PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (1111302)

Clipboard (0)
None

Related Articles

1.  Referrals to a regional allergy clinic - an eleven year audit 
BMC Public Health  2010;10:790.
Background
Allergy is a serious and apparently increasing public health problem yet relatively little is known about the types of allergy seen in routine tertiary practice, including their spatial distribution, co-occurrence or referral patterns. This study reviewed referrals over an eleven year period to a regional allergy clinic that had a well defined geographical boundary. For those patients confirmed as having an allergy we explored: (i) differences over time and by demographics, (ii) types of allergy, (iii) co-occurrence, and (iv) spatial distributions.
Methods
Data were extracted from consultant letters to GPs, from September 1998 to September 2009, for patients confirmed as having an allergy. Other data included referral statistics and population data by postcode. Simple descriptive analysis was used to describe types of allergy. We calculated 11 year standardised morbidity ratios for postcode districts and checked for spatial clustering. We present maps showing 11 year rates by postcode, and 'difference' maps which try to separate referral effect from possible environmental effect.
Results
Of 5778 referrals, 961 patients were diagnosed with an allergy. These were referred by a total of 672 different GPs. There were marked differences in referral patterns between GP practices and also individual GPs. The mean age of patients was 35 and there were considerably more females (65%) than males. Airborne allergies were the most frequent (623), and there were very high rates of co-occurrence of pollen, house dust mite, and animal hair allergies. Less than half (410) patients had a food allergy, with nuts, fruit, and seafood being the most common allergens. Fifteen percent (142) had both a food and a non-food allergy. Certain food allergies were more likely to co-occur, for example, patients allergic to dairy products were more likely to be allergic to egg.
There were age differences by types of allergy; people referred with food allergies were on average 5 years younger than those with other allergies, and those allergic to nuts were much younger (26 Vs 38) than those with other food allergies.
There was clear evidence for spatial clustering with marked clustering around the referral hospital. However, the geographical distribution varied between allergies; airborne (particularly pollen allergies) clustered in North Dartmoor and Exmoor, food allergies (particularly nut allergies) in the South Hams, and on small numbers, some indication of seafood allergy in the far south west of Cornwall and in the Padstow area.
Conclusions
This study shows marked geographical differences in allergy referrals which are likely to reflect a combination of environmental factors and GP referral patterns. The data suggest that GPs may benefit from education and ongoing decision support and be supported by public education on the nature of allergy. It suggests further research into what happens to patients with allergy where there has been low use of tertiary services and further research into cross-reactivity and co-occurrence, and spatial distribution of allergy.
doi:10.1186/1471-2458-10-790
PMCID: PMC3022859  PMID: 21190546
2.  Occupational seafood allergy: a review 
BACKGROUND—Recent years have seen increased levels of production and consumption of seafood, leading to more frequent reporting of allergic reactions in occupational and domestic settings. This review focuses on occupational allergy in the fishing and seafood processing industry.
REVIEW—Workers involved in either manual or automated processing of crabs, prawns, mussels, fish, and fishmeal production are commonly exposed to various constituents of seafood. Aerosolisation of seafood and cooking fluid during processing are potential occupational situations that could result in sensitisation through inhalation. There is great variability of aerosol exposure within and among various jobs with reported allergen concentrations ranging from 0.001 to 5.061(µg/m3). Occupational dermal exposure occurs as a result of unprotected handling of seafood and its byproducts. Occupational allergies have been reported in workers exposed to arthropods (crustaceans), molluscs, pisces (bony fish) and other agents derived from seafood. The prevalence of occupational asthma ranges from 7% to 36%, and for occupational protein contact dermatitis, from 3% to 11%. These health outcomes are mainly due to high molecular weight proteins in seafood causing an IgE mediated response. Cross reactivity between various species within a major seafood grouping also occurs. Limited evidence from dose-response relations indicate that development of symptoms is related to duration or intensity of exposure. The evidence for atopy as a risk factor for occupational sensitisation and asthma is supportive, whereas evidence for cigarette smoking is limited. Disruption of the intact skin barrier seems to be an important added risk factor for occupational protein contact dermatitis.
CONCLUSION—The range of allergic disease associated with occupational exposure to crab is well characterised, whereas for other seafood agents the evidence is somewhat limited. There is a need for further epidemiological studies to better characterise this risk. More detailed characterisation of specific protein antigens in aerosols and associated establishment of dose-response relations for acute and chronic exposure to seafood; the respective roles of skin contact and inhalational exposure in allergic sensitisation and cross reactivity; and the contribution of host associated factors in the development of occupational seafood allergies are important areas for future research.


Keywords: occupational seafood allergy; occupational asthma; protein contact dermatitis
doi:10.1136/oem.58.9.553
PMCID: PMC1740192  PMID: 11511741
3.  Active or Passive Exposure to Tobacco Smoking and Allergic Rhinitis, Allergic Dermatitis, and Food Allergy in Adults and Children: A Systematic Review and Meta-Analysis 
PLoS Medicine  2014;11(3):e1001611.
In a systematic review and meta-analysis, Bahi Takkouche and colleagues examine the associations between exposure to tobacco smoke and allergic disorders in children and adults.
Please see later in the article for the Editors' Summary
Background
Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases, especially among children, and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. The objective of this study was to examine the evidence for an association between active smoking (AS) or passive exposure to secondhand smoke and allergic conditions.
Methods and Findings
We retrieved studies published in any language up to June 30th, 2013 by systematically searching Medline, Embase, the five regional bibliographic databases of the World Health Organization, and ISI-Proceedings databases, by manually examining the references of the original articles and reviews retrieved, and by establishing personal contact with clinical researchers. We included cohort, case-control, and cross-sectional studies reporting odds ratio (OR) or relative risk (RR) estimates and confidence intervals of smoking and allergic conditions, first among the general population and then among children.
We retrieved 97 studies on allergic rhinitis, 91 on allergic dermatitis, and eight on food allergy published in 139 different articles. When all studies were analyzed together (showing random effects model results and pooled ORs expressed as RR), allergic rhinitis was not associated with active smoking (pooled RR, 1.02 [95% CI 0.92–1.15]), but was associated with passive smoking (pooled RR 1.10 [95% CI 1.06–1.15]). Allergic dermatitis was associated with both active (pooled RR, 1.21 [95% CI 1.14–1.29]) and passive smoking (pooled RR, 1.07 [95% CI 1.03–1.12]). In children and adolescent, allergic rhinitis was associated with active (pooled RR, 1.40 (95% CI 1.24–1.59) and passive smoking (pooled RR, 1.09 [95% CI 1.04–1.14]). Allergic dermatitis was associated with active (pooled RR, 1.36 [95% CI 1.17–1.46]) and passive smoking (pooled RR, 1.06 [95% CI 1.01–1.11]). Food allergy was associated with SHS (1.43 [1.12–1.83]) when cohort studies only were examined, but not when all studies were combined.
