How predictors and patterns of stroke recurrence after a TIA differ during the first year of follow-up

The highest risk of subsequent stroke after a TIA occurs within the first week after the index event. However, the risk of stroke recurrence (SR) remains high during the first year of follow-up. We studied the temporal pattern and predictors of SR (at 7 days and from 7 days to 1-year follow-up). Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We determined the short-term (at 7 days) and long-term (from 8 days to 1 year) risk of SR. Patients who underwent short-term recurrence and long-term recurrence were compared with regard to clinical findings, vascular territories, and etiology. Enough information (clinical variables and extracranial vascular imaging) was assessed in 1,137 (90.6 %) patients. The 7-day stroke risk was 2.6 %. 32 (3.0 %) patients had an SR after 7-day follow-up. Multiple TIA (HR 3.50, 1.67-7.35, p = 0.001) and large artery atherosclerosis (HR 2.51, 1.17-5.37, p = 0.018) were independent predictors of early SR, whereas previous stroke (HR 1.40, 1.03-1.92, p = 0.034) and coronary heart disease (2.65, 1.28-5.50, p = 0.009) were independent predictors of late SR. Notoriously, 80 % of SR happened in the same territory of the index TIA at 7-day follow-up, whereas only 38 % during the long-term follow-up (p < 0.001). Different predictors of SR were identified throughout the follow-up period. Moreover, the ischemic mechanism differed in early and late stroke recurrences.

Advanced phenotyping in hypersensitivity drug reactions to NSAIDs

Non-steroidal anti-inflammatory drugs (NSAIDs) are the medications most frequently involved in hypersensitivity drug reactions. Because NSAIDs are prescribed for many conditions, this is a world-wide problem affecting patients of all ages. Various hypersensitivity reactions have been reported, mainly affecting the skin and/or the respiratory airways. The most frequent of these is acute urticaria, which can be induced by several different NSAIDs. Both specific and non-specific immunological pathways have been proposed as underlying mechanisms. This review presents the clinical phenotypes and the drugs involved in NSAID hypersensitivity. Five major clinical syndromes can be distinguished: aspirin-exacerbated respiratory disease (AERD), aspirin-exacerbated cutaneous disease (AECD), multiple NSAID-induced urticaria/angioedema (MNSAID-UA), single NSAID-IgE reactions and single NSAID T cell responses. However, further classification is possible within these five major entities, by detailed descriptions of the clinical characteristics enabling more phenotypes to be defined. This detailed differentiation now seems required in order to undertake appropriate pharmacogenetic studies.

Diagnostic evaluation of hypersensitivity reactions to beta-lactam antibiotics in a large population of children

INTRODUCTION

Hypersensitivity reactions to beta-lactams (BLs) are often reported in children, with amoxicillin and, to a lesser extent, cephalosporins being the most frequent drugs involved. Although many of these children are considered to be allergic, a careful evaluation only confirms a low percentage.

OBJECTIVES

To analyse the clinical data, sensitization profile and diagnostic methods used in a large group of children with a clinical history of hypersensitivity reactions to BLs.

METHODS

The study included children aged 1-14 yr with symptoms suggestive of hypersensitivity to BLs from January 2006-December 2012. Diagnosis was confirmed from a clinical history, specific IgE determination, skin testing and, if necessary, a drug provocation test (DPT).

RESULTS

Of a total of 783 patients studied, only 62 (7.92%) were confirmed as being allergic, 9 (14.52%) with immediate and 53 (85.48%) with non-immediate reactions. In those with immediate reactions, 2 (22.22%) were diagnosed by in vitro test, 2 (22.22%) by skin testing and 5 (55.56%) by DPT; in those with non-immediate reactions, 2 (3.77%) were diagnosed by skin testing and 51 (96.23%) by DPT. In all cases, DPT was positive to the culprit drug (29 AX-CLV, 26 AX, 1 cefixime and 1 cefaclor), and the most usual symptoms were exanthema in 43 cases, urticaria in 12, urticaria-angio-oedema in 1 and erythema in 1 case.

