Search

International audience; Drug hypersensitivity reactions (DHRs) are a matter of great concern, both for outpatient and in hospital care. The evaluation of these patients is complex, because invivo tests have a suboptimal sensitivity and can be time-consuming, expensive and potentially risky, especially drug provocation tests. There are several currently available invitro methods that can be classified into two main groups: those that help to characterize the active phase of the reaction and those that help to identify the culprit drug. The utility of these invitro methods depends on the mechanisms involved, meaning that they cannot be used for the evaluation of all types of DHRs. Moreover, their effectiveness has not been defined by a consensus agreement between experts in the field. Thus, the European Network on Drug Allergy and Drug Allergy Interest Group of the European Academy of Allergy and Clinical Immunology has organized a task force to provide data and recommendations regarding the available invitro methods for DHR diagnosis. We have found that although there are many invitro tests, few of them can be given a recommendation of grade B or above mainly because there is a lack of well-controlled studies, most information comes from small studies with few subjects and results are not always confirmed in later studies. Therefore, it is necessary to validate the currently available invitro tests in a large series of well-characterized patients with DHR and to develop new tests for diagnosis.

Objectives and background: According to the World Health Organization (WHO) classification, the diagnosis of Systemic Mastocytosis (SM) relies on bone marrow (BM) examination and is based on a major and four minor criteria. The somatic ‘autoactivating’ point mutation D816V in the KIT receptor gene is one of the minor criteria, founded in the great majority of patients (90%) and it plays a central role in the pathogenesis of the disease. Indolent Systemic Mastocytosis (ISM) is the most common variant of SM, characterized by a very low MC burden and associated with very different clinical pictures. A highly sensitive diagnostic methods for D816V detection are required to assure an appropriate diagnosis and to reduce false-negative results. The recent development of “ultra-deep amplicon sequencing” (UDS) technologies has opened the way to a more accurate characterization of molecular aberrations with higher sensitivity of screening for known and unknown mutations. Our aims were: i) to set-up and optimize a UDS-based mutation screening strategy of the KIT gene on the Roche GS Junior Instrument; ii) to test the sensitivity of our UDS assay to detect the D816V mutation; iii) to investigate the presence of additional KIT mutations in SM. Methods: We decided to take advantage of a next generation sequencing approach to perform an UDS KIT gene mutation analysis on 20 bone marrow (BM) samples from patients whit ISM that were negative for the D816V mutation by Sanger Sequencing which has a sensitivity of 20%. Fusion primers were designed to generate ten partially overlapping amplicon covering the whole KIT transcript (exons 1-21) by RT-PCR. To determine the lower detection limit of our UDS-assay, serial dilutions of the HMC-1 cell line (harboring the D816V mutation) into an unmutated K562 cell line in ratios such as to simulate the following mutation loads were sequenced: 50%, 37.5%, 25%, 12.5%, 5%; 2.5%, 1.25%, 0.5%, 0.25%. Results and significance: UDS of cell line dilutions showed a high accuracy of D816V mutation detection and linearity of mutation calling over the entire range down to 0.25%. The UDS technology allowed to detected the D816V mutation, below the lower detection limit of Sanger Sequencing, with an abundance from 0.5% to 11%, in 12/20 ISM patients. Two additional sequence variations were detected in a large proportion of patients. These two variations included a 3bp in-frame deletion in exon 15 (GenBank X06182.1: c.2164_2166delAGC; p.S715del) found in 11/20 patients and a 12bp in frame-deletion in exon 9 in all patients, whit an abundance ranging from 83% to 97% (GenBank X06182.1: c.1550_1561delGTAACAACAAAG; p.G510_K513del). Previously published studies indicate that the KIT Gly-Asn-Asn-Lys510-513+/- alternatively spliced located immediately downstream to the extracellular KIT domain and KIT Ser715+/-, an interkinase KIT domain, are expressed in normal human hematopoietic cell, leukemic cell lines, acute myeloid leukemia blast and GISTs and represent rather a splice variant of KIT transcript. Interestingly our results showed the presence of the transmembrane domain M541L (GenBank X06182.1: c.1642A>C; p.Met541Leu) KIT-activating mutation in exon 10, with an abundance of 50%, in addition to D816V, in 2/20 ISM. This mutation is known to retain sensitivity to imatinib mesylate. Conclusions: Our preliminary results suggest that our-UDS based KIT gene mutation screening assay might be a reliable and sensitive alternative to conventional sequencing methods for the detection of the D816V. We are now planning to investigate whether the greater sensitivity of UDS allows to detect the D816V mutation in peripheral blood mononuclear cells from patients with a suspected clonal mast cell disorder. These results could represent a starting point to plan other extensive studies to better understand the exact role of KIT receptor alterations in SM. Supported by ELN, AIL, AIRC, PRIN, progetto Regione-Università 2010-12 (L. Bolondi), FP7 NGS-PTL project. Disclosures Cavo: Celgene: Consultancy, Honoraria, Speakers Bureau. Martinelli:Novartis: Consultancy, Speakers Bureau; BMS: Consultancy, Speakers Bureau; Pfizer: Consultancy; ARIAD: Consultancy.

Cutaneous lesions in patients with mastocytosis are highly heterogeneous and encompass localized and disseminated forms. Although a classification and criteria for cutaneous mastocytosis (CM) have been proposed, there remains a need to better define subforms of cutaneous manifestations in patients with mastocytosis. To address this unmet need, an international task force involving experts from different organizations (including the European Competence Network on Mastocytosis; the American Academy of Allergy, Asthma & Immunology; and the European Academy of Allergology and Clinical Immunology) met several times between 2010 and 2014 to discuss the classification and criteria for diagnosis of cutaneous manifestations in patients with mastocytosis. This article provides the major outcomes of these meetings and a proposal for a revised definition and criteria. In particular, we recommend that the typical maculopapular cutaneous lesions (urticaria pigmentosa) should be subdivided into 2 variants, namely a monomorphic variant with small maculopapular lesions, which is typically seen in adult patients, and a polymorphic variant with larger lesions of variable size and shape, which is typically seen in pediatric patients. Clinical observations suggest that the monomorphic variant, if it develops in children, often persists into adulthood, whereas the polymorphic variant may resolve around puberty. This delineation might have important prognostic implications, and its implementation in diagnostic algorithms and future mastocytosis classifications is recommended. Refinements are also suggested for the diagnostic criteria of CM, removal of telangiectasia macularis eruptiva perstans from the current classification of CM, and removal of the adjunct solitary from the term solitary mastocytoma., Supported by research grants from the German Research Council (DFG; HA 2393/6-1; CRC/SFB832, project A14; to K.H.); from the Division of Intramural Research, National Institute of Allergy and Infectious Diseases (to D.D.M.); and from the Austrian Science Funds (FWF; projects SFB F4611 and SFB F4707-B20; to P.V.). The Consensus Conference on Mastocytosis in Boston, Massachusetts (October 2012), was supported by the American Academy of Allergy, Asthma & Immunolog. A task force/consensus panel on mastocytosis between 2010 and 2012 was supported by the European Academy of Allergy and Clinical Immunology.

