Mackerel-induced urticaria and Anisakis

IgE-mediated Anisakis allergy in children

Anisakids are nematodes responsible for different clinical patterns in humans. The well-known human-infecting Anisakis species include members of the Anisakis simplex (AS) complex. Humans usually contract anisakiasis through ingestion of raw or undercooked seafood containing Anisakis larvae. Once Anisakis has been ingested, patients may develop disease driven directly by Anisakis larvae and/or by allergic reaction due to this nematode. The capability of inducing allergic reactions depends on the expression of specific antigens by nematodes and host factors. This study aims to resume actual knowledge about AS and Anisakiasis with regard to epidemiology, pathophysiology, clinical presentation, diagnosis, and treatment. Particular attention is paid to Anisakis allergens and their cross-reactivity on available diagnostic methods, and defining a diagnostic pathway for Anisakis allergy. Because only a few data are available in the literature about pediatric population, we focus on this group of patients specifically.

Association between anti-Anisakis simplex antibodies and interleukin-7 levels

IL-7 is a crucial factor for the development of lymphocytes, and it is absolutely necessary for γδ T cells. Mice deficient in L-7 have a deficit of B and αβ T lymphocytes, and an absence of mature γδ TCR cells. IL-7 is essential for the survival, development and maturation of Schistosoma sp., although its production is associated with protection against intestinal helminths. The presence of anti-Anisakis simplex antibodies, especially IgA, is related to a lower frequency in CD3 + CD56 + αβ + lymphocytes and all subpopulations of γδ T cells. In this work, the relationship of IL-7 with humoral and cellular responses against A. simplex in 100 healthy subjects was studied. We have found significantly higher IL-7 levels in anti-A. simplex IgA-positive subjects (p < 0.001). The positivity of anti-A. simplex IgA was associated with a significant reduction in the frequency of CD3 + αβ+ (p < 0.01), CD3 + CD4 + αβ+, CD3 + CD8 + αβ+, CD3 + CD56 + αβ+, CD3 + γδ+, CD3 + CD4-CD8-γδ+ and CD3 + CD56 + γδ+ (p < 0.05) cells. In the case of NKT cells, this same phenomenon was also associated with IgE positivity. There was a weak inverse correlation (Spearman) of IL-7 levels with the frequencies of CD3 + CD4 + αβ+ (-0.125, p = 0.047), CD3 + CD8 + αβ+ (-0.204, p = 0.032), CD3 + CD56 + αβ+ (-0.247, p = 0.007), CD3 + γδ+ (-0.267, p = 0.007), CD3 + CD4-CD8-γδ+ (-0.266, p = 0.003), and CD3 + CD8 + γδ + (-0.302, p = 0.002) cells. The role of NKT cells in the anti-A. simplex response was confirmed and an association between IL and 7 levels and specific antibodies, especially IgA, was demonstrated. The higher production of IL-7 would represent a compensatory mechanism in response to the reduction in lymphocyte populations associated with the response against this parasite.

Anisakis, Something Is Moving inside the Fish

The first case of human infection by a species of the Anisakidae family was reported more than 60 years ago. Over the last 20 years, Anisakis has become a highly studied parasite, not only for its parasitism, but also for its role as an inducer of allergic reactions. Several studies have indicated that the pathological changes occurring within the gastrointestinal tract during infection with Anisakis simplex are the combined result of the direct action of the larvae invading the tissue and the complex interaction between the host’s immune system and the parasite. Although the most commonly described pathologies are digestive, urticaria/angioedema and anaphylaxis, occupational asthma and arthritis have been seldom described. This paper is a narrative of the immune-mediated reaction induced by this parasite over the course of the last two decades.

Effectiveness of Gutting Blue Whiting (Micromesistius poutassou, Risso, 1827), in Spanish Supermarkets as an Anisakidosis Safety Measure

Anisakidosis is a parasitic zoonotic disease which can cause gastroallergic reactions in humans. In 2010, the European Food Safety Agency estimated that approximately 20,000 cases of anisakiasis had been reported across the world, with Spain having the highest number of infections in Europe. The blue whiting (Micromesistius poutassou, Risso, 1827) is one of the most widely fished species worldwide and represents around 25% of the white fish eaten in Spain. The Spanish Food Safety Authority requires obligatory evisceration of certain fish species before commercialization, but not for blue whiting. Nevertheless, some supermarkets carry this out themselves to prevent human infections and negative customer reactions deriving from the presence of ascaridoid larvae. To assess the effectiveness of eviscerations at supermarkets, a total of 320 blue whiting specimens were examined. The risk of larval migration from the visceral cavity to the musculature in gutted and ungutted fish was also assessed. Our results showed a total prevalence (25%) of ascaridoids in fish gutted at the supermarket, and a direct relationship was found between the presence of larvae in the muscle and time until evisceration. In ungutted fish, the standard length and weight were higher for infected than for non-infected fish. Also, massive infections had a higher prevalence in these larger specimens, in which the viability of larvae was also high. Larval viability was not found to be affected by a 24-h refrigeration period. Anisakis was the most prevalent genus identified in the fish examined. The results indicate that gutting at the supermarket is not an effective method for the total removal of ascaridoid larvae and that additional safety measures are advisable.

