Synergism between prior Anisakis simplex infections and intake of NSAIDs, on the risk of upper digestive bleeding: a case-control study

Zoonotic Marine Nematode Infection of Fish Products in Landlocked Country, Slovakia

Fish products in Slovakia have been heavily infected with Anisakis spp. larvae, which causes human anisakiasis. We found larvae in all tested samples of frozen Atlantic herring. Anisakid allergen t-Ani s7 testing revealed 2 positive cases in humans, signaling need for health authorities to closely monitor zoonotic marine parasites, even in inland areas.

Anisakis Sensitization in the Croatian fish processing workers: Behavioral instead of occupational risk factors?

We undertook the first study systematically evaluating the risk of Anisakis-sensitization in Croatian fish-processing workers and potential genetic susceptibility to anisakiasis. Anti-Anisakis IgE seroprevalence and risk factors for 600 employees of Croatian fish processing facilities and 466 blood donor controls, were assessed by indirect ELISA targeted with: recombinant Ani s 1 and Ani s 7 allergens, an Anisakis crude extract, the commercial ImmunoCAP kit, and questionnaires. Genetic susceptibility to anisakiasis was evaluated by genotypisation of human leukocytes alleles (HLA). Anti-Anisakis seropositive and a fraction of negative subjects were also assessed by ELISA and Western Blot (WB) for IgG seroprevalence to Trichinella spp. Overall, the observed anti-Anisakis seroprevalence inferred by indirect ELISA was significantly higher in fish processing workers (1.8%, 95% CI 0.9–3.3%) compared to the controls (0%, 0–0.8%). Seven out of 11 Ani s 1 and Ani s 7-positives and none of selected 65 negative sera, tested positive on whole-Anisakis extract (ImmunoCAP), whereas Anisakis crude extract ELISA detected 3.9% (2.4–6.0%) seropositives in fish processing workers, three (14%) of which showed IgE reactivity to milk proteins. The highest risk associated with Anisakis-sensitization among workers was fishing in the free time, rather than any of attributes related to the occupational exposure. Although no association was observed between anti-Anisakis seropositivity and wearing gloves or protective goggles, the majority of workers (92%) wore protective gloves, minimizing the risk for Anisakis sensitization via skin contact. Six HLA alleles within DRB1 gene were significantly associated with seropositivity under dominant, allelic or recessive models. All sera confirmed negative for anti-Trichinella spp. IgG. The study exhaustively covered almost all marine fish processing workers in Croatia, reflecting real-time Anisakis sensitization status within the industry, already under the influence of wide array of allergens.

Anisakiasis is a human disease caused by ingestion of live Anisakis spp. larvae by raw seafood. Fish processing and aquaculture workers (approximately 60 million people world-wide) are at occupational risk of becoming sensitized to Anisakis. This is the first study systematically evaluating the risk of Anisakis-sensitization in Croatian fish-processing workers and potential genetic susceptibility to anisakiasis in the analysed population. Observed seroprevalence was significantly higher in fish processing workers (1.8%) compared to the controls (0%). Surprisingly, the highest risk associated with Anisakis-sensitization among workers was fishing in their free time, rather than any of attributes related to the occupational exposure. While no association was observed between anti-Anisakis seropositivity and wearing gloves or protective goggles, the majority of workers (92%) wore protective gloves, minimizing the risk for Anisakis sensitization via skin contact. Additionally, seroprevalence to another important food-borne helminth, Trichinella spp. assessed in all Anisakis-positive subjects showed to be negative. Almost all marine fish processing workers in Croatia were part of this research, reflecting real-time Anisakis-sensitization status within the industry. This sets a baseline for the future tracking of sensitization in the sector already under the influence of wide array of allergens.

