Ignacio Moneo

Anisakis simplex, a relevant etiologic factor in acute urticaria

Del Pozo MD, Audícana M, Diez JM, Muñoz D, Ansotegui IJ, Fernández E, García M, Etxenagusia M, Moneo I, Fernández de Corres L. Anisakis simplex, a relevant etiologic factor in acute urticaria.

Laboratory determinations in Anisakis simplex allergy

BACKGROUND Anaphylactic reactions caused by the fish nematode, Anisakis simplex, after ingestion of parasitized fish, have been described. OBJECTIVE This study was undertaken to confirm, by histamine release tests, that A. simplex is able to trigger IgE-mediated reactions and to describe the serologic profiles in this sensitization. METHODS Twelve patients who had anaphylactic symptoms after ingestion of cooked fish and positive prick test results and determinations of IgE to A. simplex were studied by indirect IgG ELISA and IgG and IgE immunoblotting. Sera from subjects parasitized with other nematodes, patients with fish allergy, and healthy donors were included as controls. A histamine release test was performed in a representative case. RESULTS IgE immunoblotting was a specific test to detect A. simplex allergy. IgE-reacting bands were found in serum samples from 11 of our patients. Specific IgG antibodies were found by ELISA and immunoblotting, but this response was less specific. Histamine release was positive with A. simplex extract and negative with fish. CONCLUSION A specific and intense immune response to an A. simplex extract was found in our patients. A. simplex is able to elicit anaphylactic reactions, and A. simplex allergy should be suspected in patients with allergic symptoms after ingestion of fish. A positive prick test response to A. simplex and a negative response to fish is a good indication for a diagnosis of A. simplex allergy.

The use of IgE immunoblotting as a diagnostic tool in Anisakis simplex allergy.

BACKGROUND The fish parasite Anisakis simplex is the etiologic agent of anisakiasis and induces IgE-mediated reactions. Skin prick tests (SPTs) and the measurement of specific IgE to A. simplex were, in our experience, not valid tools with which to discriminate between allergic and nonallergic patients because many control subjects also had positive results. OBJECTIVE The study was carried out to assess the usefulness of IgE immunoblotting in the diagnosis of allergy to A. simplex. METHODS We have studied 61 patients with acute symptoms of urticaria, angioedema, or anaphylaxis and positive specific IgE to A. simplex. According to the anamnesis, time interval between ingestion of fish and clinical onset of symptoms, and exclusion of other causes of allergy, three different groups of patients were established: group A (allergic), group NA (non-allergic), and group D (doubtful). Fifty-one healthy donors were included as control subjects (group C). IgE immunoblotting with A. simplex whole-body extract was performed in all patients and control subjects. RESULTS Four patterns of immunoblotting were observed: type 1, with a group of several bands of medium molecular weight and others of low molecular weight; type 2, two or more bands of medium molecular weight; type 3, only one band of medium molecular weight; type 4, without any band. There was a significant predominance of blotting type 1 in group A and type 4 in group C. CONCLUSION These data suggest that IgE immunoblotting is the most useful approach to A. simplex allergy diagnosis.

Occupational immunologic contact urticaria from pine processionary caterpillar (Thaumetopoea pityocampa): experience in 30 cases.

Cutaneous lesions caused by the pine processionary caterpillar Thaumetopoea pityocampa (TP) are frequent in pinewood areas. In the present study, 30 patients diagnosed with occupational immunologic urticaria from this caterpillar were included. Immediate hypersensitivity was demonstrated by performing prick and IgE‐immunoblotting tests. Workers were grouped according to their common tasks. Occupations at risk of exposure to TP were pine‐cone collectors/woodcutters (14), farmers/stockbreeders (8), other forestry personnel (4), construction workers (2), residential gardeners ( 1 ) and entomologists ( 1 ). Besides contact urticaria, angioedema (60%), papular lesions of several days of evolution (30%) and anaphylactic reactions (40%) were also detected. The most frequently detected molecular weight bands by immunoblot were 15 (70%), 17 (57%) and 13 kDa (50%). The appearance of isolated bands corresponds with the least serious cases. Only 8 subjects had bands higher than 33 kDa, which was present in the 3 most severe cases of anaphylactic reactions. By presenting these cases, we wish to offer the largest series reported so far of occupational immunologic contact urticaria caused by TP. We include the first cases described in certain occupations, some of them not directly related to forestry work. Pine‐cone or resin collectors, woodcutters, farmers and stockbreeders were the most frequently and severely affected workers.

Pine processionary caterpillar as a new cause of immunologic contact urticaria

Nowadays, caterpillars are included among the agents that elicit contact urticaria by a non‐immunologic mechanism. Our objective was to find the rôle that an IgE‐mediated mechanism could have among patients with suspected contact urticaria from pine processionary caterpillars. 16 patients with suspected contact urticaria from this caterpillar were studied by prick testing and specific IgE detection by immunoblotting. 87% of the patients had a positive prick test and immunoblotting for caterpillar extract. In these allergic patients, the symptoms associated with urticaria were: angioedema (79%), conjunctivitis (36%) and severe anaphylaxis (14%). The most frequent localizations of the wheals were the neck (100%) and forearms (93%). Angioedema was more frequent on the eyelids (79%). The IgE‐immunoblot detected in the caterpillar extract several reactive bands, with apparent MWs from to 45 to 4kDa. A total of 5 major allergens were identified, but a band around 14kDa proved to be the dominant allergen. Sensitization to Thaumetopoea pityocampa was found to be the most important mechanism of airborne contact urticaria from this caterpillar. Low‐MW proteins are the main IgE binding components of crude caterpillar extract.

