Infusion Reactions With Alternative Therapies During the National Shortage of Iron Dextran.

Prior to the national shortage of iron dextran in early 2023, it was the most commonly administered intravenous iron infusion at our institution. After the shortage impacted the health system, alternatives such as iron sucrose and sodium ferric gluconate/sucrose were required that utilized lower doses given at more frequent patient visits. Coinciding with their more prevalent use, an increase in iron infusion reactions was observed. Our study analyzed 880 patients who received iron infusions in three Henry Ford Hospital clinics in metropolitan Detroit, Michigan, from July 2022-June 2023. The 74 reactions that occurred were most commonly associated with iron sucrose at the 500 mg dose (41/74, 55.41%, p < 0.0001). Most reactions observed across all iron formulations and doses were mild, with 83.7% being Grade 0 or 1 as defined by the United States Drug Allergy Registry (USDAR) grading scale for immediate reactions. Patients who experienced an infusion reaction were less likely to complete their infusion plans (OR 0.004 for iron dextran, OR 0.128 for iron sucrose, p < 0.0001), with infusions most commonly being completely discontinued thereafter, with a minority pursuing alternative options. More patients with lower number of doses scheduled for iron dextran completed their infusion schedules than those with more doses, but the opposite was seen for iron sucrose. We assessed the impact of the national shortage of iron dextran examining infusion reactions with various iron infusions and doses.

Differential MRGPRX2-dependent activation of human mast cells by polymyxins and octapeptins.

The emergence of multi-drug resistant Gram-negative bacteria has led to renewed interest in the antimicrobial activity of polymyxins and novel polymyxin analogues (e.g. nonapeptides and octapeptin). In some individuals, clinically used polymyxins can cause acute hypersensitivity reactions through mast cell activation, with a recent study attributing this effect to activation of the MAS-related G protein-coupled receptor X2 (MRGPRX2). In the present study, HEK293 cells expressing human MRGPRX2 and the human mast cell line LAD2 were used to characterize the activity of the broader family of polymyxins. Octapeptin C4, polymyxin B and colistin produced concentration-dependent calcium mobilization, degranulation, and CCL-2 (MCP-1) release in LAD2 mast cells, with the former being highly potent. CRISPR-Cas9 knockdown of MRGPRX2 in LAD2 cells and a MRGPRX2 inverse agonist caused a significant reduction in calcium mobilization, degranulation, and CCL-2 release, demonstrating dependency on MRGPRX2 expression. In contrast, polymyxin nonapeptides were far less potent calcium mobilisers and failed to induce functional degranulation in LAD2 cells. Our results confirm that activation of mast cells induced by polymyxin-related antibiotics is MRGPRX2-dependent and reveal that octapeptin C4 might be more liable, whilst nonapeptides are less liable, to trigger immediate hypersensitivity reactions clinically. The mechanism underpinning the difference in MRGPRX2 activation between polymyxin-related antibiotics is important to better understand as it may help design new, safer polymyxins and guide the optimal clinical use of existing polymyxin drugs.

Review: Food-induced mucosal alterations visualized using endomicroscopy.

Confocal laser endomicroscopy (CLE) is a novel technique allowing real time in vivo microscopy during standard endoscopy. Recently, acute mucosal alterations after food administration visualized by CLE have been linked to symptoms in irritable bowel syndrome (IBS). Interestingly, the observed reactions occurred in subjects without demonstrable allergic sensitization to food-this is in line with mechanistic research showing local but not systemic allergic sensitization to foods in an animal model for IBS. Here, European experts conducting CLE with food administration provide a narrative review of the available literature and propose practical guidance on the use of this technique. CLE allows physicians to observe acute mucosal reactions after the application of food to the duodenal mucosa in patients with functional gastrointestinal disorders. Some open-label interventions show a symptomatic benefit when patients exclude the nutrient that triggered an acute mucosal reaction. However, many technical, mechanistic, and clinical questions remain unanswered to date. Technically, the interobserver variability and learning curve requires systematic evaluation and criteria or cutoffs for alterations require validation. Mechanistic studies are needed to enhance our understanding of the mechanisms underlying observed alterations. Finally, rigorous blinded controlled studies are needed to assess a link of these observed alterations with symptom generation. CLE offers a platform allowing scientific insights related to food induced acute mucosal alterations. However, many questions remain unanswered, and more research is warranted to understand the role of acute mucosal alterations visualized upon food administration in IBS pathophysiology and treatment.