An anaphylactic reaction due to a Hymenoptera sting is a clinical emergency, and patients, their caregivers as well as all healthcare professionals should be familiar with its recognition and acute management. This consensus report has been prepared by a European expert panel of the EAACI Interest Group of Insect Venom Hypersensitivity. It is targeted at allergists, clinical immunologists, internal medicine specialists, pediatricians, general practitioners, emergency department doctors, and any other healthcare professional involved. The aim was to report the scientific evidence on self-medication of anaphylactic reactions due to Hymenoptera stings, to inform healthcare staff about appropriate patient self-management of sting reactions, to propose indications for the prescription of an adrenaline auto-injector (AAI), and to discuss other forms of medication. First-line treatment for Hymenoptera sting anaphylaxis is intramuscular adrenaline. Prescription of AAIs is mandatory in the case of venom-allergic patients who suffer from mast cell diseases or with an elevated baseline serum tryptase level and in untreated patients with a history of a systemic reaction involving at least two different organ systems. AAI prescription should also be considered in other specific situations before, during, and after stopping venom immunotherapy.

Mast cell activation syndrome (MCAS) can be diagnosed in patients with recurrent, severe symptoms from mast cell (MC)-derived mediators, which are transiently increased in serum and are attenuated by mediator-targeting drugs. When KIT-mutated, clonal MC are detected in these patients, a diagnosis of primary MCAS can be made. Severe systemic reactions to hymenoptera venom (HV) represent the most common form of anaphylaxis in patients with mastocytosis. Patients with primary MCAS and HV anaphylaxis are predominantly males and do not have skin lesions in the majority of cases, and anaphylaxis is characterized by hypotension and syncope in the absence of urticaria and angioedema. A normal value of tryptase (≤11.4 ng/ml) in these patients does not exclude a diagnosis of mastocytosis. Patients with primary MCAS and HV anaphylaxis have to undergo lifelong venom immunotherapy, in order to prevent further potentially fatal severe reactions.

Background The appropriate therapeutic management of patients with wasp-induced allergic reactions necessitates an accurate allergologic workup, entailing differentiation between sensitization against Vespula or Polistes venoms. Materials and methods We studied 52 consecutive adult subjects diagnosed with hypersensitivity to wasp venoms. Cap inhibition was performed using UniCAP Specific IgE. The concentration of serum IgE against two recombinant constituents of Antigen 5 (rVes v 5 and rPol d 5) was also measured using Immuno CAP 250. The ratio between values of specific IgE against recombinant allergens was calculated and a percentage difference > 50% was considered significant for specific immunization against one of the two venoms. Results The diagnostic agreement between recombinant allergens testing and CAP inhibition was 54% (kappa statistics, 0.34; 95% CI, 0.18–0.50) in the whole study population. In the 24 patients with recombinant allergens ratio > 50% and non dubious results of CAP inhibition assay the diagnostic agreement was perfect (100%; kappa of agreement, 1.00; 95% CI; 1.00–1.00). Discussion The results of this study show that the assessment of specific IgE against rVes v 5 and rPol d 5 may be regarded as a low-cost screening, providing valuable diagnostic information for differentiating the sensitization against Vespula or Polistes venoms. In patients with suggestive clinical history and ratio > 50% between specific IgE against rVes v 5 and specific IgE against and rPol d 5, the CAP inhibition assay may be safely withheld, thus allowing to achieve an early diagnosis at lower cost.

Mastocytosis is a rare condition characterized by abnormal mast cell proliferation and a broad spectrum of manifestations, including various organs and tissues. Osteoporosis is one of the most frequent manifestations of systemic mastocytosis, particularly in adults. Osteoporosis secondary to systemic mastocytosis is a cause of unexplained low bone mineral density that should be investigated when accompanied by suspicious clinical elements. Bone involvement is often complicated by a high recurrence of fragility fractures, mainly vertebral, leading to severe disability. The mechanism of bone loss is the result of different pathways, not yet fully discovered. The main actor is the osteoclast with a relative or absolute predominance of bone resorption. Among the stimuli that drive osteoclast activity, the most important one seems to be the RANK-RANKL signaling, but also histamine and other cytokines play a significant role in the process. The central role of osteoclasts made bisphosphonates, as anti-resorptive drugs, the most rational treatment for bone involvement in systemic mastocytosis. There are a few small studies supporting this approach, with large heterogeneity of drug and administration scheme. Currently, zoledronate has the best evidence in terms of gain in bone mineral density and bone turnover suppression, two surrogate markers of anti-fracture efficacy.

Midazolam is a short-acting benzodiazepine with a central nervous system depressing action. The pharmacologic properties of midazolam and its metabolites (similar to those of other benzodiazepines), include sedative, anxiolytic, amnesic and hypnotic activities. The favorable clinical aspects of the use of benzodiazepines are the result of a reversible allosteric interaction with the (gamma)-amino butyric acid (GABA) receptor A, that accounts for the major inhibitory neurotransmitter pathway within the central nervous system (1). This article is protected by copyright. All rights reserved.