The findings are limited by the potential for confounding and bias given that most of the individual studies used a cross-sectional design. Furthermore, the studies showed a high degree of heterogeneity and the exposure and outcome measures were assessed by self-report, which may increase the potential for misclassification.
Conclusions
We observed very modest associations between smoking and some allergic diseases among adults. Among children and adolescents, both active and passive exposure to SHS were associated with a modest increased risk for allergic diseases, and passive smoking was associated with an increased risk for food allergy. Additional studies with detailed measurement of exposure and better case definition are needed to further explore the role of smoking in allergic diseases.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
The immune system protects the human body from viruses, bacteria, and other pathogens. Whenever a pathogen enters the body, immune system cells called T lymphocytes recognize specific molecules on its surface and release chemical messengers that recruit and activate other types of immune cells, which then attack the pathogen. Sometimes, however, the immune system responds to harmless materials (for example, pollen; scientists call these materials allergens) and triggers an allergic disease such as allergic rhinitis (inflammation of the inside of the nose; hay fever is a type of allergic rhinitis), allergic dermatitis (also known as eczema, a disease characterized by dry, itchy patches on the skin), and food allergy. Recent studies suggest that all these allergic (atopic) diseases are part of a continuous state called the “atopic march” in which individuals develop allergic diseases in a specific sequence that starts with allergic dermatitis during infancy, and progresses to food allergy, allergic rhinitis, and finally asthma (inflammation of the airways).
Why Was This Study Done?
Allergic diseases are extremely common, particularly in children. Allergic rhinitis alone affects 10%–30% of the world's population and up to 40% of children in some countries. Moreover, allergic diseases are becoming increasingly common. Allergic diseases affect the quality of life of patients and are financially costly to both patients and health systems. It is important, therefore, to identify the factors that cause or potentiate their development. One potential risk factor for allergic diseases is active or passive exposure to tobacco smoke. In some countries up to 80% of children are exposed to second-hand smoke so, from a public health point of view, it would be useful to know whether exposure to tobacco smoke is associated with the development of allergic diseases. Here, the researchers undertake a systematic review (a study that uses predefined criteria to identify all the research on a given topic) and a meta-analysis (a statistical approach for combining the results of several studies) to investigate this issue.
What Did the Researchers Do and Find?
The researchers identified 196 observational studies (investigations that observe outcomes in populations without trying to affect these outcomes in any way) that examined the association between smoke exposure and allergic rhinitis, allergic dermatitis, or food allergy. When all studies were analyzed together, allergic rhinitis was not associated with active smoking but was slightly associated with exposure to second-hand smoke. Specifically, compared to people not exposed to second-hand smoke, the pooled relative risk (RR) of allergic rhinitis among people exposed to second-hand smoke was 1.10 (an RR of greater than 1 indicates an increased risk of disease development in an exposed population compared to an unexposed population). Allergic dermatitis was associated with both active smoking (RR = 1.21) and exposure to second-hand smoke (RR = 1.07). In the populations of children and adolescents included in the studies, allergic rhinitis was associated with both active smoking and exposure to second-hand smoke (RRs of 1.40 and 1.09, respectively), as was allergic dermatitis (RRs of 1.36 and 1.06, respectively). Finally food allergy was associated with exposure to second-hand smoke (RR = 1.43) when cohort studies (a specific type of observational study) only were examined but not when all the studies were combined.
What Do These Findings Mean?
These findings provide limited evidence for a weak association between smoke exposure and allergic disease in adults but suggest that both active and passive smoking are associated with a modestly increased risk of allergic diseases in children and adolescents. The accuracy of these findings may be affected by the use of questionnaires to assess smoke exposure and allergic disease development in most of the studies in the meta-analysis and by the possibility that individuals exposed to smoke may have shared other characteristics that were actually responsible for their increased risk of allergic diseases. To shed more light on the role of smoking in allergic diseases, additional studies are needed that accurately measure exposure and outcomes. However, the present findings suggest that, in countries where many people smoke, 14% and 13% of allergic rhinitis and allergic dermatitis, respectively, among children may be attributable to active smoking. Thus, the elimination of active smoking among children and adolescents could prevent one in seven cases of allergic rhinitis and one in eight cases of allergic dermatitis in such countries.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001611.
The UK National Health Service Choices website provides information about allergic rhinitis, hay fever (including personal stories), allergic dermatitis (including personal stories), and food allergy (including personal stories)
The US National Institute of Allergy and Infectious Disease provides information about allergic diseases
The UK not-for-profit organization Allergy UK provides information about all aspects of allergic diseases and a description of the atopic march
MedlinePlus encyclopedia has pages on allergic rhinitis and allergic dermatitis (in English and Spanish)
MedlinePlus provides links to further resources about allergies, eczema, and food allergy (in English and Spanish)
doi:10.1371/journal.pmed.1001611
PMCID: PMC3949681  PMID: 24618794
4.  Prevalence and characteristics of reported penicillin allergy in an urban outpatient adult population 
Allergy and Asthma Proceedings  2014;35(6):489-494.
Penicillin allergy remains the most common drug allergy, with a reported prevalence of 10% in the United States. Epidemiology of penicillin allergy in outpatient populations is relatively scarce. This study sought to determine the prevalence and characteristics of reported penicillin allergy in an urban outpatient population and to identify trends in clinical evaluation and management from a tertiary center serving a large inner-city population. A retrospective review of electronic medical records was performed of adult patients seen in the Internal Medicine Associates Clinic of Mount Sinai Hospital between January 31, 2012, and July 31, 2012. Medical records were selected based on the documentation of penicillin in patient's allergy section. Of the 11,761 patients seen in the clinic, 1348 patients (11.5%) reported a history of penicillin allergy. The most common allergic reactions were rash (37%), unknown/undocumented (20.2%), hives (18.9%), swelling/angioedema (11.8%), and anaphylaxis (6.8%). There was an increased prevalence of penicillin allergy in female patients compared with male patients (odds ratio [OR] = 1.82; 95% CI = 1.60, 2.08; p < 0.0001), and there were significantly fewer Asians with penicillin allergy compared with Caucasians (OR = 0.51; 95% CI = 0.32, 0.83; p = 0.007). However, only 78 (6%) of the patients reporting penicillin allergy had a referral to an allergy specialist. Overall, improved referral to an allergist will help to identify patients who have penicillin allergy requiring avoidance.
doi:10.2500/aap.2014.35.3791
PMCID: PMC4210656  PMID: 25584917
Adverse drug reactions; anaphylaxis; drug allergy; electronic medical record; epidemiology; outpatient; penicillin
5.  Seafood consumption among pregnant and non-pregnant women of childbearing age in the United States, NHANES 1999–2006 
Food & Nutrition Research  2014;58:10.3402/fnr.v58.23287.
