Pseudoallergic reactions in chronic urticaria are associated with altered gastroduodenal permeability

Update on Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

Serum IgA contributes to the comprehension of Anisakis simplex associated chronic urticaria

The phenotype of allergic diseases associated with Anisakis determines the pattern of cytokines related to antibody production. However, the role of serum IgA and the immunomodulatory mechanisms exerted by active infection of L3 or passive mucosal contact with A. simplex specific antigens has not been studied before. We measured serum cytokine by flow cytometry (IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ, IL-17A, TGF-β1) and antibody levels (IgE, IgG4, IgA) by ELISA against total and excretory-secretory (ES) antigens, Ani s 3,and the group of major allergens Ani s 1, Ani s 7, and Ani s 13 in sera from 10 patients with gastro-allergic anisakiasis (GAA), 11 Anisakis sensitization associated chronic urticaria (CU+) as well as 17 non-Anisakis-sensitized patients with chronic urticaria (CU-), compared with the urticaria control group (18 subjects). Specific IgE, IgG4 and IgA were high in the GAA, but IgA levels were significantly higher in the CU+ with respect the CONTROL group. We observed higher levels of the ratio IgA/IgG4 in CU+ than GAA group for Ani s 1, Ani s 7, Ani s 13 and ES. Furthermore, chronic urticaria (CU) patients showed significant lower levels of IL-10, IFN-γ and IL-17A than patients without CU. The anti-Ani s 13 IgA/IgG4 ratio correlated positively with pro-inflammatory cytokines and ratios (TNF-α, IL-17A, Th17/Th2, Type1/Type2 and TNF-α/IL-10) in CONTROL group. In general, Anti-Anisakis IgA/G4 ratio was high in CU patients. In conclusion, this study demonstrates the importance of serum IgA because it is associated with chronic urticaria independently of Anisakis sensitization.

Gut microbiota facilitate chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) comes with gut dysbiosis, but its relevance remains elusive. Here we use metagenomics sequencing and short-chain fatty acids metabolomics and assess the effects of human CSU fecal microbial transplantation, Klebsiella pneumoniae, Roseburia hominis, and metabolites in vivo. CSU gut microbiota displays low diversity and short-chain fatty acids production, but high gut Klebsiella pneumoniae levels, negatively correlates with blood short-chain fatty acids levels and links to high disease activity. Blood lipopolysaccharide levels are elevated, link to rapid disease relapse, and high gut levels of conditional pathogenic bacteria. CSU microbiome transfer and Klebsiella pneumoniae transplantation facilitate IgE-mediated mast cell(MC)-driven skin inflammatory responses and increase intestinal permeability and blood lipopolysaccharide accumulation in recipient mice. Transplantation of Roseburia hominis and caproate administration protect recipient mice from MC-driven skin inflammation. Here, we show gut microbiome alterations, in CSU, may reduce short-chain fatty acids and increase lipopolysaccharide levels, respectively, and facilitate MC-driven skin inflammation.

Predictive Potential of Biomarkers of Intestinal Barrier Function for Therapeutic Management with Teduglutide in Patients with Short Bowel Syndrome

INTRODUCTION

The human intestinal tract reacts to extensive resection with spontaneous intestinal adaptation. We analyzed whether gene expression analyses or intestinal permeability (IP) testing could provide biomarkers to describe regulation mechanisms in the intestinal barrier in short bowel syndrome (SBS) patients during adaptive response or treatment with the glucagon-like peptide-2 analog teduglutide.

METHODS

Relevant regions of the GLP-2 receptor gene were sequenced. Gene expression analyses and immunohistochemistry were performed from mucosal biopsies. IP was assessed using a carbohydrate oral ingestion test.

RESULTS

The study includes 59 SBS patients and 19 controls. Increases in gene expression with teduglutide were received for sucrase-isomaltase, sodium/glucose cotransporter 1, and calcium/calmodulin serine protein kinase. Mannitol recovery was decreased in SBS but elevated with teduglutide (Δ 40%), showed a positive correlation with remnant small bowel and an inverse correlation with parenteral support.

CONCLUSIONS

Biomarkers predicting clinical and functional features in human SBS are very limited. Altered specific gene expression was shown for genes involved in nutrient transport but not for genes controlling tight junctions. However, mannitol recovery proved useful in describing the absorptive capacity of the gut during adaptation and treatment with teduglutide.

Potential Therapeutic Approaches for Chronic Urticaria: Beyond H1-Antihistamines and Biologics

Chronic urticaria is a disease that can significantly impact a patient's quality of life and ability to function. There are effective treatment options, such as nonsedating antihistamines or biologics, but some patients do not respond to these therapies, or the therapies are not available or affordable to all patients. This review aims to summarize potential treatment strategies for patients (1) who do not respond to antihistamines and (2) cannot readily access or do not respond to biologics. The review emphasizes the importance of sound clinical practice, including correct diagnosis of chronic urticaria phenotypes, treatment of associated comorbidities, and consideration of add-on pharmacological and nonpharmacological approaches. Although some treatments may lack high-quality evidence, they may still be justifiable in certain cases, provided that there is shared decision-making, regular reassessment, and early recognition of adverse events.

Urticaria and Angioedema

Urticaria and angioedema are caused by immunoglobulin E- and non-immunoglobulin E-mediated release of histamine and other inflammatory mediators from mast cells and basophils. Diagnosis is made clinically, and anaphylaxis must be ruled out if urticaria or angioedema is present. A limited nonspecific laboratory workup should be considered unless elements of the history or physical examination suggest specific underlying conditions. The mainstay of treatment is avoidance of triggers when and if triggers are identified. The first-line pharmacotherapy is second-generation H1 antihistamines, which can be titrated to greater than standard doses.