Objective To study the diagnostic and treatment modalities used in drug allergy/hypersensitivity among members of the World Allergy Organization (WAO).Methods A questionnaire comprising 39 questions was circulated electronically to member societies, associate member societies, and regional and affiliate organizations of WAO between June 29, 2009, and August 9, 2009.Results Eighty-two responses were received. Skin testing was used by 74.7%, with only 71.4% having access to penicillin skin test reagents. In vitro-specific IgE tests were used by 67.4%, and basophil activation test was used by 54.4%. Lymphocyte transformation tests were used by 36.8% and patch tests by 54.7%. Drug provocation tests were used by 68.4%, the most common indication being to exclude hypersensitivity where history/symptoms were not suggestive of drug hypersensitivity/allergy (76.9%). Rapid desensitization for chemotherapy, antibiotics, or biologic agents was used by 69.6%. Systemic corticosteroid was used in the treatment of Stevens-Johnson syndrome by 72.3%, and high-dose intravenous immunoglobulins in toxic epidermal necrolysis by 50.8%. Human leukocyte antigen screening before prescription of abacavir was used by 92.9% and before prescription of carbamazepine by 21.4%.Conclusions Results of this survey form a useful framework for developing educational and training needs and for improving access to drug allergy diagnostic and treatment modalities across WAO member societies. Keywords: desensitization, drug allergy, hypersensitivity, skin tests

Purpose of review To analyse the association of systemic allergic hymenoptera sting reactions with mastocytosis and elevated baseline serum tryptase and to discuss diagnosis and treatment in patients with both diseases. Recent findings In recent large studies on patients with mastocytosis a much higher incidence of severe anaphylaxis following hymenoptera stings than in the normal population was documented. In patients with hymenoptera venom allergy, elevated baseline tryptase is strongly associated with severe anaphylaxis. Fatal sting reactions were reported in patients with mastocytosis, notably after stopping venom immunotherapy. During venom immunotherapy most patients with mastocytosis are protected from further sting reactions. Based on these observations immunotherapy for life is recommended for patients with mastocytosis and venom allergy. The incidence of allergic side-effects is increased in patients with mastocytosis and elevated baseline tryptase, especially in those allergic to Vespula venom. Premedication with antihistamines, or omalizumab in cases with recurrent severe side-effects, can be helpful. Summary In all patients with anaphylaxis following hymenoptera stings, baseline serum tryptase should be determined. A value above 11.4 microg/l is often due to mastocytosis and indicates a high risk of very severe anaphylaxis following re-stings. Venom immunotherapy is safe and effective in this situation.

BACKGROUND: Iodinated contrast media cause both immediate and nonimmediate hypersensitivity reactions. The aim of this prospective study was to determine the specificity and sensitivity of skin tests in patients who have experienced such reactions. METHODS: Skin prick, intradermal and patch tests with a series of contrast media were conducted in 220 patients with either immediate or nonimmediate reaction. Positive skin tests were defined according to internationally accepted guidelines. Seventy-one never-exposed subjects and 11 subjects who had tolerated contrast medium exposure, served as negative controls. RESULTS: Skin test specificity was 96-100%. For tests conducted within the time period from 2 to 6 months after the reaction, up to 50% of immediate reactors and up to 47% of nonimmediate reactors were skin test positive. For immediate reactors, the intradermal tests were the most sensitive, whereas delayed intradermal tests in combination with patch tests were needed for optimal sensitivity in nonimmediate reactors. Contrast medium cross-reactivity was more common in the nonimmediate than in the immediate group. Interestingly, 49% of immediate and 52% of nonimmediate symptoms occurred in previously unexposed patients. Many of these patients were skin test positive, indicating that they were already sensitized at the time of first contrast medium exposure. CONCLUSIONS: These data suggest that at least 50% of hypersensitivity reactions to contrast media are caused by an immunological mechanism. Skin testing appears to be a useful tool for diagnosis of contrast medium allergy and may play an important role in selection of a safe product in previous reactors.

Nonallergic hypersensitivity and allergic reactions are part of the many different types of adverse drug reactions (ADRs). Databases exist for the collection of ADRs. Spontaneous reporting makes up the core data-generating system of pharmacovigilance, but there is a large under-estimation of allergy/hypersensitivity drug reactions. A specific database is therefore required for drug allergy and hypersensitivity using standard operating procedures (SOPs), as the diagnosis of drug allergy/hypersensitivity is difficult and current pharmacovigilance algorithms are insufficient. Although difficult, the diagnosis of drug allergy/hypersensitivity has been standardized by the European Network for Drug Allergy (ENDA) under the aegis of the European Academy of Allergology and Clinical Immunology and SOPs have been published. Based on ENDA and Global Allergy and Asthma European Network (GA(2)LEN, EU Framework Programme 6) SOPs, a Drug Allergy and Hypersensitivity Database (DAHD((R))) has been established under FileMaker((R)) Pro 9. It is already available online in many different languages and can be accessed using a personal login. GA(2)LEN is a European network of 27 partners (16 countries) and 59 collaborating centres (26 countries), which can coordinate and implement the DAHD across Europe. The GA(2)LEN-ENDA-DAHD platform interacting with a pharmacovigilance network appears to be of great interest for the reporting of allergy/hypersensitivity ADRs in conjunction with other pharmacovigilance instruments.

Background Sublingual immunotherapy (SLIT) proved effective and safe in respiratory allergy, and thus its use in hymenoptera allergy can be hypothesized. Objective We sought to assess, in a proof-of-concept study, whether SLIT might potentially be beneficial in hymenoptera allergy. The sting challenge in large local reactions (LLRs) was used to test this hypothesis. Methods We performed a randomized, double-blind, placebo-controlled study involving patients with LLRs who were monosensitized to honeybee. After the baseline sting challenge, they were randomized to either SLIT or placebo for 6 months. The treatment (Anallergo, Florence, Italy) involved a 6-week build-up period, followed by maintenance with 525 μg of venom monthly. The sting challenge was repeated after 6 months. Results Thirty patients (18 male patients; mean age, 44.5 years) were enrolled, and 26 completed the study, with 1 dropout in the active group and 3 dropouts in the placebo group. In the active group the median of the peak maximal diameter of the LLRs decreased from 20.5 to 8.5 cm ( P = .014), whereas no change was seen in the placebo group (23.0 vs 20.5 cm, P = not significant). The diameter was reduced more than 50% in 57% of patients. One case of generalized urticaria occurred in a placebo-treated patient at sting challenge. No adverse event caused by SLIT was reported. Conclusion Honeybee SLIT significantly reduced the extent of LLRs, and its safety profile was good. Although LLRs are not an indication for immunotherapy, this proof-of-concept study suggests that SLIT in hymenoptera allergy deserves further investigation. Trials involving systemic reactions and dose-ranging studies are needed.