Anisakiasis and Anisakis: An underdiagnosed emerging disease and its main etiological agents

Anisakiasis or anisakiosis is a human parasitic infection caused by the third-stage larvae (L3) of nematodes of the genus Anisakis, although the term is also used in medical literature for the much less frequent (<3% of cases) infection by L3 of other genera of anisakids, particularly Pseudoterranova. These parasites have a marine lifecycle. Humans are infected by the L3 through ingesting of fish and squid, the intermediate/paratenic hosts. The live larvae generally penetrate the wall of the stomach or intestine causing, among other symptoms, intense pain or allergic symptoms. These are emerging, cosmopolite illnesses. Diagnosis and treatment is usually by endoscopy and extraction and identification of the larvae. Allergic forms are usually diagnosed by prick-test and/or allergen-specific IgE detection and treated with a suitable anti-allergy treatment. The patient is also warned against further consumption of marine fish or squid, as these may be infected with Anisakis. The most common method of prevention is thermal treatment of the entire fish or squid prior to consumption (>60 °C, >1 min or - 20 °C, >24 h). Useful measures for the control of anisakiasis would be to establish a national register of cases, to initiate educational campaigns for the general public and consciousness-raising and training campaigns for health professionals. These would be complemented by control measures for the relevant sectors of the economy: fish operators, fish farming, fishermen, fishmongers, fish industry and catering facilities. Possible genetic predisposition for allergy to Anisakis and the possible relationship between anisakiasis and cancer would also require further investigation.

Anisakis Nematodes in Fish and Shellfish- from infection to allergies

Anisakidosis is a zoonotic parasitosis induced by members of the family Anisakidae. The anisakid genera includes Anisakis, Pseudoterranova, Hysterothylacium and Contracaecum. The final definitive hosts of these nematodes are marine mammals with a complex life cycle. These nematode parasites use different crustaceans and fish species as intermediate or paratenic hosts and humans are accidental hosts. Human anisakiasis, the infections caused by members of the genus Anisakis, occurs, when seafoods, particularly fish, contaminated with the infective stage (third stage larvae [L3]) of this parasite, are consumed. Pseudoterranovosis, on the other hand is induced by members of the genus Pseudoterranova. These two genera of anisakids have been implicated in human disease globally. There is a rise in reports of gastro-intestinal infections accompanied by allergic reactions caused by Anisakis simplex and Anisakis pegreffii. This review provides an update on current knowledge on Anisakis as a food-borne parasite with special focus on the increasingly reported diversity of fish and crustacean hosts, allergens and immunological cross-reactivity with invertebrate proteins rendering this parasite a significant public health issue.

Anisakis sensitization in different population groups and public health impact: A systematic review

Anisakis simplex spp. sensitization rates have increased worldwide, with a significant impact on health-care systems. To date, no clear-cut diagnostic criteria and laboratory algorithm have been established, so anisakiasis still represents an under-reported health problem whose clinical manifestations, when present, mimic the much more common allergic and digestive disorders. Aim of the study was to systematically review the available literature on the prevalence of sensitization against Anisakis in the general population and in specific population groups, taking into account the impact of the different available diagnostic techniques on the epidemiological data. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement, relevant papers reporting Anisakis sensitization epidemiological data were found covering a period ranging from 1996 to February 2017. Overall, 41 studies comprising 31,701 participants from eleven countries were included in the qualitative synthesis. General asymptomatic population resulted sensitized to Anisakis in 0.4 to 27.4% of cases detected by means of indirect ELISA or ImmunoCAP specific IgE detection, and between 6.6% and 19.6% of the samples by Skin prick test (SPT). Occupationally exposed workers (fishermen, fishmongers and workers of fish-processing industries) documented specific IgE between 11.7% and 50% of cases, whereas SPT positivity ranged between 8% and 46.4%. Symptomatic allergic patients to any kind of allergen were found to be positive to Anisakis specific IgE detection between 0.0% (in children with mastocytosis) to 81.3% (among adults with shellfish allergy). Results highlighted that hypersensitivity prevalence estimates varied widely according to geographical area, characteristics of the population studied, diagnostic criteria and laboratory assays. Further studies are needed to overcome the documented misdiagnosis by improving the diagnostic approach and, consequently, providing more affordable estimates in order to address public health interventions on populations at high risk of exposure to Anisakis and to tailor health services related to specific groups.

Anisakis - immunology of a foodborne parasitosis

Anisakis species are marine nematodes which can cause zoonotic infection in humans if consumed in raw, pickled or undercooked fish and seafood. Infection with Anisakis is associated with abdominal pain, nausea and diarrhoea and can lead to massive infiltration of eosinophils and formation of granulomas in the gastrointestinal tract if the larvae are not removed. Re-infection leads to systemic allergic reactions such as urticarial or anaphylaxis in some individuals, making Anisakis an important source of hidden allergens in seafood. This review summarizes the immunopathology associated with Anisakis infection. Anisakiasis and gastroallergic reactions can be prevented by consuming only fish that has been frozen to -20°C to the core for at least 24 hours before preparation. Sensitization to Anisakis proteins can also occur, primarily due to occupational exposure to infested fish, and can lead to dermatitis, rhinoconjunctivitis or asthma. In this case, exposure to fish should be avoided.

New Perspectives on the Diagnosis of Allergy to Anisakis spp

PURPOSE OF REVIEW

To compare the prevalence of sensitization in different countries based on specific IgE values and to evaluate the use of isolated native or recombinant allergens for diagnosis.

