Allergy, Asthma & Clinical Immunology - Latest Articles

Alterations in the complement cascade in post-traumatic stress disorder

Lilit Hovhannisyan — 2010-02-21T00:00:00Z

Background: In the present study we assessed the functional state of the major mediator of the immune response, the complement system, in post-traumatic stress disorder (PTSD). Methods: Thirty one PTSD patients within 13 years from traumatic event and the same number of sex- and age-matched healthy volunteers were involved in this study. In the blood serum of the study subjects hemolytic activities of the classical and alternative complement pathways, as well as the activities of the individual complement components have been measured. Correlation analysis between all measured parameters was also performed. Results: According to the results obtained PTSD is characterized by hyperactivation of the complement classical pathway, hypoactivation of the complement alternative pathway and overactivation of the terminal pathway. Conclusions: The results obtained provide further evidence on the involvement of the inflammatory component in pathogenesis of PTSD.

Skin prick testing in patients using beta-blockers: a retrospective analysis

Irene Fung — 2010-01-20T00:00:00Z

RationaleThe use of beta-blockers is a relative contraindication in allergen skin testing yet there is a paucity of literature on adverse events in this circumstance. We examined a population of skin tested patients on beta-blockers to look for any adverse effects. Methods: Charts from 2004-2008 in a single allergy clinic were reviewed for any patients taking a beta-blocker when skin tested. Data was examined for skin test reactivity, type of skin test, concomitant asthma diagnosis, allergens tested, and adverse events. Results: One hundred and ninety-one patients were taking beta-blockers when skin testing occurred. Seventy-two patients had positive skin tests. No tests resulted in an adverse event. Conclusions: This data demonstrates the relative safety of administrating of skin prick tests to patients on beta-blocker treatment. Larger prospective studies are needed to substantiate the findings of this study.

Panallergens and their impact on the allergic patient

Michael Hauser — 2010-01-18T00:00:00Z

The panallergen concept encompasses families of related proteins, which are involved in general vital processes and thus, widely distributed throughout nature. Plant panallergens share highly conserved sequence regions, structure, and function. They are responsible for many IgE cross-reactions even between unrelated pollen and plant food allergen sources. Although usually considered as minor allergens, sensitization to panallergens might be problematic as it bears the risk of developing multiple sensitizations. Clinical manifestations seem to be tightly connected with geographical and exposure factors. Future population- and disease-based screenings should provide new insights on panallergens and their contribution to disease manifestations. Such information requires molecule-based diagnostics and will be valuable for developing patient-tailored prophylactic and therapeutic approaches. In this article, we focus on profilins, non-specific lipid transfer proteins, polcalcins, and Bet v 1-related proteins and discuss possible consequences of panallergen sensitization for the allergic patient. Based on their pattern of IgE cross-reactivity, which is reflected by their distribution in the plant kingdom, we propose a novel classification of panallergens into ubiquitously spread "real panallergens" (e.g. profilins) and widespread "eurallergens" (e.g. polcalcins). "Stenallergens" display more limited distribution and cross-reactivity patterns, and "monallergens" are restricted to a single allergen source.

The anti-inflammatory effects of levocetirizine - are they clinically relevant or just an interesting additional effect

Garry Walsh — 2009-12-17T00:00:00Z

Levocetirizine, the R-enantiomer of cetirizine dihydrochloride has pharmacodynamically and pharmacokinetically favourable characteristics, including rapid onset of action, high bioavailability, high affinity for and occupancy of the H1-receptor, limited distribution, minimal hepatic metabolism together with minimal untoward effects. Several well conducted randomised clinical trials have demonstrated the effectiveness of levocetirizine for the treatment of allergic rhinitis and chronic idiopathic urticaria in adults and children. In addition to the treatment for the immediate short-term manifestations of allergic disease, there appears to be a growing trend for the use of levocetirizine as long-term therapy. In addition to its being a potent antihistamine, levocetirizine has several documented anti-inflammatory effects that are observed at clinically relevant concentrations that may enhance its therapeutic benefit. This review will consider the potential or otherwise of the reported anti-inflammatory effects of levocetirizine to enhance its effectiveness in the treatment of allergic disease.

Stem cells, inflammation and allergy

Marie-Renee Blanchet — 2009-12-07T00:00:00Z

Recently, many studies have suggested a potential role for early hematopoietic progenitor cell and hematopoietic stem cell (HSC) recruitment and differentiation in the development of allergy and inflammation. This is based largely on evidence that stem cells or CD34+ progenitor cells are recruited to the site of inflammation in allergic diseases, likely through many of the same adhesion and chemokine receptors used for stem cell homing to the bone marrow (PSGL-1, CXCL12, alpha4-beta1 integrin, CD44, etc). Once at the site of inflammation, it has been suggested that stem cells could participate in the perpetuation of inflammation by maturing, locally, into inflammatory cells in response to the growth factors released in situ. Here we provide a brief review of the evidence to suggest that hematopoietic stem and progenitor cells (versus mature hematopoietic lineages) are, indeed, recruited to the site of allergic inflammation. We also discuss the molecules that likely play a role in this process, and highlight a number of our novel observations on a specific role for the stem cell antigen CD34 in this process.