Background: Platinum salts can cause allergic sensitization. Recently, hypersensitivity reactions to oxaliplatin, the most recent platinum coordination complex introduced into clinical practice, have been reported. Objective: To validate and standardize skin tests to diagnose and possibly prevent hypersensitivity reactions to oxaliplatin. The secondary aims were to confirm IgE-mediated pathogenesis of the clinical manifestations and to evaluate skin tests to predict patients at risk of hypersensitivity reactions to oxaliplatin. Methods: We performed skin tests atincreasing concentrations of oxaliplatin on 15 patients never exposed to platinum salts, on 10 patients treated with oxaliplatin without any adverse reactions, and on 4 patients who had shown hypersensitivity reactions to the drug. Moreover we performed skin tests on 8 additional patients starting before the 5th dose and following a course of chemotherapy. Results: A positive skin reaction to the prick test at a concentration of 1 mg/ml was seen in 1 patient with hypersensitivity reactions. The intradermal test was positive in all the patients with hypersensitivity reactions at a concentration of 0.1 mg/ml. It was negative in the 15 nonexposed subjects, and in the 10 patients who had been exposed to oxaliplatin without hypersensitivity reactions. The skin test administered to patients before chemotherapy was positive in one case. Conclusion: A skin prick test at a concentration of 1 mg/ml and, in the case of a negative response, an intradermal test at the optimal concentration of 0.1 mg/ml should be used, starting from the 5th course of therapy, to diagnose and prevent hypersensitivity reactions to oxaliplatin.

Background Systemic mastocytosis is a clonal mast cell (MC) disease that can lead to potentially fatal anaphylactic reactions caused by excessive MC mediator release. The prevalence of mastocytosis in patients with Hymenoptera venom allergy is high, and thus the disease should be suspected in patients with severe reactions caused by Hymenoptera stings and increased serum basal tryptase (SBT) levels. Objective We sought to evaluate the presence of clonal MC disorders in patients seen at our mastocytosis center with Hymenoptera sting–induced anaphylaxis, documented hypotension, absence of urticaria pigmentosa, and normal SBT levels. Methods Twenty-two patients with Hymenoptera sting–induced anaphylaxis, without skin lesions, and with tryptase levels of less than 11.4 ng/mL underwent bone marrow evaluation. Bone mineral density was assessed in those patients with ascertained mastocytosis. Results In 16 of 22 patients, a diagnosis of indolent mastocytosis could be established, and 1 patient had a monoclonal MC activation syndrome. Patients with mastocytosis had higher SBT levels ( P = .03) but only rarely had angioedema/urticaria associated with hypotension ( P = .004). Conclusions The absence of urticaria or angioedema in severe reactions to Hymenoptera stings with hypotension might represent the most relevant factor in identifying patients with mastocytosis, regardless of their serum tryptase levels.

Patients with Systemic Mastocytosis (SM) need a highly sensitive diagnostic test for D816V detection of the KIT receptor gene.Along with histology/cytology and flow cytometry evaluation, bone marrow (BM) from 110 consecutive adult patients referred with a suspicion of SM to Multidisciplinary Outpatient Clinic for Mastocytosis in Verona were tested both by Amplification Refractory Mutation System Reverse Transcriptase quantitative real time Polymerase Chain Reaction (ARMS-RT-qPCR) and RT-PCR. +. Restriction Fragment Length Polymorphism (RFLP) followed by Denaturing-High Performance Liquid Chromatography (D-HPLC) and Sanger sequencing.ARMS-RT-qPCR identified D816V mutation in 77 patients, corresponding to 100% of cases showing CD25+ mast cells (MCs) whereas RT-PCR+RFLP/D-HPLC+sequencing revealed D816V mutations in 47 patients.According to the 2008 WHO criteria 75 SM, 1 Cutaneous Mastocytosis (CM), 1 monoclonal MC activation syndrome (MMAS), and 1 SM Associated with Haematologic Non-Mast Cell Disorder (SM-AHNMD) were diagnosed. Seventeen out 75 SM patients (23%) would have not satisfied sufficient WHO criteria on the basis of the sole RT-PCR+RFLP: these patients had significantly lower serum tryptase levels and amount of CD25+ MCs.Therefore, ARMS-RT-qPCR might result particularly useful, in patients that do not fulfil major BM histological criterion, for the recognition of indolent SM with a very low MC burden.

Hymenoptera venom allergy is a typical IgE-mediated reaction caused by sensitization to 1 or more allergens of the venom, and accounts for 1.5% to 34% of all cases of anaphylaxis. Patients suffering from mastocytosis are more susceptible to the anaphylactic reactions to an insect sting. This article aims to answer the most important clinical questions raised by the diagnosis and treatment of insect venom allergy in mastocytosis patients. Total avoidance of Hymenoptera is not feasible, and there is no preventive pharmacologic treatment available, although venom immunotherapy reduces the risk of subsequent systemic reactions.

Bone involvement is frequent in patients with systemic mastocytosis. Osteoporosis is the most prevalent bone manifestation, but diffuse osteosclerosis or focal osteolytic or osteosclerotic lesions are not infrequent. The risk of osteoporotic fractures is high, especially at the spine and in men. Routine measurements of bone mineral density and vertebral morphometry are warranted. The bone turnover markers indicate the involvement of complex bone metabolism in mastocytosis-related manifestations. Bisphosphonates represent the first-line treatment for osteoporosis-related mastocytosis.

Several hypersensitivity reactions (HSRs) to oxaliplatin have been reported. Presently, there is no reliable way to predict the development of this adverse reaction. The aim of the present study was to evaluate the reliability of skin tests in the detection of patients at risk of developing HSRs to oxaliplatin.Patients under treatment with oxaliplatin underwent the prick test at a concentration of 1 mg/ml and, if negative, intradermal injection at a concentration of 0.1 mg/ml, one hour before each course of oxaliplatin, starting from the second administration.A group of 101 patients were submitted to skin tests: two were positive, whereas five developed HSR despite negative tests (false-negative rate: 5.05%). These patients underwent desensitization, which permitted to conclude the planned schedule in five cases.A negative skin test to oxaliplatin has a good reliability in predicting HSRs. We suggest performing tests only in patients that have received at least five courses of oxaliplatin.