Nutrition and urticaria

Urticaria is a distressing dermatologic condition for many. Although the wheals of urticaria are characteristically evanescent, lasting less than 24 hours, patients tend to have recurrent episodes. Hives that last less than 6 weeks are considered acute urticaria. Acute urticaria does not routinely require supplementary work-up because the history often identifies a convincing, inciting allergen. Chronic urticaria is defined as episodes that occur for longer than 6 weeks, and there is often not an easily identifiable trigger. For both acute and chronic urticaria, patients frequently report food as a precipitating cause. For acute urticaria, the foods that are associated with true allergies, such as nuts and shellfish, are the most frequent offenders. The relationship between diet and chronic urticaria is not as firmly defined. Many patients unnecessarily restrict their diets, so it becomes the role of dermatologists to help patients identify if there is a reproducible link between their symptoms and their dietary exposures. The literature suggests that diets free from pseudoallergens and histamine-releasing foods may attenuate urticaria. Supplements such as fats, vitamin D, iron, and flavonoids have also been studied and may diminish symptoms.

Triggers of Exacerbation in Chronic Urticaria and Recurrent Angioedema-Prevalence and Relevance

Patients with urticaria and angioedema often have triggers that cause an outbreak or a swelling episode or worsen their chronic condition. Exploring these factors with each patient may result in better understanding and control of their disease. Patients should be advised to avoid known triggers, if feasible, or prepare to prevent or control an exacerbation with appropriate pretreatment if avoidance is not possible. In this review, we describe and discuss a variety of factors for which there is evidence that they cause or exacerbate chronic spontaneous urticaria and angioedema. These potentially exacerbating factors include drugs, food additives, and naturally occurring pseudoallergens, mental stress, and trauma.

The Interrelationships between Intestinal Permeability and Phlegm Syndrome and Therapeutic Potential of Some Medicinal Herbs

The gastrointestinal (GI) tract has an intriguing and critical role beyond digestion in both modern and complementary and alternative medicine (CAM), as demonstrated by its link with the immune system. In this review, we attempted to explore the interrelationships between increased GI permeability and phlegm, an important pathological factor in CAM, syndrome, and therapeutic herbs for two disorders. The leaky gut and phlegm syndromes look considerably similar with respect to related symptoms, diseases, and suitable herbal treatment agents, including phytochemicals even though limitations to compare exist. Phlegm may be spread throughout the body along with other pathogens via the disruption of the GI barrier to cause several diseases sharing some parts of symptoms, diseases, and mechanisms with leaky gut syndrome. Both syndromes are related to inflammation and gut microbiota compositions. Well-designed future research should be conducted to verify the interrelationships for evidence based integrative medicine to contribute to the promotion of public health. In addition, systems biology approaches should be adopted to explore the complex synergistic effects of herbal medicine and phytochemicals on conditions associated with phlegm and leaky gut syndromes.

Positive Effect of Helicobacter pylori Treatment on Outcome of Patients With Chronic Spontaneous Urticaria

OBJECTIVES

The association between Helicobacter pylori and chronic spontaneous urticaria (CSU) is controversial. Therefore, we aimed to directly diagnose H pylori by polymerase chain reaction (PCR) in gastric tissue from patients with CSU and to investigate the association between H pylori eradication therapy and CSU remission.

METHODS

Twenty-seven of 72 patients with CSU who were positive for H pylori stool antigen and PCR in gastric biopsy specimens were randomized to receive either anti-H pylori treatment or placebo.

RESULTS

Patients with H pylori were found to have significantly lower hemoglobin concentrations with microcytic hypochromic anemia and a significantly higher occurrence of dyspepsia symptoms. All H pylori-treated patients (except two) showed significant improvement of the urticaria itching and red wheals after 2 weeks of therapy compared with the placebo group (P < .001). The response rate to treatment was 85.7% (12 patients; 95% confidence interval, 64.3%-100.0%). The two patients who failed to eradicate H pylori had an H pylori strain resistant to amoxicillin.

CONCLUSIONS

An association was observed between CSU and presence of H pylori infection in the gastric tissue. Whether this is a causal relationship or not remains to be discovered, but treatment of H pylori can significantly improve the symptoms of CSU.

Peptic Ulcer Disease is Associated with Increased Risk of Chronic Urticaria Independent of Helicobacter pylori Infection: A Population-Based Cohort Study

BACKGROUND

Some studies showed patients with chronic urticaria have a higher rate of peptic ulcer disease (PUD). Whether PUD is a risk factor for chronic urticaria is unclear.

OBJECTIVE

The objective of this study was to evaluate the incidence of and risk factors for chronic urticaria in patients with PUD using the Taiwan National Health Insurance Research Database.

METHODS

We conducted a retrospective nationwide cohort study of the period 2000-2012 and involving 11,901 patients with PUD who underwent Helicobacter pylori (HP) therapy (PUD + HP group) and an equal number of matched patients without HP infection (PUD - HP group). Furthermore, we enrolled 23,802 patients without PUD for comparison (non-PUD group). The Cox proportional hazards regression model was used to analyze chronic urticaria risk after adjusting for potential confounding factors.

RESULTS

The mean ages of the three groups were around 50 years. Approximately 42.6% were female. Chronic urticaria incidences in the PUD + HP and PUD - HP groups were both significantly higher than that in the non-PUD group. The hazard ratios of chronic urticaria in the PUD + HP group and the PUD - HP group were 1.34 (95% confidence interval 1.09-1.64) and 1.45 (95% confidence interval 1.19-1.79), respectively. The risk difference became significant 2 years after patients with PUD had the HP infection tests and persisted till the end of follow-up. The risk increase was significant in patients with PUD who were female or aged 40-64 years. There was no difference in the risk comparison between PUD + HP and PUD - HP groups.

