Lactase-induced occupational protein contact dermatitis and allergic rhinoconjunctivitis

Safety evaluation of the food enzyme β-galactosidase from the non-genetically modified Papiliotrema terrestris strain AE-BLC

The food enzyme β-galactosidase (β-d-galactoside galactohydrolase; EC 3.2.1.23) is produced with the non-genetically modified Papiliotrema terrestris strain AE-BLC by Amano Enzyme Inc. The food enzyme was considered free from viable cells of the production organism. It is intended to be used in the production of galacto-oligosaccharides (GOS) from lactose. Dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 0.441 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by means of a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 1800 mg TOS/kg bw per day, the highest dose tested, which, when compared with the estimated dietary exposure, resulted in a margin of exposure of at least 4082. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that a risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, but the likelihood is low. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use.

The cow's milk allergy that wasn't: allergy to supplemental oral lactase enzyme

BACKGROUND

Allergy to supplemental lactase is sparsely reported in the literature with only one prior case of anaphylaxis documented [2]. Reactions to this agent can occur following cow's milk ingestion which could lead to an erroneous diagnosis of cow's milk allergy in the absence of another explanation.

CASE PRESENTATION

Our patient, a 48-year-old male with eczema, exercise-induced asthma and rhinoconjunctivitis, presented with four episodes of systemic reactions characterized by mucosal swelling and asthma symptoms following ice-cream exposure. It was later recognized that he had been taking a lactase enzyme supplement just prior to all of his reactions. Epicutaneous testing was strongly positive to a saline slurry of the lactase supplement he had been using. The patient has been avoiding supplemental lactase since with no subsequent reactions.

DISCUSSION

Our patient was diagnosed with an allergy to supplemental lactase enzyme on the basis of convincing Immunoglobulin E (IgE) mediated symptoms and positive skin testing. He continued to eat cow's milk products, ruling out an IgE-mediated allergy to cow's milk. In the literature, there is one prior case of anaphylaxis documented. Another case of localized oropharyngeal symptoms described in the literature was thought to be a form of oral allergy syndrome as the patient had positive epicutaneous testing to Aspergillus oryzae-derived lactase as well as Aspergillus species. Occupational sensitization, rhinitis/asthma, and protein contact dermatitis have also been detailed in the literature. Although rare, this case highlights the importance of a thorough history of over-the-counter supplements when assessing a patient with features of anaphylaxis.

Safety evaluation of the food enzyme β-galactosidase from the non-genetically modified Kluyveromyces lactis strain AE-KL

The food enzyme β-galactosidase (β-d-galactoside galatohydrolase, EC 3.2.1.23) is produced with the non-genetically modified Kluyveromyces lactis strain AE-KL by Amano Enzyme Inc. As the production strain meets the requirements for a Qualified Presumption of Safety (QPS) approach to safety assessment and as no other issues of concern were identified, the Panel considered that toxicological tests were not needed for the assessment of this food enzyme. The food enzyme is intended to be used for lactose hydrolysis in milk processing (including infant formulae), production of fermented milk products and manufacture of galacto-oligosaccharides (GOS). The dietary exposure to the food enzyme-total organic solids (TOS) was estimated to be up to 7.933 mg TOS/kg body weight (bw) per day in European populations. A search for similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood for this to occur is considered to be low. Based on the QPS status of the production strain and the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Anaphylaxis to supplemental oral lactase enzyme

Background

Anaphylactic reactions involving IgE mediated hypersensitivity have been frequently reported for a number of uncommon foods. However, cases of anaphylaxis to over the counter vitamins and oral supplements have been rarely published. Lactose intolerance affects approximately 20% of Canadians and roughly 70% of the world’s population of any age. Lactose intolerance develops primarily due to the absence of the enzyme lactase and treatment involves avoidance of lactose-containing foods or ingestion of commercially available lactase enzyme preparations prior to their consumption. This case report represents the first documented evidence of anaphylaxis after exposure to supplemental lactase enzyme preparation.

Case presentation

A 38 years old Caucasian female presented with a history of self-diagnosed adult-onset lactose intolerance and a suspected allergy to lactase containing tablets. She reported an episode of bilateral orbital swelling, shortness of breath, and throat constriction after oral ingestion of a supplemental lactase enzyme tablet. Her symptoms slowly resolved with the administration of inhaled salbutamol and oral diphenhydramine. She handled lactase tablets for years to her children who were lactose intolerant, but had never ingested the tablets herself prior to the reported episode. In clinic, physical examination was benign, and skin prick testing to a slurry of the lactase tablet revealed a strongly positive reaction wheal size of 10 mm and flare of 60 mm with normal controls. The patient reported throat tightness and constriction after skin prick testing and required cetirizine treatment and observation in clinic. Subsequent skin testing was performed with individual ingredients of the lactase tablet provided by the manufacturer and Aspergillus niger, a common bacteria used in lactase preparations. Only concentrated lactase enzyme elicited a positive response. The patient was diagnosed with lactase tablet induced anaphylaxis due to synthetic lactase enzyme IgE mediated allergy, and was advised to avoid all products containing lactase enzymes as an ingredient and to carry an epinephrine auto-injector.

Conclusion

This is the first documented case report of an anaphylactic reaction to supplemental lactase enzyme. This case report reinforces the importance of thorough allergy assessment, education on avoidance of triggers, in particular with uncommon allergens.

Occupational sensitization to lactase in the dietary supplement industry

Aerogen lactase exposure carries a risk for the development of allergic asthma and rhinitis; only a few occupationally affected patients have been reported. The authors report the results of allergy testing with employees of a lactase tablets manufacturing plant. The survey involved 13 workers, including a questionnaire, spirometry, basophil activation test (BAT), and skin prick tests (SPTs) with lactase and a panel of common aeroallergens. Furthermore, lactase-specific immunoglobulin E (IgE) antibodies were analyzed. Sensitization to lactase could be proven for 9 workers by SPT and BAT; specific IgE antibodies could be detected in serum samples of all sensitized. However, IgE levels ≥0.35 kU/L were only found in 4 sera. These data confirm that occupational exposure to lactase can induce IgE-mediated respiratory sensitization resulting in allergic diseases. Protective measures should thus be obligatory when working with lactase.

New occupational and environmental causes of asthma and extrinsic allergic alveolitis

Asthma and extrinsic allergic alveolitis (EAA) remain prevalent respiratory diseases and the cause of a significant disease burden. This article reviews the recent occupational and environmental causes described for these conditions. Even over the limited time spam addressed by this article, novel agents and new data relating to already suggested causes have been described. Various types of work tasks or exposures are described that appear to cause both asthma and EAA. Isocyanates, the best example of dual potential to cause asthma and EAA are discussed, as is the new understanding of the role metal-working fluids play when causing respiratory diseases.

Industrial fungal enzymes: an occupational allergen perspective

Occupational exposure to high-molecular-weight allergens is a risk factor for the development and pathogenesis of IgE-mediated respiratory disease. In some occupational environments, workers are at an increased risk of exposure to fungal enzymes used in industrial production. Fungal enzymes have been associated with adverse health effects in the work place, in particular in baking occupations. Exposure-response relationships have been demonstrated, and atopic workers directly handling fungal enzymes are at an increased risk for IgE-mediated disease and occupational asthma. The utilization of new and emerging fungal enzymes in industrial production will present new occupational exposures. The production of antibody-based immunoassays is necessary for the assessment of occupational exposure and the development of threshold limit values. Allergen avoidance strategies including personal protective equipment, engineering controls, protein encapsulation, and reduction of airborne enzyme concentrations are required to mitigate occupational exposure to fungal enzymes.