Background Standard venom immunotherapy involves the administration of the maintenance dose every 4 to 6 weeks. This regimen may have adherence problems, especially in the long term; thus, extended intervals have been proposed. Objective We prospectively compared the efficacy of 3- or 4-month extended maintenance dose vs the conventional regimen. Methods Patients receiving immunotherapy with a single venom were offered the extended maintenance dose (EMD) and were then followed up for field re-stings. Only the re-stings by the insect for which the patients received immunotherapy were considered. A comparable group of patients receiving the conventional maintenance dose (CMD) was used for comparison by logistic regression analysis. Results Seventy-six patients (60 male; mean age, 48 years) receiving the EMD were re-stung on 247 occasions by the insect for which they were receiving immunotherapy. The group receiving CMD included 110 patients (82 male; mean age, 44 years) certainly re-stung on 167 occasions by the specific insect. The percentage of re-sting without reaction was 93.5% in the EMD group and 81.5% in the CMD group, with a significant difference in favor of the former ( P =.001). At logistic regression analysis, only age, but not maintenance dose protocol, was predictive of subsequent systemic reactions. Conclusion The EMD is as effective and safe as the CMD. An increased maintenance seems to be the best option in term of convenience and economic savings.

Spanish Network on Mastocytosis (REMA): et al., [Background]: Indolent systemic mastocytosis (ISM) without skin lesions (ISMs-) shows a higher prevalence in males, lower serum baseline tryptase levels, and KIT mutation more frequently restricted to bone marrow (BM) mast cells (MCs) than ISM with skin lesions (ISMs+). Interestingly, in almost one-half of ISMs- patients, MC-mediator release episodes are triggered exclusively by insects. [Objective]: We aimed to determine the clinical and laboratory features of ISMs- associated with insect-induced anaphylaxis (insectISMs-) versus other patients with ISM. [Methods]: A total of 335 patients presenting with MC activation syndrome, including 143 insectISMs-, 72 ISMs- triggered by other factors (otherISMs-), 56 ISMs+, and 64 nonclonal MC activation syndrome, were studied. [Results]: Compared with otherISMs- and ISMs+ patients, insectISMs- cases showed marked male predominance (78% vs 53% and 46%; P, Supported by Fondo de Investigaciones Sanitarias –FIS– of the Instituto de Salud Carlos III, Ministery of Economy and Competitivity, Madrid, Spain grant PS09/00032; Fundación Sociosanitaria de Castilla-La Mancha grants 2010/008 and G-2010/ C-002; Fundacióon Española de Mastocitosis grant FEM 2011; BioB-HVS is supported by grant RETICS (Redes Temáticas de Investigación Cooperativa en Salud) RD09/ 00760074 (Toledo, Spain); RTICC (Red Temática de Investigación Cooperativa en Cáncer) grants RD09/0076/00133, RD12/0036/0048; FIS; FEDER, Ministery of Economy and Competitivity, Madrid, Spain grant PI11/02399; and Fundación Ramón Areces, Madrid, Spain grant CIVP16A1806; and by Associazione Italiana Leucemie e Linfomi of Verona (AIL-Verona) and ASIMAS (Associazione Italiana Mastocitosi). L. Escribano has been supported by one or more grants from Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Fundacion Sociosanitaria de Castilla La Mancha, and from FEM. A. García-Montero has been supported by one or more grants from ISCIII. M. Mollejo and A. Orfao have been supported by one or more grants from Instituto de Salud Carlos III, Ministerio de Economía y Competitividad. L. Sánchez-Muñoz has been supported by one or more grants from Fundacion Sociosanitaria de Castilla La Mancha.

Background A preferential association between systemic mastocytosis (SM) and hymenoptera allergy (HVA) has been observed. Patients with both diseases are at risk for more severe reactions, and venom immunotherapy (VIT) may represent a life-saving treatment, but the use of VIT in such patients raised concerns about its safety. Objective We evaluated a large population of patients with SM and HVA who received VIT. Methods This prospective study was performed in Italy and Spain. A diagnosis of SM and HVA and a VIT prescription were made according to international recommendations. The patients were carefully followed up during VIT, with special attention to field stings. Results A total of 84 patients (70 men, 14 women; mean age 52.1 years) were included, 81% with grade IV reaction, 91% with indolent SM. No difference was seen between the Italian and Spanish patients. There were 10 adverse reactions during the induction phase: 3 with the conventional induction and 7 with the rush-modified induction, none resulted in epinephrine administration and/or hospitalization. Fifty patients had one or more field re-sting (95 episodes), none during induction. The time elapsed from starting VIT and first re-sting was 2 months to 7 years, and the number of re-stings per patient was 1-6. Of the 50 patients who were re-stung, 43 (86%) resulted in being fully protected. Seven patients had reactions, and the maintenance dose was safely increased to 200 mcg. The maintenance dose interval was not different between patients with and those without reactions at re-stings. Conclusion VIT is well tolerated, safe, and effective in patients with SM.

Letter to the editor.-- et al.

Correspondence to the Editor.-- et al.

Purpose of review Mastocytosis in adults is associated with a history of anaphylaxis in 22-49%. In addition, monoclonal mast cell activation syndrome has been described presenting with anaphylaxis, especially in patients with hymenoptera venom anaphylaxis. Data on patients with drug hypersensitivity and mast cell diseases are scarce. Recent findings Drugs are elicitors of anaphylaxis in patients with mastocytosis. Drug hypersensitivity is only seldom described as associated with undetected mast cell disease in the literature. Together with a single-centred retrospective study, this data suggests that from all patients with drug-induced anaphylaxis, probably only a minority are associated with mast cell disease. Most of these cases in the literature are related to general anaesthesia. Thus, for patients with mastocytosis, general anaesthesia appears to be a procedure associated with risk of mast cell degranulation, and special precautions should be considered. Summary The association between immediate drug hypersensitivity and undetected mast cell diseases appears to be moderate, but nevertheless basal serum tryptase determination and examination for skin signs of mast cell disorders are recommended. An ongoing European multicenter study by the European Network for Drug Allergy will provide more information on this topic.