Objectives
Long-chain polyunsaturated fatty acids found in seafood are essential for optimal neurodevelopment of the fetus. However, concerns about mercury contamination of seafood and its potential harm to the developing fetus have created uncertainty about seafood consumption for pregnant women. We compared fish and shellfish consumption patterns, as well as their predictors, among pregnant and non-pregnant women of childbearing age in the US.
Methods
Data from 1,260 pregnant and 5,848 non-pregnant women aged 16–49 years from the 1999 to 2006 National Health and Nutrition Examination Survey (NHANES) were analyzed. Frequency and type of seafood consumed and adjusted associations of multiple characteristics with seafood consumption were estimated for pregnant and non-pregnant women, separately. Time trends were also examined.
Results
There were no significant differences in the prevalence of fish or shellfish consumption, separately or combined, between pregnant and non-pregnant women using either the 30-day questionnaire or the Day 1, 24-h recall. Seafood consumption was associated with higher age, income, and education among pregnant and non-pregnant women, and among fish consumers these groups were more likely to consume ≥3 servings in the past 30 days. Tuna and shrimp were the most frequently reported fish and shellfish, respectively, among both pregnant and non-pregnant women. We observed no significant time trends.
Conclusion
There were no differences in seafood consumption between pregnant and non-pregnant women, and the factors related to seafood consumption were similar for both groups. Our data suggest that many women consume less than the recommended two servings of seafood a week.
doi:10.3402/fnr.v58.23287
PMCID: PMC4056189  PMID: 24959115
pregnant; fish; seafood; NHANES; mercury
6.  Food allergies in developing and emerging economies: need for comprehensive data on prevalence rates 
Although much is known today about the prevalence of food allergy in the developed world, there are serious knowledge gaps about the prevalence rates of food allergy in developing countries. Food allergy affects up to 6% of children and 4% of adults. Symptoms include urticaria, gastrointestinal distress, failure to thrive, anaphylaxis and even death. There are over 170 foods known to provoke allergic reactions. Of these, the most common foods responsible for inducing 90% of reported allergic reactions are peanuts, milk, eggs, wheat, nuts (e.g., hazelnuts, walnuts, almonds, cashews, pecans, etc.), soybeans, fish, crustaceans and shellfish. Current assumptions are that prevalence rates are lower in developing countries and emerging economies such as China, Brazil and India which raises questions about potential health impacts should the assumptions not be supported by evidence. As the health and social burden of food allergy can be significant, national and international efforts focusing on food security, food safety, food quality and dietary diversity need to pay special attention to the role of food allergy in order to avoid marginalization of sub-populations in the community. More importantly, as the major food sources used in international food aid programs are frequently priority allergens (e.g., peanut, milk, eggs, soybean, fish, wheat), and due to the similarities between food allergy and some malnutrition symptoms, it will be increasingly important to understand and assess the interplay between food allergy and nutrition in order to protect and identify appropriate sources of foods for sensitized sub-populations especially in economically disadvantaged countries and communities.
doi:10.1186/2045-7022-2-25
PMCID: PMC3551706  PMID: 23256652
Food allergy; Food hypersensitivity; Nutrition; Developing countries
7.  Shellfish allergy and relation to iodinated contrast media: United Kingdom survey 
World Journal of Cardiology  2014;6(3):107-111.
AIM: To assess current practice of United Kingdom cardiologists with respect to patients with reported shellfish/iodine allergy, and in particular the use of iodinated contrast for elective coronary angiography. Moreover we have reviewed the current evidence-base and guidelines available in this area.
METHODS: A questionnaire survey was send to 500 senior United Kingdom cardiologists (almost 50% cardiologists registered with British Cardiovascular Society) using email and first 100 responses used to analyze practise. We involved cardiologists performing coronary angiograms routinely both at secondary and tertiary centres. Three specific questions relating to allergy were asked: (1) History of shellfish/iodine allergy in pre-angiography assessment; (2) Treatments offered for shellfish/iodine allergy individuals; and (3) Any specific treatment protocol for shellfish/iodine allergy cases. We aimed to establish routine practice in United Kingdom for patients undergoing elective coronary angiography. We also performed comprehensive PubMed search for the available evidence of relationship between shellfish/iodine allergy and contrast media.
RESULTS: A total of 100 responses were received, representing 20% of all United Kingdom cardiologists. Ninety-three replies were received from consultant cardiologists, 4 from non-consultant grades and 3 from cardiology specialist nurses. Amongst the respondents, 66% routinely asked about a previous history of shellfish/iodine allergy. Fifty-six percent would pre-treat these patients with steroids and anti-histamines. The other 44% do nothing, or do nonspecific testing based on their personal experience as following: (1) Skin test with 1 mL of subcutaneous contrast before intravenous contrast; (2) Test dose 2 mL contrast before coronary injection; (3) Close observation for shellfish allergy patients; and (4) Minimal evidence that the steroid and anti-histamine regime is effective but it makes us feel better.
CONCLUSION: There is no evidence that allergy to shellfish alters the risk of reaction to intravenous contrast more than any other allergy and asking about such allergies in pre-angiogram assessment will not provide any additional information except propagating the myth.
doi:10.4330/wjc.v6.i3.107
PMCID: PMC3964187  PMID: 24669292
Shellfish allergy; Contrast allergy; Iodinated contrast allergy; Low osmolarity contrast media; High osmolarity contrast media; Pre-angiography assessment
8.  IgE mediated food allergy in Korean children: focused on plant food allergy 
Asia Pacific Allergy  2013;3(1):15-22.
