Non-tuberculous mycobacteria: occurrence in skin test cattle reactors from official tuberculosis-free herds

Non-tuberculous mycobacteria (NTM) are considered a relevant cause of non-specific reactions to the most widely applied bovine tuberculosis (bTB) test, the intradermal tuberculin test. In order to establish which NTM species might act as a potential source of such diagnostic interference, a collection of 373 isolates obtained from skin test positive cows from 359 officially tuberculosis-free (OTF) herds, culled in the framework of the bTB eradication campaign in Spain, were identified at the species level through PCR and Sanger sequencing of the 16S rDNA, hsp65 and rpoB genes. Of the 308 isolates for which a reliable identification was achieved, 32 different mycobacterial species were identified, with certain species being most represented: among M. avium complex members (n = 142, 46.1%), M. avium subsp. hominissuis (98; 69.0%) was the most abundant followed by M. avium subsp. avium (33, 23.2%), and M. intracellulare (7, 4.9%). Among non-MAC members (n = 166, 53.9%), M. nonchromogenicum (85; 27.6%) and M. bourgelatii (11; 5.6%) were the predominant species. In addition, mixed results were obtained in 53 isolates presenting up to 30 different genotypes, which could be indicative of new mycobacterial species. Our results represent a first step toward characterizing the diversity of NTM species that could interfere with official diagnostic tests for bTB eradication in Spain.

Pilot study on the use of basophil activation tests and skin tests for the prevention of allergic transfusion reactions

Background and objectives

Management of severe allergic transfusion reactions (ATR) is challenging. In this study, we investigate the usefulness of skin tests and basophil activation tests (BAT) in chronically transfused patients for the prevention of future ATR.

Materials and methods

BAT and skin tests were carried with the supernatant of red blood cell (RBC) units for a sickle-cell disease patient under chronic exchange transfusion who has presented a severe ATR, in order to prevent potential future ATR. If the results for both BAT and skin tests were negative, the RBC units could be transfused to the patient. If either one of the results was positive, the tested RBC unit was discarded for the patient.

Results

192 RBC units were tested with both tests. The level of results concordance between the two tests was 95%. Out of the 169 negative units with both tests, 118 units were transfused to the patient for which he presented no ATR.

Conclusion

In our study, combining both BAT and skin tests was associated with a good negative predictive value since we were able to safely transfuse our patient. Further studies are still necessary to confirm this result but this pilot study indicates that skin tests and BAT might help prevent ATR. When BAT is not available, skin tests may also be useful in preventing ATR.

Drug reaction with eosinophilia and systemic symptoms in a paediatric population: Interest of skin tests

BACKGROUND

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe adverse drug reaction. It is uncommon in the paediatric population and can be difficult to diagnose as its initial symptoms may mimic a viral infection.

OBJECTIVE

To analyse the features of paediatric DRESS and to evaluate the interest of skin tests in identifying the causative drugs.

METHODS

It is a retrospective analysis (2004-2021) of DRESS cases diagnosed in paediatric patients. The DRESS diagnosis was defined using the RegiSCAR scoring. The skin tests were performed according to the ENDA recommendations.

RESULTS

We included 19 cases of DRESS occurred in 18 patients. Common clinical symptoms were exanthema and fever in 94.7% of cases each. The most commonly affected organ was the liver (84.2%). Among the implicated drugs, 16 were tested and skin tests were positive in 75%. To assess cross-reactivity and co-sensitization, skin tests with related and/or co-administered drugs were performed in eight patients. Among them, only one child had positive results.

CONCLUSION

Early diagnosis of DRESS and discontinuation of the incriminated drug might reduce the incidence of mortality in the paediatric population. Skin tests could be a safe and useful tool to identify the causative drug and assess cross-reactivity.

Delayed hypersensitivity reactions to iodinated contrast media: A diagnostic approach by skin tests

BACKGROUND

Adverse drug reactions to iodinated contrast media (ICM) have risen due to their increasing use in x-ray-based imaging modalities. Delayed hypersensitivity reactions are mainly caused by nonionic monomeric compounds and represent an issue impacting the diagnostic-therapeutic pathways of cancer, cardiology and surgery patients.

OBJECTIVES

To prospectively evaluate the usefulness of skin tests in delayed hypersensitivity reactions to ICM and to evaluate the tolerability of iobitridol, a monomeric nonionic low osmolality compound, as a possible safe alternative.

METHODS

Patients with delayed hypersensitivity reactions to ICM referred to us from 2020 to 2022 were prospectively enrolled in the study. All patients underwent patch test and, if negative, intradermal test with the culprit ICM and iobitridol as alternative.

RESULTS

A total of 37 patients (females 24, 64.9%) were enrolled in the study. Iodixanol and iomeprol were the most frequently involved ICM (48.5% and 35.2%, respectively); 62.2% of patients presented maculopapular eruption, while 37.8% reported delayed urticaria-like rash. Skin tests resulted positive to the culprit ICM in 19 patients (51.4%), 16 to patch test and 3 to intradermal test. Skin tests with iobitridol, tested as alternative, resulted positive in 3/19 patients (15.8%). All 16 patients with negative results to iobitridol were administered this ICM and tolerated it.

CONCLUSIONS

In at least half of patients, delayed-type hypersensitivity was demonstrated by skin tests, particularly by patch test. This diagnostic approach resulted simple, cost-effective and safe, not only to confirm the culprit ICM but also to identify iobitridol as feasible alternative.

Laboratory Investigations in Infectious Uveitis

Laboratory investigations can play a significant role in the diagnosis and decision-making of infectious uveitis. Though direct demonstration of the infective organism remains the gold standard of diagnosis, it is not always possible with ocular tissues. Recent advancements in molecular techniques have made it possible to overcome these limitations and to identify the genomic DNA of pathogens associated with infectious uveitis. Techniques such as next-generation sequencing can analyze all DNA-based lifeforms, regardless of whether they are bacteria, fungi, viruses, or parasites and have been used in the laboratory diagnosis of intraocular inflammation. On the other hand, serological tests, though they dominate the diagnostic landscape of various infectious etiologies in uveitis in routine clinical practice, have varied specificities and sensitivities in different infectious uveitis. In this review, we focus on various methods of laboratory diagnosis of infectious uveitis and discuss the recent advances in molecular diagnosis and their role in various infectious clinical entities.

Pulmonary Tuberculosis in Children: A Forgotten Disease?

Even today, tuberculosis in childhood is a disease that is often undiagnosed and undertreated. In the absence of therapy with antituberculosis drugs, children in the first years of life have a high degree of severe forms and mortality. In these children, symptoms are often not very specific and can easily be confused with other diseases of bacterial, viral or fungal etiology, making diagnosis more difficult. Nevertheless, the introduction of new diagnostic techniques has allowed a more rapid identification of the infection. Indeed, Interferon gamma release assay (IGRA) is preferred to the Mantoux, albeit with obvious limitations in children aged <2 years. While the Xpert Mtb/RIF Ultra test is recommended as an initial diagnostic investigation of the gastric aspirate and/or stools in children with signs and symptoms of pulmonary tuberculosis. The drugs used in the treatment of susceptible and resistant TB are the same as those used in adults but doses and combinations are different in the pediatric age. In children, brief therapy is preferable in both the latent infection and the active disease, as a significant reduction in side effects is obtained.

A Systematic Review on the Safety of Mycobacterium tuberculosis-Specific Antigen-Based Skin Tests for Tuberculosis Infection Compared With Tuberculin Skin Tests

Background

A systematic review showed that the accuracy of Mycobacterium tuberculosis antigen-based skin tests (TBSTs) for tuberculosis is similar to that of interferon γ release assay, but the safety of TBSTs has not been systematically reviewed.

Methods

We searched for studies reporting injection site reactions (ISRs) and systemic adverse events associated with TBSTs. We searched Medline, Embase, e-library, the Chinese Biomedical Literature Database, and the China National Knowledge Infrastructure database for studies through 30 July 2021, and the database search was updated until 22 November 2022.