Background Systemic mastocytosis (SM) may be associated with hymenoptera allergy. In such cases, immunotherapy is a life-saving treatment, but a circumstantiated diagnosis is needed for its prescription. Patients with SM and previous reactions to stings, but with negative tests represent a diagnostic dilemma. The basophil activation test (BAT) may be helpful in refining the diagnosis. Objective We assessed the usefulness of BAT in subpopulations of mastocytosis patients, including those with negative tests for insect allergy. Methods Within a population of patients with mastocytosis and previous stings, we studied by BAT and augmented intradermal test (IDT) (10 µg/ml) two groups: (1) with reactions to stings and negative tests; (2) without reactions and negative tests. Basophil activation test was performed with different venoms, assessing at flow cytometry basophils’ activation. Results Sixty-three patients had mastocytosis and 52 had reactions to previous hymenoptera stings. Of them, seven proved negative to diagnostic tests. In six of seven of those patients, BAT was negative with all venoms, and in one, basophils resulted activated also with the negative control. In six patients without previous reactions and negative tests, BAT was totally negative in five of six patients and weakly positive to Hornet in one. Finally, the IDT at 10 µg/ml venom produced nonspecific positive results in most cases. Conclusion In patients with mastocytosis, the negative results of standard tests are reliable, because BAT and IDT at higher concentration do not add useful information.

In less than half a century, allergy, originally perceived as a rare disease, has become a major public health threat, today affecting the lives of more than 60 million people in Europe, and probably close to one billion worldwide, thereby heavily impacting the budgets of public health systems. More disturbingly, its prevalence and impact are on the rise, a development that has been associated with environmental and lifestyle changes accompanying the continuous process of urbanization and globalization. Therefore, there is an urgent need to prioritize and concert research efforts in the field of allergy, in order to achieve sustainable results on prevention, diagnosis and treatment of this most prevalent chronic disease of the 21st century.The European Academy of Allergy and Clinical Immunology (EAACI) is the leading professional organization in the field of allergy, promoting excellence in clinical care, education, training and basic and translational research, all with the ultimate goal of improving the health of allergic patients. The European Federation of Allergy and Airways Diseases Patients' Associations (EFA) is a non-profit network of allergy, asthma and Chronic Obstructive Pulmonary Disorder (COPD) patients' organizations. In support of their missions, the present EAACI Position Paper, in collaboration with EFA, highlights the most important research needs in the field of allergy to serve as key recommendations for future research funding at the national and European levels.Although allergies may involve almost every organ of the body and an array of diverse external factors act as triggers, there are several common themes that need to be prioritized in research efforts. As in many other chronic diseases, effective prevention, curative treatment and accurate, rapid diagnosis represent major unmet needs. Detailed phenotyping/endotyping stands out as widely required in order to arrange or re-categorize clinical syndromes into more coherent, uniform and treatment-responsive groups. Research efforts to unveil the basic pathophysiologic pathways and mechanisms, thus leading to the comprehension and resolution of the pathophysiologic complexity of allergies will allow for the design of novel patient-oriented diagnostic and treatment protocols. Several allergic diseases require well-controlled epidemiological description and surveillance, using disease registries, pharmacoeconomic evaluation, as well as large biobanks. Additionally, there is a need for extensive studies to bring promising new biotechnological innovations, such as biological agents, vaccines of modified allergen molecules and engineered components for allergy diagnosis, closer to clinical practice. Finally, particular attention should be paid to the difficult-to-manage, precarious and costly severe disease forms and/or exacerbations. Nonetheless, currently arising treatments, mainly in the fields of immunotherapy and biologicals, hold great promise for targeted and causal management of allergic conditions. Active involvement of all stakeholders, including Patient Organizations and policy makers are necessary to achieve the aims emphasized herein. ispartof: Clinical and Translational Allergy vol:2 issue:1 pages:21- ispartof: location:England status: published

The European Competence Network on Mastocytosis (ECNM) was initiated in 2002 as a multidisciplinary and multinational cooperative approach to increase awareness and to improve diagnosis and therapy of mastocytosis. The network is composed of local centers, physicians, and scientists who have dedicated their work to patients with mastocytosis. A strategic goal of the ECNM is to provide the best available information about the disease to patients and physicians. During the past 10 years, the ECNM has expanded to various countries and contributed successfully to the development of markers, definitions, and standards in the field of mastocytosis. Members of the ECNM organized Annual Meetings in Europe and two Working Conferences on Mastocytosis in Vienna (in 2005 and 2010), and initiated and supported several preclinical and clinical trials. In all these activities, representatives of the ECNM cooperate closely with their US colleagues, with patient-organizations in Europe and in the USA, and with other scientific networks. The ECNM also launched a mastocytosis registry that has been activated in 2012. Using the central database of this registry, cooperative multicenter studies, which should include sufficient numbers of patients and robust evaluations, will be conducted. These studies will increase our knowledge about optimal management and therapy of patients with mastocytosis in the future.

We systematically assessed bone mineral density (BMD), bone turnover markers (BTM), and fractures in a large cohort of patients with Indolent Systemic Mastocytosis (ISM).Eighty-two patients (mean age 48 years, 37 women) with ISM were studied. BMD was measured by dual X-ray absorptiometry at the lumbar spine and proximal hip. The serum markers of bone turnover included bone-specific alkaline phosphatase, C-telopeptides of type I collagen, and serum osteocalcin. Previous clinical fractures were registered and spine X-ray was obtained from all patients.Three women were excluded for concomitant diseases associated to osteoporosis. Osteoporosis according with the WHO classification (T-score-2.5) was found in 16 patients (20.0%) (7 females and 9 men). Mastocytosis-related low BMD (Z-score at either the spine or the hip-2) was found in 3 women (9%) and 13 men (28%). The BMD was generally lower at the spine than at the hip. No significant correlation was observed between serum tryptase levels and T or Z-score BMD. One or more moderate or severe vertebral fractures were found in 17 patients (12 men); in 11 of them Z-score values were-2 or not valuable at the spine. No significant difference was found in the prevalence of mastocytosis-related low BMD and/or vertebral fractures between patients with or without skin involvement. Two patients had radiographic and densitometric osteosclerosis-like characteristics. In osteoporotic patients higher, normal or lower serum BTM were found, without correlations with serum tryptase levels, while in patients with osteosclerosis both BTM and serum tryptase values were particularly increased.Vertebral osteoporosis and fractures are frequent in patients with ISM. Spine X-ray and densitometric examination are warranted in all patients, also without skin involvement and particularly in males; Z-score other than T-score BMD must be evaluated. Patients with idiopathic osteoporosis should be evaluated for mast cell disease. Both high than low BTM can be observed in patients with osteoporosis while osteosclerosis is characterized by high bone turnover and serum tryptase levels.