Food allergy (FA) is a worldwide problem, with increasing prevalence in many countries, and it poses a clearly increasing health problem in Korea. In Korea, as a part of International Study of Asthma and Allergy in Childhood (ISAAC), a series of nation-wide population studies for prevalence of allergic disease in children were carried out, with the Korean version of ISAAC in 1995, 2000, and 2010. From the survey, the twelve-month prevalence of FA showed no significant differences from 1995 to 2000 in both age groups (6-12 years-old, 6.5% in 1995 and 5.7% in 2000; 12-15 year-olds, 7.4% in 1995 and 8.6% in 2000). The mean lifetime prevalence of FA which had ever been diagnosed by medical doctor was 4.7% in 6-12 year-olds and 5.1% in 12-15 year-olds respectively in 2000. In Korean children, the major causes of FA are almost same as in other countries, although the order prevalence may vary, a prime example of which being that peanut and tree nut allergies are not prevalent, as in western countries. Both pediatric emergency department (ED) visits and deaths relating to food induced anaphylaxis have also increased in western countries. From a study which based on data from the Korean Health Insurance Review and Assessment Service (KHIRA) from 2001 to 2007, the incidence of anaphylaxis under the age of 19 was 0.7-1 per 100,000 person-year, and foods (24.9%) were the most commonly identified cause of childhood anaphylaxis. In another epidemiologic study, involving 78889 patients aged 0-18 years who visited the EDs of 9 hospitals during June 2008 to Mar 2009, the incidence of food related anaphylaxis was 4.56 per 10,000 pediatric ED visits. From these studies, common causes of food related anaphylaxis were seafood, buckwheat, cow's milk, fruits, peanut and tree nuts. Although systematic epidemiologic studies have not reported on the matter, recently, plant foods related allergy has increased in Korean children. Among 804 children with moderate to severe atopic dermatitis, we reveals that the peanut sensitization rate in Korea reaches 18%, and that, when sensitized to peanut, patients showed a significant tendency to have co-sensitization with house dust mites, egg white, wheat, and soybean. The higher specific IgE to peanut was related to the likelihood of the patient developing severe systemic reactions. In another study, based on the data analysis of 69 patients under 4 years of age who had suspected peanut and tree nut allergy, 22 (31.9%) were sensitized to walnut (>0.35 kU/L, 0.45-27.4 kU/L) and 6 (8.7%) experienced anaphylaxis due to a small amount of walnut exposure. Furthermore, in this review, clinical and immunological studies on plant food allergies, such as buckwheat allergy, rice allergy, barley allergy, and kiwi fruit allergy, in Korean children are discussed.
doi:10.5415/apallergy.2013.3.1.15
PMCID: PMC3563016  PMID: 23403730
Food allergy; Korean children; Anaphylaxis; Plant food allergy
9.  Season of Birth is Associated with Food Allergy in Children 
Background
The prevalence of food allergy is rising and etiologic factors remain uncertain. Evidence implicates a role of vitamin D in the development of atopic diseases. Based on seasonal patterns of UVB exposure (and consequent vitamin D status), we hypothesized that food allergy patients are more often born in fall or winter.
Objective
Investigate whether season of birth is associated with food allergy.
Methods
We performed a multicenter chart review of all patients presenting to three Boston emergency departments (EDs) for food-related acute allergic reactions between 1/1/01 and 12/31/06. Months of birth among food allergy patients were compared to those of patients visiting the ED for reasons other than food allergy.
Results
We studied 1,002 food allergy patients. Among younger children with food allergy (age <5 years) – but not among older children or adults – 41% were born in spring/summer compared to 59% in fall/winter (P=0.002). This approximately 40/60 ratio differed from birth season of children treated in the ED for non-food allergy reasons (P=0.002). Children <5 years old born in fall/winter had a 53% higher odds of food allergy compared to controls. This finding was independent of the suspected triggering food and allergic comorbidities.
Conclusions
Food allergy is more common in Boston children who were born in the fall and winter seasons. We propose that these findings are mediated by seasonal differences in UVB exposure. These results add support to the hypothesis that seasonal fluctuations in sunlight and perhaps vitamin D may be involved in the pathogenesis of food allergy.
doi:10.1016/j.anai.2010.01.019
PMCID: PMC2941399  PMID: 20408340
Food allergy; season of birth; epidemiology; UVB; vitamin D
10.  Maternal fish and shellfish consumption and wheeze, eczema and food allergy at age two: a prospective cohort study in Brittany, France 
Environmental Health  2013;12:102.
Background
Environmental exposures, including dietary contaminants, may influence the developing immune system. This study assesses the association between maternal pre-parturition consumption of seafood and wheeze, eczema, and food allergy in preschool children. Fish and shellfish were studied separately as they differ according to their levels of omega-3 polyunsaturated fatty acids (which have anti-allergic properties) and their levels of contaminants.
Methods
The PELAGIE cohort included 3421 women recruited at the beginning of pregnancy. Maternal fish and shellfish intake was measured at inclusion by a food frequency questionnaire. Wheeze, eczema, and food allergy were evaluated by a questionnaire completed by the mother when the child was 2 years old (n = 1500). Examination of the associations between seafood intake and outcomes took major confounders into account. Complementary sensitivity analyses with multiple imputation enabled us to handle missing data, due mostly to attrition.
Results
Moderate maternal pre-parturition fish intake (1 to 4 times a month) was, at borderline significance, associated with a lower risk of wheeze (adjusted OR = 0.69 (0.45-1.05)) before age 2, compared with low intake (< once/month). This result was not, however, consistent: after multiple imputation, the adjusted OR was 0.86 (0.63-1.17). Shellfish intake at least once a month was associated with a higher risk of food allergy before age 2 (adjusted OR = 1.62 (1.11-2.37)) compared to low or no intake (< once/month). Multiple imputation confirmed this association (adjusted OR = 1.52 (1.05-2.21)).
Conclusions
This study suggests that maternal pre-parturition shellfish consumption may increase the risk of food allergy. Further large-scale epidemiologic studies are needed to corroborate these results, identify the contaminants or components of shellfish responsible for the effects observed, determine the persistence of the associations seen at age 2, and investigate potential associations with health effects observable at later ages, such as allergic asthma.
doi:10.1186/1476-069X-12-102
PMCID: PMC3893486  PMID: 24295221
Fish intake; Shellfish intake; Pregnancy; Wheeze; Allergy; Children
11.  Identification and validation of shrimp-tropomyosin specific CD4 T cell epitopes 
Human immunology  2013;74(12):10.1016/j.humimm.2013.08.276.