CONCLUSIONS

Peptic ulcer disease, independent of HP infection, is associated with an increased chronic urticaria risk. Patients with PUD who were female or aged 40-64 years are more likely to have chronic urticaria.

Urticaria and the gut

PURPOSE OF REVIEW

To review recent evidence on the association of urticaria and the gut diseases, focusing on the roles of chronic inflammation with or without Helicobacter pylori (H. Pylori) infection.

RECENT FINDINGS

The connection between the gut and urticaria has been discussed for a long time. Some publications have shown that H. pylori can induce chronic spontaneous urticaria (CSU). Recently, it was reported that upper gastrointestinal inflammatory disorders can cause CSU and trigger exacerbations independently of H. pylori.

SUMMARY

Gastritis and especially H. pylori-induced gastritis has been implicated as potential trigger of CSU. Chronic parasite infection and inflammation of the gut are relevant comorbidities and also potential inducing factors for the development of urticaria.

Systematic review and meta-analysis: Effect of Helicobacter pylori eradication on chronic spontaneous urticaria

BACKGROUND

Helicobacter pylori (HP) infection is considered to play a role in the pathogenesis of chronic spontaneous urticaria (CSU). However, the efficacy of HP eradication therapy on CSU symptom improvement has not been well established. This meta-analysis was conducted to estimate the association between HP infection and CSU and to evaluate whether HP eradication therapy benefits patients with CSU.

MATERIAL AND METHODS

In October 2018, we searched databases for studies investigating the efficacy of HP eradication therapy for patients with CSU. Risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using random effects models.

RESULTS

The meta-analysis included 22 studies with a total of 1385 patients with CSU. When comparing the spontaneous remission of urticarial symptom in patients with HP-positive to HP-negative patients, HP-negative patients showed significantly higher spontaneous remission of urticarial symptoms. (risk ratio 0.39; 95% confidence interval: 0.19-0.81). Among HP-positive CSU patients, remission of CSU was more likely shown in HP eradication therapy group compared to untreated group, aside from achieving HP elimination (risk ratio 2.10; 95% confidence interval: 1.20-3.68). However, there was no significant difference in the remission of CSU whether antibiotic therapy was successful in eradication of HP or not (risk ratio 1.00; 95% confidence interval: 0.65-1.54).

CONCLUSIONS

The results of this meta-analysis show that HP might be associated with the occurrence and persistence of CSU. The effectiveness of HP eradication therapy in suppressing CSU symptoms was significant. Interestingly, we found that resolution of CSU was not associated with successful eradication of HP infection. CSU Patients who were undergone antibiotic therapy for HP eradication showed significant higher CSU remission with or without HP eradication. Further studies are recommended to evaluate the mechanisms associated with relation of HP with CSU.

Is chronic urticaria more than skin deep?

Chronic urticaria is a disease characterized by the appearance of weals, angioedema or both longer than 6 weeks. Degranulation of cutaneous or submucosal mast cells leads to release of mediators including histamine resulting in redness, swelling and itch. Because mast cells are widely distributed throughout the body, the question is why they are not activated systemically or does systemic activation occur without overt end organ dysfunction? We have conducted an exploratory literature search for reports that have evidence of organ-specific dysfunction in chronic urticaria that might justify prospective observational studies. This search revealed some evidence of systemic effects of chronic urticaria in cardiac, respiratory, gastrointestinal, central nervous and musculo-skeletal systems. The relevance of these findings needs to be further determined. However, they justify prospective studies in larger numbers of patients and at different stages of disease activity.

Stress, pseudoallergens, autoimmunity, infection and inflammation in chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is often associated with organ specific autoimmunity but is rarely caused by food allergy. Colourings and preservatives in pre-packaged foods, so called pseudoallergens, have also been implicated. Factors that promote inflammation or reduce anti-inflammatory mechanisms may however, predispose susceptible individuals to CSU. Chronic underlying infection and mental and emotional stress can sometimes precede the onset of CSU and once established can exacerbate the symptoms. There is early evidence of dysbiosis within the gastrointestinal tract in people with CSU and reduced levels of vitamin D are also evident. The latter may be related to the importance of vitamin D3 in increasing T regulatory function which can control a tendency to autoimmunity. It is quite possible that a state of on-going chronic inflammation with reduced anti-oxidant mechanisms may underlie the not infrequent association between CSU and metabolic syndrome. Effective treatment of CSU should involve the use of anti-histamines, intermittent steroids and anti-IgE therapy. For recalcitrant disease immune modulatory therapy has a place. However, talking therapies that reduce stress and anxiety, vitamin D3 supplementation, correction of intestinal dysbiosis and treatment of any chronic infection should also be considered.

Diagnosis and treatment of urticaria in primary care

Urticaria, also known as hives among people, is a very common disease characterized by erythematous, edematous, itchy, and transient plaques that involve skin and mucous membranes. It is classified as acute spontaneous urticaria, chronic spontaneous urticaria, chronic inducible urticaria, and episodic chronic urticaria. Many factors such as infections, medicines, food, psychogenic factors, and respiratory allergens are accused of etiology, but sometimes, it is idiopathic. Clinical presentation involves red, swelling, and itchy plaques. The lesions usually resolve spontaneously within 2-3 h without a trace. The patients are sometimes confronted with an angioedema that can also involve the respiratory tract. In this case mucous membranes, such as eyelids, lips, swell with some pain and burning sensation. If respiratory tracts are involved, it may be life threatening and should be treated urgently. The diagnosis is usually straightforward, urticarial vasculitis, drug eruptions, viral eruptions, and urticaria pigmentosa must also be considered. H1 antihistamines and, sometimes, short-term systemic corticosteroids are preferred for the treatment; H2 antagonists may be added during resistant cases, although other treatment options, such as omalizumab, cyclosporine, and leukotriene receptor antagonists, may be considered during missed events.

