Allergy to pumpkin and cross-reactivity to other Cucurbitaceae fruits

Hand and Foot Dermatitis Secondary to Zucchini Exposure

Contact dermatitis is an inflammatory condition mediated by allergens and irritants, including food. There have been few reports of zucchini causing contact dermatitis outside of ingestion. We report a case of allergic contact dermatitis to zucchini secondary to sensitization by a past squash exposure. The patient was treated with both systemic and topical corticosteroids.

Recurrent Anaphylaxis with Watermelon and Pumpkin Seeds in a Boy Tolerant to Their Pulps

Background: Seeds are widely consumed as a traditional snack and have rich contents beneficial to health. With an increase in consumption rates, allergic reactions occur more frequently. We focus on multiple seed consumption related to recurrent anaphylaxis in this case. Case Presentation: We evaluated an 11-year-old boy with recurrent anaphylaxis. According to his medical records, he had been hospitalized several times, diagnosed with anaphylaxis, and treated. The family noticed direct (eating) or indirect contact with pumpkin seeds. In addition, the family mentioned another anaphylactic episode after watermelon seed and poppy seed bread consumption. We conducted skin prick-to-prick tests, examined total immunoglobulin E levels, and prescribed the treatment with an adrenalin autoinjector and preventive dietary recommendations. Conclusion: Anaphylaxis, particularly recurrent ones, should be evaluated with detailed anamnesis and supported with laboratory tests. Although seeds are beneficial and highly nutritious, it is necessary to consider them a source of allergens.

Anaphylaxis after consumption of pumpkin seeds in a 2-y-old child tolerant to its pulp: A case study

OBJECTIVES

Pumpkin and its seeds are increasingly consumed by children for their potential health benefits. Each day, approximately 30% of teenagers consume nuts and seeds, including pumpkin seeds. However, there is some evidence that pumpkin seeds may exert allergenic effects and induce severe life-threatening anaphylaxis. Allergy to melon, cucumber, and zucchini, which belong to the same Cucurbitaceae family as pumpkin, are well known, opposite to pumpkin allergy. Few descriptions of allergic reactions associated with pumpkin have been published, especially in children. To date, three cases of pumpkin pulp and two seed cases have been reported among children. Our case report describes a case of pumpkin seed anaphylaxis in a child with good tolerance of pulp.

METHODS

In the present study, a 2-y-old child experienced anaphylaxis, presenting with generalized urticaria, swollen lips, and increasing dyspnea after consuming pumpkin seeds.

RESULTS

The patient's history showed that, although the child had been receiving an elimination diet because of an immunoglobulin E (IgE)-mediated food allergy to cow's milk and eggs, the basic dietary element was pumpkin pulp. The skin-prick test was positive for pumpkin seed (5 mm) but negative for pumpkin pulp (1 mm), and allergen-specific IgE was 1.34 kUA/L for seed and 0.37 kUA/L for pulp. The component-resolved diagnostics (CRD) found IgE to sesame seed, buckwheat, and walnut (storage proteins). Based on these findings, severe anaphylactic reaction to pumpkin seeds was identified.

CONCLUSIONS

Pumpkin seed anaphylaxis can develop in a child with a tolerance to pumpkin pulp. Pumpkin seed allergens have not been well characterized. Homology between amino-acid sequences in storage proteins may indicate cross reactivity between different edible seeds and nuts.

Clinical Relevance of Cross-Reactivity in Food Allergy

The diagnosis and management of food allergy is complicated by an abundance of homologous, cross-reactive proteins in edible foods and aeroallergens. This results in patients having allergic sensitization (positive tests) to many biologically related foods. However, many are sensitized to foods without exhibiting clinical reactivity. Although molecular diagnostics have improved our ability to identify clinically relevant cross-reactivity, the optimal approach to patients requires an understanding of the epidemiology of clinically relevant cross-reactivity, as well as the food-specific (degree of homology, protein stability, abundance) and patient-specific factors (immune response, augmentation factors) that determine clinical relevance. Examples of food families with high rates of cross-reactivity include mammalian milks, eggs, fish, and shellfish. Low rates are noted for grains (wheat, barley, rye), and rates of cross-reactivity are variable for most other foods. This review discusses clinically relevant cross-reactivity related to the aforementioned food groups as well as seeds, legumes (including peanut, soy, chickpea, lentil, and others), tree nuts, meats, fruits and vegetables (including the lipid transfer protein syndrome), and latex. The complicating factor of addressing co-allergy, for example, the risks of allergy to both peanut and tree nuts among atopic patients, is also discussed. Considerations for an approach to individual patient care are highlighted.