CONCLUSION

After an allergological work-up, over 90% of the children evaluated were finally confirmed as tolerant to BLs. Most reactions were of the non-immediate type, and DPT was an essential tool for diagnosis.

Trends in hypersensitivity drug reactions: more drugs, more response patterns, more heterogeneity

Hypersensitivity drug reactions (HDRs) vary over time in frequency, drugs involved, and clinical entities. Specific reactions are mediated by IgE, other antibody isotypes (IgG or IgM), and T cells. Nonspecific HDRs include those caused by nonsteroidal anti-inflammatory drugs (NSAIDs). beta-Lactams--the most important of which are amoxicillin and clavulanic acid--are involved in specific immunological mechanisms. Fluoroquinolones (mainly moxifloxacin, followed by ciprofloxacin and levofloxacin) can also induce HDRs mediated by IgE and T cells. In the case of radio contrast media, immediate reactions have decreased, while nonimmediate reactions, mediated by T cells, have increased. There has been a substantial rise in hypersensitivity reactions to antibiotics and latex in perioperative allergic reactions to anesthetics. NSAIDs are the most frequent drugs involved in HDRs. Five well-defined clinical entities, the most common of which is NSAID-induced urticaria/angioedema, have been proposed in a new consensus classification. Biological agents are proteins including antibodies that have been humanized in order to avoid adverse reactions. Reactions can be mediated by IgE or T cells or they may be due to an immunological imbalance. Chimeric antibodies are still in use and may have epitopes that are recognized by the immune system, resulting in allergic reactions.

Practical guidelines for diagnosing hypersensitivity reactions to nonsteroidal anti-inflammatory drugs

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the drugs most frequently involved in hypersensitivity reactions. These reactions include various clinical entities with different mechanisms leading to the release of inflammatory mediators. Characterization of patients based on clinical manifestations and suspected underlying mechanisms is critical for implementation of adequate diagnostic procedures and patient management. Our objectives were to prepare a systematic review of available scientific evidence and to provide general guidelines for the diagnosis and management of patients with hypersensitivity reactions to NSAIDs. We also propose a practical algorithm for the diagnosis of specific types of hypersensitivity to NSAIDs and provide recommendations for the management of hypersensitive patients.

HPLC separation of human serum albumin isoforms based on their isoelectric points

Human serum albumin (HSA) is the most abundant protein in plasma. Cys34, the only free Cys residue, is the predominant plasma thiol and a relevant sacrificial antioxidant. Both in vivo circulating HSA and pharmaceutical preparations are heterogeneous with respect to the oxidation state of Cys34. In this work, we developed an external pH gradient chromatofocusing procedure that allows the analysis of the oxidation status of HSA in human plasma and biopharmaceutical products based on the different apparent isoelectric points and chemical properties of the redox isoforms. Specifically, reduced-mercury blocked HSA (HSA-SHg(+)), HSA with Cys34 oxidized to sulfenic acid (HSA-SOH) and HSA oxidized to sulfinate anion (HSA-SO2(-)) can be separated with resolutions of 1.4 and 3.1 (first and last pair) and hence quantified and purified. In addition, an N-terminally degraded isoform (HSA3-585) in different redox states can be resolved as well. Confirmation of the identity of the chromatofocusing isolated isoforms was achieved by high resolution whole protein MS. It is proposed that the chromatofocusing procedure can be used to produce more exact and complete descriptions of the redox status of HSA in vivo and in vitro. Finally, the scalability capabilities of the chromatofocusing procedure allow for the preparation of highly pure standards of several redox isoforms of HSA.

Genome-wide association study in NSAID-induced acute urticaria/angioedema in Spanish and Han Chinese populations

AIM

Acute urticaria/angioedema (AUA) induced by cross-intolerance to NSAIDs is the most frequent clinical entity in hypersensitivity reactions to drugs. In this work, we conducted a genome-wide association study in Spanish and Han Chinese patients suffering from NSAID-induced AUA.

MATERIALS & METHODS

A whole-genome scan was performed on a total of 232 cases (112 Spanish and 120 Han Chinese) with NSAID-induced AUA and 225 unrelated controls (124 Spanish and 101 Han Chinese).