NMR spectroscopy enables simultaneous quantification of carbohydrates for diagnosis of intestinal and gastric permeability

Increased intestinal or gastric permeability is one of the major hallmarks of liver cirrhosis. The current gold standard for diagnosis of aberrant gut permeability due to disease is the triple-sugar test, where carbohydrates are orally administered and urinary excretion is measured. Hereby, elevated lactulose levels indicate intestinal permeability, whereas increased sucrose levels reveal gastric permeability. However, reliable detection and quantification of these sugars in a complex biological fluid still remains challenging due to interfering substances. Here we used Nuclear Magnetic Resonance (NMR) spectroscopy with a simple and fast protocol, without any additional sample extraction steps, for straight-forward simultaneous quantification of sugars in urine in order to detect increased intestinal and gastric permeability. Collected urine samples were diluted in buffer and one- and two-dimensional proton spectra were recorded in order to reveal carbohydrate concentrations in individual urine samples containing mannitol, sucrose and/or lactulose. Overall, this article presents a fast and robust method for simultaneous quantification of different sugars down to low micro-molar concentrations for research studies and can be further extended for clinical studies with automation of the quantification process.

Nutrition therapy for adverse reactions to histamine in food and beverages

Adverse reactions to food are suspected in one third of the German population, but only 10% of these assumed hypersensitivity reactions can be clinically confirmed. While diagnosis of food allergies is fairly easy due to objective laboratory parameters, non-allergic hypersensitivity reactions are difficult to diagnose because these objective markers are lacking so far. Adverse reactions to histamine are often suspected to be the cause of a wide range of symptoms, especially when no allergic pathomechanism can be identified. In order to confirm such a suspicion, it is inevitable to validate a reproducible association between consumption of histamine-rich food and beverages and symptoms to identify causative agents and to exclude other disorders. Thereafter, avoidance tests should be performed on the basis of individual requirements. General advice with a lot of restraints is often unnecessarily strict. Nutrition therapy aims at a reduction of symptoms to a minimum while maintaining a high quality of life.

A Promoter Variant Within the Aryl Hydrocarbon Receptor Gene Is Associated with an Epithelial Barrier Defect in Smokers with Crohn's Disease

BACKGROUND

Smoking worsens Crohn's disease (CD). The aryl hydrocarbon receptor (AhR) is a transcription factor that mediates the toxicity of dioxinlike chemicals. We hypothesized that AHR variants and smoking influence CD.

METHODS

Exon-intron boundaries and coding and promoter regions of AHR gene were sequenced (28 patients with inflammatory bowel disease; 4 healthy controls). Two identified variants (rs7796976 and rs2066853) were studied for an association with intestinal permeability (IP, oral sugar test) in patients with inflammatory bowel disease (stratified according to the smoking status). AHR expression was analyzed by quantitative real-time polymerase chain reaction in colonic biopsies from patients with CD (n = 53). Case-control analysis including a genotype-phenotype correlation was performed for both variants (n = 767 patients with inflammatory bowel disease; n = 466 healthy controls).

RESULTS

Sequencing identified a putative promoter variant (rs7796976) and a nonsynonymous variant (rs2066853; Arg554Lys) in AHR, both predicted to be functionally relevant. The major G-allele of rs7796976 increased the risk for disturbed IP (odds ratio 1.9, 95% confidence interval [CI], 1.1-3.2) in CD but not ulcerative colitis. We observed an additive effect of the rs7796976 genotype and smoking on IP (P = 0.005), which was also shown for rs2066853 (P = 0.004; variants not linked). Both variants showed a genotype-dependent AHR expression in colonic biopsies of patients with CD. No overall association with either CD or ulcerative colitis was observed; however, the rs7796976 genotype and smoking increased the risk for the L4 phenotype in CD.

CONCLUSION

Smoking and functionally relevant AHR variants increase IP in CD. Because AhR is known to mediate between smoking and inflammation, these variants might be involved in the deleterious effect of smoking on CD.

Genes involved in the regulation of intestinal permeability and their role in ulcerative colitis

OBJECTIVE

Genome-wide association studies have identified single nucleotide polymorphisms in genes that might influence intestinal barrier function (HNF4A, ECM1, CDH1 and LAMB1) to increase the risk for ulcerative colitis (UC). The aim of our study was to detect causative sequence alterations and provide a functional link to a disturbed intestinal permeability (IP) in UC.

METHODS

A total of 19 UC patients with increased IP (lactulose/mannitol ratio measured by sugar drink test) were identified from a large database, and exon/intron boundaries, coding and promoter regions of HNF4A, ECM1, CDH1 and LAMB1 were sequenced. Variants with putative protein alterations were studied for an association with IP in 82 UC patients. A case-control analysis including a genotype phenotype correlation was performed in 743 patients with inflammatory bowel disease (IBD) and 473 healthy controls.

RESULTS

In UC patients, we identified 11 missense-mutations, 12 synonymous mutations, one putative promoter variant and three variants in introns close to the intron/exon boundaries (CDH1, HNF4A). For several variants prediction tools revealed damaging protein alterations. None of the studied variants, however, showed an association with an increased IP in UC. In the case-control analysis, the frequency of all investigated variants did not differ between UC or Crohn's disease and healthy controls. Furthermore, no significant association was found to a distinct phenotype.

CONCLUSIONS

Despite our large sequencing approach, we could not identify protein altering variants in the genes HNF4A, ECM1, CDH1 and LAMB1 which could explain an impaired intestinal barrier function in UC. The functional relevance of these genes in IBD remains unknown.