Systemic mastocytosis (SM) is a heterogeneous disorder characterized by the proliferation and accumulation of atypical mast cells (MC) in tissues, principally in the bone marrow (BM) and skin. The diagnosis of systemic mastocytosis requires the presence of multifocal dense mast cell infiltrates in

We are very grateful to Dr. Makras and Dr. Luis Escribano et al. for their comments about our letter "Isolated bone marrow mastocytosis: an underestimated subvariant of indolent systemic mastocytosis”.[1][1] The request of Dr. Makras for more information on skeletal involvement, which was not

Background: According to the World Health Organization (WHO) classification the diagnosis of systemic mastocytosis (SM) relies on bone marrow (BM) examination and is based on one major and four minor criteria. Herein, we used WHO criteria to compare flow cytometry (FC) with other available techniques in the diagnosis of SM after BM examination. Methods: We analyzed a cohort of 95 patients with suspect SM. All patients underwent comprehensive BM examination by using cytology, immunohistochemistry, FC and molecular study for mutation of c-Kit and serum tryptase dosage. FC evaluation was based on a combination of monoclonal antibodies, specifically CD25/CD2/CD45/CD34/CD117. Results: Seventy-four out of ninety-five patients were diagnosed with indolent SM (n = 59) or monoclonal mast cell activation syndrome (n = 15) because satisfying less than 3 minor criteria. Thirty-nine out of these seventy-four patients fulfilled the major histological criterion, whereas the presence of a minor criterion was assessed by FC, molecular study, cytology, and tryptase level in 70/74, 52/67, 56/74, and 42/74 patients, respectively. FC showed higher sensitivity than IHC in detection of CD25+ mast cells (MC) (92.9% vs. 73.8%; P = 0.019), especially in the absence of the major histological criterion (90.5% vs. 47.6%; P = 0.003). Moreover, CD2 expression was documented by FC and IHC in 97.1% and 35.3% of cases, respectively (P < 0.001). Conclusions: FC showed the best sensitivity for identifying abnormal MC compared to other techniques, especially in cases with low MC burden. Therefore, we hope for a major role of FC in the diagnostic work-up of clonal MC disorders. © 2011 International Clinical Cytometry Society

Summary Background: Cross-reactions between venoms may be responsible for multiple diagnostic positivities in hymenoptera allergy. There is limited data on the cross-reactivity between Vespula spp and Vespa crabro, which is an important cause of severe reactions in some parts of Europe. We studied by CAP-inhibition assays and immunoblotting the cross-reactivity between the two venoms. Methods: Sera from patients with non discriminative skin/CAP positivity to both Vespula and Vespa crabro were collected for the analyses. Inhibition assays were carried out with a CAP method, incubating the sera separately with both venoms and subsequently measuring the specific IgE to venoms themselves. Immunoblotting was performed on sera with ambiguous results at the CAP-inhibition. Results: Seventeen patients had a severe reaction after Vespa crabro sting and proved skin and CAP positive also to vespula. In 11/17 patients, Vespula venom completely inhibited IgE binding to VC venom, whereas VC venom inhibited binding to Vespula venom only partially (

Background: Specific IgG4 dosing against food is proposed to the public by a lot of commercial laboratories as a reliable method to diagnose food intolerance. Actually, few data on IgG4 responses to foods in adults are available in the literature. In this study we evaluated the clinical utility of specific IgG4 dosing against food in adult patients with suspected food allergy/intolerance. Methods: A case series of 73 adult patients with suspected food allergy and clinical manifestations of chronic urticaria or other allergy-supposed skin symptoms were tested for specific IgG4 against foods. An open food challenge was carried out for all IgG4-positive food. All positive open tests were controlled by double-blind placebo-controlled food challenge. Results: Forty-five patients (62%) were IgG4 positive for a number of foods, mainly egg, milk, casein and wheat. None of the patients with IgG4-positive testing showed adverse reactions, neither immediate nor delayed, to the corresponding food. Conclusions: In adult patients, testing for specific IgG4 lacks clinical utility for the diagnosis of food allergy or intolerance. Dosing of IgG4 should not be part of the diagnosis and therapy of adult patients with allergy-like skin diseases.

Polistes genus is widely spread in Europe and in the rest of the world. Polistes dominulus (PD), Polistes gallicus and Polistes nimphus are common in the Mediterranean area, where they are responsible for hymenoptera venom allergy. Until 1996, the only commercially available extract for diagnosis an

Background: The preferential association of mastocytosis with hymenoptera sting reactions is well known, but there is no data on the prevalence of clonal mast cell disorders in subjects with severe systemic reactions due to foods or drugs. Methods: Patients with food- or drug-induced severe systemic reactions, including anaphylaxis, and increased serum tryptase were studied for the presence of mastocytosis, and compared with a population of patients with hymenoptera allergy. The aetiological role of foods or drugs was assessed according to current recommendations. Systemic reactions were graded in severity according to the procedure described by Mueller. Serum tryptase was considered increased if the level was >11.4 ng/ml. Subjects with increased tryptase had dermatological evaluation and Bone marrow(BM) aspirate-biopsy, which included histology/cytology, flow cytometry and detection of KIT mutations. Results: A total of 137 subjects (57 male, mean age 42 years) were studied. Of them, 86 proved positive for drugs and 51 for foods. Overall, out of 137 patients, only nine (6.6%) had a basal tryptase >11.4 ng/ml, and only two (1.5%) were diagnosed with mastocytosis. This was clearly different from patients with hymenoptera allergy, where 13.9% had elevated tryptase and 11.1% had a clonal mast cell disorder. Conclusion: The association of clonal mast cell disorders with hymenoptera allergy seems to be more specific than that with food- or drug-induced systemic reactions.

Purpose of review Large local reactions (LLRs) caused by insect stings have attracted the interest of clinicians for decades, especially because of their possible role as risk factor for subsequent more severe reaction. Nonetheless, the literature on epidemiological and clinical aspects of LLR is fragmentary. Therefore, we aimed at reviewing the data available so far on the argument and the clinical implications. Recent findings Our knowledge on the epidemiology and risk factors of LLR relies on studies performed many years ago. All those studies and our personal observation agree on the fact that LLRs are followed by a systemic reaction in not a negligible proportion of patients (10-15%). More recent studies have underlined the possible role of specific immunotherapy, including sublingual, in the treatment and prevention of LLRs. Summary LLRs should deserve a detailed diagnostic work-up, just as for systemic reactions. The prescription of autoinjectable adrenaline would seem advisable. Specific research on the predictive role of LLR for systemic reactions is needed, as well as studies assessing the benefits of treating all patients with LLR with immunotherapy.