RESULTS

Although no polymorphism reached genome-wide significance, we obtained suggestive associations for three clusters in the Spanish group (RIMS1, BICC1 and RAD51L 1) and one region in the Han Chinese population (ABI3BP). Five regions showed suggestive associations after meta-analysis: HLF, RAD51L1, COL24A1, GalNAc-T13 and FBXL7. A majority of these genes are related to Ca(2+), cAMP and/or P53 signaling pathways.

CONCLUSION

The associations described were different from those related to the metabolism of arachidonic acid and could provide new mechanisms underlying NSAID-induced AUA.

Variability in histamine receptor genes HRH1, HRH2 and HRH4 in patients with hypersensitivity to NSAIDs

Aim: Histamine plays an important role in the pathogenesis of allergic diseases. Genetic variations in histamine receptors (HRH) may influence the expression of allergic diseases. This study analyzes the association between HRH variants and NSAID hypersensitivity reactions. Patients & methods: The authors analyzed copy number variations (CNVs) and common functional SNPs in genes HRH1, HRH2 and HRH4 in 442 unrelated patients with hypersensitivity to NSAIDs and in 414 healthy unrelated controls. Results: The authors identified, both in patients and control subjects, individuals carrying CNVs in HRH genes. The most common genotype corresponded to two copies of each gene, but carriers of one or three copies of HRH1 (5% of individuals), HRH2 (1.1%) and HRH4 genes (0.9%) were also identified. Conclusion: For the first time, we describe CNVs in human HRH genes. Neither common functional SNPs in HRH genes nor CNVs influenced the risk of developing hypersensitivity to NSAIDs.

Original submitted 31 May 2013; Revision submitted 7 August 2013

Value of the clinical history in the diagnosis of urticaria/angioedema induced by NSAIDs with cross-intolerance

BACKGROUND

Multiple Non-steroidal anti-inflammatory drugs (NSAID)-induced urticaria/angioedema is the most common manifestation of hypersensitivity reactions to NSAIDs. Diagnostic evaluation is based on the clinical history and a drug provocation test.

OBJECTIVE

To evaluate the role of the clinical history in the diagnosis of multiple NSAID-induced urticaria/angioedema.

METHODS

We studied a group of patients with an unequivocal history of urticaria and/or angioedema after NSAID intake. Subjects had to have had at least two episodes of cutaneous symptoms with two different COX-1 inhibitors. The diagnosis was confirmed in all cases by a drug provocation test with acetyl salicylic acid (ASA). Multivariate analysis was done by analysing different variables, including number of drugs involved, episodes and time elapsed between drug intake and symptom onset.

RESULTS

Of the total group of 75 cases with multiple NSAID-induced urticaria/angioedema diagnosed according to the clinical history, 76% developed a positive drug provocation test with ASA. The risk for having hypersensitivity was 17 times higher in patients who developed symptoms within the first 60 min after drug intake, 13 times higher in those who experienced reactions with more than two non-chemically related NSAIDs, and 10 times higher in women.

CONCLUSIONS

Drug provocation testing with ASA confirms the diagnosis of multiple NSAID-induced urticaria/angioedema in up to 92% of cases with an unequivocal clinical history, when reactions occur within 1 h and more than two different NSAIDs are involved.

Food allergy: management, diagnosis and treatment strategies

Food allergy is an increasing problem in western countries, with strict avoidance being the only available reliable treatment. However, accidental ingestion can occur and anaphylactic reactions still happen. In recent years, many efforts have been made to better understand the humoral and cellular mechanisms involved in food allergy, and to improve the strategies for diagnosis and treatment. This review focuses on IgE-mediated food hypersensitivity and provides an overview of the diagnostic strategies and treatment advances. Specific immunotherapy, including different routes of administration and allergen sources, such as natural, recombinant and T-cell epitopes, are analyzed in detail. Other treatments such as anti-IgE monoclonal antibody therapy, adjuvant therapy and Chinese herbs will also be described.