RECENT FINDINGS

Isolated allergens help in the diagnosis of truly sensitized patients avoiding false positives due to cross-reactions. Their use is therefore highly recommended, especially when used as a combination of several relevant allergens. The use of purified allergens allows an accurate diagnosis and this has led to three important findings: (1) in addition to the digestive route of sensitization, occupational and non-digestive exposure seems to be clinically relevant. (2) The parasite appears as an important agent for chronic urticaria. And (3) in endemic countries, the amount of highly sensitized subjects in the general population could be as high as 7%. Adequate information to asymptomatic patients on fish consumption habits would avoid new contacts with parasite allergens and decrease their specific IgE levels and consequently the appearance of acute or chronic episodes induced by the parasite.

Activity of Tagetes minuta Linnaeus (Asteraceae) essential oil against L3 Anisakis larvae type 1

OBJECTIVE

To evaluate in vitro effects of Tagetes minuta L. essential oil (TEO) on L3 Anisakis larvae type 1.

METHODS

In order to evaluate the potential use of Tagetes minuta essential oil against L3 Anisakis larvae three different media were tested: 1) a saline solution (SS); 2) an industrial marinating solution (MS); 3) sunflower seeds oil (SO). For each media and concentrations of TEO (0.1%, 0.5%, 1.0% and 5.0% v/v), 20 parasites were introduced into plastic Petri dishes (diameter 90 mm) and maintained at room temperature. As controls, larvae were maintained without TEO under identical experimental conditions in SS, MS and SO. A total of 900 larvae were tested. The normalized mean viability, LT100, LT50 and the percentage of inactivation at 24 h were calculated.

RESULTS

In vitro tests revealed a complete inactivation of parasites in saline solution after 2 h with 5% and 1% of TEO. In marinating solution, a complete inactivation of parasites was observed after 4 h at all concentrations used. A slower activity for all TEO concentration was reported in SO.

CONCLUSIONS

The results obtained, showing a strong activity against Anisakis larvae, confirm TEO as a larvicidal agent in the treatment of human anisakidosis and in the industrial marinating process.

Riesgos para la salud asociados al parasitismo del pescado por nematodos de los géneros Anisakis y Pseudoterranova/Health hazards related to occurrence of parasites of the genera Anisakis and Pseudoterranova in fish

Anisakiasis, also named larva migrans visceral or eosinophilic granuloma, is a widespread ictiozoonosis. Occurrence of this parasitic disease in Spain has risen dramatically in the last decade. The presence of Anisakis spp. and related species in fish presents both a potential public health threat to humans and also an important cause of economic losses for fish processing industries. Anisakiasis is transmitted through comsumption of fish and squid that harbor the third stage larvae of parasites belonging to the Anisakidae family, both raw or minimally processed. Changes in the way that fish is handled and processed after its capture and also in how fish is cooked at home and elsewhere, could explain why this parasitic disease is progressing so rapidly during the second half of this century. The importance of this parasitosis is growing as a consequence both of the high incidence of Anisakis spp. in fish and the widespread consumer ignorance of this potential threat.

Eosinophilic Enteritis Due to Anisakis: A Call for Pathologists' Attention

Anisakis simplex, a common parasite of the fish we eat, can cause eosinophilic enteriis by direct parasitization. The authors describe six cases of intestinal anisakiasis dignosed by morphologic and immunologic studies in vivo and in vitro, five being retospective cases of unclassified eosinophilic enteritis. All patients presented with symptoms of acute abdomen requiring urgent surgery. They all had segmental lesions in the jejunum and/or ileum. Histologically the authors observed eosinophilic miroabscesses; in two cases Anisakis larvae were found. None of the patients declared having eaten raw fish. The surgical pathologist plays a basic role in detecting this disase, although additional serologic investigation of anti-Anisakis IgE and a skin test should be done whenever possible.

Simultaneous Detection and Prevalence of Allergens in Anisakis Species Isolated from Marine Fishes

This study was conducted to develop a multiplex reverse transcription (RT) PCR for the detection of Anisakis allergens and to investigate the relationship between allergen profiles and anisakid larvae isolated from Scomber japonicus, Trichiurus lepturus, and Conger myriaster in Korea. The species of Anisakis was determined using Anisakis pegreffii-specific PCR and restriction fragment length polymorphism analysis. The prevalence and profiles of five Ani s allergens were examined by multiplex RTPCR. A. pegreffii and Anisakis typica accounted for 97.1 and 2.9%, respectively, of the 140 larvae examined. In A. pegreffii, allergen prevalence was 41.2% for Ani s 1, 72.1% for Ani s 2, 69.9% for Ani s 3, 86.7% for Ani s 4, and 93.4% for Ani s 5. Most A. pegreffii larvae had multiple allergen profiles, and 80.7% of A. pegreffii carried both Ani s 4 and Ani s 5, which are heat-resistant allergens. Fifty-two to 65% of A. pegreffii isolated from S. japonicus and C. myriaster carried all five Ani s allergens.

Ani s 11-Like Protein Is a Pepsin- and Heat-Resistant Major Allergen of Anisakis spp. and a Valuable Tool for Anisakis Allergy Component-Resolved Diagnosis

BACKGROUND

Anisakis simplex is a fish parasite responsible for gastrointestinal and allergic symptoms in humans. The Ani s 11-like protein has been proposed as an Anisakis allergen because its primary structure is similar to that of Ani s 11. The aims of this work were to analyse the frequency of detection of the Ani s 11-like protein and assess its diagnostic value.

