Immunologic responses to the major allergen of Olea europaea in local and systemic allergic rhinitis subjects

OBJECTIVE

To evaluate the in vivo and in vitro responses to nOle e 1 in allergic rhinitis (AR) and local allergic rhinitis (LAR) patients sensitized to olive tree pollen (OL) confirmed by nasal allergen provocation test (NAPT).

METHODS

Twelve subjects with AR, 12 with LAR and 12 subjects as control group (CG) were selected. Skin testing and NAPT with nOle e 1 were performed. Eosinophilic cationic protein (ECP) and tryptase were measured in nasal lavages before and after NAPT. Serum IgE to OL allergens was measured by ELISA. Basophil activation tests (BAT) with OL and nOle e 1 and dendritic cell maturation/proliferation studies were carried out.

RESULTS

All AR (12/12) and 10/12 (83%) of LAR had a +NAPT to nOle e 1. ECP levels in nasal lavages were significantly increased after NAPT in both AR and LAR compared with CG at 15 min (P < 0.05). Serum IgE was positive only in AR. All AR had +BAT responses to OL and 10/12 to nOle e 1 (83%); 8/12 LAR (66.6%) had a +BAT to OL and 4/12 (33%) to nOle e 1, with only one subject of the CG with a +BAT to both OL and nOle e 1 (8%). Dendritic cell proliferation to nOle e 1 was increased in AR compared to LAR and CG (P = 0.019 and P = 0.001, respectively).

CONCLUSION

Both AR and LAR had a similar in vivo response to nOle e 1 with release of inflammatory mediators. Specific basophil activation with OL and nOle e 1 was observed in LAR confirming previous data obtained with dust mites.

Nosocomial Outbreak of Pseudomonas aeruginosa Endophthalmitis

We describe an outbreak of nosocomial endophthalmitis due to a common source, which was determined to be trypan blue solution prepared in the hospital's pharmacy service. We assume that viable bacteria probably gained access to the trypan blue stock solution during cooling after autoclaving. The temporal cluster of Pseudomonas aeruginosa endophthalmitis was readily perceived on the basis of clinical and microbiological findings, and an exogenous source of contamination was unequivocally identified by means of DNA fingerprinting.

Initial immunological changes as predictors for house dust mite immunotherapy response

BACKGROUND

Although specific immunotherapy is the only aetiological treatment for allergic disorders, the underlying mechanisms are not fully understood. Specific immunotherapy induces changes in lymphocyte Th subsets from Th2 to Th1/Treg. Whether differences in immunological patterns underlie patient response to immunotherapy has not yet been established.

OBJECTIVES

We studied the immunological changes occurring during a 1-year period of Dermatophagoides pteronyssinus (DP) immunotherapy and their relation with clinical outcome.

METHODS

We included 34 patients with DP allergy who received subcutaneous specific immunotherapy (SCIT) for 1 year. Following treatment, patients were classified as responders or non-responders. Fourteen allergic subjects who did not receive SCIT were included as controls. Peripheral blood was obtained at 0, 1, 3, 6 and 12 months and cultured with nDer p 1. Phenotypic changes, cytokine production and basophil response were analysed by flow cytometry; transcription factors were measured by mRNA quantification. Serum immunoglobulin levels were also measured.

RESULTS

After 1 year of SCIT, 82% of cases showed improved symptoms (responders). Although increases in sIgG4 were observed, BAT reactivity was not modified in these patients. Increases in T-BET/FOXP3 as well as nDer p 1-specific Th1/Treg frequencies were also observed, along with a decrease in Th2, Th9 and Th17. These changes corresponded to changes in cytokine levels.

CONCLUSION

Patients who respond well to DP-SCIT show immunological differences compared to non-responders. In responders, basal differences include a lower frequency of Th1 and higher frequencies of Th2, Th9 and Th17 cells. After 1 year of treatment, an increased production of sIgG4 was observed in responders, along with a change in Th2 response towards Th1/Treg.

Role of Histamine Release Test for the Evaluation of Patients with Immediate Hypersensitivity Reactions to Clavulanic Acid

BACKGROUND

Immediate hypersensitivity reactions to clavulanic acid (CLV) seem to be on the increase. Diagnosis is mainly based on skin testing and the drug provocation test (DPT), procedures that are not risk free. The aim of this study was to evaluate whether the histamine release test (HRT) could help evaluate patients with selective hypersensitivity to CLV.