Recurrent transient ischaemic attack and early risk of stroke: data from the PROMAPA study

BACKGROUND

Many guidelines recommend urgent intervention for patients with two or more transient ischaemic attacks (TIAs) within 7 days (multiple TIAs) to reduce the early risk of stroke.

OBJECTIVE

To determine whether all patients with multiple TIAs have the same high early risk of stroke.

METHODS

Between April 2008 and December 2009, we included 1255 consecutive patients with a TIA from 30 Spanish stroke centres (PROMAPA study). We prospectively recorded clinical characteristics. We also determined the short-term risk of stroke (at 7 and 90 days). Aetiology was categorised using the TOAST (Trial of Org 10172 in Acute Stroke Treatment) classification.

RESULTS

Clinical variables and extracranial vascular imaging were available and assessed in 1137/1255 (90.6%) patients. 7-Day and 90-day stroke risk were 2.6% and 3.8%, respectively. Large-artery atherosclerosis (LAA) was confirmed in 190 (16.7%) patients. Multiple TIAs were seen in 274 (24.1%) patients. Duration <1 h (OR=2.97, 95% CI 2.20 to 4.01, p<0.001), LAA (OR=1.92, 95% CI 1.35 to 2.72, p<0.001) and motor weakness (OR=1.37, 95% CI 1.03 to 1.81, p=0.031) were independent predictors of multiple TIAs. The subsequent risk of stroke in these patients at 7 and 90 days was significantly higher than the risk after a single TIA (5.9% vs 1.5%, p<0.001 and 6.8% vs 3.0%, respectively). In the logistic regression model, among patients with multiple TIAs, no variables remained as independent predictors of stroke recurrence.

CONCLUSIONS

According to our results, multiple TIAs within 7 days are associated with a greater subsequent risk of stroke than after a single TIA. Nevertheless, we found no independent predictor of stroke recurrence among these patients.

Biochemical characterization of VQ-VII, a cysteine peptidase with broad specificity, isolated from Vasconcellea quercifolia latex

The latex from Vasconcellea quercifolia ("oak leaved papaya"), a member of the Caricaceae family, contains at least seven cysteine endopeptidases with high proteolytic activity, which helps to protect these plants against injury. In this study, we isolated and characterized the most basic of these cysteine endopeptidases, named VQ-VII. This new purified enzyme was homogeneous by bidimensional electrophoresis and MALDI-TOF mass spectrometry, and exhibited a molecular mass of 23,984 Da and an isoelectric point >11. The enzymatic activity of VQ-VII was completely inhibited by E-64 and iodoacetic acid, confirming that it belongs to the catalytic group of cysteine endopeptidases. By investigating the cleavage of the oxidized insulin B-chain to establish the hydrolytic specificity of VQ-VII, we found 13 cleavage sites on the substrate, revealing that it is a broad-specificity peptidase. The pH profiles toward p-Glu-Phe-Leu-p-nitroanilide (PFLNA) and casein showed that the optimum pH is about 6.8 for both substrates, and that in casein, it is active over a wide pH range (activity higher than 80 % between pH 6 and 9.5). Kinetic enzymatic assays were performed with the thiol peptidase substrate PFLNA (K m = 0.454 ± 0.046 mM, k cat = 1.57 ± 0.07 s(-1), k cat/K m = 3.46 × 10(3) ± 14 s(-1) M(-1)). The N-terminal sequence (21 amino acids) of VQ-VII showed an identity >70 % with 11 plant cysteine peptidases and the presence of highly conserved residues and motifs shared with the "papain-like" family of peptidases. VQ-VII proved to be a new latex enzyme of broad specificity, which can degrade extensively proteins of different nature in a wide pH range.

Genetic variants of the arachidonic acid pathway in non-steroidal anti-inflammatory drug-induced acute urticaria

BACKGROUND

To date, genetic studies of hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) have been carried out mainly in aspirin-induced asthma and to a lesser extent in chronic urticaria, with no studies in patients with acute urticaria (AU), the most common entity induced by these drugs.