Results

We identified 7 studies for Cy-Tb (Serum Institute of India), 7 (including 2 found through the updated search) for C-TST (Anhui Zhifei Longcom), and 11 for Diaskintest (Generium). The pooled risk of any injection site reactions (ISRs) due to Cy-Tb (n = 2931; 5 studies) did not differ significantly from that for tuberculin skin tests (TSTs; risk ratio, 1.05 [95% confidence interval, .70-1.58]). More than 95% of ISRs were reported as mild or moderate; common ISRs included pain, itching, and rash. In 1 randomized controlled study, 49 of 153 participants (37.6%) given Cy-Tb experience any systemic adverse event (eg, fever and headache), compared with 56 of 149 participants (37.6%) given TST (risk ratio, 0.85 [95% confidence interval, .6-1.2]). In a randomized controlled study in China (n = 14 579), the frequency of systemic adverse events in participants given C-TST was similar to that for TST, and the frequency of ISRs was similar to or lower than that for TST. Reporting of the safety data on Diaskintest was not standardized, precluding meta-analysis.

Conclusion

The safety profile of TBSTs appears similar to that of TSTs and is associated with mostly mild ISRs.

Polyethylene Glycol and Polysorbate 80 Skin Tests in the Context of an Allergic Risk Assessment for Hypersensitivity Reactions to Anti-SARS-CoV-2 mRNA Vaccines

Concern has arisen about hypersensitivity reactions in patients with allergic reactions to drugs containing polyethylene glycol (PEG) or polysorbate 80 (PS80), excipients of currently available anti-SARS-CoV-2 mRNA vaccines. However, the actual utility of PEG and PS80 skin allergy testing is currently still debated. We retrospectively analyzed all cases of patients on whom we performed allergometric skin tests for PEG and PS80 in the context of a pre-vaccination screening (for patients with multiple hypersensitivity reactions to drugs for which these excipients were among the suspected agents) or following suspected hypersensitivity reactions to anti-SARS-CoV-2 vaccines. A total of 134 tests were performed for PEG and PS80, eight of which produced uninterpretable results (due to dermographism or non-specific reactions). Of the remaining 126 cases (85 pre-vaccinal and 41 post-vaccine reactions), 16 (12.7%) were positive for PEG and/or PS80. Stratifying by clinical indication, there were no statistically significant differences in the proportion of positive tests between patients evaluated in the context of the pre-vaccination screening and those evaluated after a vaccine reaction (10.6% vs. 17.1%, respectively, p = 0.306). Allergometric skin tests for PEG and PS80 in our case series resulted positive in an unexpectedly high proportion of patients, suggesting that testing for allergy to these two excipients should not be ignored in case of reasonable clinical suspicion.

Beta-lactam hypersensitivity in children: Frequency and risk factors

AIMS

To determine the frequency of an authentic β-lactam (BL) hypersensitivity (HS) amongst a large number of children and to identify clinical risk factors that predict this hypersensitivity.

METHODS

All children with suspected BL allergy were evaluated by skin tests (ST) with the suspected BL. A 1-day oral provocation test (OPT) was performed in children with negative ST. We defined an authentic BL-HS case if the child exhibited a positive ST or a positive OPT. Risk factors associated with BL-HS were assessed using a univariate analysis. Covariates showing a P-value <.2 were included in the multivariate logistic regression analysis to determine independent predictors.

RESULTS

A total of 354 patients reporting 368 suspected BL reactions were included. The diagnosis of BL-HS was established in 24 children (6.7%). All these children had a positive ST. OPT was performed in 30 patients and was negative in all of them. In 110 children with a negative ST, BL was tolerated. In the risk factors analysis, 164 children were included. Older age (>5 years) at the reaction (odds ratio = 1.11; 95% confidence interval, 1.01-1.22; P = .02) and BL administered (odds ratio = 7.7; 95% confidence interval, 2.76-21.8; P < .001) were significantly associated with authentic BL-HS.

CONCLUSION

BL-HS should be evaluated with an appropriate allergy work-up before strict prohibition is made. In addition, age of patient and BL involved can be used as predictive factors of developing BL-HS in this population.

Drug allergy evaluation in children with suspected mild antibiotic allergy

Background

Adverse antibiotic reactions caused by an immunological mechanism are known as allergic reactions. The percentage of reported antibiotic allergies is likely to differ from the one validated after a drug provocation test (DPT) with the culprit antibiotic. This study aimed to compare the percentage of children who were thought to be allergic to a certain antibiotic with those who have a true allergy, as confirmed by DPTs. We also validated Skin Prick Tests (SPTs) and Intradermal Tests (IDTs) by assessing their sensitivity and specificity, in diagnosing antibiotic allergies using DPT as the gold standard. Furthermore, we investigated epidemiological risk factors such as personal and family history of atopic disease and eosinophilia.

Methods

Children with a history of possible allergic reaction to an antibiotic underwent a diagnostic procedure that included: (1) Eosinophil blood count, (2) SPTs, (3) IDTs and (4) DPTs. The parameters were compared with Pearson's Chi-Square and Fisher's Exact Test. Several risk factors that were found significant in univariate analysis, such as personal and family history of atopic disease, and positive SPTs and IDTs were examined with multiple logistic regression analysis to see if they were related to a higher risk for a positive DPT.

Results

Semi-synthetic penicillin was the most common group of antibiotics thought to cause allergic reactions in this study. Overall, 123 children with a personal history of an adverse reaction to a certain antibiotic, were evaluated. In 87.8% of the cases, the symptoms had occurred several hours after administration of the culprit antibiotic. Both SPTs and IDTs had low sensitivity but high specificity. Moreover, they had a high positive predictive value (PPV). In contrast, eosinophilia was not recognized as a risk factor. Seventeen patients (13.8%) had a true antibiotic allergy, as confirmed by a positive DPT. A positive IDT was a strong predictor of a positive DPT, along with a positive personal and family history of atopy.

Conclusion

SPTs and IDTs are very reliable in confirming antibiotic allergy when found positive. A negative result of a SPT highly predicts a negative DPT. A positive IDT and a positive personal and family history of atopy were recognized as significant risk factors for antibiotic allergy.

Immediate hypersensitivity reactions to iodinated contrast media: The diagnosis of allergy by skin testing

Among 74 patients with an immediate hypersensitivity reaction (IHR) to iodinated contrast media (ICM), the rate of allergic patients confirmed by positive prick test or diluted intradermal test (IDT) was 8.1%. 12.5% of re-exposed patients had a recurrent IHR despite negative skin tests. Investigations on pure IDT to ICM and development of drug provocation test may provide additional safety nets to uncover recurrent ICM reactors. Agreements among allergists are needed to unify practices.

Current practices in delaying testing for IgE-mediated food allergy after anaphylaxis

Background

General recommendations for delaying allergy testing, especially skin testing, in the weeks following anaphylaxis have been proposed owing to concern for false-negative results. However, no specific guidelines exist to aid clinicians in the decision regarding when to perform postanaphylactic food allergy testing and which test to use. The current practices of allergists regarding a delay in testing for food allergy after anaphylaxis are unknown.

Objective

We aimed to quantify the use of different approaches to postanaphylactic food allergy testing among allergists across the United States.

Methods

A clinical scenario was presented to 82 allergy and immunology fellowship program directors via e-mail survey. They were asked whether they avoid skin prick and/or blood-specific IgE testing in a child in the 6 weeks following suspected food-induced anaphylaxis owing to concern for false-negative results.

Results

The survey response rate was 33%. Of the 27 respondents, 4 (14.8%) avoid both blood and skin testing, 7 (25.9%) avoid skin testing only, and 16 (59.3%) do not avoid any testing.

Conclusion

Given the paucity of published evidence, a spectrum of opinions exists regarding testing in the weeks following food-induced anaphylaxis. About 40% of the allergy and immunology fellowship program directors in the United States who responded to the survey in this study avoid some allergy testing in the first 6 weeks after food-induced anaphylaxis owing to concern for false-negative results.