METHODS

Eighteen patients with immediate selective hypersensitivity reactions to CLV (positive skin tests to CLV but negative to the major and minor determinants of benzylpenicillin and amoxicillin; negative DPT to benzylpenicillin and amoxicillin) and 21 controls with tolerance to CLV were included. Direct and passive HRT, using patient whole blood or 'IgE-stripped' donor blood sensitized by patient serum, respectively, were performed by stimulating the blood with CLV, and basophil histamine release was detected by fluorometric determination.

RESULTS

The clinical symptoms were anaphylaxis (n = 6), urticaria (n = 9) and urticaria-angioedema (n = 3). The median time interval between the reaction and the study was 225 days (interquartile range, IQR: 120-387.5) and between drug intake and the development of symptoms 30 min (IQR: 6.25-30). We obtained similar data for both the direct and passive HRT, with a sensitivity and specificity of 55 and 85%, respectively, a positive predictive value of 76% and a negative predictive value of 69%.

CONCLUSIONS

The sensitivity of both the direct and passive HRT for diagnosing patients with immediate allergy to CLV is less than 60%. However, the passive HRT has the advantage that it is based on the testing of serum samples that can be handled more easily than fresh blood samples.

Environmental Presence of Mycobacterium tuberculosis Complex in Aggregation Points at the Wildlife/Livestock Interface

The members of the Mycobacterium tuberculosis complex (MTC) cause tuberculosis (TB). Infection is transmitted within and between livestock and wildlife populations, thus hampering TB control. Indirect transmission might be facilitated if MTC bacteria persist in the environment long enough to represent a risk of exposure to different species sharing the same habitat. We have, for the first time, addressed the relationship between environmental MTC persistence and the use of water resources in two TB endemic areas in southern Spain with the objective of identifying the presence of environmental MTC and its driving factors at ungulates' water aggregation points. Camera-trap monitoring and MTC diagnosis (using a new MTC complex-specific PCR technique) were carried out at watering sites. Overall, 55.8% of the water points tested positive for MTC in mud samples on the shore, while 8.9% of them were positive in the case of water samples. A higher percentage of MTC-positive samples was found at those waterholes where cachectic animals were identified using camera-trap monitoring, and at the smallest waterholes. Our results help to understand the role of indirect routes of cross-species TB transmission and highlight the importance of certain environmental features in maintaining infection in multihost systems. This will help to better target actions and implement control strategies for TB at the wildlife/livestock interface.

DNA Detection Reveals Mycobacterium tuberculosis Complex Shedding Routes in Its Wildlife Reservoir the Eurasian Wild Boar

Since the intensity and frequency of pathogen shedding by hosts determine the probability of infection through direct and indirect contact, the shedding characterization of Mycobacterium tuberculosis complex (MTC) in the key host reservoir in Iberia, the Eurasian wild boar (Sus scrofa), is crucial. We aimed (i) to describe the natural shedding routes of MTC in free-ranging wild boar by a new semi-automated PCR method and (ii) to determine the association of MTC shedding pattern with tuberculosis (TB) progression and individual factors. MTC shedding (by any of the possible routes) was detected in a total of 30.8% (±7.5) out of the sampled individuals with valid or interpretable test results (n = 39). The proportion of TB-positive shedders according to the route was 13.6% (±7.5) for oral swabs, 4.5% (±4.5) for nasal swabs, 4.5% (±4.4) for faecal swabs and 13.6% (±7.5) for individuals being positive to all swabs concomitantly. The probability of shedding mycobacteria (by any route) statistically associated with TB generalization, and the TB score was significantly higher in individuals testing positive to at least one route compared to negatives. Overall, a diversity of shedding routes in wild boar is possible, and it is remarkable that for the first time, the faecal shedding is confirmed for naturally infected wild boar. Our results are consistent with the role wild boar plays for TB maintenance in host communities and environments in Iberia and confirm that it is an important source of mycobacteria infection by different routes. Finally, we evidenced the use of a new PCR technique to detect MTC DNA in excretions can be practical and defined the target routes for sampling wild boar shedding in future studies, such as interventions to control TB in wild boar that can be measured in terms of impact on mycobacteria excretion and transmission (i.e. vaccination).