METHODS

rAni s 11-like protein, rAni s 5 and rAni s 4 were expressed in Escherichia coli and rAni s 1 was produced in Pichia pastoris. Recombinant allergen detection patterns in 37 Anisakis-sensitised patients were determined. The stability to pepsin digestion and heat treatment of rAni s 11-like protein was also analysed by IgE immunoblotting.

RESULTS

Ani s 11-like protein is a major allergen detected by 78% of Anisakis-allergic patients, and 13.5% of patients detect only the rAni s 11-like allergen. This allergen is heat stable because it retains its capability of binding IgE after boiling for 30 min and it is resistant to pepsin digestion for 120 min.

CONCLUSIONS

These data indicate that the Ani s 11-like protein is a pepsin- and heat-resistant major allergen (Ani s 11.0201) of Anisakis spp. and a valuable tool for Anisakis allergy component-resolved diagnosis.

Ventricular fibrillation by anaphylaxis following consumption of blue_skinned fish

Case

Approximately 4_h after eating mackerel sushi, a 65_year_old man developed generalized itchiness and redness, after which he became unresponsive. He went into a state of ventricular fibrillation but after he was defibrillated twice, his heartbeat returned. The electrocardiogram obtained immediately after hospitalization showed some ST_segment depression, but a subsequent electrocardiogram showed improvement. Coronary CT showed no obvious stenosis or plaque in the coronary artery.

Outcome

Results of an IgE_RAST test confirmed that the level of allergen_specific IgE for mackerel measured <0.10_UA/mL, while the level for anisakis was 1.91_UA/mL.

Conclusions

As for the mechanism leading to cardiac arrest, it is thought that the histamines and leukotrienes released from cardiac mast cells caused a coronary artery spasm (Kounis syndrome). This anaphylactic shock is considered to be a result of anisakis allergy, but in general cases of anaphylaxis resulting from consumption of blue_skinned fish.

Anisakis/Ascaris IgE ratio improves specificity for the diagnosis of Anisakis simplex sensitization in travellers and immigrants

Anisakis simplex is a fish parasite responsible for human infection and is able to induce IgE-mediated reactions with several clinical manifestations. Laboratory diagnosis of Anisakis allergy is based on the detection of specific IgE using parasite whole antigen. Unfortunately, these diagnostic tools detect cross-reactivities with other nematodes and micro-organisms leading to low specificity of the diagnostic tests. The aim of this retrospective study was to assess the diagnostic value of specific IgE to Anisakis for diagnosis of A. simplex-sensitization in native Spanish residents (IMM, n=766) and subjects coming from tropical and sub-tropical geographic areas (TRO, n=233). Since Ascaris is the human parasite most closely related to Anisakis, specific IgE to Ascaris was also determined to assess Anisakis cross-reaction with other nematodes and the diagnostic value of Anisakis/Ascaris IgE ratio for Anisakis allergy was examined. IMM and TRO groups showed similar specific IgE to Anisakis levels, while TRO had higher levels of specific IgE to Ascaris than IMM group (p=0.001). ROC curve analysis determined that an Anisakis specific IgE threshold of 0.71 kU/L yielded 93% and 82% specificities in IMM and TRO groups, respectively. A cut-off value ≥4.4 for Anisakis/Ascaris IgE ratio increased specificity to 95% for samples having IgE to Ascaris ≥0.35. In conclusion, the ratio of specific IgE to Anisakis and Ascaris improved remarkably the specificity and this parameter easily obtained from the commercially available system could be useful in the diagnosis of hypersensitivity to A. simplex.

Anisakidosis in Korea; Changes Over the Last Decade

<p>Anisakidosis is caused by <italic>Anisakis simplex</italic> and other anisakids larvae parasitizing marine fish and cephalopods. A lot of case reports about anisakidosis have been published in Korea because of raw fish eating habits. Recently seafood consumption has continued to increase due to health concerns and thus, it increases the risk for infectious diseases including anisakidosis. The aim of this review is to analyze the clinical and epidemiological characteristics of anisakidosis during the last 10 years in Korea, based on the case reports published from 2000 to 2010. The incidence age was changed from 30s and 40s to 50s. The young generation was considered to consume seafood in various ways, including raw fish as well. The most noticeable change was the appearance of <italic>Anisakis</italic> allergy patients over the last decade. The patients showed abdominal pain, urticaria after eating sea food. It reaffirmed that anisakid infection induces not only gastric and intestinal anisakidosis but also cause allergic reaction. Anisakid should be considered as a possible causative food allergen provoking allergic responses after eating raw fish.</p>

Snow crab allergy and asthma among Greenlandic workers--a pilot study

Objectives

To study snow crab sensitization, occupational allergy and asthma in the snow crab industry in Greenland, as high rates have been found in Canada, but no reports have emerged from the same industry in Greenland.

Study design

Pilot survey.

Methods

Twenty workers (19 of Inuit and 1 of other origin) in a snow crab (Chionoecetes opilio) and Atlantic shrimp (Pandalus borealis) processing plant in Greenland were assessed with skin prick tests (SPTs) with common aeroallergens and specific allergens from snow crab and shrimp extracts, spirometry, blood sampling for total IgE and specific IgE determination. Eighteen workers contributed a questionnaire-based medical interview.