Exposure to Anisakis extracts can induce inflammation on in vitro cultured human colonic cells

Anisakis spp. is a parasitic nematode whose infective third-stage larvae may be found within the flesh of fish species commonly consumed by humans. Thorough cooking or freezing should render the fish safe for consumption; furthermore, marinating solutions containing biocidal agents might have a significant action against Anisakis larvae. Some studies suggest a relationship between some parasitic infections and development of inflammatory bowel disorders, and Anisakis infection might be a risk factor for stomach or colon cancer. The aim of our study was to investigate if crude extracts (CEs) obtained from Anisakis larvae marinated in a solution with added allyl isothiocyanate (ACE-AITC) and frozen, or from frozen only Anisakis larvae (ACE), can induce an inflammatory effect on in vitro differentiated colonic Caco-2 cells exposed or not to LPS. Caco-2 exposure to the two CEs induced a marked COX-2 expression and potentiated LPS-induced COX-2 overexpression, confirming that substances present in Anisakis larvae can induce an inflammatory response in the intestinal epithelium, possibly also exacerbating the effects of other inflammatory stimuli. ACE induced a marked decrease in caspase-3 activation, while AITC-ACE increased its activation. However, LPS-induced caspase-3 activation appeared lower in cells treated with ACE and with the lower concentration of AITC-ACE. Thus, it is evident that Anisakis CEs may affect various cell pathways crucial not only in the inflammatory process but also in cell growth and death. Thus, CEs obtained from nonviable Anisakis larvae retain or are otherwise provided with noxious properties able to induce a strong inflammation response in intestinal epithelial cells. Furthermore, their influence may persist also following pretreatment with the biocidal agent AITC, indicating that the harmful substances contained in crude extracts from Anisakis larvae are resistant to the thermal or biocidal agent treatments.

A case report of Anisakis pegreffii (Nematoda, Anisakidae) identified from archival paraffin sections of a Croatian patient

BACKGROUND

This is the first report of anisakiasis in a Croatian patient, evidenced from an archival paraffin-embedded and hematoxylin-eosin stained tissue section. Anisakiasis has been only suspected in the country based on previously detected anti-Anisakis IgE seroprevalence in the healthy coastal population, as well as an acute case where pathohistological and serological findings suggested the diseases, but the migrating larva has not been retrieved.

CASE PRESENTATION

Seventy years-old female, operated in 1998 for pulmonary carcinoma, was admitted to the General hospital Šibenik, Croatia in 2003, because of gastric pain and nausea that lasted for couple of days. She was showing good general condition, full mobility and lucidity, subfebrile status. Abdominal palpation inferred acute pain in paraumbilical and ileocecal region. Exploratory right pararectal laparotomy revealed a hardened, 5 cm-long structure, located intraluminally in the sigmoid colon, not perforating colon serosa. The process has been dissected and sent for patohistological diagnosis. Results showed a 2 mm-long whitish nematode spiralised in muscular layer of colon mucosa surrounded by granulomatous inflammation.

CONCLUSION

After genomic DNA isolation of the nematode from the histological section, and amplification at the mitochondrial cytochrome oxidase 2 locus, etiological agent has been identified as Anisakis pegreffii. Used methodology suggests that screening of archival suspicious sections is feasible in order to study epidemiology of this zoonotic disease poorly recognised in Croatia.

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.

Hookworm infestation is not an uncommon cause of obscure occult and overt gastrointestinal bleeding in an endemic area: A study using capsule endoscopy

Obscure gastrointestinal bleeding (OGIB), particularly occult, has been reported to be caused by hookworm infestation rarely from tropical countries, particularly India. Hence, we undertook a retrospective study evaluating frequency, clinical spectrum, and outcome of patients with OGIB associated with worm infestation. Data of consecutive patients with OGIB undergoing capsule endoscopy in a multilevel university hospital in northern India were retrospectively analyzed. Twenty-one out of 163 (13 %) patients with OGIB had hookworm infestation detected on capsule endoscopy. Of 21 patients (median age 65 years [range 19-82], 17 [81 %] male), 16 had overt and 5 had occult OGIB. Another lesion that could explain OGIB was present in 8/21 patients, 3/5 with OGIB occult, and 5/16 overt (p = ns). All the patients received treatment with albendazole and appropriate measures for the associated lesion, if any. Patients with hookworm infestation with another lesion experienced recurrent bleeding more often than those with worm infestation only. Hookworm infestation is an important cause of occult as well as overt OGIB and may be present even in association with another lesion. Those with additional lesion had recurrent bleeding more often than those with worm infestation alone.

