanket of animal hair, use of a cover or underblanket, wet spots in the bedroom, higher relative humidity and a low storey level were significantly associated with increased concentrations of Der p I, whereas inverse relationships between this antigen and room temperature, number of persons per m2 as well as use of underfloor heating were seen. Regarding Der fI, older mattresses, use of a cover or underblanket, higher weight of sampled dust, high educational level and higher ratio of inhabitants per m2 were significantly associated with increased concentrations of the antigen. On the other hand, lower Der fI concentrations were found when interior sprung mattresses were used and when the mattress was 'treated regularly'. In conclusion, two measurements, 1 year apart from each other, show that stability of mite antigen concentrations predominated.(ABSTRACT TRUNCATED AT 250 WORDS)