[Аllergic sensitization in children with atopic dermatitis in the first 2 years of life according to the results of skin tests]

Atopic dermatitis (AD) is associated with food allergies (FA), which frequency and structure varies from region. The objective of the research was to determine the structure of FA in children (<2 years) with AD and to analyze age-specific sensitization. Methods. 79 children with AD aged 2-24 months were examined (Russia, Moscow). Skin prick tests (SPT) with food allergens were used to determine sensitization, if necessary additional SPT with aeroallergens were performed. Results. 51.9% of patients had hypersensitivity to at least 1 allergen. Positive SPT for egg were detected in 38.0%, cow's milk - in 27.8%, fish - in 10.1%. Allergy to fish occurred predominantly in the 2nd year of life (35.0% vs 4.8, p=0.02). Soy, peanuts, and nuts were detected in less than 5% of patients. At 2-6 months of age, sensitization was found in 36.4%, and after 6 months in 57.9% (p=0.08). In the group with FA before 6 months of age (n=8), 7 patients were sensitized to egg and 6 to milk. The prevalence of milk and egg allergy did not differ between exclusively breastfed and formula-fed children. Hypersensitivity to allergens was found in 4 of 10 breastfeeding patients, for compared to 3 of 11 exclusive formula-feeding patients (p=0.66). Acute allergic reactions were reported in 6.3% of patients with AD, which was 12.2% of children with FA. Triggers were egg (n=5) and fish (n=4). Anaphylaxis did not occur until 6 months of age. The frequency of severe reactions was about the same in children 1st and 2nd years of age (p=0.64). SPT urticaria size, defined in points (max=4), did not differ between children 2-24 months of age. Egg and nut allergens showed the maximum skin reaction: medians were 3 [2; 4] and 1.5 [0.75; 2.5] points. Milk allergens caused significantly less reaction compared with egg (p<0.01). These differences were absent when comparing reactions to individual milk serum fraction proteins and reactions to egg. Hypersensitivity to non-food allergens was found in 41.5% of children with FA (21.5% of children with AD), mainly sensitization to cat epithelium, birch, house dust and dog epithelium was detected. Conclusion. Sensitization to milk proteins and eggs is the leading since 2 months of age, without differences in relation to the age of the infant and the type of feeding. In all cases of moderate AD, SCT is applicable in children 0-2 years of age, with practically no age restrictions.

Validation of Practical Pathway in Patients With Anaphylaxis to Low Osmolar Contrast Media: A Retrospective Cohort Study

BACKGROUND

An optimal strategy for choosing safe alternative low osmolar contrast media (LOCM) has not yet been established in patients with a history of LOCM-induced anaphylaxis.

OBJECTIVES

To validate the practical pathway in patients with anaphylaxis to LOCMs and to compare 2 different doses of challenge testing with skin test-negative LOCM.

METHODS

A retrospective cohort study was performed in patients with LOCM-induced anaphylaxis. Patients were challenged with intravenous LOCMs showing negativity in the skin test according to 2 different protocols: low-dose and high-dose (maximum dose 10 and 30 mL, respectively). Challenge-negative LOCMs were selected for use during computed tomography scans, and patients received intravenous pretreatment with 4 mg chlorpheniramine and 40 mg methylprednisolone.

RESULTS

Of the 110 challenge tests, there were 4 (3.6%) positive challenges. Among 106 enhanced computed tomography scans performed using challenge-negative LOCMs, breakthrough reactions occurred in 8 (7.6%). Breakthrough reaction rates were not statistically different between the 2 protocols (8.9% and 6.0% in the low-dose challenge and the high-dose challenge, respectively). Compared with the low-dose protocol, the number needed to test of the high-dose challenge test decreased 2.5-fold. Moreover, none of the patients in the high-dose challenge group incurred severe reactions during computed tomography scans with challenge-negative LOCM, whereas 80% of reactions were severe in the low-dose challenge group.

CONCLUSIONS

We validated a pathway consisting of a battery of skin testing to LOCMs and challenge with skin test-negative LOCM in patients with LOCM-induced anaphylaxis.

Contrast Medium Hypersensitivity: A Large Italian Study with Long-Term Follow-Up

Hypersensitivity reactions (HRs) to contrast media (CM) are a major problem. We compared differences of HRs to iodinated contrast media (ICM) versus gadolinium-based contrast media (GBCM), collecting data on prevalence, type, latency and severity. Secondly, the predisposition to perform new contrast tests, use of premedication and possible appearance of new reactions were explored in a long-term follow-up of 5 years. Clinical data, comorbidities, skin test (ST) results, re-exposure to CM procedures with any new reactions, premedication and CM used were collected. In a retrospective single-center study, 350 patients with mild to moderate HRs were enrolled. Asthma, food allergy, non-allergic drug hypersensitivity and neurologic disease were significantly more frequent in patients with HRs to GBCM compared to the high evidence of cardiovascular disease and history of cancer in patients with HRs to ICM. A marked delay in performing STs was reported by patients with negative results (66 months, p < 0.01). Iomeprol, iopamidol and gadobenic acid were the culprit CM most involved in HRs in patients with positive STs. During follow-up, 7.1% of responders reported new HRs to CM despite negative STs, premedication and infusion of alternative CM in most cases.

New diagnostıc perspectives in the management of pediatrıc beta-lactam allergy

Since overdiagnosis of beta-lactam (BL) allergy is common in the pediatric population, delabeling is a critical part of antimicrobial stewardship. Undesirable consequences of inaccurate BL allergy labeling can be handled by incorporating traditional delabeling or newer risk-based strategies into antibiotic stewardship programs. Conventional assessment of BL allergy relies upon a stepwise algorithm including a clinical history with skin testing followed by drug provocation tests (DPTs). However, a growing number of studies highlighted the suboptimal diagnostic value of skin testing in children. Recently, there has been a paradigm shift in the practice of BL allergy assessment due to recent challenging data which emphasize the safety and accuracy of direct DPTs in children with a suspicion of non-immediate mild cutaneous reactions such as maculopapular eruption, delayed urticaria, and possibly also for benign immediate reactions such as urticaria/angioedema. Identifying low-risk BL allergy patients, in whom skin tests can be skipped and proceeding directly to DPTs could be safe, has become a hot topic in recent years. New risk stratification and predictive modeling studies that have the potential to better predict BL allergy risk status have recently been introduced into the field of drug allergy, particularly in adults. However, in contrast to adults, risk assessment studies in children are rare, and optimal risk definitions are controversial. In the coming years, promising potential methods to elucidate the predictors of BL allergy in children will require multidimensional approaches that may include predictive analytics, artificial intelligence techniques, and point-of-care clinical decision tools.

Comparative Assessment of Platinum Salts and Taxane Group Hypersensitivity Reactions, The Role of Skin Tests in Diagnosis?

PURPOSE

We aimed to investigate the role of skin tests (ST) in the diagnosis of hypersensitivity reactions (HSRs) with platinum salts (PS) and taxane (TX) groups drugs and their reliability in patient management.

MATERIALS AND METHOD

Patients' data who developed immediate HSR with PS and TX were recorded and ST was performed. The gradual challenge was applied to all patients with ST negative and grade 1-2 with the suspect drug.

RESULTS

In total, the data of 104 patients (74 with PS, 30 with TX) who developed HSR against PS and TX were shared. The gradual challenge was applied to 72 ST negative and grade 1-2 patients (46 PS group, 26 TX group). The gradual challenge was negative in 39 patients in the PS group and 23 patients in the Tx group. The negative predictive value (NPV) for PS was 83% and NPV for TX was 88%. We found significantly higher skin test positivity in patients with PS and TX and grade 3 HSR (p = 0.007, p = 0.001). A significant correlation was found between skin test positivity and early onset of symptoms (p = 0.001 for PS, p = 0.015 for TX). In terms of symptoms witnessed in HSR, we observed the itching, urticaria, hypotension, syncope, and abdominal pain symptoms significantly more in the group with a positive skin test (p < 0.024, p < 0.001, p < 0.001, p < 0.002, and p < 0.025, respectively).

CONCLUSIONS

We found very high NPV values for PS and TX. We found that the gradual challenge applied to patients with negative skin tests is reliable if Grade 3 HSR is not observed and with this approach, unnecessary desensitization processes and/or drug alterations can be avoided.

Ineffectiveness of Skin Tests in Predicting Allergic Reactions Induced by Chinese Herbal Injections

OBJECTIVE

To evaluate whether skin tests are suitable to predict the allergy reactions induced by Chinese herbal injections (CHIs).

METHODS

The skin tests including skin prick tests (SPT), intradermal tests (IDT) and provocation tests including subcutaneous tests and intravenous tests were administered to 249 healthy subjects and 180 allergic patients for 3 CHIs, including ginkgolide injection, diterpene ginkgolide meglumine injection and Salvianolate lyophilized injection. The results of the provocation tests were used as the "gold standard" to determine the sensitivity and specificity of the skin tests.