OBJECTIVE

In this work, we analysed the association of common variants of 15 relevant genes encoding both enzymes and receptors from the arachidonic acid (AA) pathway with NSAID-induced AU.

METHODS

Patients were recruited in several Allergy Services that are integrated into the Spanish network RIRAAF, and diagnosed of AU induced by cross-intolerance (CRI) to NSAIDs. Genotyping was carried out by TaqMan allelic discrimination assays.

RESULTS

A total of 486 patients with AU induced by CRI to NSAIDs and 536 unrelated controls were included in this large Spanish case-control study. Seven variants from 31 tested in six genes were associated in a discovery study population from Malaga (0.0003 ≤ p-value ≤ 0.041). A follow-up analysis in an independent sample from Madrid replicated three of the SNPs from the ALOX15 (rs7220870), PTGDR (rs8004654) and CYSLTR1 (rs320095) genes (1.055x10(-6) ≤meta-analysis p-value ≤ 0.003).

CONCLUSIONS AND CLINICAL RELEVANCE

Genetic variants of the AA pathway may play an important role in NSAID-induced AU. These data may help understand the mechanism underlying this disease.

Predictive value of brain and vascular imaging including intracranial vessels in transient ischaemic attack patients: external validation of the ABCD3-I score

BACKGROUND AND PURPOSE

Recently, brain and vascular imaging have been added to clinical variables to identify patients with transient ischaemic attack (TIA) with a high risk of stroke recurrence. The aim of our study was to externally validate the ABCD3-I score and the same score taking into account intracranial circulation.

METHODS

We analyzed data from 1137 patients with TIA from the PROMAPA study who underwent diffusion-weighted magnetic resonance imaging (DWI) within 7 days of symptom onset. Clinical variables and diagnostic work-up were recorded prospectively. The end-points were subsequent stroke at 7 and 90 days follow-up.

RESULTS

A total of 463 (40.7%) subjects fulfilled all inclusion criteria. During follow-up, eight patients (1.7%) had a stroke within 7 days, and 14 (3.1%) had a stroke within 3 months. In the Cox proportional hazard multivariate analyses, the combination of large-artery atherosclerosis and positive DWI remained as independent predictors of stroke recurrence at 7- and 90-day follow-up [HR 8.23, 95% confidence interval (CI) 2.89-23.46, P < 0.001]. The ABCD3-I score was a powerful predictor of subsequent stroke. The area under the receiver operating characteristic curve was 0.83 (95% CI 0.72-0.93) at 7 days and 0.69 (95% CI 0.53-0.85) at 90 days. When we include intracranial vessel disease in the score, the area under the curve increases but the difference observed was non-significant.

CONCLUSION

The inclusion of vascular and neuroimaging information to clinical scales (ABCD3-I score) provides important prognostic information and also helps management decisions, although it cannot give a complete distinction between high-risk and low-risk groups.

In vitro methods for diagnosing nonimmediate hypersensitivity reactions to drugs

Nonimmediate drug hypersensitivity reactions (DHRs) are difficult to manage in daily clinical practice, mainly owing to their heterogeneous clinical manifestations and the lack of selective biological markers. In vitro methods are necessaryto establish a diagnosis, especially given the low sensitivity of skin tests and the inherent risks of drug provocation testing. In vitro evaluation of nonimmediate DHRs must include approaches that can be applied during the different phases of the reaction. During the acute phase, monitoring markers in both skin and peripheral blood helps to discriminate between immediate and nonimmediate DHRs with cutaneous responses and to distinguish between reactions that, although they present similar clinical symptoms, are produced by different immunological mechanisms and therefore have a different treatment and prognosis. During the resolution phase, in vitro testing is used to detect the response of T cells to drug stimulation; however, this approach has certain limitations, such as the lack of validated studies assessing sensitivity. Moreover, in vitro tests indicate an immune response that is not always related to a DHR. In this review, members of the Immunology and Drug Allergy Committee of the Spanish Society of Allergy and Clinical Immunology (SEAIC) provide an overview of the most widely used in vitro tests for evaluating nonimmediate DHRs.