Molecular genotyping of anisakis larvae in Middle Eastern Japan and endoscopic evidence for preferential penetration of normal over atrophic mucosa

BACKGROUND

Anisakiasis is a parasitic disease caused primarily by Anisakis spp. larvae in Asia and in Western countries. The aim of this study was to investigate the genotype of Anisakis larvae endoscopically removed from Middle Eastern Japanese patients and to determine whether mucosal atrophy affects the risk of penetration in gastric anisakiasis.

METHODS

In this study, 57 larvae collected from 44 patients with anisakiasis (42 gastric and 2 colonic anisakiasis) were analyzed retrospectively. Genotyping was confirmed by restriction fragment length polymorphism (RFLP) analysis of ITS regions and by sequencing the mitochondrial small subunit (SSU) region. In the cases of gastric anisakiasis, correlation analyses were conducted between the frequency of larval penetration in normal/atrophic area and the manifestation of clinical symptoms.

RESULTS

Nearly all larvae were A. simplex seusu stricto (s.s.) (99%), and one larva displayed a hybrid genotype. The A. simplex larvae penetrated normal mucosa more frequently than atrophic area (p = 0.005). Finally, patients with normal mucosa infection were more likely to exhibit clinical symptoms than those with atrophic mucosa infection (odds ratio, 6.96; 95% confidence interval, 1.52-31.8).

CONCLUSIONS

In Japan, A. simplex s.s. is the main etiological agent of human anisakiasis and tends to penetrate normal gastric mucosa. Careful endoscopic examination of normal gastric mucosa, particularly in the greater curvature of the stomach will improve the detection of Anisakis larvae.

Anti-Anisakis IgE seroprevalence in the healthy Croatian coastal population and associated risk factors

BACKGROUND

The main objective of the study was to determine the degree of sensitization to Anisakis spp. antigens in healthy coastal population of Dalmatia given the high thermally unprocessed fish intake rate present in this area, suggested as a significant risk factor for anisakiasis. We performed a monocenter, cross-sectional pilot study stratified by geographic area of residence, conducted at the County secondary healthcare provider Medicine-biochemical Laboratory in Split (Croatia), from November 2010 till December 2011, on 500 unpaid volunteer subjects undergoing routine blood analysis and belonging to the south coast of the Adriatic Sea.

METHODOLOGY/PRINCIPAL FINDINGS

We studied the IgE seroprevalence to Anisakis spp. Ani s l and Ani s 7 allergens by indirect ELISA in healthy subjects, which were selected at random in the region of Dalmatia (Southern Croatia), among islands, coastal urban and inland rural populations. In order to detect possible cross-reactivity to other human helminthes, serum samples were tested also for the presence of IgG antibodies to Ascaris lumbricoides and Toxocara canis. The overall and coastal Anisakis seroprevalences for the sampled population were 2% and 2.5%, respectively. The logistic univariate regression analysis confirmed that regarding anti-Anisakis IgE seroprevalence, raw fish intake, daily fish intake, homemade origin of fish dish and occupational contact (professional, artisanal or hobby contact with fishery or fish industry) were risk factors associated to Anisakis spp. sensitization, but neither of the variables was exclusive for a particular seropositive population. Also, a significant difference was observed between seropositive and seronegative subjects that had stated allergy or symptoms associated with allergy (atopic dermatitis, asthma or rhinitis) in their previous history.

CONCLUSIONS/SIGNIFICANCE

Being the first in Croatia, our study underlines the necessity of incorporating Anisakis spp. allergens in routine hypersensitivity testing of coastal population.

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.