RESULTS

The results did not show any significant differences between the healthy and allergy groups in both skin tests and provocation tests (P>0.05). The specificities of SPT and IDT were 0.976 and 0.797, respectively, and the sensitivities of both SPT and IDT were 0.

CONCLUSION

Skin tests are insufficient to predict the likelihood of allergic reactions resulting from CHIs. (ChiCTR-CPC-15006921).

Skin Testing With Peach Peel Extract Versus Serum IgE to Pru p 3 as a Stronger Predictor of Peach-Induced Anaphylaxis

The most important peach fruit allergen is Pru p 3, followed by Pru p 1, Pru p 4, and Pru p 7. We aimed to assess their role in subjects with peach fruit-induced allergy (anaphylaxis and OAS) and compare skin prick tests (SPT) vs. specific immunoglobulin E (sIgE) for predicting anaphylaxis. We also selected a control group. SPT included prevalent inhalant and plant food allergens plus peach peel extract. The sIgE to Pru p 1, Pru p 3, Pru p 4, and Pru p 7 were quantified. Compared with controls (n = 42), cases (n = 41) were younger (P = 0.003), more frequently female (P < 0.05) and had higher SPT positivity to peach peel (44% vs. 2.4%, P < 0.0001). There were significant differences in sensitization to several pollens: Olea europaea, Artemisia vulgaris, Prunus persica, Platanus acerifolia (all P < 0.001); and fruits: apple (P < 0.04), peanut (P < 0.002), tomato (P < 0.005), and melon (P < 0.05). Pru p 3 sIgE was detected in 61% of all cases (85% anaphylaxis and 38% OAS; P < 0.01 each) and 5% of controls (P < 0.001). Pru p 4 sIgE was present in 19% of cases and 7% of controls. The sIgE to Pru p 1 and Pru p 7 were not found. The odds ratio to predict anaphylaxis for peach peel SPT was 113 (confidence interval [CI], 20–613; P < 0.0001); for sIgE to Pru p 3, 22 (CI, 5.3–93; P < 0.0001); and for SPT positivity to selected plant food allergens, 5 (CI, 1–19; P < 0.05). In our study group, SPT with peel peach extract was a better predictor of anaphylaxis than Pru p 3 sIgE or other variables considered. The role of sIgE to Pru p 1, Pru p 4, and Pru p 7 seemed negligible.

IgE-Mediated Reaction to Levamisole: Evaluation of a Patient With Severe Anaphylaxis

Levamisole has been used as adjuvant immunomodulatory therapy for certain conditions such as amyotrophic lateral sclerosis (ALS). We present a case of a 70-year-old man with ALS who was started on levamisole with adequate response. Within 10 days of treatment, he developed a maculopapular non-pruritic rash on his extremities, and the medication was discontinued. However, two days later, he developed angioedema of the face and hands, urticaria in the extremities and torso, and throat closing sensation that was successfully treated in the emergency department with epinephrine, systemic corticosteroids, and antihistamines. Eight hours later, he presented with recurrent facial angioedema. He was transferred to the ICU and received two more doses of epinephrine and intravenous methylprednisolone. The patient fully recovered within 72 hours and was discharged with the indication to avoid levamisole. One month after the reaction, skin tests (prick and intradermal) with 10-fold dilutions of 550 mg/mL levamisole were positive at a concentration of 55 mg/mL (1:10 dilution). Since the patient developed anaphylaxis and tested positive for levamisole on intradermal testing, and after discussing the options with him, we decided to advise against using this medication since the benefits did not outweigh the risks of administration. This case highlights that IgE-mediated reactions to levamisole, while rare, can occur and be life-threatening. Shared decision-making should be done between patients and physicians after open, evidence-based discussions.

Patch tests in nonimmediate cutaneous adverse drug reactions: The importance of late readings on day 4

BACKGROUND

Patch tests (PTs) with two readings have been used for decades to identify the culprit drug in nonimmediate cutaneous adverse drug reactions (NICADRs), followed more recently by late reading of intradermal tests (IDTs). Some teams tend to perform PTs with only one reading before IDTs or even directly perform IDTs.

OBJECTIVES

To evaluate the relevance of a late PT reading on day 4 (D4) in NICADRs.

METHODS

We retrospectively selected patients who had a PT for an NICADR between July 2014 and March 2020.

RESULTS

During the study period, 328 patients had a PT with available results. Among the 75 positive-PT patients with available data for the two readings, 41 (54.7%) had positive results on D2 and D4 and 34 (45.3%) had negative results on D2 but positive results on D4. No patient had positive results on D2 and negative results on D4.

CONCLUSION

This study shows that a D4 reading enhanced the PT-positive results. A positive PT result allows for reducing the number of IDTs, which are more difficult and costly to perform. Our series suggests that a late PT reading at D4 should be performed for exploring NICADRs.

Skin tests for the exploration of hypersensitivity reactions associated with iodinated contrast media

BACKGROUND

Iodinated contrast media (ICM) are responsible for multiple side effects, especially hypersensitivity reactions. These reactions can either be authentic allergies, or non-allergic hypersensitivity reactions. Skin tests (prick and intradermal tests) are simple to perform and can be of great help, especially if the ICM need to be re-used. The aim of the study was to assess the characteristics of the patients in whom skin tests were performed, and the results of these tests.

METHODS

This is a retrospective study from June 2014 to June 2019. All included patients had at least one episode of hypersensitivity reaction to ICM and underwent skin tests.

RESULTS

We included 35 patients aged 18 to 85 years. The iopromide was the most implicated ICM. The reactions were mainly cutaneous (n=30) and immediate (n=27). The skin tests were negative, except for two patients. The reuse of ICM occured in 11 patients: 9 with an ICM other than the one suspected and two patients with the same ICM. Among these patients, 5 did not have any premedication. Two of them had a second hypersensitivity reaction, the first with another ICM and the second with the same ICM.

CONCLUSION

One of the main pillars of allergic exploration is ICM skin testing, not only to prevent recurrence, but also to allow patients to benefit from ICM reuse, which are sometimes essential.

Preparations of exploration of immediate hypersensitivity to antineoplastic agents: An oncology pharmacy perspective

BACKGROUND

Cancer patients are being exposed to antineoplastic drugs more frequently and for longer periods, resulting in a higher risk of hypersensitivity reactions. The aim of this study was to assess the pharmaceutical time and direct cost of drug allergy explorations following immediate hypersensitivity reactions to antineoplastic agents.

METHODS

A micro-costing method was used to collect data on consumption of human and material resources for allergy exploration preparations. The monetisation was carried out on the basis of prices and hourly wage costs applied in 2018. The number and type of allergy explorations prepared by the pharmacy as well as nature of antineoplastic drugs tested, and the number of culprit drugs reintroductions were collected.

RESULTS

Almost 1.5 h is required to realise allergy tests for one patient including pharmacist time for prescription analysis and pharmacy technician's time for tests preparation. The mean manufacturing cost of these tests is estimated at €62.87 (€57.82-65.49) per culprit drug for one patient. Programming patients according to culprit drugs tested allows rationalising healthcare provider time and increasing efficiency. From January 2010 to December 2018, 277 patients were tested and 490 allergy explorations were performed, corresponding to more than 5000 preparations. Mostly, the culprit drug could be reintroduced (n = 383, 78.2%) allowing patients to receive the best possible treatment.

CONCLUSION

Management of hypersensitivity reactions is constantly progressing, as it contributes to improving patient care in oncology. This activity is time-consuming for the pharmacy team but allows patients with previous hypersensitivity reaction to continue effective treatment.

Prick, patch or blood test? A simple guide to allergy testing

This article provides information on allergy testing and serves as a simple guide for physicians who are considering using allergy testing as a step in patient management. Basic principles of allergy testing, indications for testing, and how and when to choose a suitable allergy test are discussed. Allergy testing in general refers to evaluation of either type I or type IV hypersensitivity reactions. The type I (immediate) reaction is evaluated using the skin prick test (in vivo) or serum IgE (in vitro) test methods, while the type IV (delayed) reaction is determined via the skin patch test method. The allergens responsible for a specific reaction can be identified from allergy testing, and this information is useful in administering avoidance measures. Appropriate treatment of allergic reactions along with allergen avoidance ensure a successful treatment outcome and prevent future reactions.