Results

Positive skin prick test reactions were common to snow crab (40%) and shrimp (20%). Specific IgE to snow crab were positive in 4 workers (21%). Two workers had elevated total IgE levels. Symptoms suggestive of asthma were common (45%). Work-related symptoms of skin rash, rhinitis, and/or conjunctivitis were reported by 50%, and symptoms from the lower airways by 39%. Combining history of work-related symptoms with results from specific SPTs and/or specific IgE determination suggested that 11 and 22% of workers suffered from probable and possible occupational asthma, respectively, whereas 22% had possible occupational dermatitis or rhinitis.

Conclusions

Greenlander Inuit do not appear to be protected against sensitization to snow crab or shrimp when occupationally exposed to these. This pilot study suggests that occupational allergy and asthma may be as common a problem in Greenlandic workers as in Canadian.

Anisakis simplex sensu stricto and Anisakis pegreffii: biological characteristics and pathogenetic potential in human anisakiasis

Anisakiasis is one of the most common fishborne helminthic diseases in Japan, which is contracted by ingesting the larvae of the nematode Anisakis spp. carried by marine fish. Anisakis simplex sensu stricto (s.s.) and A. pegreffii are the dominant species in fish caught offshore Japan. The present study aimed to identify the anisakid species infecting Japanese patients and determine whether there is any difference in the pathogenetic potential of A. simplex (s.s.) and A. pegreffii. In total, 41 and 301 Anisakis larvae were isolated from Japanese patients and chub mackerel (Scomber japonicus), respectively; these were subjected to molecular identification using polymerase chain reaction targeted at a ribosomal DNA internal transcribed spacer region. Chub mackerel larvae were further examined for survival in artificial gastric juice (pH 1.8) for 7 days and for invasiveness on 0.75% solid agar over a 24-h interval. All clinical isolates, including those of asymptomatic, acute, and chronic infections as well as those from the stomach, small intestine, colon, and stool, were identified as A. simplex (s.s.). Chub mackerel harbored A. simplex (s.s.) and A. pegreffii larvae, together with a few larvae of other anisakid species. A. simplex (s.s.) larvae from chub mackerel tolerated the artificial gastric juice better than A. pegreffii, with 50% mortality in 2.6 and 1.4 days, respectively. In addition, A. simplex (s.s.) penetrated the agar at significantly higher rates than A. pegreffii. These results show that A. simplex (s.s.) larvae have the potential to survive acidic gastric juice to some extent and penetrate the stomach, small intestine, or colon in infected humans.

Seroprevalence of antibodies against Anisakis simplex larvae among health-examined residents in three hospitals of southern parts of Korea

The present study was performed to estimate the seroprevalence of larval Anisakis simplex infection among the residents health-examined in 3 hospitals in southern parts of Korea. A total of 498 serum samples (1 serum per person) were collected in 3 hospitals in Busan Metropolitan city, Masan city, and Geoje city in Gyeongsangnam-do (Province) and were examined by IgE-ELISA and IgE-western blotting with larval A. simplex crude extract and excretory-secretory products (ESP). The prevalence of antibody positivity was 5.0% and 6.6% with ELISA against crude extracts and ESP, respectively. It was also revealed that infection occurred throughout all age groups and higher in females than in males. A specific protein band of 130 kDa was detected from 10 patients with western blot analysis against crude extract and ESP among those who showed positive results by ELISA. Our study showed for the first time the seroprevalence of anisakiasis in Korea. The allergen of 130 kDa can be a candidate for serologic diagnosis of anisakiasis.

Differential requirements for interleukin (IL)-4 and IL-13 in protein contact dermatitis induced by Anisakis

BACKGROUND

Exposure to antigens of the fish parasite Anisakis is associated with the development of protein contact dermatitis in seafood-processing workers. Understanding the basic mechanisms controlling allergic sensitization through the skin is critical for designing therapies that will prevent the progression of allergic disease.

OBJECTIVE

To investigate the roles of interleukin (IL)-4, IL-13 and the IL-4Ralpha in both local skin pathology and systemic sensitization following epicutaneous exposure to Anisakis proteins.

METHODS

BALB/c wild-type (WT) mice and mice deficient in IL-4, IL-13 or IL-4 and IL-13, as well as mice with cell-specific impairment of IL-4Ralpha expression, were sensitized to Anisakis antigen by repeated epicutaneous application of Anisakis extract. Following this sensitization, skin pathology was recorded and systemic responses were investigated. Intravenous challenge with Anisakis extract was performed to test for the development of biologically relevant systemic sensitization.

RESULTS

In WT mice, epicutaneous sensitization with Anisakis larval antigens induced localized inflammation, epidermal hyperplasia, production of T(H)2 cytokines, antigen-specific IgE and IgG1. Intravenous challenge of sensitized mice resulted in anaphylactic shock. Interestingly, IL-13 deficient mice failed to develop epidermal hyperplasia and inflammation, whilst anaphylaxis was reduced only in strains deficient either in IL-4 only, or deficient in IL-4 and IL-13 concurrently, as well as in mice deficient in IL-4Ralpha or with impaired IL-4Ralpha expression on CD4(+) T cells.

CONCLUSIONS

Interleukin-13 plays a central role in protein contact dermatitis associated with repeated epicutaneous exposure to Anisakis extract, whereas IL-4 drives systemic sensitization and resultant anaphylactic shock.