Relationship between Helicobacter pylori and idiopathic chronic urticaria: effectiveness of Helicobacter pylori eradication

INTRODUCTION

Chronic urticaria (CU) is defined as the presence of urticaria on most days of the week for a period of 6 weeks or longer. Some studies have reported an association between CU and Helicobacter pylori (H. pylori) infection.

AIM

To determine the prevalence of H. pylori infection using the stool antigen test in patients with idiopathic CU and to investigate the infected patients with CU following eradication of H. pylori.

MATERIAL AND METHODS

One hundred patients with idiopathic CU and 100 healthy controls were referred to our clinic between May 2012 and June 2013 and were tested for H. pylori antigen. The patients infected with H. pylori received quadruple therapy for 2 weeks. To assess eradication efficacy, a repeated H. pylori stool antigen test was performed in each patient 6 weeks after the end of anti-H. pylori therapy. The effectiveness of eradication therapy on CU was assessed 3 months after treatment.

RESULTS

Thirty-six percent patients with idiopathic CU were infected with H. pylori while 23% of the controls were infected. Response to eradication therapy was evident in 33 (91.67%) patients in whom H. pylori was eradicated while 3 (8.33%) patients showed no response despite eradication of H. pylori. Clinical follow-up of 33 successfully treated patients 3 months later revealed complete remission of urticaria in 54.5%, partial remission in 18.2%, and no improvement in 27.3%.

CONCLUSIONS

The results of our study suggest that H. pylori infection should be included in diagnostic workup of patients with no response to habitual treatment for CU or symptomatic gastrointestinal patients. For the diagnosis of H. pylori infection, one should consider the costs and accessibility of the population to the HpSA(®) stool antigen test and Urea breath test (UBT).

[Debating histamine intolerance: are adverse reactions to histamine-containing foods fact or fiction?]

Low-histamine diets are very popular and often self-imposed among people suspecting histamine intolerance. Most of these diets avoid a huge variety of foods containing more or less histamine, which has a considerable impact on their quality of life, but in most cases no long-term benefit. Underlying a diminished capacity for histamine degradation, the lack of partial or complete symptom improvement might be due to the fact that endogenous histamine release could also be responsible for symptoms. The role of ingested histamine-below the level for intoxication-is discussed controversially. However, it is obvious that the histamine content of a certain food alone is not enough to predict its tolerance. If histamine intolerance is suspected, an individual diagnostic and therapeutic procedure is mandatory in order to minimize avoidance and to preserve a high quality of life. Ideally this is done in a close cooperation between allergists and nutritionists.

Diet in dermatology: Part II. Melanoma, chronic urticaria, and psoriasis

The roles of dietary factors in aggravating, preventing, or treating skin diseases are common questions encountered in dermatology practice. Part II of this two-part series reviews dietary modifications that can potentially be utilized in the management of melanoma, chronic urticaria, and psoriasis patients. Specifically, we examine the effect of alcohol consumption and supplementation with vitamins D and E, polyunsaturated fatty acids, selenium, green tea, resveratrol, and lycopene on melanoma risk. The relationships between chronic urticaria symptoms and dietary pseudoallergens, gluten, and vitamin D are analyzed. We explore weight loss, reduced alcohol consumption, and gluten avoidance as means of reducing psoriasis-associated morbidity, as well as the possible utility of supplementation with polyunsaturated fatty acids, folic acid, vitamin D, and antioxidants. With proper knowledge of the role of diet in these cutaneous disease processes, dermatologists can better answer patient inquiries and consider implementation of dietary modifications as adjuncts to other treatments and preventative measures.

Myosin IXb variants and their pivotal role in maintaining the intestinal barrier: a study in Crohn's disease

BACKGROUND

Myosin IXb (MYO9B) is involved in the regulation of epithelial barrier function. We hypothesized that MYO9B variants are associated with increased intestinal permeability measured in patients with Crohn's disease (CD), where barrier dysfunction is crucially involved in disease development.

METHODS

We sequenced MYO9B and genotyped five MYO9B variants (rs1545620, rs1457092, rs2279003, rs2305764 and rs2279002) and correlated these data to measurement of intestinal permeability in German CD patients (n = 122) obtained by standard oral sugar test using the lactulose/mannitol ratio after measurement of urinary excretion. We furthermore studied MYO9B variants in three European cohorts with inflammatory bowel disease (IBD) and healthy controls : Germany (CD = 264; ulcerative colitis = 143 [UC]; HC = 372); Hungary (CD = 147; UC = 117; HC = 195), the Netherlands (CD = 157; HC = 219).

RESULTS

We found an association for four studied MYO9B variants to an increased intestinal permeability in CD patients (rs1545620, p = 0.010; rs1457092, p = 0.024; rs2279003, p = 0.003; rs2305764, p = 0.015). Furthermore, we observed significantly higher absolute values of intestinal permeability for individuals carrying risk alleles within MYO9B. Looking for an overall disease association, only the rs2305764 variant was associated with CD in the Dutch cohort (p = 0.004), but not in the German or Hungarian cohort. No association to UC or a distinct phenotype in both CD and UC patients was observed for all studied MYO9B variants.

CONCLUSION

Our data suggest a link between MYO9B variants to an increased intestinal permeability in CD patients. This supports the influence of Myosin IXb on the integrity of the epithelial barrier. The role of MYO9B variants in the overall susceptibility to IBD, however, remains to be elucidated.

Using a gluten oral food challenge protocol to improve diagnosis of wheat-dependent exercise-induced anaphylaxis

BACKGROUND

Oral wheat plus cofactors challenge tests in patients with wheat-dependent exercise-induced anaphylaxis (WDEIA) produce unreliable results.

OBJECTIVE

We sought to confirm WDEIA diagnosis by using oral gluten flour plus cofactors challenge, to determine the amount of gluten required to elicit symptoms, and to correlate these results with plasma gliadin levels, gastrointestinal permeability, and allergologic parameters.