Antagonistic effects of Bacillus subtilis subsp. subtilis and B. amyloliquefaciens against Macrophomina phaseolina: SEM study of fungal changes and UV-MALDI-TOF MS analysis of their bioactive compounds

The antifungal effect of Bacillus subtilis subsp. subtilis PGPMori7 and Bacillus amyloliquefaciens PGPBacCA1 was evaluated against Macrophomina phaseolina (Tassi) Goid. Cell suspension (CS), cell-free supernatant (CFS) and the lipopeptide fraction (LF) of PGPMori7 and PGPBacCA1 were screened against three different M. phaseolina strains. CS exhibited the highest inhibitory effect (around 50%) when compared to those of CFS and LF, regardless of the fungal strain studied. The synthesis of lipopeptides was studied by UV-MALDI TOF. Chemical analysis of Bacillus metabolite synthesis revealed that surfactin and iturin were mainly produced in liquid medium. Potential fengycin was also co-produced when both Bacillus were cultivated in solid medium. In co-culture assays, the bacterial colony-fungal mycelium interface at the inhibition zone was evaluated by both scanning electron microscopy (SEM) and UV-MALDI TOF, the former to determine the structural changes on M. phaseolina cells and the latter to identify the main bioactive molecules involved in the inhibitory effect. PGPBacCA1 produced surfactin, iturin and fengycin in the inhibition zone while PGPMori7 only produced these metabolites within its colony and not in the narrow inhibition zone. Interestingly, SEM revealed that PGPBacCA1 induced damage in M. phaseolina sclerotia, generating a fungicidal effect as no growth was observed when normal growth conditions were reestablished. In turn, PGPMori7 inhibited the growth of the Macrophomina mycelium without fungal injury, resulting only in a fungistatic activity. From these results, it was determined that the two bacilli significantly inhibited the growth of an important phytopathogenic fungus by at least two different mechanisms: lipopeptide synthesis and competition among microorganisms.

Influence of age on IgE response in peanut-allergic children and adolescents from the Mediterranean area

BACKGROUND

Peanut allergens are common triggers of food allergy. Analyses of sensitization patterns, relationships with other allergens, clinical symptoms, and variation with age are needed. We studied sensitization to Ara h 2, Ara h 9, and Pru p 3 in a peanut allergic children/adolescents and the relationship with peach and pollen.

METHODS

Peanut allergic patients aged between 1 and 20 years old were classified into two groups: A) allergic to peanut only and B) allergic to peach and peanut. The IgE response was measured to Ara h 2, Ara h 9, and Pru p 3.

RESULTS

Of 964 subjects evaluated, 28% were allergic to peanut. From this group, 68% were also sensitized to pollen. Urticaria was the most frequent entity followed by anaphylaxis and OAS. Fifty-eight percent had Ara h 2- and/or Ara h 9-specific IgE. More than half reported symptoms with peanut alone (Group A) and 35% to peanut and peach (Group B). We observed significant differences in sex, age, onset of symptoms, and sensitization to Artemisia between groups. IgE response to Ara h 2 was more frequent in Group A, and Ara h 9 and Pru p 3 in Group B. We observed a decrease in sensitization to Ara h 2 and an increase to Ara h 9 and Pru p 3 with increasing age.

CONCLUSION

Peanut allergy is frequent in subjects with allergy to plant foods, with Ara h 2 and Ara h 9 being two important allergens. In younger patients, Ara h 2 predominates over Ara h 9. The reverse was observed in older patients.

Poor nutritional status is associated with a higher risk of falling and fracture in elderly people living at home in France: the Three-City cohort study

Falling and fractures are a public health problem in elderly people. The aim of our study was to investigate whether nutritional status is associated with the risk of falling or fracture in community-dwelling elderly. Poor nutritional status was significantly associated with a higher risk of both falling and fractures.

INTRODUCTION

Nutrition could play a role to prevent falls and fractures. The purpose of this study is to investigate whether a poor nutritional status is associated with the risk of falling and of fracture in community dwelling elderly.

METHODS

Baseline nutritional status of participants was assessed using the Mini Nutritional Assessment (MNA). After a follow-up of 12 years, 6040 individuals with available data for falls and 6839 for fracture were included. People who presented the outcomes at baseline were excluded. Cox models were used to evaluate the associations between nutritional status and the risks of fall or fracture.

RESULTS

The frequency of poor nutritional status (MNA ≤ 23.5), at baseline, was respectively 12.0% in the "fall study sample" and 12.8% in the "fracture study sample." Incident fall and fracture over 12 years were reported in 55.8 and 18.5% of the respective samples, respectively. In multivariate models controlled for sociodemographic data and several baseline health indicators, poor nutritional status was significantly associated with a higher risk of falling (hazard ratio (HR) = 1.66, 95% confidence interval (95% CI) 1.35-2.04 in men and HR = 1.20, 95% CI 1.07-1.34 in women) and with a higher risk of fracture (HR = 1.28, 95% CI 1.09-1.49).