The clinical characteristics of Anisakis allergy in Korea

Anisakidae larvae can cause anisakiasis when ingested by humans. Although several groups have reported a gastrointestinal Anisakis allergy among people in Spain and Japan, our report is the first to summarize the clinical features of 10 Anisakis allergy cases in Korea. We enrolled 10 Korean patients (6 men and 4 women) who complained of aggravated allergic symptoms after ingesting raw fish or seafood. Sensitization to Anisakis was confirmed by detecting serum specific IgE to Anisakis simplex. The most common manifestation of anisakiasis was urticaria (100%), followed by abdominal pain (30%) and anaphylaxis (30%). All patients presenting with these symptoms also exhibited high serum specific IgE (0.45 to 100 kU/L) to A. simplex. Nine patients (90%) exhibited atopy and increased total serum IgE levels. The fish species suspected of carrying the Anisakis parasite were flatfish (40%), congers (40%), squid (30%), whelk (10%), and tuna (10%). Anisakis simplex should be considered as a possible causative food allergen in adult patients presenting with urticaria, angioedema, and anaphylaxis following the consumption of raw fish or seafood.

Seroprevalence of anti-Gymnorhynchus gigas (Trypanorhyncha, Gymnorhynchidae) antibodies in a Spanish population

The somatic products released from ingested larvae of Gymnorhynchus gigas parasitizing fish induce a Th2 response capable of causing allergic disorders. The objective of the present work was to evaluate the prevalence of anti-Gymnorhynchus gigas antibodies in a Spanish population and established a possible relationship with fish consumption habits. We studied 305 residents in Madrid, with neither clinical symptoms suggestive of gastrointestinal or allergic disorders, nor pathologies related to ingestion of fish that could cause disease. Specific antibody levels were measured by ELISA: 11.8%, 20%, 15.7%, 21%, and 7.5% of the total studied sera were IgA, Ig's, IgG, IgM, and IgE positive, respectively. Seropositivity was not more prevalent among fresh fish consumers and did not increase with frequency of fish consumption. IgE values were lower in the group that never ingested smoked fish. Anti-G. gigas antibody levels were higher in the group that reported frequent consumption of marinated fish. The use of cooking methods with the least heating efficacy (frying, or frying in batter, and microwaving) did not affect seropositivity percentages among consumers. Infection with live plerocercoids is not necessary for seropositivity, and the antibody production, in this case, is due to the absorption of antigens from the parasite following the digestion process. The human health risks of allergic reactions due to parasite antigens remain active after freezing the fish.

Anisakis simplex: from obscure infectious worm to inducer of immune hypersensitivity

Infection of humans with the nematode worm parasite Anisakis simplex was first described in the 1960s in association with the consumption of raw or undercooked fish. During the 1990s it was realized that even the ingestion of dead worms in food fish can cause severe hypersensitivity reactions, that these may be more prevalent than infection itself, and that this outcome could be associated with food preparations previously considered safe. Not only may allergic symptoms arise from infection by the parasites ("gastroallergic anisakiasis"), but true anaphylactic reactions can also occur following exposure to allergens from dead worms by food-borne, airborne, or skin contact routes. This review discusses A. simplex pathogenesis in humans, covering immune hypersensitivity reactions both in the context of a living infection and in terms of exposure to its allergens by other routes. Over the last 20 years, several studies have concentrated on A. simplex antigen characterization and innate as well as adaptive immune response to this parasite. Molecular characterization of Anisakis allergens and isolation of their encoding cDNAs is now an active field of research that should provide improved diagnostic tools in addition to tools with which to enhance our understanding of pathogenesis and controversial aspects of A. simplex allergy. We also discuss the potential relevance of parasite products such as allergens, proteinases, and proteinase inhibitors and the activation of basophils, eosinophils, and mast cells in the induction of A. simplex-related immune hypersensitivity states induced by exposure to the parasite, dead or alive.

Humoral immune responses induced by Gymnorhynchus gigas extracts in BALB/c mice

The aim of this study was to determine if the plerocercoid larvae of Gymnorhynchus gigas, a common cestode of the ray’s bream (Brama raii), possess antigenic compounds potentially capable of provoking anaphylactic episodes. A murine experimental model, using BALB/c mice, was developed to study the humoral immune response induced by G. gigas extracts. A highly specific humoral immune response was detected and cross-reactions were not observed between parasite and host antigens. The presence of IgM and IgG3 levels suggest the presence of thymus-independent antigens in the parasitic extract. The IgG antibody class showed the highest levels, with the IgG1 the predominant subclass. These IgG1 levels are in accordance with the supposed presence of a type I allergic reaction after the ingestion of G. gigas plerocercoids parasitizing fish, as well as inducing anaphylaxia in fish. These results indicate that somatic products released from ingested larvae of G. gigas could induce the development of a Th2 response capable of causing allergic disorders.