METHODS

Sixteen of 34 patients with a history of WDEIA and ω5-gliadin IgE underwent prospective oral challenge tests with gluten with or without cofactors until objective symptoms developed. Gluten reaction threshold levels, plasma gliadin concentrations, gastrointestinal permeability, sensitivities and specificities for skin prick tests, and specific IgE levels were ascertained in patients and 38 control subjects.

RESULTS

In 16 of 16 patients (8 female and 8 male patients; age, 23-76 years), WDEIA was confirmed by challenges with gluten alone (n = 4) or gluten plus cofactors (n = 12), including 4 patients with previous negative wheat challenge results. Higher gluten doses or acetylsalicylic acid (ASA) plus alcohol instead of physical exercise were cofactors in 2 retested patients. The cofactors ASA plus alcohol and exercise increased plasma gliadin levels (P < .03). Positive challenge results developed after a variable period of time at peak or when the plateau plasma gliadin level was attained. Positive plasma gliadin threshold levels differed by greater than 100-fold and ranged from 15 to 2111 pg/mL (median, 628 pg/mL). The clinical history, IgE gliadin level, and baseline gastrointestinal level were not predictive of the outcomes of the challenge tests. The challenge-confirmed sensitivity and specificity of gluten skin prick tests was 100% and 96%, respectively.

CONCLUSION

Oral challenge with gluten alone or along with ASA and alcohol is a sensitive and specific test for the diagnosis of WDEIA. Exercise is not an essential trigger for the onset of symptoms in patients with WDEIA.

The EAACI/GA(2) LEN/EDF/WAO Guideline for the definition, classification, diagnosis, and management of urticaria: the 2013 revision and update

This guideline is the result of a systematic literature review using the 'Grading of Recommendations Assessment, Development and Evaluation' (GRADE) methodology and a structured consensus conference held on 28 and 29 November 2012, in Berlin. It is a joint initiative of the Dermatology Section of the European Academy of Allergy and Clinical Immunology (EAACI), the EU-funded network of excellence, the Global Allergy and Asthma European Network (GA(2) LEN), the European Dermatology Forum (EDF), and the World Allergy Organization (WAO) with the participation of delegates of 21 national and international societies. Urticaria is a frequent, mast cell-driven disease, presenting with wheals, angioedema, or both. The life-time prevalence for acute urticaria is approximately 20%. Chronic spontaneous urticaria and other chronic forms of urticaria do not only cause a decrease in quality of life, but also affect performance at work and school and, as such, are members of the group of severe allergic diseases. This guideline covers the definition and classification of urticaria, taking into account the recent progress in identifying its causes, eliciting factors and pathomechanisms. In addition, it outlines evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS).

Chronic idiophatic urticaria and Helicobacter pylori: a specific pattern of gastritis and urticaria remission after Helicobacter pylori eradication

Chronic urticaria (CU) is defined as the occurrence of spontaneous wheals for a duration of more than 6 weeks and is the most frequent skin disease, with prevalence ranging between 15 and 25%, and is a seriously disabling condition, with social isolation and mood changes causing a significant degree of dysfunction and quality of life impairment to many patients. The main clinical features of CU are the repeated occurrence of transient eruptions of pruritic wheals or patchy erythema on the skin that last less than 24 hours and disappear without sequelae. CU is often defined as chronic idiopathic urticaria (CIU) because the causes of CU remain unknown in the great majority (70-95%) of patients. Drugs, food, viruses, alimentary conservative substances or inhalant substances often seem to be involved in determining CIU skin flare. Despite a general agreement that bacteria infections and parasitic infestations can be involved in the pathogenesis of CIU, proven evidence of these relationships is lacking. The aim of the present study is to evaluate the prevalence of Helicobacter pylori (Hp) infection, and the extension and severity of gastritis in a group of CIU patients compared to controls and to evaluate the effectiveness of eradication of Hp on the CIU symptomatology, and the role of Hp infection in pathogenesis of CIU.

The JAK2 variant rs10758669 in Crohn's disease: altering the intestinal barrier as one mechanism of action

PURPOSE

The aetiology of intestinal barrier dysfunction in Crohn's disease (CD) is poorly understood. Associations in relatives of CD families suggest a genetic basis, but the relevant variants are still unknown. We hypothesized that variants in genes occurring in pathways such as autophagy and IL23 signalling might contribute to CD by altering intestinal permeability.

METHODS

We analysed five variants (rs10758669 within JAK2, rs744166 within STAT3, rs4958847, rs11747270 and rs13361189 within IRGM) in adult German inflammatory bowel disease patients (CD, n = 464; ulcerative colitis (UC), n = 292) and matched healthy controls (n = 508). These data were correlated with gastrointestinal permeability as assessed by lactulose/mannitol ratio in CD patients (n = 141) in remission.

RESULTS

Our data confirm the association between JAK2 rs10758669 (p = 0.026, OR = 1.25, 95% CI = 1.04-1.50) and STAT3 rs744166 (p = 0.04, OR = 0.83, 95% CI = 0.688-0.998) with CD, but not UC. With respect to all the analysed IRGM variants, no association was found to either CD or UC. Among CD patients, an increased intestinal permeability was detected in 65 out of 141 patients (46.1%). Most importantly, patients carrying the C risk allele within JAK2 rs10758669 displayed an increased permeability more often compared with patients without the C allele (p = 0.004). No association with intestinal permeability was found for STAT3 rs744166 and all IRGM variants.

CONCLUSIONS

JAK2 rs10758669 and STAT3 rs744166 increase susceptibility for CD. We show that the A>C substitution in rs10758669 of the JAK2 gene is associated with increased intestinal permeability. Altering intestinal barrier function might thus be one mechanism how JAK2 contributes to CD pathogenesis.