Allergic reactions to midazolam: A case series from an Italian allergy unit

Midazolam is a short-acting benzodiazepine with central nervous system depressing action, commonly used for conscious sedation for various procedures and for its pharmacologic properties.In literature, severe adverse reactions to this drug are described, but only in few cases positive allergological tests were demonstrated.The authors collected herein five clinical cases of different allergic reactions to midazolam demonstrated by positive skin tests.

Description of a pharmacist-managed/administered penicillin allergy skin testing service at a community hospital

PURPOSE

To describe how a pharmacist-managed and pharmacist-administered penicillin allergy skin testing (PAST) service was incorporated into an antimicrobial stewardship program at a community hospital.

METHODS

A pharmacist-managed/administered PAST service was initiated in October 2015. Patients 18 years of age or older were considered for PAST if they had a reported history of a type I or unknown type of allergic reaction to penicillin that occurred more than 5 years previously. Patients with a vague allergy history were considered for PAST if the provider was uncomfortable prescribing a preferred β-lactam out of concern for penicillin allergy. Patients were excluded if they were pregnant, had a history of a non-type I allergic reaction, or recently received antihistamines. The primary outcome was the percentage of patients who underwent PAST and were subsequently transitioned to a preferred β-lactam.

RESULTS

PAST was initiated in 90 patients from October 2015 to December 2019. Eighty-five out of 90 patients (94%) completed PAST. Seventy-six out of 90 patients (84.4%) who underwent PAST were transitioned to a preferred β-lactam. The most commonly administered antibiotics prior to PAST were vancomycin, cefepime, and metronidazole. The most commonly used antibiotics after PAST were penicillin, piperacillin/tazobactam, and ampicillin/sulbactam. Among the 90 patients who underwent PAST, alternative antibiotics were avoided for a total of 1,568 days, with a median of 11 days (interquartile range, 6-18 days) avoided per patient.

CONCLUSION

Incorporating a pharmacist-managed/administered PAST service into a community hospital's antimicrobial stewardship program can improve the utilization of preferred antimicrobial therapy and help avoid use of more toxic, costly antimicrobials.

Patch testing of budesonide in Italy: The SIDAPA baseline series experience, 2018-2019

BACKGROUND

Budesonide was included in the European Baseline Series in 2000 as the most suitable marker forcorticosteroid hypersensitivity. In the last two decades, a decreasing trend of budesonide allergy has been observed.

OBJECTIVES

To estimate the prevalence of positive patch test reactions to budesonide in a large, Italian patch test population, characterizing patients according to MOAHLFA index and evaluating the benefit with extended readings of budesonide patch test.

METHODS

Retrospective analysis of patient demographics and patch test results over a 2-year period (2018-2019) was performed at 14 patch test clinics in Italy.

RESULTS

Ninety out of 14 544 (0.6%) patients reacted to budesonide 0.01% pet.. Positive reactions were mild in 54.4% and late readings at day 7 showed new positive reactions in 37.8% of patients. The MOAHLFA index showed a significant positive association with male gender, atopic dermatitis, and age >40 years and a significant negative association with hand and face dermatitis.

CONCLUSIONS

We documented a low prevalence of budesonide allergy in Italy, confirming its decreasing trend recently reported in the literature. Nevertheless, budesonide needs to be maintained in the baseline series for its good ability to detect corticosteroid sensitization.

Betalactam hypersensitivity: The importance of delabelling in primary care

PATIENTS AND METHODS

An allergy work-up was performed on adult patients with a history of a penicillin allergy seen by primary medical care in Monastir (Tunisia) between July 2016 and February 2018. Patients with negative skin tests were challenged with amoxicillin. Patients who were delabelled were contacted by phone after 6 months to determine outcomes after any therapeutic penicillin-class antibiotic intake.

RESULTS

A total of 39 patients were evaluated and 33 (84.6%) were delabelled. Five patients were penicillin skin-test positive and one was oral challenge positive. We succeeded in contacting 33 delabelled patients at 6 months. Twenty-two patients tolerated a subsequent therapeutic course of amoxicillin, eight patients did not retake penicillin due to a lack of therapeutic indication, and three patients refused an indicated penicillin use fearful of another reaction.

CONCLUSION

This study highlights the importance of allergy work-up in the diagnosis of beta-lactam hypersensitivity. Most patients were excessively labelled as beta-lactam allergic and this mislabelling could increase healthcare costs and lead to the development of drug resistance by the use of wide-spectrum antibiotics.

Coccidioidomycosis Skin Testing in a Commercially Insured Population, United States, 2014-20171

Coccidioidomycosis skin testing appears to be uncommon, based on US health insurance claims data. Patient demographic features were consistent with the approval of the test for adults, but few patients had previous coccidioidomycosis diagnosis codes supporting its use for detecting delayed-type hypersensitivity in those with a history of pulmonary coccidioidomycosis.

Identification of Risk Factors and Cross-Reactivity of Local Anesthetics Hypersensitivity: Analysis of 14-Years' Experience

Purpose

Local anesthetics (LA) are widely used and adverse drug reactions (ADR) occur in 2.5–10%, but hypersensitivity reactions are rare (ranging between 0% and 4.3%). Risk is so overestimated causing too many allergy clinic referrals. There are limited and also conflicting results over the management of LA allergy. We aimed to find out who should be referred to an allergy clinic for a LA allergy testing, to define the subjects with an increased risk of LA allergy and to assess the need for testing for identifying alternative LA.

Patients and Methods

We performed a retrospective study of patients referred to our clinic for diagnostic workup of LA hypersensitivity from 2006 to 2020.

Results

In our cohort of 398 patients, tests were positive in 14 (3.52%) of them. Personal history of ADR with LA was the only independent risk factor for positive test (RR=4.007, p=0.033). Presence of generalized cutaneous symptoms and hypotension during past reaction were independent predictors of positive test (RR=9.043, p=0.021 and RR=10.445, p=0.038, respectively). The negative predictive value of intradermal test at dilution of 1:100 for immediate-type reaction was high (97.56%). Also, we demonstrated cross-reactivity within the amide-group LAs and co-occurrence of immediate- and delayed-type reactions.

Conclusion

Only patients with an LA-induced ADR should be referred to an allergy clinic. History of generalized cutaneous symptoms and/or hypotension during the reaction may define subjects with an increased risk of LA allergy. A stepwise test procedure may start with skin tests especially for these patients with increased risk factors. In presence of LA allergy, alternative LA should always be confirmed by performing a challenge test.

β-Lactam Allergy and Cross-Reactivity: A Clinician's Guide to Selecting an Alternative Antibiotic

β-Lactams which include penicillins, cephalosporins, carbapenems, and monobactams are the most common antibiotic classes reported to cause allergic reactions to drugs. This review is mainly about published studies assessing the cross-reactivity among β-lactams in penicillin- or cephalosporin-allergic subjects by carrying out diagnostic tests with alternative β-lactams and, if appropriate, graded challenges. Several studies demonstrated that cross-reactivity connected with the β-lactam ring, causing positive responses to allergy tests with all β-lactams, is infrequent in subjects with an IgE-mediated allergy and anecdotal in those with a T-cell-mediated allergy. Identities or similarities of β-lactam side-chain structures are mainly responsible for cross-reactivity among these antibiotics. For example, in aminopenicillin-allergic subjects, cross-reactivity with aminocephalosporins could possibly be over 30%. On the other hand, in a few prospective studies of penicillin-allergic individuals, less than 1% of cases show a cross-reactivity between penicillins and both aztreonam and carbapenems. Particular patterns of allergy-test positivity observed in some studies that assessed cross-reactivity among β-lactams seem to indicate that prior exposures may be responsible for coexisting sensitivities. Therefore, pre-treatment skin tests with the related β-lactams are suggested before administering them via graded challenges to β-lactam-allergic patients who need alternative β-lactams.

Risk of True Allergy to Local Anesthetics: 10-Year Experience from an Anesthesia Allergy Clinic in China

Background

Local anesthetics (LAs) have been widely used throughout the healthcare settings, especially in local anesthesia and pain management. The incidence of allergic reactions to LAs remains uncertain. The danger of allergic reactions to the use of LAs in every day of clinical practice is a matter of great concern. Therefore, it is necessary to investigate the risk of true allergy to LAs.