Hodgkin's lymphoma presenting with markedly elevated IgE: a case report

Anne Ellis — 2009-12-07T00:00:00Z

Background: Markedly elevated IgE as a manifestation of a lymphoproliferative disorder has been only rarely reported.Case PresentationWe present the case of a 22 year old female referred to the adult Allergy & Clinical Immunology clinic for an extremely elevated IgE level, eventually diagnosed with Hodgkin's lymphoma. She had no history of atopy, recurrent infections, eczema or periodontal disease; stool was negative for ova & parasites. Chest X-ray revealed large bilateral anterior mediastinal masses that demonstrated prominent uptake on gallium scan. Mediastinal lymph node biopsy was consistent with Hodgkin's lymphoma, nodular sclerosing subtype, grade I/II. Conclusion: Although uncommon, markedly elevated IgE may be a manifestation of a malignant process, most notably both Hodgkin's and Non-Hodgkin's lymphomas. This diagnosis should be considered in evaluating an otherwise unexplained elevation of IgE.

Importance of basophil activation testing in insect venom allergy

Mitja Kosnik — 2009-12-01T00:00:00Z

Background: Venom immunotherapy (VIT) is the only effective treatment for prevention of serious allergic reactions to bee and wasp stings in sensitized individuals. However, there are still many questions and controversies regarding immunotherapy, like selection of the appropriate allergen, safety and long term efficacy. Methods: Literature review was performed to address the role of basophil activation test (BAT) in diagnosis of venom allergy. Results: In patients with positive skin tests or specific IgE to both honeybee and wasp venom, IgE inhibition test can identify sensitizing allergen only in around 15% and basophil activation test increases the identification rate to around one third of double positive patients. BAT is also diagnostic in majority of patients with systemic reactions after insect stings and no detectable IgE. High basophil sensitivity to allergen is associated with a risk of side effects during VIT. Persistence of high basophil sensitivity also predicts a treatment failure of VIT. Conclusion: BAT is a useful tool for better selection of allergen for immunotherapy, for identification of patients prone to side effects and patients who might be treatment failures. However, long term studies are needed to evaluate the accuracy of the test.

Urticaria and infections

Bettina Wedi — 2009-12-01T00:00:00Z

Urticaria is a group of diseases that share a distinct skin reaction pattern. Triggering of urticaria by infections has been discussed for many years but the exact role and pathogenesis of mast cell activation by infectious processes is unclear. In spontaneous acute urticaria there is no doubt for a causal relationship to infections and all chronic urticaria must have started as acute. Whereas in physical or distinct urticaria subtypes the evidence for infections is sparse, remission of annoying spontaneous chronic urticaria has been reported after successful treatment of persistent infections. Current summarizing available studies that evaluated the course of the chronic urticaria after proven Helicobacter eradication demonstrate a statistically significant benefit compared to untreated patients or Helicobacter-negative controls without urticaria (p < 0.001). Since infections can be easily treated some diagnostic procedures should be included in the routine work-up, especially the search for Helicobacter pylori. This review will update the reader regarding the role of infections in different urticaria subtypes.

Treating rhinitis in the older population: special considerations

Raymond Slavin — 2009-12-01T00:00:00Z

Rhinitis in the elderly is a common but often neglected condition. Structural changes in the nose associated with aging, predisposes the elderly to rhinitis. There are a number of specific factors that affect medical treatment of the elderly including polypharmacy, cognitive dysfunction, changes in body composition, impairment of liver and renal function and the cost of medications in the face of limited resources. Rhinitis in the elderly can be placed in several categories and treatment should be appropriate for each condition. The most important aim is to moisten the nasal mucosa since the nose of the elderly is so dry. Great caution should be used in treatment with first generation antihistamines and decongestants. Medications generally well tolerated by the elderly are second generation antihistamines, intra-nasal anti-inflammatory agents, leukotriene modifiers and iprapropium nasal spray.

Introduction of oral vitamin D supplementation and the rise of the allergy pandemic

Matthias Wjst — 2009-11-19T00:00:00Z

The history of the allergy pandemic is well documented, enabling us to put the vitamin D hypothesis into its historical context. The purpose of this study is to compare the prevalence of rickets, vitamin D supply, and allergy prevalence at 50-year intervals by means of a retrospective analysis of the literature since 1880.English cities in 1880 were characterized by an extremely high rickets prevalence, the beginning of commercial cod liver oil production, and the near absence of any allergic diseases. By 1930 hay fever prevalence had risen to about 3% in English-speaking countries where cod liver oil was preferentially used for the treatment of rickets. In 1980 vitamin D was used nation-wide in all industrialized countries as supplement to industrial baby food, thus eradicating nearly all cases of rickets. At the same time the allergy prevalence reached an all-time high, affecting about 30% of the population.Time trends are therefore compatible with the vitamin D hypothesis although direct conclusions cannot be drawn. It is interesting, however, to note that there are at least two earlier research papers linking synthesized vitamin D intake and allergy (Reed 1930 and Selye 1962) published prior to the modern vitamin D hypothesis first proposed in 1999.