Background
Shellfish allergy is an immune-mediated adverse reaction to allergenic shellfish and is responsible for significant morbidity and mortality. CD4 T cell responses play an important role in the pathophysiological mechanisms of sensitization and in production of IgE.
Objective
We sought to identify and validate CD4 T cell shrimp tropomyosin-derived epitopes and characterize CD4 T cell responses in subjects with a clinical history of shellfish allergy.
Method
Using an in vitro MHC-peptide binding assay, we screened 91 overlapping peptides and identified 28 epitopes with moderate and strong binding capacities; 3 additional peptides were included based on MHC binding prediction score. These peptides were then examined in proliferation and cytokine release assays with T cells from allergic subjects.
Result
17 epitopes restricted to DRB*01:01, DRB1*03:01, DRB1*04:01, DRB1*09:01, DQB1*02:01, DQB1*03:02 and DQB1*05:01 alleles were identified and validated by both the MHC binding and the functional assays. Two peptides showed specificities to more than one MHC class II allele. We demonstrated that these peptides exert functional responses in an epitope specific manner, eliciting predominantly IL-6 and IL-13.
Conclusion
The identified epitopes are specific to common MHC class II alleles in the general population. Our study provides important data for the design of peptide-based immunotherapy of shrimp-allergic patients.
doi:10.1016/j.humimm.2013.08.276
PMCID: PMC3870591  PMID: 23993987
12.  Contamination by Vibrio parahaemolyticus and Its Virulent Strains in Seafood Marketed in Thailand, Vietnam, Malaysia, and Indonesia  
Tropical Medicine and Health  2013;41(3):95-102.
Infections by virulent strains of Vibrio parahaemolyticus are frequently reported in Southeast Asia. This is due to the frequent seafood contamination by virulent strains. In this study conducted from 2008 to 2011, seafood like fish, shrimp, squid, crab, and molluscan shellfish were purchased from provinces in Thailand and three Southeast Asian countries and examined for the prevalence of three genetic markers of V. parahaemolyticus (species-specific gene: toxR gene, virulence genes: tdh and trh genes). An enrichment culture of seafood was examined for these markers using PCR methods. Molluscan shellfish showed a high frequency of contamination in Thailand. The shellfish harvested from the Gulf of Thailand were significantly more contaminated with virulence genes than those from the Andaman Sea. The seafood purchased from three Southeast Asian countries was positive for the three markers of V. parahaemolytcus at differing frequencies. The virulence markers (tdh and trh markers) were frequently detected in molluscan shellfish from Vietnam (17.9 and 8.0%, respectively), Malaysia (11.1 and 16.7%), and Indonesia (9.1 and 13.6%). These data suggest that the molluscan shellfish sold in Southeast Asian markets are highly contaminated with virulent strains of V. parahaemolyticus.
doi:10.2149/tmh.2011-06
PMCID: PMC3800702  PMID: 24155650
Vibrio parahaemolyticus; Southeast Asia; seafood; molluscan shellfish
13.  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.
doi:10.3904/kjim.2009.24.2.160
PMCID: PMC2698627  PMID: 19543498
Anisakis simplex; Fish; Food allergy
14.  Specific IgE to fish extracts does not predict allergy to specific species within an adult fish allergic population 
Background
Fish is an important cause of food allergy. Studies on fish allergy are scarce and in most cases limited to serological evaluation. Our objective was to study patterns of self-reported allergy and tolerance to different commonly consumed fish species and its correlation to IgE sensitization to the same species.
Methods
Thirty-eight adult fish allergic patients completed a questionnaire regarding atopy, age of onset and symptoms to 13 commonly consumed fish species in the Netherlands (pangasius, cod, herring, eel, hake, pollock, mackerel, tilapia, salmon, sardine, tuna, plaice and swordfish). Specific IgE to these fish extracts were analyzed by ImmunoCAP.
Results
Median age of onset of fish allergy was 8.5 years. Severe reactions were reported by the majority of patients (n = 20 (53%) respiratory and of these 20 patients, 6 also had cardiovascular symptoms). After diagnosis, 66% of the patients had eliminated all fish from their diet. Allergy to all species ever tried was reported by 59%. In relation to species ever tried, cod (84%) and herring (79%) were the most frequently reported culprit species while hake (57%) and swordfish (55%) were the least frequent. A positive sIgE (value ≥ 0.35 kUA/L) to the culprit species ranged between 50% (swordfish) and 100% (hake). In tolerant patients, a negative sIgE (value < 0.35 kUA/L) ranged from 0% (hake, pollock and swordfish) to 75% (sardine). For cod, the agreement between sIgE test results and reported allergy or tolerance was 82% and 25%, respectively. Sensitization to cod parvalbumin (Gad c 1) was present in 77% of all patients.
Conclusion
Serological cross-reactivity between fish species is frequent, but in a significant proportion of patients, clinical relevance appears to be limited to only certain species. A well-taken history or food challenge is required for discrimination between allergy to the different fish species.
doi:10.1186/2045-7022-4-27
PMCID: PMC4164331  PMID: 25225608
Fish allergy; Fish species; Food allergy; Sensitization; Specific IgE
15.  Chitins and Chitosans as Immunoadjuvants and Non-Allergenic Drug Carriers 
Marine Drugs  2010;8(2):292-312.