Background Anaphylaxis after Hymenoptera stings has been reported in subjects with mastocytosis, but few data exist regarding disease prevalence in populations allergic to these insects. Objective The incidence of clonal mast cell (MC) disorders in subjects with both systemic reactions to Hymenoptera stings and increased serum baseline tryptase (sBT) levels was assessed by using bone marrow (BM) aspirates and biopsy specimens. Methods Subjects with a history of a systemic reaction caused by a Hymenoptera sting underwent the standard diagnostic work-up for Hymenoptera allergy, and sBT levels were measured. Subjects with an increased sBT level had BM evaluation that included histology/cytology, flow cytometry, and detection of KIT mutations. Results Forty-four (11.6%) of 379 subjects with systemic reactions had increased sBT levels (>11.4 ng/mL), and 31 (70.5%) of these had a history of anaphylaxis. Thirty-four subjects with increased sBT levels underwent a BM analysis. Histology detected diagnostic or subdiagnostic MC infiltrates in 22 (65%) of 34 patients. Abnormal MCs were identified by means of flow cytometry and cytology in 26 (78.8%) of 33 and 20 (58.8%) of 34 subjects, respectively. A KIT mutation was detected in 17 (54.8%) of 31 subjects. The diagnosis was indolent systemic mastocytosis in 21 (61.7%) of 34 subjects and monoclonal MC activation syndrome in 9 (26.5%) of 34 subjects. All subjects with anaphylaxis had one of those 2 disorders. Conclusion The concomitant presence of systemic reactions (especially anaphylaxis) after Hymenoptera stings and increased sBT levels strongly suggests that a BM examination is indicated for the diagnosis of clonal MC disease.

Hymenoptera venom allergy (HVA) affects approximately 5% of the population1 and may provoke severe systemic or life-threatening reactions. A detailed diagnosis usually allows the allergen to be identified and a specific immunotherapy that confers an effective protection against stings to be prescribed.2 Much is known about the risk factors for HVA. Among these factors, the extent of exposure plays a major role, so that some categories of workers (eg beekeepers and gardeners) are at higher risk of sensitisation and clinical manifestations.3 Little is known about the quantitative relevance and relative weight as a risk factor of the different occupations and it is not known if there is a …

Background: Hymenoptera venom allergy can be effectively cured with specific immunotherapy, thus the correct identification of the allergen is essential. In the case of multiple skin and serum positivities it is important to know if a cross-reaction among venoms is present. We studied by CAP-inhibition assays the degree of cross-reactivity between Vespula vulgaris and Polistes dominulus. Methods: Serum samples were obtained from consecutive patients with a clinical history of grade III–IV reactions to hymenoptera sting and with nondiscriminative skin/CAP positivity to both Vespula and Polistes. Inhibition assays were carried out with a CAP method, incubating the sera separately with both venoms and subsequently measuring the specific immunoglobulin E (IgE) to venoms themselves. Results: Forty-five patients (33 male, mean age 40 years, age range 12–74, total serum IgE 242 ± 168 kU/l) were included. Their specific IgE to Vespula and Polistes were 12.03 ± 5.70 kU/l and 10.7 ± 2.0 kU/l (P = NS), respectively. At the CAP-inhibition assays, in 25 patients a >75% heterologous inhibition by P. dominulus venom against V. vulgaris-specific IgE was found. In six subjects V. vulgaris venom effectively inhibited the P. dominulus-specific IgE. In the remaining 14 cases the CAP-inhibition test provided intermediate and not discriminative results. Conclusion: In 31/45 patients, the double sensitizations to venoms were probably the result of cross-reactions and the CAP-inhibition allowed identifying the true double sensitizations. This approach may be helpful for the correct prescription of immunotherapy in the case of V. vulgaris and P. dominulus double positivity.

S U N D A Y 393 Drug Hypersensitivity Reactions in Patients with Clonal Mast Cells Disorders Carla Lombardo, Patrizia Bonadonna, MD, CME, Roberta Zanotti, Gianenrico Senna, MD, Giovanni Passalacqua, MD; Allergy Unit, Azienda ospedale Universit a di Verona, Italy, Allergy Unit of Azienda Ospedaliera Universitaria Integrata Allergy Unit, Verona, Italy, Department of Clinical and Experimental Medicine, Haematology Section, University of Verona, Italy, Allergy Unit, Verona, Italy, University of Genoa, Genoa, Italy. RATIONALE: The occurrence and characteristics of drug-induced anaphylaxis in patients with clonal mast cell disorders (CMD) is largely unknown. In this single-center study we assessed the prevalence of drug hypersensitivity in a population of mastocytosis patients. METHODS: All patients with ascertained CMD, followed in our clinic were asked to fill a questionnaire about previous adverse drug reactions. Patients with drug hypersensitivity underwent to oral challenge tests (OCT) with alternatives drug. RESULTS: 158 patients were enrolled; 89 (56.3%) male, mean age 52614 years. In 58.9% of patients the diagnosis of CMD was done after hymenoptera sting anaphylaxis, and in 7% after drug anaphylaxis. Fiftyone (32.3%) patients reported a total number of 78 drug hypersensitivity reactions, 16 (31.4%) had 2 or more episodes and 7 (13.7%) with different drug classes. The most frequently involved drugs were NSAIDs (54.9% of patients, 43 episodes), and antibiotics (41.2% of patients, 25 episodes). Anaphylaxis occurred in 11/28 (39%) patients with NSAIDs reactions and in 10/21 (47.6%) patients with antibiotics, mostly amoxicillin (66.7%). Thirty-eight OCTwith alternative NSAIDs (13 nimesulide, 14 etoricoxib, 6 meloxicam, 3 paracetamol and 2 aspirin) were performed and only 1 patient had rhinitis during aspirin challenge. Thirty-seven OCTs with antibiotics (15 clarithromycin, 13 ciprofloxacin, 2 clindamycin, 2 doxyciclin, 2 amoxicillin and 3 cefuroxime) were performed without adverse reactions. CONCLUSIONS: In our population the prevalence of self reported drug hypersensitivity was 32.3%, that is higher than in general population. The most involved drugs are antibiotics and NSAIDs. OCT with alternative drugs are safe and useful tools for a diagnosis.