CONCLUSION

Poor nutritional status was associated with a higher risk of both falling and fractures in French elderly community-dwellers. Early screening and management of the nutritional status may be useful to reduce the frequency of these events in older people.

A non-synonymous polymorphism in galectin-3 lectin domain is associated with allergic reactions to beta-lactam antibiotics

Genetic predictors of beta-lactam (BL) allergy are mostly related to Immunoglobulin E (IgE) synthesis and atopy. Despite this context, little attention has been devoted to genes of IgE/FcɛRI pathway, such as galectin-3, a β-galactoside-binding lectin, which binds to IgE. We evaluated the association of LGALS3 polymorphisms with BL allergy in 395 Spanish and 198 Italian cases, compared with 310- and 339-matched controls, respectively. The rs11125 predicted BL allergy with an odds ratio of 4.0 in Spanish population (P<0.0001). This association was replicated with an odds ratio of 5.1 in Italian population (P<0.0001); rs11125 predicted also increased serum level of total IgE in Spanish controls. These data are consistent with the predicted deleterious influence of Gln>His substitution produced by rs11125 on galactose-binding activity of galectin-3. In conclusion, LGALS3 is the strongest genetic predictor of BL allergy reported so far. This association reflects the influence of genes of IgE/FcɛRI pathway in this pathology.

Bacillus subtilis subsp. subtilis CBMDC3f with antimicrobial activity against Gram-positive foodborne pathogenic bacteria: UV-MALDI-TOF MS analysis of its bioactive compounds

In this work a new Bacillus sp. strain, isolated from honey, was characterized phylogenetically. Its antibacterial activity against three relevant foodborne pathogenic bacteria was studied; the main bioactive metabolites were analyzed using ultraviolet matrix assisted laser desorption-ionization mass spectrometry (UV-MALDI MS). Bacillus CBMDC3f was phylogenetically characterized as Bacillus subtilis subsp. subtilis after rRNA analysis of the 16S subunit and the gyrA gene (access codes Genbank JX120508 and JX120516, respectively). Its antibacterial potential was evaluated against Listeria monocytogenes (9 strains), B. cereus (3 strains) and Staphylococcus aureus ATCC29213. Its cell suspension and cell-free supernatant (CFS) exerted significant anti-Listeria and anti-S. aureus activities, while the lipopeptides fraction (LF) also showed anti-B. cereus effect. The UV-MALDI-MS analysis revealed surfactin, iturin and fengycin in the CFS, whereas surfactin predominated in the LF. The CFS from CBMDC3f contained surfactin, iturin and fengycin with four, two and four homologues per family, respectively, whereas four surfactin, one iturin and one fengycin homologues were identified in the LF. For some surfactin homologues, their UV-MALDI-TOF/TOF (MS/MS; Laser Induced Decomposition method, LID) spectra were also obtained. Mass spectrometry analysis contributed with relevant information about the type of lipopeptides that Bacillus strains can synthesize. From our results, surfactin would be the main metabolite responsible for the antibacterial effect.

Abstract W P143: Ankle-brachial Index Predicts Extracranial Vascular Events After Transient Ischemic Attacks. Data From The Promapa Study

The ankle brachial index (ABI) is a known measure of lower-limb peripheral artery disease (PAD), as well as an independent predictor of vascular events. Various methods of ABI calculation have been described. The traditional method (ABI-TM) uses the higher ankle pressure as a numerator and it results in higher specificity. The alternative method (ABI-AM) takes the lower ankle pressure as numerator. It is associated with better sensitivity. Our goal was to compare the prognostic value of abnormal ABI (ABI <=0.9), determined by the two methods, in order to predict subsequent stroke and extracranial vascular events (EVE) in transient ischemic attack (TIA) patients from a multicenter study.

Methods: We analyzed data from consecutive 1137 patients with TIA from the multicenter PROMAPA study in which ABI was determined. We determined risk of stroke recurrence (SR) and EVE (ischemic cardiopathy or peripheral arterial disease) at one year of follow up.

Results: A total of 616 (54.2%) subjects fulfilled all inclusion criteria. The risk of SR and EVE was 4.7% and 2.1%, respectively. The proportion of abnormal ABI differed according to the method used: 11.5% ABI-TM versus 38.0 ABI-AM (p=0.001). In both situations, abnormal ABI was related to the association of >1 risk factors and large artery atherosclerosis. SR was not predicted by abnormal ABI. However, only abnormal ABI-AM was significantly associated with EVE (p=0.003). Cox proportional-hazards multivariate analyses identify the association of > 1 risk factors (Hazard Ratio [HR] 4.7, 95% CI 1.1-21.2. p=0.045) and abnormal ABI-AM (HR 4.0, 95% CI 1.1-14.6, p=0.035) as independent predictors of EVE.