Anaphylaxis to a pine caterpillar

• A 41-year-old male pine-forest worker was admitted with a history of a sudden onset of itching rash that started in the neck and then extended to the whole body, with tongue edema, shortness of breath, weakness, blurred sight, and nausea. He said he had disturbed caterpillar nests while knocking pine cones down with a long pole. ——^^^^^———^-^— The patient was nonatopic although he had complained of rash and conjunctivitis for several years, but these symptoms appeared only in association with his work. On physical examination, his blood pressure was 8(V5(J, and the patient had tongue edema and a generalized rash, although it mainly involved the neck. Chest radiography, electrocardiogram, and physical examination were normal. He received 1 mg of subcutaneous epinephrine, as well as tnethylprednisolone and dexchlorpheniramine, both intravenously. A case of severe, IgE-

Occupational asthma caused by cellulase

Inhalation of enzyme dusts can cause occupational asthma, and the list of enzymes able to induce asthma is increasing. We report two patients with asthma induced by occupational exposure to cellulase powder derived from Aspergillus niger. A type I hypersensitivity to this enzyme was demonstrated by means of skin test reactivity, positive passive transfer test, positive reverse enzyme immunoassay for specific IgE, and immediate bronchial provocation test response to cellulase dust. Skin tests with an A. niger extract were positive. Cross-reactivity between cellulase dust and an entire A. niger extract was also demonstrated.

Cloning and expression of Ani s 9, a new Anisakis simplex allergen.

The larvae of the nematode Anisakis simplex parasitize seafood. When people eat raw or undercooked parasitized fish, they can suffer anisakiasis, an important immune human response to parasitic infection of the gastrointestinal tract. Even more, allergic manifestations like angioedema, urticaria or anaphylaxis can occur in sensitized patients. The aim of this work was to clone Ani s 9-cDNA and overproduce this recombinant allergen in Escherichia coli. The finding of this allergen was an unexpected result of a PCR using degenerate primers designed to amplify Ani s 5. The complete cDNA for Ani s 9 was obtained by RACE-PCR, cloned and sequenced. Expression of recombinant allergen was performed in E. coli. Immunodetection and immunoblot inhibition assays tests were carried out with sera from Anisakis allergic patients. The recombinant Ani s 9 (rAni s 9) is a protein of 147 amino acids. By immunoblot inhibition assay, it was located as a 14 kDa band present in a crude extract of the parasite. This new allergen is heat stable and is present in excretory/secretory products. Ani s 9 belongs to the SXP/RAL-2 family and shares amino acid sequence identity of 60% with As-14, an Ascaris suum allergen. Five of thirty-six Anisakis allergic patients (13.8%) were positive to rAni s 9 and natural Ani s 9 by immunodetection. In conclusion, Ani s 9 is a new allergen in Anisakis allergy and it has been cloned and successfully expressed in E. coli.

Sensitization to serum albumins in children allergic to cow's milk and epithelia

Patients with persistent milk allergy and specific immunoglobulin E (IgE) to bovine serum albumin (BSA) have a greater risk of rhinoconjunctivitis and asthma because of animal dander. To prove the cross‐reactivity between serum albumin (SA) of different mammals in milk, meat, and epithelia and determine if heat treatment of meats decrease the allergenicity of albumins. The study was performed using SDS‐PAGE and IgE‐immunoblotting using sera from eight patients sensitized to milk, BSA, and animal danders. Sera from non‐allergic and only animal dander allergic subjects served as a control. With one exception, all patients’ sera recognized SA in different meats (beef, lamb, deer, and pork), epithelia (dog, cat, and cow), and cows milk. Some patients even were only sensitized to SA in meat and epithelia. Danders’ allergic only recognized other proteins in epithelia but not SA. No patients reacted to SA from heated meat extracts. Serum albumin is an important allergen involved in milk, meat, and epithelia allergy. The first contact with SA was through cows milk and patients developed sensitization to epithelia SA even without direct contact with animals. Patients with both BSA and cows milk allergy must avoid raw meats and furry pets.

Occupational asthma caused by α-amylase inhalation: Clinical and immunologic findings and bronchial response patterns

Inhalation of dust from different enzymes can be the cause of occupational asthma in exposed workers. alpha-Amylase, derived from Aspergillus oryzae, is one of these enzymes, although there are few studies in the medical literature that refer to its allergologic properties and to clinical studies in sensitized patients. The results obtained in a study performed in 83 pharmaceutical-industry workers exposed to powdered alpha-amylase are described in this article. The existence of sensitization to this enzyme was demonstrated in 26 of the workers by positive skin tests. Specific IgE values were significantly higher in workers with positive skin tests than in workers with negative skin tests (p less than 0.001). The bronchial provocation test with alpha-amylase was positive in six of the 14 patients challenged, and only immediate bronchial responses were observed; the same type of response was obtained by nasal provocation. One of the workers had a positive response to oral provocation with this enzyme, presenting abdominal, skin, and respiratory symptoms a few minutes after ingestion. Consequently, we consider that the bronchial asthma presented by the workers was due to an immediate-type, IgE-dependent, immunologic mechanism.