Methods

This study retrospectively evaluated the medical records of patients who were referred to an anesthesia allergy clinic in China and underwent allergy tests with LAs over a 10-year period from 2009 to 2019. The following information was collected from medical records: demographics of the patients, reasons for referral, clinical features of drug hypersensitivity reaction (DHR), and test results with LAs. Skin tests combined with an in vitro method, basophil activation test (BAT), were used to investigate allergic reactions to LAs.

Results

A group of 109 patients were included in the analysis. The main reason for referral was the presence of a suspected DHR after procedures with LAs (n=68, 62%), the second most common reason for referral was a history of DHR to other drugs and the need to use LAs for upcoming procedures (n=41, 38%). Of the 68 patients with a suspected DHR to LAs, only six cases presented true allergy and showed positive results in skin tests and/or BAT. And all 41 patients who had a history of DHR to other drugs presented negative in all tests.

Conclusion

Risk of true allergy to LAs may be very low. However, patients with a suspected history of DHR to LAs should be considered for allergy tests. Skin tests and BAT may be useful in the investigation and diagnosis of true allergy to LAs in clinical practice.

Piperacillin-Tazobactam Allergies: An Exception to Usual Penicillin Allergy

Purpose

The majority of penicillin allergy labels are false, and skin tests (ST) have high negative predictive value (NPV) of up to 90%. Piperacillin-tazobactam (PT) allergy has been suspected to be an exception to this, but existing literature is scarce. We investigate the epidemiology, clinical characteristics, testing outcomes and predictive value of ST in patients referred for suspected PT allergies.

Methods

The records of all patients referred for suspected PT allergy testing and prescription rates of PT in all Hong Kong public hospitals (2015–2019) were analyzed.

Results

There was an increase in both PT prescriptions and number of newly reported PT allergies between 2015 and 2019. The majority (91.1%) of patients with suspected PT allergy had at least 1 underlying medical co-morbidity or immunosuppressant use leading to increased risk of infections. Thirty-six patients with suspected PT allergy completed ST. Two patients had positive ST, and 32/34 patients with negative ST underwent drug provocation testing (DPT). Nine of these patients were diagnosed with PT allergy based on positive DPT. Overall, 11/34 (32.4%) were diagnosed with PT allergy and the NPV of ST was 71.9%.

Conclusions

There is growing utilization of PT and corresponding cases of suspected allergies. The majority of suspected PT allergies had increased risk for recurrent infections. Unlike other penicillin allergy, there is a high rate of genuine PT allergy (up to 30%) and a poor NPV of ST (up to 70%). DPT remains the gold standard for accurate diagnosis, and all patients with a suspected allergy should undergo thorough allergy workup.

Prevalence of latex sensitivity and allergy among physicians of a residency program in a children´s hospital of Buenos Aires

Introduction

International publications estimate a 7 %-17 % latex sensitization (LS) prevalence among health care workers, but values in Argentina are unknown.

Objectives

To estimate the prevalence of latex sensitization and allergy among residents of a children's hospital using the immediate-reading prick test and to assess associated risk factors in this population.

Population and methods

Cross-sectional study. Residents, trainers, and Chief residents of the Departments of Pediatrics, Orthopedics, Surgery and Intensive Care were included between June and October 2017. All of them were administered a questionnaire (assessing atopic diseases and other risk factors) and underwent the immediatereading prick test. Total and latex-specific immunoglobulin E levels were determined in a subgroup of individuals (first- and fourth-year residents, surgical specialties, and intensive care).

Results

A total of 113 participants were included. LS prevalence was 7.96 % (95 % confidence interval: 3.70-14.58); 4 participants were allergic to latex. A history of latex-related symptoms (LRS) was significantly associated with a positive result in the immediate-reading prick test (p = 0.0196; odds ratio: 6.13; 95 % confidence interval: 1.44-26.04). There was no association between LS and the year of the residency program.

Conclusions

The observed LS prevalence was 7.9 %. There was a significant relation between a history of LRS and a positive result in the immediate-reading prick test.

Accuracy of penicillin allergy diagnostic tests: A systematic review and meta-analysis

BACKGROUND

Having a penicillin allergy label associates with a higher risk for antibiotic resistance and increased health care use.

OBJECTIVE

We sought to assess the accuracy of skin tests and specific IgE quantification in the diagnostic evaluation of patients reporting a penicillin/β-lactam allergy.

METHODS

We performed a systematic review and diagnostic accuracy meta-analysis, searching on MEDLINE, Scopus, and Web of Science. We included studies conducted in patients reporting a penicillin allergy and in whom skin tests and/or specific IgE quantification were performed and compared with drug challenge results. We quantitatively assessed the accuracy of diagnostic tests with bivariate random-effects meta-analyses. Meta-regression and subgroup analyses were performed to explore causes of heterogeneity. Studies' quality was evaluated using QUADAS-2 criteria.

RESULTS

We included 105 primary studies, assessing 31,761 participants. Twenty-seven studies were assessed by bivariate meta-analysis. Skin tests had a summary sensitivity of 30.7% (95% CI, 18.9%-45.9%) and a specificity of 96.8% (95% CI, 94.2%-98.3%), with a partial area under the summary receiver-operating characteristic curve of 0.686 (I² = 38.2%). Similar results were observed for subanalyses restricted to patients reporting nonimmediate maculopapular exanthema or urticaria/angioedema. Specific IgE had a summary sensitivity of 19.3% (95% CI, 12.0%-29.4%) and a specificity of 97.4% (95% CI, 95.2%-98.6%), with a partial area under the summary receiver-operating characteristic curve of 0.420 (I² = 8.5%). Projected predictive values mainly reflect the low frequency of true penicillin allergy.

CONCLUSIONS

Skin tests and specific IgE quantification appear to have low sensitivity and high specificity. Because current evidence is insufficient for assessing the role of these tests in stratifying patients for delabeling, we identified key requirements needed for future studies.

Perioperative anaphylaxis in children: Etiology, time sequence, and patterns of clinical reactivity

BACKGROUND

Perioperative anaphylaxis (PA) in children is an uncommon but potentially life-threatening complication associated with anesthesia. Early identification and management of PA is essential to optimize clinical outcomes.

METHODS

We performed a retrospective study of anesthesia records from pediatric patients with PA from centers in the United Kingdom, France, and the United States over a period of 10 years. Time sequence of clinical signs and physiological variables during PA were collected, along with results of allergy testing.

RESULTS

Twenty-nine children with PA were included. Median age was 11 years. Based on the modified Ring and Messmer Grading Scale, severe reactions were seen in 25 (86%) members of this cohort, with 4 (14%) experiencing cardiac arrest. Life-threatening hypotension was the first clinical sign of PA in 59% of cases, followed by tachycardia and bronchospasm. In 16 (55%) cases, the initial signs of PA involved multiple organ systems. When the initial signs of PA were cardiovascular and/or respiratory, more epinephrine doses were administered. Average time from initial sign of PA to treatment with epinephrine was 6 minutes (SD: 6, range: 1-25). The causative allergen was identified in 15 patients.

CONCLUSION

Severe hypotension is the most common presenting sign of PA in children. Initial cardiovascular and/or respiratory signs are associated with the need for increased epinephrine doses. Further studies should optimize the prediction, identification, and early management of PA in children.

Blood or skin: what is best in predicting cow's milk allergy diagnosis?

Summary

Cut-off values for both skin prick tests (SPT) and specific IgE (sIgE) levels for predicting cow´s milk allergy (CMA) diagnosis are not universally defined. This study is a retrospective analysis of consecutive children (0-18 years-old) with suspected CMA tested with SPT and sIgE for cow's milk (CM) and its fractions between 2016-2017. CMA diagnosis was defined by a positive oral food challenge or a highly suggestive clinical history of CMA and SPT and/or sIgE positive to CM and/or its fractions. One hundred and five patients were included, 58% males with a median age of 2.5 (P25-P75:1-6) years and the diagnosis was confirmed in 83 patients (79%). The variables associated with CMA diagnosis were SPT with CM (p minor 0,05) and casein (p minor 0,05) and all sIgE to CM and its fractions (alfa Lactalbumin, beta Lactoglobulin and casein; p minor 0,05 for all). Optimal cut39 off points (Youden's index) for CMA diagnosis were, for the mean wheal diameter, to CM milk of 4.5mm and to casein of 3mm. For sIgE levels the optimal cut-off points were: for CM of 4.36 kUA/L, alfa-lactalbumin of 1.6 kUA/L, beta-lactoglobulin of 1.7 kUA/L and for casein of 2.6 kUA/L. The role of SPT and sIgE levels to cow´s mlik and its fractions is unequivocal in CMA follow-up. Moreover, sIgE levels seem to be more discriminatory than SPT.