Conclusion: ABI using the lower ankle pressure as numerator is associated with EVE after TIA. The measurement of ABI using the lower ankle pressure as numerator among TIA patients appeared to be useful to identify patients with risk of EVE and to plan adequate prevention therapies or specific diagnostic protocols.

Hypersensitivity Reactions to Nonsteroidal Anti-inflammatory Drugs in Children and Adolescents: Selective Reactions

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used throughout the world to treat pain and inflammation; however, they can trigger several types of drug hypersensitivity reactions (DHRs) in all age groups. Although most such reactions occur through activation of the leukotriene pathway without specific immunological recognition (cross-intolerance), a significant number of DHRs to NSAIDs are due to immunological mechanisms (selective reactions [SRs]). SRs are thought to be induced by specific IgE antibodies or by T cells. In this manuscript, we focus on SRs, which are of great concern in children and adolescents and comprise a heterogeneous set of clinical pictures ranging from mild entities such as urticaria/angioedema to potentially life-threatening conditions such as Stevens-Johnson syndrome/toxic epidermal necrolysis. Paracetamol and ibuprofen are the most frequent elicitors of IgE-mediated SRs, although pyrazolones have also been implicated. T cell-mediated reactions are infrequent in children but have been associated with ibuprofen, naproxen, and dipyrone. In this review, we analyze the available literature on SRs in children and adolescents, with emphasis on epidemiological data, mechanisms, and drugs involved, as well as on diagnostic procedures.

Hypersensitivity reactions to β-lactams: relevance of hapten-protein conjugates

β-Lactams (BL) are the drugs most frequently involved in allergic reactions. They are classified according to their chemical structure as penicillins, cephalosporins, monobactams, carbapenems, and clavams. All BL antibiotics have a BL ring that is fused to a 5-member or 6-member ring (except in monobactams) and has 1, 2 or 3 side chains (except in clavams). Differences in chemical structure mean that a wide range of BLs are recognized by the immune system, and patients may experience clinical reactions to one BL while tolerating others. Diagnosis is based on skin and in vitro testing, although both display low sensitivity, possibly because they are based on drugs or drug conjugates that are not optimally recognized by the immune system. BLs are haptens that need to bind to proteins covalently to elicit an immune response. These drugs have a high capacity to form covalent adducts with proteins through nucleophilic attack of amino groups in proteins on the BL ring. Allergenic determinants have been described for all BLs, although benzylpenicillin is the most widely studied. Moreover, formation of BL-protein adducts is selective, as we recently demonstrated for amoxicillin, which mainly modifies albumin, transferrin, and immunoglobulin heavy and light chains in human serum. Given the complexity of BL allergy, understanding the immunological mechanisms involved and optimization of diagnostic methods require multidisciplinary approaches that take into account the chemical structures of the drugs and the carrier molecules, as well as the patient immune response.

Tolerance to COX-2 inhibitors in children with hypersensitivity to nonsteroidal anti-inflammatory drugs

BACKGROUND

Hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) can affect children, with the mechanism proposed being inhibition of the cyclooxygenase enzyme-1 (COX-1). In these patients nonchemically related NSAIDs, including COX-2 inhibitors, can induce the reaction, hampering treatment of fever and inflammatory processes.

OBJECTIVES

To analyse retrospectively tolerance to etoricoxib, a selective COX-2 inhibitor, and to meloxicam, a preferential COX-2 inhibitor, in children with hypersensitivity to NSAIDs.

METHODS

Clinical records of children (aged 1-14 years) diagnosed with hypersensitivity reactions to NSAIDs from January 2006 to January 2013 were included. The diagnosis was confirmed by oral drug provocation test (DPT) with the culprit NSAIDs and acetylsalicylic acid (ASA). Tolerance to paracetamol, etoricoxib and meloxicam was also evaluated.

RESULTS

The study included 41 children with a positive DPT with ASA and the culprit NSAID. DPT with paracetamol and etoricoxib was negative in all children, although two (4.9%) children developed a reaction after the administration of meloxicam.

CONCLUSIONS

These data indicate that both etoricoxib and meloxicam are good alternatives for treatment in older children with hypersensitivity to NSAIDs.