Scanning electron microscopy of Anisakis larvae following different treatments

Ingestion of fish parasitized with Anisakis larvae can produce infestation and/or allergy in consumers. Technological and food processing treatments have been applied to parasitized fish in order to kill the larvae and avoid the infestation; however, their influence on allergenicity has not been studied. Four lots of hake (Merluccius merluccius) steaks artificially parasitized with Anisakis larvae were subjected to two storage chilling (5 degrees C +/- 1 degrees C) and freezing (-20 degrees C +/- 1 degrees C) treatments and two food processing treatments of heat (final temperature 86.3 degrees C) and microwave (final temperature 66.9 degrees C) and studied by scanning electron microscopy, environmental scanning electron microscopy (ESEM) (acid [pH = 2] and water preparations), and emission of fluorescence. Anisakis larvae were resistant to acid conditions, remaining alive after treatment. Larvae in the heat- and microwave-treated lots presented coagulated and disrupted zones in the cuticle with release of fluids. The cylindrical shape changed to a dehydrated appearance mainly observed by ESEM. Fluorescence was only noticeable in the frozen larvae. Larvae without apparent changes, together with dehydrated ones, were observed by ESEM in the frozen lot; nevertheless, no disruptions in the cuticle were perceptible. Further studies are needed in order to elucidate if the changes observed in the cuticle reduce the resistance of the parasites to the action of gastric enzymes in the gastrointestinal tract and to determine the release of allergens to the flesh by the live larvae during chilled storage of the fish.

Exposure to the fish parasite Anisakis causes allergic airway hyperreactivity and dermatitis

BACKGROUND

Several case reports show allergy and anaphylactic reactions to the fish parasite Anisakis in the domestic and occupational setting. Further research is needed on the prevalence and mechanisms of disease.

OBJECTIVE

To determine the prevalence of Anisakis sensitization and related symptoms among workers in 2 fish-processing factories, and to use gene-deficient mice to determine the working mechanisms of Anisakis allergy.

METHODS

A modified version of the European Community Respiratory Health Survey was used to interview 578 South African fish-processing workers. Sensitization to Anisakis, seafood, and common aeroallergens was determined by skin prick test. Lung function was measured by spirometry and methacholine challenge. Serum eicosapentaenoic acid levels were used as an index of seafood consumption. Sensitized wild-type, IL-4, or IL-4 receptor alpha-deficient mice were challenged orally with Anisakis extract. Allergic reactions, lung pathology, antibodies, cytokines, mast cell proteases, and histamine were evaluated.

RESULTS

The prevalence of sensitization to Anisakis was higher than the prevalence of sensitization to fish (8% vs 6%). Anisakis-specific IgE reactivity was associated with bronchial hyperreactivity and dermatitis, and significantly increased with fish consumption. In mice, Anisakis infective larvae (L3) induced a striking T(H)2/type 2 response. Food-allergic-type reactions induced by oral challenge with Anisakis extract were absent in IL-4 receptor alpha knockout mice.

CONCLUSION

Anisakis sensitization in fish-processing workers is associated with allergic symptoms and correlates with high levels of fish consumption. Anisakis proteins induce allergic reactions in sensitized mice by IL-4/IL-13-mediated mechanisms.

CLINICAL IMPLICATIONS

Anisakis allergy should be considered in fish-processing workers with allergic symptoms.

The time course of biological and immunochemical allergy states induced by anisakis simplex larvae in rats

Oral infection by Anisakis simplex third stage larvae (L3) frequently gives rise to an allergic response. To comprehend the allergic and immune responses induced by L3, we investigated the kinetics of specific antibody isotype expression and the time course of biological and immunochemical allergy states using sera prepared from rats orally infected with L3 twice, with an interval of 9 weeks between infections. Biological and immunochemical allergy states were analysed by RBL-2H3 exocytosis and by indirect ELISA for IgE, respectively. The peak IgM at reinfection (RI) was comparable or similar to that at primary infection (PI) both in levels analysed by indirect ELISA and in antigen recognition analysed by Western blot. IgG1 and IgG2a levels were higher and showed accelerated kinetics after RI vs. after PI. However, the level of IgG2b was substantially lower than that of IgG2a. Peak immunochemical and biological allergy states for RI were higher and were reached faster than those for PI. The peak biological allergy state was observed at 1 week postreinfection and this occurred sooner than that for the peak immunochemical allergy state found at 2 weeks postreinfection. Our analysis of the relationship between specific IgE avidity and biological allergy state did not show any meaningful correlation. These results suggest that the allergic response induced by L3 oral infection is predominantly caused by reinfection and that this is accompanied by an elevated IgM level, which further suggests that the biological allergy state might not be related to specific IgE avidity.

Detection of Anisakis simplex-induced basophil activation by flow cytometry

BACKGROUND

Laboratory diagnosis of anisakidosis is based on specific serum IgE detection. Recently, detection of allergen-induced basophil activation by flow cytometry has been proposed as a valuable tool for allergy diagnosis.

OBJECTIVE

To evaluate if detection of Anisakis-induced basophil activation by flow cytometry is a useful tool in the diagnosis of Anisakis allergy.

METHODS

Patients with Anisakis allergy (A.s.+, n = 37), patients reporting chronic urticaria or abdominal pain unrelated to fish ingestion (A.s.-, n = 51), and healthy controls (n = 12) were studied. Specific IgE to Anisakis simplex (A. simplex) was quantified with CAP-FEIA method, and basophil activation test was performed with three different concentrations of an Anisakis crude extract. Basophil gating was performed with CD123 and HLA-DR, and cellular activation was measured with CD63.