Skin tests and challenge-based drug allergy diagnosis: a retrospective study of patients with confirmed drug allergy

Summary

Objectives. To describe clinical manifestations and performed diagnostic workup, focusing drug challenge tests (DCT), in patients with drug allergy. Methods. Retrospective study including all patients with skin tests (STs) or DCT-based drug allergy diagnosis, between 01/2014 - 06/2018 in a Portuguese allergy unit. Data were collected from electronic and paper-based clinical records. Results. We had 75 drug allergy diagnoses. Most index reactions were mild and major or equal 1 hour after drug intake. 59 (78%) diagnoses were based on DCTs, all based on multistep protocols with major or equal 3 predicted steps. Only 10% of the DCT were positive during up-dosing; timing and severity of the index reaction predicted DCT interruption during up-dosing. Conclusions. Most drug allergy diagnoses were based on multistep DCT. The identified predictors of DCT interruption during up-dosing can support the development of more personalized DCTs protocols.

Exposure to sewage water and the development of allergic manifestations in Finnish children

BACKGROUND

The hygiene hypothesis suggests that a decreased microbial load contributes to an increased risk of allergies. In the Finnish municipality of Nokia, sewage water was accidentally mixed with drinking water for 2 days. We studied the association between exposure and the emergence of allergies in children.

METHODS

Children aged 2-5 years living in the accident area and an age-matched cohort from the control municipality were recruited. Based on the questionnaires, we identified 139 children exposed to the contaminated water and selected age- and sex-matched controls for them (mean age 16.59 months at the time of the accident). Allergic symptoms and diseases were recorded by ISAAC questionnaires and skin prick tests (SPTs) performed 2 and 5 years after the accident.

RESULTS

SPT positivity at 5 years of follow-up was decreased in the children exposed to the sewage water below 1 year of age (OR 0.311, 95% CI 0.118-0.820; P = 0.019), particularly in children who did not develop gastroenteritis at exposure. In contrast, the children over 1 year of age at the exposure tended more likely to be SPT-positive at 5 years of follow-up (OR 1.997, 95% CI 0.963-4.143; P = 0.070).

CONCLUSIONS

Sewage water exposure during the first year of life, but not later, decreased the risk of IgE sensitization emphasizing the importance of age as a modulator. The modulation of IgE sensitization by the presence of clinical gastroenteritis at the exposure suggests that the nature of microbial load may have importance or alternatively shared host defense mechanisms protect from infection and atopic sensitization.

Intradermal Testing With Radiocontrast Media to Prevent Recurrent Adverse Reactions

OBJECTIVE. Adverse drug reactions (ADRs) to radiocontrast media are a significant social and economic burden and are difficult to predict. Because some ADRs to radiocontrast media may be immunologically induced, a skin test with diluted 1:10 radiocontrast media has been used to predict ADRs. However, using this test in clinical practice is difficult because of its low sensitivity. SUBJECTS AND METHODS. This study enrolled 36 patients with a history of immediate ADR to radiocontrast media who visited the Allergy and Asthma Clinic of Severance Hospital from 2017 to 2018. Patients underwent intradermal testing (IDT) with five types of diluted (1:10) and undiluted radiocontrast media (iohexol, iobitridol, iopamidol, iopromide, and iodixanol). The IDT result was regarded as positive if at least one radiocontrast medium elicited a positive reaction. Positivity of IDT and sensitivity to the culprit radiocontrast medium were calculated and compared. For subsequent CT examinations with a radiocontrast medium, the contrast agent eliciting a negative skin reaction in IDT was selected, excluding the previous culprit radiocontrast medium. RESULTS. IDT positivity and sensitivity for the culprit radiocontrast medium at 1:10 dilution were 47.2% and 47.2%, respectively, whereas the positivity and sensitivity for the undiluted radiocontrast medium were 86.1% and 75.0%, respectively. The positivity and sensitivity were higher with frequent radiocontrast medium use or with severe reaction. Of 22 patients who underwent another CT examination with the contrast medium selected on the basis of IDT results, 21 (95.5%) did not experience an ADR. CONCLUSION. IDT to prevent ADR should be performed with undiluted radiocontrast medium. Selecting an alternative radiocontrast agent on the basis of IDT results can be clinically useful to prevent recurrent ADRs to radiocontrast media.

Peri-Operative Anaphylaxis-An Investigational Challenge

Patients with suspected peri-operative anaphylaxis (POP) require thorough investigation to identify underlying trigger(s) and enable safe anesthesia for subsequent surgery. The changing epidemiology of POP has been striking. Previous estimates of the incidence of POP have ranged between 1:6,000 and1:20,000 anesthetics, but more recent data from France and the United Kingdom suggest an estimated incidence of 1:10,000. Other important changes include a change in the hierarchy of well-recognized triggers, with antibiotics (beta-lactams) supplanting neuromuscular blockers (NMB) as the leading cause of POP. The emergence of chlorhexidine, patent blue dye, and teicoplanin as important triggers have also been noteworthy findings. The mainstay of investigation revolves around critical analysis of the time-line of events leading up to anaphylaxis coupled with judicious skin testing. Skin tests have limitations with respect to unknown predictive values for most drugs/agents and therefore, knowledge of background positivity in healthy controls, test characteristics of individual drugs and the use of non-irritant concentrations is essential to avoid both false-positive and false-negative results. Specific IgE assays for individual drugs are available only for a limited number of agents and are not a substitute for skin testing. Acute serum total tryptase has a high specificity and positive predictive value in IgE-mediated POP anaphylaxis but is limited by its moderate sensitivity and negative predictive value. Planning for safe anesthesia in this group of patients is particularly challenging and consequently anesthetists need to be alert to the possibility of repeat episodes of anaphylaxis. Because of the limitations of current investigations for POP, collecting systematic data on the outcome of repeat anesthesia is valuable in validating current investigatory approaches. This paper reviews the changing epidemiology of POP with reference to the main triggers, and the investigation and outcome of subsequent anesthesia.

Skin tests are important in children with β-lactam hypersensitivity, but may be reduced in number

BACKGROUND

There is no perfect agreement on how to perform an allergy workup in suspected beta-lactam (BL)-allergic children, since skin test (ST)-induced pain is often a limitation. The aim of the study was to assess the possibility of reducing the number of ST in children when performing a complete allergy workup for BL hypersensitivity reactions.

METHODS

A retrospective analysis of all patients referring to the Allergy Unit of the University Hospital of Montpellier (France) with positive responses in immediateand non-immediate-reading ST to a BL over a 16-year period was performed, to determine the positive predictive value (PPV) of ST. All pediatric patients with a suspected BL hypersensitivity were skin-tested with the suspected drug only, during the following 54 months.

RESULTS

A total of 319 patients reporting 328 BL reactions were included in the retrospective study. The PPV of ST for the reported drug was of 99.4%. Based on the results, the number of patients to include in the prospective study was estimated to be 101. In the prospective study, 229 children were included. We diagnosed a BL hypersensitivity in 12 children (5.2%): Diagnosis was reached in 6 (50.0%) through ST (delayed reading for all) and in 6 through drug provocation test (DPT).

CONCLUSION

ST with BL should therefore be performed as a screening test, before DPT, and testing only the suspected drug may be sufficient when dealing with children.

Assessing cross-reactivity to neuromuscular blocking agents by skin and basophil activation tests in patients with neuromuscular blocking agent anaphylaxis

BACKGROUND

Following diagnosis of neuromuscular blocking agent (NMBA) anaphylaxis, identifying safe alternatives for subsequent anaesthesia is critical. A patient with anaphylaxis to one NMBA can also have an allergic reaction to other NMBAs (cross-reactivity). Whilst drug provocation testing is standard for identifying or excluding allergy, there is significant risk. In vitro, after an allergen activates basophils, basophils express surface activation markers that can be measured by basophil activation testing (BAT). We compared cross-reactivity between NMBAs assessed by BAT against that by skin testing.