Safety evaluation of the food enzyme l-ascorbate oxidase from Cucurbita pepo L. and Cucurbita moschata Duchesne

The food enzyme l-ascorbate: oxygen oxidoreductase (EC 1.10.3.3) is extracted from fruit peels of Cucurbita pepo L. and Cucurbita moschata Duchesne by Nagase (Europa) GmbH. This enzyme is intended to be used in baking and cereal-based processes. Based on maximum use levels recommended for the respective food processes and individual data from the EFSA Comprehensive European Food Consumption Database, dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 5.950 mg TOS/kg body weight per day in European populations. This exposure is in the same order of magnitude for infants and toddlers; but for children, adolescents, adults and the elderly it is one order of magnitude higher than the exposure to the fraction of the fruit peels comparable to the food enzyme-TOS. The Panel, while recognising the order of magnitude of difference in the exposure estimates, considers that any realistic exposure derived from the use of the food enzyme would be considerably lower and likely to be within the range of exposure through a typical diet. The Panel agreed that the requirements for exclusion of toxicological data were met. Amino acid sequence similarity to known allergens was searched and no match was found. The Panel considered that the risk of allergic sensitisation and elicitation reactions upon dietary exposure to this food enzyme cannot be excluded, but are not expected to exceed the likelihood of the allergic reactions following consumption of pumpkin or zucchini per se, which is low. Based on the data provided and the origin of the food enzyme from edible parts of C. pepo L. and C. moschata Duchesne, the Panel considers that the food enzyme l-ascorbate oxidase does not raise safety concerns under the intended conditions of use.

Hypersensitivities to sesame and other common edible seeds

Several seeds have been increasingly incorporated in various food items, with consequent risk of hypersensitivity reactions that are often severe. Identification of the specific seed as the culprit is often not explored or is difficult to verify. In this article, we reviewed the English literature from January 1930 to March 2016 using PubMed and Google Scholar searching for publications relevant to hypersensitivity to common edible seeds, namely sesame, sunflower seed, poppy seed, pumpkin seed, flaxseed, and mustard seed. Considering the worldwide consumption of those seeds, the number of published articles on the subject was relatively small and was mainly as case reports rather than large series. Allergy to sesame was more reported than to other seeds, with an estimated prevalence of 0.1-0.2%. In this review, we summarize the information relevant to each of the six seeds and their oils regarding the manifestations, routes of exposure, identified major allergens, and cross-reactivity with other seeds or other foods. We also addressed the important role of a thorough history taking in suspecting seed allergy, the limited reliability of routine diagnostic procedures, and the importance of verification by appropriate challenge tests. At present, management is basically dietary avoidance and the use of symptomatic medications that may include epinephrine auto-injectors. We did not encounter any well-designed studies on immunotherapy for seed allergy, but it is hoped that such a gap be filled by the development of safe effective protocols in the near future.

Effect of incorporation of pumpkin (Cucurbita moshchata) powder and guar gum on the rheological properties of wheat flour

The present study was carried out to study the effect of incorporation of fibre rich pumpkin powder and guar gum on the farinographic characteristics of wheat flour. The flour and pumpkin powder were assessed for proximate composition, total dietary fibre, minerals and β-carotene. Pumpkin powder contained appreciable amount of fibre, minerals and β-carotene. The effects of incorporation of different levels of pumpkin powder and guar gum along with pumpkin powder on farinographic characteristics were studied. Dough development time, dough stability, time to break down and farinograph quality number increased whereas mixing tolerance index decreased with incorporation of pumpkin powder (> 5 %) and guar gum (1.0 and 1.5 %) along with pumpkin powder in the flour. Resistance to extension as well as extensibility of dough prepared increased significantly by adding pumpkin powder (5-15 %) whereas increase in resistance to extension only was noticed with inclusion of guar gum (0.5-1.5 %) to flour containing 5 % pumpkin powder. Results indicated that pumpkin can be processed to powder that can be utilized with guar gum for value addition.

Identification of Cucumisin (Cuc m 1), a subtilisin-like endopeptidase, as the major allergen of melon fruit

BACKGROUND

Allergenic components in melon extracts have not been described in spite of the fact that melon (Cucumis melo) is a frequent allergy-eliciting fruit. The aim of this study was to evaluate allergenic components in melon extract and to report the identification of cucumisin as a major melon allergen.