Due to the fact that some individuals are allergic to crustaceans, the presumed relationship between allergy and the presence of chitin in crustaceans has been investigated. In vivo, chitin is part of complex structures with other organic and inorganic compounds: in arthropods chitin is covalently linked to proteins and tanned by quinones, in fungi it is covalently linked to glucans, while in bacteria chitin is diversely combined according to Gram(+/−) classification. On the other hand, isolated, purified chitin is a plain polysaccharide that, at the nano level, presents itself as a highly associated structure, recently refined in terms of regularity, nature of bonds, crystallinity degree and unusual colloidal behavior. Chitins and modified chitins exert a number of beneficial actions, i.e., (i) they stimulate macrophages by interacting with receptors on the macrophage surface that mediate the internalization of chitin particles to be degraded by lysozyme and N-acetyl-β-glucosaminidase (such as Nod-like, Toll-like, lectin, Dectin-1, leukotriene 134 and mannose receptors); (ii) the macrophages produce cytokines and other compounds that confer non-specific host resistance against bacterial and viral infections, and anti-tumor activity; (iii) chitin is a strong Th1 adjuvant that up-regulates Th1 immunity induced by heat-killed Mycobacterium bovis, while down- regulating Th2 immunity induced by mycobacterial protein; (iv) direct intranasal application of chitin microparticles into the lung was also able to significantly down-regulate allergic response to Dermatophagoids pteronyssinus and Aspergillus fumigatus in a murine model of allergy; (v) chitin microparticles had a beneficial effect in preventing and treating histopathologic changes in the airways of asthmatic mice; (vi) authors support the fact that chitin depresses the development of adaptive type 2 allergic responses. Since the expression of chitinases, chitrotriosidase and chitinase-like proteins is greatly amplified during many infections and diseases, the common feature of chitinase-like proteins and chitinase activity in all organisms appears to be the biochemical defense of the host. Unfortunately, conceptual and methodological errors are present in certain recent articles dealing with chitin and allergy, i.e., (1) omitted consideration of mammalian chitinase and/or chitotriosidase secretion, accompanied by inactive chitinase-like proteins, as an ancestral defensive means against invasion, capable to prevent the insurgence of allergy; (2) omitted consideration of the fact that the mammalian organism recognizes more promptly the secreted water soluble chitinase produced by a pathogen, rather than the insoluble and well protected chitin within the pathogen itself; (3) superficial and incomplete reports and investigations on chitin as an allergen, without mentioning the potent allergen from crustacean flesh, tropomyosine; (4) limited perception of the importance of the chemical/biochemical characteristics of the isolated chitin or chitosan for the replication of experiments and optimization of results; and (5) lack of interdisciplinarity. There is quite a large body of knowledge today on the use of chitosans as biomaterials, and more specifically as drug carriers for a variety of applications: the delivery routes being the same as those adopted for the immunological studies. Said articles, that devote attention to the safety and biocompatibility aspects, never reported intolerance or allergy in individuals and animals, even when the quantities of chitosan used in single experiments were quite large. Therefore, it is concluded that crab, shrimp, prawn and lobster chitins, as well as chitosans of all grades, once purified, should not be considered as “crustacean derivatives”, because the isolation procedures have removed proteins, fats and other contaminants to such an extent as to allow them to be classified as chemicals regardless of their origin.
doi:10.3390/md8020292
PMCID: PMC2852840  PMID: 20390107
chitin; chitosan; chitinase; chitinase-like proteins; immunology
16.  OCCUPATIONAL ALLERGY AND ASTHMA AMONG SALT WATER FISH PROCESSING WORKERS 
Background
Fish processing is a common economic activity in Southern Africa. The aim of this study was to determine the prevalence and host determinants of allergic symptoms, allergic sensitization, bronchial hyper-responsiveness and asthma among workers processing saltwater fish.
Methods
A cross-sectional study was conducted on 594 currently employed workers in two processing plants involved in pilchard canning and fishmeal processing. A modified European Community Respiratory Health Survey (ECRHS) questionnaire was used. Skin prick tests (SPT) used extracts of common airborne allergens, fresh fish (pilchard, anchovy, maasbanker, mackerel, red eye) and fishmeal. Spirometry and methacholine challenge tests (tidal breathing method) used ATS guidelines.
Results
Work-related ocular-nasal symptoms (26%) were more common than asthma symptoms (16%). The prevalence of atopy was 36%, while 7% were sensitized to fish species and 26% had NSBH (PC20 ≤ 8 mg/ml or ≥12% increase in FEV1 post bronchodilator). The prevalence of probable occupational asthma was 1.8% and fish allergic rhino-conjunctivitis 2.6%. Women were more likely to report work-related asthma symptoms (OR=1.94) and have NSBH (OR=3.09), while men were more likely to be sensitized to fish (OR=2.06) and have airway obstruction (OR=4.17). Atopy (OR=3.16) and current smoking (OR=2.37), but not habitual seafood consumption were associated with sensitization to fish.
Conclusions
Based on comparison with previous published studies, the prevalence of occupational asthma to salt water fish is lower than due to shellfish. The gendered distribution of work and exposures in fish processing operations together with atopy and cigarette smoking are important determinants of occupational allergy and asthma.
doi:10.1002/ajim.20635
PMCID: PMC2834300  PMID: 18726880
fish processing; occupational allergy; work-related asthma; atopy; smoking; gender
17.  Intake of Seafood in the US Varies by Age, Income, and Education Level but Not by Race-Ethnicity 
Nutrients  2014;6(12):6060-6075.
Current US federal dietary guidance recommends regular consumption of seafood (fish + shellfish) to promote health; however, little is known about how well Americans meet the guideline, particularly population subgroups that may be at risk for inadequate intake. The purposes of this study were to describe the prevalence of seafood consumption and, among consumers, the amounts of seafood eaten by sex, age group, income and education level, and race-ethnicity. Data from 15,407 adults aged 19+ participating in the 2005–2010 National Health and Nutrition Examination Surveys were analyzed using methods to account for sporadic intake of seafood. Over 80% of Americans reported consuming any seafood over the past 30 days, 74% reported consuming fish, and 54% reported eating shellfish. The percentages varied by socio-demographic group. Younger age and lower income and education levels were associated with lower odds of being a seafood consumer (p < 0.0001). Among those who reported eating seafood, the average amount eaten of any seafood was 158.2 ± 5.6 g/week. Among seafood consumers, women and individuals of lower age and education levels consumed less seafood. Approximately 80%–90% of seafood consumers did not meet seafood recommendations when needs were estimated by energy requirements. A great deal of work remains to move Americans toward seafood consumption at current recommended levels.
doi:10.3390/nu6126060
PMCID: PMC4277015  PMID: 25533013
seafood intake; fish; shellfish
18.  Hair Mercury Concentrations and Fish Consumption Patterns in Florida Residents 
Mercury exposure through the consumption of fish and shellfish represents a significant public health concern in the United States. Recent research has demonstrated higher seafood consumption and subsequent increased risk of methylmercury exposure among subpopulations living in coastal areas. The identification of high concentrations of total mercury in blood and skin among resident Atlantic bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon (IRL), a coastal estuary in Florida, alerted us to a potential public health hazard in the contiguous human population. Therefore, we analyzed hair mercury concentrations of residents living along the IRL and ascertained their sources and patterns of seafood consumption. The total mean mercury concentration for 135 residents was 1.53 ± 1.89 µg/g. The concentration of hair mercury among males (2.02 ± 2.38 µg/g) was significantly higher than that for females (0.96 ± 0.74 µg/g) (p < 0.01). Log transformed hair mercury concentration was significantly associated with the frequency of total seafood consumption (p < 0.01). Individuals who reported consuming seafood once a day or more were 3.71 (95% CI 0.84–16.38) times more likely to have a total hair mercury concentration over 1.0 µg/g, which corresponds approximately to the U.S. EPA reference dose, compared to those who consumed seafood once a week or less. Hair mercury concentration was also significantly higher among individuals who obtained all or most of their seafood from local recreational sources (p < 0.01). The elevated human mercury concentrations mirror the elevated concentrations observed in resident dolphins in the same geographical region. The current study is one of the first to apply the concept of a sentinel animal to a contiguous human population.