METHODS

All patients attending an anaesthetic allergy clinic in Sydney, Australia between May 2017 and July 2018 diagnosed with NMBA anaphylaxis qualified for this study comparing intradermal skin tests and BAT with a panel of NMBAs (rocuronium, vecuronium, pancuronium, suxamethonium, cisatracurium).

RESULTS

Of the 61 patients participating, sensitisation on skin testing and on BAT completely matched in only nine patients (15%). Sensitisation was not in agreement for pancuronium, cisatracurium and rocuronium, but was in agreement for vecuronium and suxamethonium. Nine patients with negative skin tests subsequently tolerated cisatracurium, and one false positive on BAT to cisatracurium was detected.

CONCLUSIONS

The utility of BAT in identifying safe NMBAs for subsequent anaesthesia needs further evaluation. BAT detects a different cross-reactivity profile to skin tests. Negative skin testing and BAT might increase confidence in performing drug provocation testing, but this and follow-up of subsequent anaesthesia in our cohort is necessary to determine the clinical significance of BAT sensitisation.

Assessment of patch test results carried out during ten years in a city in southern Brazil

BACKGROUND

Contact dermatitis affects up to 20% of the population. Patch testing for contact allergy may be needed to confirm the diagnosis.

OBJECTIVES

To describe and discuss the results of patch tests performed in a city in southern Brazil.

METHODS

A cross-sectional analysis was performed on all skin test results over ten years. Variables such as gender, age at the time of testing, and test results were evaluated. Triggering factors, duration of complain, and previous medications used related to the clinical history were retrieved for some patients by reviewing their medical records.

RESULTS

The sample was composed of 539 patch tests, of which 411 (76.2%) were from women. The age of the tested subjects ranged from 5 to 87 years. The prevalence of positive reactions in the patch tests was 391 (72.5%). The most prevalent positive reaction was to nickel sulfate (196; 36.4%), which had statistical significance when associated with female gender (p<0,001).

STUDY LIMITATIONS

Database obtained through secondary sources (the reports of the exams and the medical records), occurring the incomplete registration of some information.

CONCLUSIONS

Data analysis at the local level is important to define preventive policies.

Meglumine antimoniate-induced DRESS: original case with a positive skin test

We report a case of a 64-year-old woman treated with meglumine antimoniate (Glucantime®). On day 20, she developed fever, a pruriginous skin rash and myalgia. The blood tests showed eosinophilia and hepatic cytolysis. The clinico-biological picture improved gradually and the symptoms disappeared 4 weeks after the drug withdrawal. Six weeks later, intradermal tests to Glucantime® were performed and were positive at 48 hour-reading. This clinical picture suggests DRESS induced by meglumine antimoniate. To the best of our knowledge, only one case of meglumine antimoniate-induced DRESS has been reported in the literature and we are the first to report a case confirmed by skin tests.

Current practice of allergy diagnosis and the potential impact of regulation in Europe

In the European Union (EU), the regulatory framework regarding diagnostic allergen extracts is currently in the process of being implemented at the national level. Due to these regulations, the initial and periodic renewal expenses for the registration of diagnostic allergen extracts may render extract production unprofitable. Consequently, many extracts may be at risk of removal from the market. The current survey, which was conducted by a task force of the European Academy of Allergy and Clinical Immunology, aimed to assess the current practice of allergy diagnosis in Europe. This survey revealed that skin tests continue to be the main diagnostic procedure and are used as the first option in almost two-third of all types of allergic diseases and in 90% of individuals suffering from respiratory allergies. Therefore, there is a need to ensure the availability of high-quality allergen extracts to maintain the common diagnostic procedures used by EU professionals. To reach this goal, it is necessary to align efforts and establish active partnerships between manufacturers, relevant scientific societies, consumer organizations and authorities to maintain the availability of these diagnostic tools.

Nickel, chromium and cobalt: the relevant allergens in allergic contact dermatitis. Comparative study between two periods: 1995-2002 and 2003-2015

BACKGROUND

Metals are common agents of allergic contact dermatitis, occupational or not, with decreasing incidence over the last years in some countries that have regulated the amount of nickel in objects.

OBJECTIVES

To analyze and compare with previous studies the profile of metal sensitization between 2003-2015.

METHODS

Patients who underwent patch testing between 2003-2015 were evaluated retrospectively regarding the sensitization rates to metals, the associations between them, the relationship with profession and epidemiology.

RESULTS

Of the 1,386 patients tested, 438 (32%) had positive test to some metal, similar results to the 404/1,208 (33%) of the previous study (1995-2002) performed at the same service (p=0.32). The frequency of nickel (77%), cobalt (32%) and chromium (29%) changed slightly (p=0.20). Most cases of sensitization to chromium were related to the occupation (64%), in contrast to nickel and cobalt (p<0.0001). There was a predominance of females among those sensitized to metal in both studies (p=0.63) and the age group of 20-49 years old (p=0.11); the number of fair-skinned individuals increased (p<0.001), as well as the lesions in the cephalic segment (50.5%; p<0.0001) and hands (45%; p<0.0001), which are not the most frequent location anymore. The number of cleaners decreased (39% vs. 59%; p<0.0001), which still lead in front of bricklayers/painters, which increased (14% vs. 9%; p=0.013). The frequency of wet work reduced (65% vs. 81%; p<0.0001).

STUDY LIMITATIONS

The study included a single population group; only patients with positive tests to metals were considered - the others were not evaluated for the possibility of false negatives.

CONCLUSION

The sensitization to metals, occupational or not, has been significant over the last 21 years, with few epidemiological changes.

Diagnosing and managing patients with drug hypersensitivity

INTRODUCTION

Diagnosing and managing drug hypersensitivity is challenging because there are no clear limits between different types of drug reactions. Distinguishing between type A (predictable) and type B (hypersensitivity) reactions when a drug is introduced on the market is not easy. When many people use a drug, adverse reactions can occur, conditioned by diverse genetic profiles, viral infections or concomitant therapy. Occasionally the only tool clinicians have on which to base the diagnosis is the clinical history. Skins tests or in vitro tests sometimes have low sensitivity or are unavailable, and drug provocation tests may be dangerous or strictly forbidden in case of severe cutaneous reactions. Areas covered: This paper reviews the diagnosis and management of the two main types of immunological reactions: IgE-mediated immediate drug hypersensitivity reactions (IDHRs) and non-immediate drug hypersensitivity reactions (NIDHRs). Expert commentary: Although Europe and the United States use different diagnostic methods, patients with history of drug hypersensitivity must avoid the suspicious drug, and clinicians must assess tolerance to safe alternatives under medical surveillance. Sometimes desensitization may be required. There is a consensus about the need to perform genetic testing for specific drugs and give patients proper documentation to prevent future exposure to culprit drugs.

Oral challenge without skin tests in children with non-severe beta-lactam hypersensitivity: Time to change the paradigm?

Suspected allergy to penicillins and cephalosporins is very common in childhood. After a proper evaluation, allergy will be confirmed only in a small portion of them. Intradermal tests are usually part of the allergy workup, but they are painful for children and time-consuming, and their role has been debated. A systematic review found only two studies reporting a positive predictive value of skin tests in children of 36% and 33%, respectively, leading to a high rate of inaccurate diagnosis. Moreover, considering that skin tests are negative in more than 90%-95% of cases, an oral provocation test (OPT) is finally needed to confirm tolerance in most of these children. Positive OPT are rare, and even where children demonstrate reproducible signs on challenge, they rarely constitute immediate or serious symptoms. Therefore, OPT to the index antibiotic without skin tests are increasingly being considered an accepted procedure for children with a suspected mild non-immediate reaction related to a beta-lactam antibiotic. Furthermore, a recent research has taken the same approach including children with suspected mild immediate reactions, with similar safety and positive results. In light of recent evidence highlighted, it is now the time for large and multicentric studies to confirm that OPT with the index antibiotic, without skin tests, are safe and convenient for children with a history of a mild reaction with a beta-lactam antibiotic before it can be recommended in pediatric allergy guidelines.