Hospitalization of Cuban children for giardiasis: a retrospective study in a paediatric hospital in Havana

The medical records of the 185 children who, in 2007, were admitted to the Academic Paediatric Hospital 'Centro Habana', in the Cuban capital of Havana, because of giardiasis were analysed retrospectively. A standardized form was used to collect data on the socio-demographic characteristics, clinical features, laboratory diagnosis, treatment and length of stay of each child. Information on the 15 children who had incomplete medical records was excluded from the data analysis. Of the remaining 170 children, 85 (50·0%) were aged 1-4 years, 97 (57·1%) were male, and 106 (62·4%), 92 (54·1%) and 69 (40·6%) had presented with diarrhoea, vomiting, and/or abdominal pain, respectively. Most (91·2%) of the cases had been diagnosed by the microscopical examination of a duodenal aspirate, and the drugs that had been most used frequently were quinacrine and tinidazole, which had been given to 72 (42·4%) and 62 (36·5%) of the cases, respectively. The mean length of hospital stay was 4·9 days. Such information on the clinical characteristics of giardiasis among children living in an endemic area may be valuable to paediatricians and public-health officials who wish to screen for the disease.

Possible links between intestinal permeability and food processing: A potential therapeutic niche for glutamine

Increased intestinal permeability is a likely cause of various pathologies, such as allergies and metabolic or even cardiovascular disturbances. Intestinal permeability is found in many severe clinical situations and in common disorders such as irritable bowel syndrome. In these conditions, substances that are normally unable to cross the epithelial barrier gain access to the systemic circulation. To illustrate the potential harmfulness of leaky gut, we present an argument based on examples linked to protein or lipid glycation induced by modern food processing. Increased intestinal permeability should be largely improved by dietary addition of compounds, such as glutamine or curcumin, which both have the mechanistic potential to inhibit the inflammation and oxidative stress linked to tight junction opening. This brief review aims to increase physician awareness of this common, albeit largely unrecognized, pathology, which may be easily prevented or improved by means of simple nutritional changes.

EAACI/GA(2)LEN/EDF/WAO guideline: definition, classification and diagnosis of urticaria

This guideline, together with its sister guideline on the management of urticaria [Zuberbier T, Asero R, Bindslev-Jensen C, Canonica GW, Church MK, Giménez-Arnau AM et al. EAACI/GA(2)LEN/EDF/WAO Guideline: Management of urticaria. Allergy, 2009; 64:1427-1443] is the result of a consensus reached during a panel discussion at the 3rd International Consensus Meeting on Urticaria, Urticaria 2008, a joint initiative of the Dermatology Section of the European Academy of Allergology and Clinical Immunology (EAACI), the EU-funded network of excellence, the Global Allergy and Asthma European Network (GA(2)LEN), the European Dermatology Forum (EDF) and the World Allergy Organization (WAO). Urticaria is a frequent disease. The life-time prevalence for any subtype of urticaria is approximately 20%. Chronic spontaneous urticaria and other chronic forms of urticaria do not only cause a decrease in quality of life, but also affect performance at work and school and, as such, are members of the group of severe allergic diseases. This guideline covers the definition and classification of urticaria, taking into account the recent progress in identifying its causes, eliciting factors, and pathomechanisms. In addition, it outlines evidence-based diagnostic approaches for different subtypes of urticaria. The correct management of urticaria, which is of paramount importance for patients, is very complex and is consequently covered in a separate guideline developed during the same consensus meeting. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS).

Urticaria : a review

Urticaria is often classified as acute, chronic, or physical based on duration of symptoms and the presence or absence of inducing stimuli. Urticarial vasculitis, contact urticaria, and special syndromes are also included under the broad heading of urticaria. Recent advances in our understanding of the pathogenesis of chronic urticaria include the finding of autoantibodies to mast cell receptors in nearly half of patients with chronic idiopathic urticaria. These patients may have more severe disease and require more aggressive therapies. Extensive laboratory evaluation for patients with chronic urticaria is typically unrevealing and there are no compelling data that associate urticaria with chronic infections or malignancy. Pharmacologic therapy consists primarily of the appropriate use of first- and second-generation histamine H(1) receptor antihistamines. Additional therapy may include leukotriene receptor antagonists, corticosteroids, and immunomodulatory agents for severe, unremitting disease. Despite our greater understanding of the pathogenesis of urticaria, the condition remains a frustrating entity for many patients, particularly those with chronic urticaria.

Diagnostic approach for suspected pseudoallergic reaction to food ingredients

Chronic urticaria, recurrent angioedema and non-allergic asthma have all been associated with pseudoallergic reactions to food ingredients. For atopic dermatitis and diseases of the gastrointestinal tract, this association is controversial. Pseudoallergic reactions can be elicited by additives as well as by natural food ingredients. An altered histamine metabolism may be associated with pseudoallergy. Acute urticaria or a short episode of angioedema is not an indication for exhaustive evaluation. If basic diagnostic screening is negative in chronic urticaria, a low-pseudoallergen diet can be considered. Skin and serological tests are not objective diagnostic parameters for pseudoallergic reactions. The severity of symptoms should be documented while the patient is on a low-pseudoaller-gen diet. Oral provocation with additives leads to reproducible symptoms only in a few cases. Therefore, if a low-pseudoallergen diet brings improvement, the patient is then exposed to a pseudoallergen-rich "super meal". After a positive reaction to the "super meal" the challenge with additives takes place in the form of collective group exposition. When the patient has asthma or a history of anaphylac-toid reactions, testing with individual substances in carefully increasing dosages is required. The suspicion of adverse reactions against histamine can be confirmed by a challenge with histamine dihydrochloride. In the case of respiratory symptoms, provocation by inhalation should be considered. Objectifying symptoms especially in gastrointestinal diseases is mandatory and should include double-blind placebo-controlled food challenge, if possible.