doi:10.3390/ijerph110706709
PMCID: PMC4113839  PMID: 24972033
mercury; dietary exposure; fish consumption; sentinel species; Florida; bottlenose dolphins
19.  Not all shellfish "allergy" is allergy! 
The popularity of shellfish has been increasing worldwide, with a consequent increase in adverse reactions that can be allergic or toxic. The approximate prevalence of shellfish allergy is estimated at 0.5-2.5% of the general population, depending on degree of consumption by age and geographic regions. The manifestations of shellfish allergy vary widely, but it tends to be more severe than most other food allergens.
Tropomyosin is the major allergen and is responsible for cross-reactivity between members of the shellfish family, particularly among the crustacea. Newly described allergens and subtle differences in the structures of tropomyosin between different species of shellfish could account for the discrepancy between in vitro cross-antigenicity and clinical cross-allergenicity. The diagnosis requires a thorough medical history supported by skin testing or measurement of specific IgE level, and confirmed by appropriate oral challenge testing unless the reaction was life-threatening.
Management of shellfish allergy is basically strict elimination, which in highly allergic subjects may include avoidance of touching or smelling and the availability of self-administered epinephrine. Specific immunotherapy is not currently available and requires the development of safe and effective protocols.
doi:10.1186/2045-7022-1-3
PMCID: PMC3294628  PMID: 22410209
20.  Nutritional Aspects in Diagnosis and Management of Food Hypersensitivity—The Dietitians Role 
Journal of Allergy  2012;2012:269376.
Many common foods including cow's milk, hen's egg, soya, peanut, tree nuts, fish, shellfish, and wheat may cause food allergies. The prevalence of these immune-mediated adverse reactions to foods ranges from 0.5% to 9% in different populations. In simple terms, the cornerstone of managing food allergy is to avoid consumption of foods causing symptoms and to replace them with nutritionally equivalent foods. If poorly managed, food allergy impairs quality of life more than necessary, affects normal growth in children, and causes an additional economic burden to society. Delay in diagnosis may be a further incremental factor. Thus, an increased awareness of the appropriate procedures for both diagnosis and management is of importance. This paper sets out to present principles for taking an allergy-focused diet history as part of the diagnostic work-up of food allergy. A short overview of guidelines and principles for dietary management of food allergy is discussed focusing on the nutritional management of food allergies and the particular role of the dietitian in this process.
doi:10.1155/2012/269376
PMCID: PMC3485989  PMID: 23150738
21.  Egg baked in product open oral food challenges are safe in selected egg-allergic patients 
Allergy & Rhinology  2014;5(2):e110-e112.
Egg allergy is one of the most common food allergies in children. Most egg-allergic children are able to tolerate egg baked in product (EBP) and will likely outgrow his/her egg allergy. By introducing EBP in the diet of an egg-allergic child, diet can be expanded and family stress can be reduced. Recent evidence suggests that children who tolerate EBP and continue to consume it will have quicker resolution of egg allergy than those who strictly avoid EBP; therefore, we aimed to evaluate the egg-allergic children who underwent EBP oral food challenge (OFC) in our allergy clinic to help define any specific predictors to be used in predicting the outcome of such challenges. We performed a retrospective chart review and 43 egg-allergic patients underwent EBP OFC in our outpatient allergy office from January 2011 to December 2012 were excluded. Nine patients who did not have a prior history of symptomatic egg ingestion. Clinical characteristics and laboratory findings of the remaining 34 patients were all recorded and analyzed. Of the remaining 34 patients, 22 (64.7%) were boys. Average age of first reaction to egg was 12.90 months, with average age at EBP OFC of 71.32 months. The average of the most recent skin-prick test wheal size was 10.10 mm and serum-specific IgE to egg white was 3.21 kU/L. Twenty-eight of the 34 patients (82.4%) passed the EBP OFC. Of the six patients who failed, none required epinephrine. After analysis of all of the clinical characteristics and laboratory findings, no risk factors, such as skin-prick test wheal size, were identified to be associated with an increased risk of failing EBP OFC. EBP OFC is a valuable tool to assess tolerance. As seen in our group of patients, the majority of egg-allergic patients pass EBP OFC. Thus, OFC should be considered as a clinical tool to expand a patient's diet and to improve quality of life as early as possible. Because we were unable to determine any clinical or laboratory predictors helpful to select egg-allergic patients who are likely to pass EBP OFC, additional prospective studies are necessary to determine the ideal egg-allergic patient who is likely to pass EBP OFC.
doi:10.2500/ar.2014.5.0092
PMCID: PMC4124576  PMID: 25198996
Baked egg; baked egg oral food challenge; egg allergy; egg baked in product; egg baked in product oral food challenge; food allergy; oral food challenge; serum-specific IgE; skin-prick testing
22.  Utility of penicillin allergy testing in patients presenting with a history of penicillin allergy 
Asia Pacific Allergy  2013;3(2):115-119.
Background
Current statistics show that approximately 10% of patients claim to be allergic to penicillin yet only 10% of these have demonstrable allergy. The most appropriate and cost-effective antibiotics are sometimes withheld on the basis of patient history of drug allergy.
Objective
Investigation of IgE hypersensitivity and delayed hypersensitivity in patients with a history of penicillin allergy to a teaching hospital allergy clinic.
Methods
Patients underwent skin prick and intradermal testing (IDT) with major and minor penicillin determinants. Those with negative skin tests were administered a three-day oral challenge. Demographic and clinical details about the reactions were noted.