MATERIALS AND METHODS

Sera from 35 patients allergic to melon were selected on the basis of clinical symptoms, skin prick tests and oral challenge test. Allergenic components were detected by sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting. Molecular characterization of IgE-binding bands was performed by N-terminal amino acid sequencing.

RESULTS

More than 10 IgE-binding bands, between 10 and 80 kDa, were identified in melon extract. Out of them, four IgE-binding bands were major allergens: 14 kDa, 36 kDa, 54 kDa and 67 kDa. These major allergens, except 14 kDa band, showed the same N-terminal sequence: T-T-R-S-W-D-F-L. Research conducted with protein databases identified this N-terminal sequence as cucumisin, an alkaline serine protease, which shares structural homology with microbial subtilisin. The molecular mass of the identified bands corresponds with different molecular forms of cucumisin produced during the processing or degradation of the enzyme: 67 kDa native cucumisin, 54 kDa mature cucumisin and 36 kDa NH2-terminal cucumisin fragment.

CONCLUSION

Cucumisin (Cuc m 1) and several N-terminal cucumisin fragments are the major allergens of melon. The ubiquitous distribution of this protein family (cucumisin-like proteases) in many plant species and its high structural similarity suggest its potential role as a new panallergen in plant foods.

Clinical features of cross-reactivity of food allergy caused by fruits

Fruits are increasingly recognized as a cause of food allergy. The wide cross-reactivity among these foods has been extensively studied. In this review we will focus on studies addressing the clinical relevance of cross-reactivity among fruits, the diagnostic management of patients complaining of reactions to multiple fruits, and adequate dietary recommendations.

Clinical implications of cross-reactive food allergens

As a consequence of the general increase in allergic sensitization, the prevalence of hypersensitivity reactions to multiple foods that share homologous proteins has become a significant clinical problem. A variety of these allergens conserved among plants (eg, profilin and lipid transfer proteins) and animals (eg, tropomyosin and caseins) have been characterized. Although studies with molecular biologic techniques have elucidated the nature of these ubiquitous allergens, clinical studies have lagged behind. The physician is called on to determine the risk of reaction to related foods among legumes, tree nuts, fish, shellfish, cereal grains, mammalian and avian food products, and a variety of other plant-derived foods that may share proteins with pollens, latex, and each other. Clinical evaluations require a careful history, laboratory evaluation, and in some cases oral food challenges. The pitfalls in the evaluation of food allergy-unreliable histories and limitations in laboratory assessment primarily caused by false-positive skin prick test responses/RAST results are magnified when dealing with cross-reactive proteins. This review focuses on the clinical data regarding cross-reacting food allergens with the goal of providing a background for improved risk assessment and a framework on which to approach these difficult clinical questions.

Upper airway edema resulting from use of Ecballium elaterium

OBJECTIVES

To present a rare occurrence in ear, nose and throat practice of upper airway allergic edema from use of juice extracted from the fruit of Ecballium elaterium.

INTRODUCTION

Ecballium elaterium is a plant indigenous to the Mediterranean region that bears the common name squirting cucumber. Many people in this region for the treatment of sinusitis use the juice of its fruit. However, allergy-prone patients after using it may sometimes present with edema at various sites of the upper respiratory tract. Otolaryngologists are frequently asked to diagnose and treat such an emergency situation.

STUDY DESIGN

Retrospective review of the records of 42 patients with this condition during the last 4 years.

METHODS

Patient records were retrospectively reviewed for age, sex, presenting symptoms, physical examination, and medical treatment. Seasonal distribution and data from the history of the patients were also considered. Skin prick and prick-to-prick testing to various allergens was performed in 12 patients.

RESULTS

Most of the patients presented with localized swelling of the uvula and the nasal mucosa, whereas in the remainder of the patients various sites of swelling of the upper respiratory tract were observed. Skin tests elicited positive reactions to pollen weeds and to various fruits of the Cucurbitaceae family. Treatment of the patients with corticosteroids and antihistamines resulted in an uneventful recovery, and we did not need to resort to therapeutic modalities, such as intubation or tracheotomy.

CONCLUSIONS

We think a further study of the pharmaceutical properties of the plant's fruit juice is needed, especially regarding its curative properties of rhinitis and sinusitis. However, adverse reactions in some patients with a positive history of allergy should always be considered.