Altered intestinal permeability in patients with primary fibromyalgia and in patients with complex regional pain syndrome

OBJECTIVES

The pain intensity of patients with FM has recently been reported to be correlated with the degree of small intestinal bacterial overgrowth (SIBO). SIBO is often associated with an increased intestinal permeability (IP). Increased IP, if shown in FM, may have pathogenetic relevance because it leads to the exposure of immune cells to luminal antigens and consequent immune modulation. It is currently unknown whether IP is altered in FM. We therefore examined the IP in a group of patients with primary FM and in two control groups, healthy volunteers and patients with an unrelated chronic pain syndrome, complex regional pain syndrome (CRPS). We hypothesized that patients with FM, but not volunteers or those patients with CRPS, would have altered IP.

METHODS

Both gastroduodenal and small IP were assessed using an established three-sugar test, where urinary disaccharide excretion reflecting intestinal uptake was measured using HPLC.

RESULTS

Forty patients with primary FM, 57 age- and sex-matched volunteers and 17 patients with CRPS were enrolled in this study. In the FM group, 13 patients had raised gastroduodenal permeability and 15 patients had raised small intestinal permeability, but only one volunteer had increased gastroduodenal permeability (P < 0.0001, chi-square test for the three groups). The IP values were significantly increased in the patient groups (P < 0.0003 for all comparisons, one-way analysis of variance).

CONCLUSIONS

The IPs in primary FM and, unexpectedly, CRPS are increased. This study should stimulate further research to determine the implication of altered IP in the disease pathophysiology of FM and CRPS.

Altered intestinal function in patients with chronic heart failure

OBJECTIVES

We evaluated morphology and function of the gut in patients with chronic heart failure (CHF).

BACKGROUND

Intestinal translocation of bacterial endotoxin may contribute to the inflammatory state observed in patients with CHF. The morphology and function of the gut may be abnormal.

METHODS

We studied 22 patients with CHF (age 67 +/- 2 years, left ventricular ejection fraction [LVEF] 31 +/- 1%, New York Heart Association functional class 2.3 +/- 0.1, peak VO2 15.0 +/- 1.0 ml/kg/min) and 22 control subjects (62 +/- 1 years, LVEF 68 +/- 2%, peak VO2 24.7 +/- 1.3 ml/kg/min). Bowel wall thickness was assessed by transcutaneous sonography, small intestinal permeability by the lactulose-mannitol test, passive carrier-mediated transport by D-xylose test, large intestinal permeability by sucralose test (5- and 26-h urine collection, high-performance liquid chromatography), and mucosal bacterial biofilm by fluorescence in situ hybridization in biopsies taken during sigmoidoscopy.

RESULTS

Chronic heart failure patients, compared with control patients, showed increased bowel wall thickness in the terminal ileum (1.48 +/- 0.16 mm vs. 1.04 +/- 0.08 mm), ascending colon (2.32 +/- 0.18 mm vs. 1.31 +/- 0.14 mm), transverse colon (2.19 +/- 0.20 vs. 1.27 +/- 0.08 mm), descending colon (2.59 +/- 0.18 mm vs. 1.43 +/- 0.13 mm), and sigmoid (2.97 +/- 0.27 mm vs. 1.64 +/- 0.14 mm) (all p < 0.01). Chronic heart failure patients had a 35% increase of small intestinal permeability (lactulose/mannitol ratio: 0.023 +/- 0.001 vs. 0.017 +/- 0.001, p = 0.006), a 210% increase of large intestinal permeability (sucralose excretion: 0.62 +/- 0.17% vs. 0.20 +/- 0.06%, p = 0.03), and a 29% decrease of D-xylose absorption, indicating bowel ischemia (26.7 +/- 3.0% vs. 37.4 +/- 1.4%, p = 0.003). Higher concentrations of adherent bacteria were found within mucus of CHF patients compared with control subjects (p = 0.007).

CONCLUSIONS

Chronic heart failure is a multisystem disorder in which intestinal morphology, permeability, and absorption are modified. Increased intestinal permeability and an augmented bacterial biofilm may contribute to the origin of both chronic inflammation and malnutrition.

Intestinal permeability in patients with adverse reactions to food

BACKGROUND

An abnormal intestinal permeability could contribute to establish an altered sensitivity to food-allergen.

AIM

To evaluate the intestinal permeability in subjects with adverse reactions to food on allergen-free diet.

SUBJECTS

Twenty-one patients with food allergy and 20 with food hypersensitivity on allergen-free diet were enrolled and divided in four groups according to the seriousness of their referred clinical symptoms when they were on a free diet.

METHODS

Intestinal permeability was evaluated by Lactulose/Mannitol ratio urinary detection determined by anion-exchange chromatography.

RESULTS

Statistically significant different Lactulose/Mannitol ratio was evidenced in subjects with food allergy (p=0.003) or hypersensitivity (p=0.0008) compared to control patients. The correlation between Lactulose/Mannitol ratio and the seriousness of clinical symptoms, by using Spearman test, was statistically significant for food allergy (p=0.0195) and hypersensitivity (p=0.005) patients.

CONCLUSIONS

The present data demonstrate that impaired intestinal permeability, measured in our conditions, is present in all subjects with adverse reactions to food. In addition, for the first time, we report a statistically significant association between the severity of referred clinical symptoms and the increasing of Intestinal Permeability Index. These data reveal that intestinal permeability is not strictly dependent on IgE-mediated processes but could better be related to other mechanisms involved in early food sensitisation, as breast-feeding, or microbial environment that influence the development of oral tolerance in early infancy.