Results
One hundred twenty eight patients underwent testing, of these, one hundred and ten had self-reported histories of penicillin allergy and eighteen were referred because of other antibiotic allergies. Seventeen patients with self-reported penicillin allergy had either positive skin tests or oral challenge results, corresponding to 15% of patients having proven allergy. None reacted on skin prick testing, four reacted to IDT, thirteen reacted to oral challenge (five immediate and eight delayed). Analysis of clinical histories showed that patients with a well-defined history of allergy and a history of anaphylaxis were more likely to have a positive test compared to patients with vague histories. Skin testing proved to be less sensitive than oral challenge.
Conclusion
A minority of patients presenting with a history of penicillin allergy have evidence of immune-mediated hypersensitivity (17/110, 15%) in this study. Of these, eight out of seventeen (47%) had delayed reactions, demonstrating the usefulness and discriminating power of objective testing, which must include three-day oral challenge. Discriminating factors for immune-mediated allergy from patient history were a clear description of the original reaction and a history of anaphylaxis. Negative allergy testing enables the use of penicillin as first-line treatment when necessary and this can significantly reduce costs of antibiotics.
doi:10.5415/apallergy.2013.3.2.115
PMCID: PMC3643063  PMID: 23667835
Penicillin allergy; Skin prick testing; Oral challenge
23.  Establishment of a seafood index to assess the seafood consumption in pregnant women 
Food & Nutrition Research  2013;57:10.3402/fnr.v57i0.19272.
Background
Seafood (fish and shellfish) is an excellent source of several essential nutrients for pregnant and lactating women. A short food frequency questionnaire (FFQ) that can be used to quantitatively estimate seafood consumption would be a valuable tool to assess seafood consumption in this group. Currently there is no such validated FFQ in Norway.
Objective
The objective of this study was to establish and validate a seafood index from a seafood FFQ against blood biomarkers (the omega-3 index, the omega-3 HUFA score, and serum 25OH vitamin D).
Design
We assessed maternal seafood consumption during the 28th gestation week in healthy Norwegian women (n=54) with a seafood FFQ. A seafood index was developed to convert ordinal frequency data from the FFQ into numerical scale data. The following blood biomarkers were used as a validation method: omega-3 index, omega-3 HUFA score, and the serum 25OH vitamin D.
Results
The reported frequency of seafood as dinner and as spread was strongly correlated with the estimated frequencies of seafood as dinner and as spread. This indicated that the seafood index is a valuable tool to aggregate reported frequencies from the seafood FFQ. The seafood index composed of the frequency of seafood consumption and intake of omega-3 supplements, termed the total seafood index, correlated positively with the omega-3 index, omega-3 HUFA score, and 25OH vitamin D.
Conclusion
We established and validated a seafood index from a seafood FFQ. The developed seafood index can be used when studying health effects of seafood consumption in large populations. This seafood FFQ captures seafood consumption and omega-3 supplement intake considerably well in a group of pregnant women.
doi:10.3402/fnr.v57i0.19272
PMCID: PMC3585774  PMID: 23467715
seafood consumption; marine omega-3 fatty acids; 25OH vitamin D; FFQ; biomarkers; pregnancy
24.  Food allergy knowledge, perception of food allergy labeling, and level of dietary practice: A comparison between children with and without food allergy experience 
BACKGROUND/OBJECTIVES
The prevalence of food allergies in Korean children aged 6 to 12 years increased from 10.9% in 1995 to 12.6% in 2012 according to nationwide population studies. Treatment for food allergies is avoidance of allergenic-related foods and epinephrine auto-injector (EPI) for accidental allergic reactions. This study compared knowledge and perception of food allergy labeling and dietary practices of students.
SUBJECTS/METHODS
The study was conducted with the fourth to sixth grade students from an elementary school in Yongin. A total of 437 response rate (95%) questionnaires were collected and statistically analyzed.
RESULTS
The prevalence of food allergy among respondents was 19.7%, and the most common food allergy-related symptoms were urticaria, followed by itching, vomiting and nausea. Food allergens, other than 12 statutory food allergens, included cheese, cucumber, kiwi, melon, clam, green tea, walnut, grape, apricot and pineapple. Children with and without food allergy experience had a similar level of knowledge on food allergies. Children with food allergy experience thought that food allergy-related labeling on school menus was not clear or informative.
CONCLUSION
To understand food allergies and prevent allergic reactions to school foodservice among children, schools must provide more concrete and customized food allergy education.
doi:10.4162/nrp.2015.9.1.92
PMCID: PMC4317486
Elementary students; food allergy; labeling; dietary practice
25.  Association between cancer and contact allergy: a linkage study 
BMJ Open  2011;1(1):e000084.
Background
Contact allergy is a prevalent disorder. It is estimated that about 20% of the general population are allergic to one or more of the chemicals that constitute the European baseline patch test panel. While many studies have investigated associations between type I allergic disorders and cancer, few have looked into the association between cancer and contact allergy, a type IV allergy. By linking two clinical databases, the authors investigate the possible association between contact allergy and cancer.
Methods
Record linkage of two different registers was performed: (1) a tertiary hospital register of dermatitis patients patch tested for contact allergy and (2) a nationwide cancer register (the Danish Cancer Register). After linking the two registers, only cancer subtypes with 40 or more patients registered were included in the analysis. The final associations were evaluated by logistic regression analysis.
Results
An inverse association between contact allergy and non-melanoma skin- and breast cancer, respectively, was identified in both sexes, and an inverse trend for brain cancer was found in women with contact allergy. Additionally, a positive association between contact allergy and bladder cancer was found.
Conclusion
The inverse associations support the immunosurveillance hypothesis (ie, individuals with an allergy are less likely to get cancer due to a triggered immune system), while the positive association with bladder cancer could be due to accumulations of chemical metabolites in the bladder. The authors' findings add to the limited knowledge about contact allergy and the risk of cancer.
Article summary
Article focus
Cancer and allergy have previously been shown to be associated. The associations are mostly inverse, adding weight to the theory that enhanced tumour immunosurveillance is present in allergic individuals.
The epidemiological studies showing these findings were predominantly on type I allergy; the present study investigated the association between type IV allergy and cancer.
Key messages
An association seemingly exists between contact allergy and cancer. In light of previous findings of an association between bladder cancer and hair-dye use, the association between bladder cancer and contact allergy we found is interesting.
Strengths and limitations of this study
This is a novel study investigating cancer and its possible association with a type IV allergy. The analysis was possible due to large, validated patient registers.
As this is not a prospective cohort study, it lacks the ability to prove causation.
doi:10.1136/bmjopen-2011-000084
PMCID: PMC3191431  PMID: 22021756

Results 1-25 (1111302)