RESULTS

A.s.+ patients showed significantly higher age and total IgE levels than did the A.s.- patients. Specific IgE to A. simplex correlated with the activated basophil percentages obtained with 15 microg/mL (r = 0.80; P < 0.001), 1.5 microg/mL (r = 0.84; P < 0.001), and 0.15 microg/mL (r = 0.82; P < 0.001) of A. simplex crude extract. Nine individuals (3 in the A.s.+ group and 6 in the A.s.- group) were nonresponders to basophil stimulation with anti-IgE. Five A.s.- patients showed positive IgE values to A. simplex while the basophil activation test was negative. According to the receiver operating characteristics curves performed between A.s.+ vs. A.s.- and A.s.+ vs. healthy controls, the cutoff for a positive basophil activation test was >or=21% (specificity = 96%, sensitivity = 100%), and 16% (sensitivity and specificity of 100%) respectively. When nonresponders were included in the A.s.+ vs. A.s.- analysis, sensitivity decreased to 95%. Multivariate logistic analysis showed that the specific basophil activation was a factor independently associated with clinical symptoms of A. simplex allergy.

CONCLUSIONS

Detection of A. simplex-induced basophil activation by flow cytometry is a useful laboratory technique for the diagnosis of anisakidosis, supplementing specific IgE determinations.

Anisakis simplex allergy: a murine model of anaphylaxis induced by parasitic proteins displays a mixed Th1/Th2 pattern

The study of the singular hypersensitivity reactions to Anisakis simplex (A.s) proteins, may help us to undestand many of the unknown immune interactions between helmiths infections and allergy. We have developed a murine model of allergy to A. simplex, that mimics human A. simplex allergy to study the specific aspects of anaphylaxis induced by parasites. Male C3H/HeJ mice were intraperitoneally sensitized to A. simplex. Mice were then intravenous or orally challenged with A. simplex. Antigen-specific immunoglobulins, polyclonal IgE, anaphylactic symptoms, plasma histamine levels and cytokine profiles were determined. Comparative IgE immunoblot analyses were also performed. Specific IgE, IgG(1) and IgG(2a) were detected in sensitized mice since week 3. Polyclonal IgE raised and peaked with different kinetics. Intravenous A. simplex challenge produced anaphylaxis in mice, accompanied by plasma histamine release. Oral A. simplex challenge in similarly sensitized mice did not caused symptoms nor histamine release. Numerous A. simplex allergens were recognized by sensitized mouse sera, some of them similar to human serum. The A. simplex stimulated splenocytes released IL-10, IFN-gamma, IL-4, IL-13 and IL-5. We describe a new animal model of anaphylaxis. It exhibits characteristics of type I hypersensitivity reactions to Anisakis simplex similar to those observed in allergic humans. Different responses to i.v. or oral A. simplex challenges emerged, which did not reflect a window tolerization period. The cytokine profile developed (mixed Th(1)/Th(2) pattern) differed from the observed in classical models of anaphylaxis or allergy to food antigens. This model may permit to investigate the peculiar allergic reactions to parasitic proteins.

Seafood allergy: lessons from clinical symptoms, immunological mechanisms and molecular biology

Food allergy consists of a wide range of disorders that result from adverse immune responses to dietary antigens. Manifestations of allergic response includes acute, potentially fatal anaphylactic reactions and a variety of chronic diseases that mainly affect the gastrointestinal tract, skin, and respiratory tract. Tools for clinical diagnosis and management, which have not changed much in the past two decades, include the clinical history, tests for specific IgE antibody to suspected foods, elimination diets, oral food challenges, and provision of medications such as epinephrine for emergency treatment. On the other hand, recent immunological and molecular biological research have enhanced our understanding of the mechanisms of these disorders and revealed the identities of many food allergens. Here, we will discuss seafood allergies with respect to the clinical manifestations, diagnosis, immunological mechanisms, and molecular biology of seafood allergens. Furthermore, potential applications and future directions in the clinical management of seafood allergies are discussed.

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.

Immunochemical and Biological Analysis of Allergenicity with Excretory-Secretory Products of Anisakis simplex Third Stage Larva

BACKGROUND

Anisakis simplex third stage larvae (L3) are parasites that frequently give rise to allergic responses. The larvae molt into fourth stage larvae (L4), and at each stage they produce L3-excretory-secretory products (L3-ESP) and L4-ESP, respectively, which are different in their main protein constituents. Although the allergenicity of L4-ESP has been investigated by several research groups, research on the allergenicity of L3-ESP has not been carried out by any researcher. In this investigation, the allergenicity and antigenicity of L3-ESP were investigated in comparison with L4-ESP, using rat sera.

METHODS

Rat sera were produced by L3 oral infection two times with a 9-week interval. Larvae ESP prepared by culture were concentrated and fractioned using lyophilizer and a centrifugal filter device, respectively. Immunochemical analysis was performed using both indirect ELISA and immunoblot. Biological allergenicity was analyzed by RBL-2H3 exocytosis.

RESULTS

With the indirect ELISA, the optical density (OD) value of the nonfractioned (NF)-L3ESP was only one third of that of the NF-L4ESP in both specific IgM and IgG. On measuring specific IgE, the OD of NF-L3ESP was less than one tenth of that of NF-L4ESP. In addition, neither antigen nor allergen was shown in NF-L3ESP, but it was shown in NF-L4ESP with immunoblot. However, the biological allergenicity of NF-L3ESP was comparable to that of NF-L4ESP. To demonstrate the presence of any allergen, L3-ESP was fractioned and found to carry twelve visualized allergen bands from 10 to 186 kDa by immunoblot.

CONCLUSIONS

These results indicate that L3-ESP may include the important allergens necessary to induce the allergy by L3 oral infection, as compared to L4-ESP.

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.