The Role of the Basophil Activation Test in the Diagnosis of Drug-Induced Anaphylaxis.

The diagnosis of drug-induced anaphylaxis (DIA) is a serious health problem. The Basophil activation test (BAT) is considered a specific in vitro provocation, and compared to in vivo provocation, it is more convenient, cheaper, and safer for the patient. This study aimed to evaluate the usefulness of the BAT in the diagnosis of DIA. This study included 150 patients referred to a reference allergy clinic with suspected drug allergies. All patients underwent a detailed clinical evaluation supplemented with the BAT. Positive BAT results were obtained in two out of 21 patients who were to receive the COVID-19 vaccine. The sensitivity and specificity of the BAT were 40% and 75% for the COVID-19 vaccine, 67% and 58% for DMG PEG 2000, and 100% and 75% for PEG 4000, respectively. Nine out of 34 patients with suspected antibiotic allergies had positive BAT results with 14 different antibiotics. Positive BAT results were also obtained with NSAIDs in two patients and with local anesthetics in three patients. The confirmation of allergy by the BAT improves the safety profile of the diagnostic work-up as it may defer the need for drug provocation, preventing potential anaphylactic reactions.

Nebivolol hydrochloride and its impurities induce pseudo-allergic reactions via mast cell activation.

Nebivolol hydrochloride is a third-generation ß-blocker commonly used to treat cardiovascular diseases. However, it has been reported to induce allergic reactions in clinical use which deserves much attention. Therefore, this study focused on the ability of two isomers of nebivolol and chiral isomer impurities to induce allergic reactions. Our findings demonstrate that both nebivolol and two isomeric impurities can activate mast cell degranulation in vitro and show significant retention on Mas-related G-protein-coupled receptor X2 (MRGPRX2)-HEK293 cell membrane chromatography. These effects were further validated in vivo, where nebivolol and impurity IP-3 were observed to cause toe swelling and mast cell degranulation in mice. Molecular docking studies revealed interactions between these compounds and key amino acids of MRGPRX2, suggesting a mechanism for the induced allergic reactions. This work lays the foundation for improving the clinical safety of nebivolol.

Amphotericin B for injection triggers degranulation of human LAD2 mast cells by MRGPRX2 and pseudo-allergic reactions in mice via MRGPRB2 activation.

Amphotericin B, a polyene macrolide antifungal agent, still plays an important role in the management of serious systemic fungal infections. Amphotericin B deoxycholate (AmBd) has been used to treat invasive fungal infections for over 60 years and remains the primary clinical formulation currently available. Anaphylactoid reactions triggered by AmBd in the clinic have been documented. However, the molecular and cellular events contributing to these reactions have not been clearly elucidated to date. This study demonstrates that the human Mas-related G protein-coupled receptor X2 (MRGPRX2) is the receptor that mediates these anaphylactoid responses. Molecular docking and cellular thermal shift assay (CETSA) indicate that AmBd exhibits potential affinity with MRGPRX2. In vitro, exposure to AmBd results in significant release of LAD2 mast cell granules and induces intracellular Ca2+ mobilization as well as activation of PLC-γ/IP3R and PI3K/AKT signaling pathways. However, these phenomena are reduced in MRGPRX2-knockdown LAD2 cells. In vivo, AmBd triggers paw swelling and a rapid drop in core body temperature in wild-type (WT) mice. However, these reactions are almost absent in MRGPRB2 (the mouse homolog of MRGPRX2) knockout mice (MRGPRB2MUT, MUT). The above results suggest that AmBd activates PLC-γ/IP3R and PI3K/AKT signaling via MRGPRX2 (in human LAD2 mast cells) or MRGPRB2 (in mice), leading to the release of mast cell granules and subsequent triggering of pseudo-allergic reactions. Taken together, this study clarifies the role of MRGPRX2 in triggering pseudo-allergic reactions to AmBd and suggests that MRGPRX2 could be a potential therapeutic target for controlling these reactions.

Safety of nab-paclitaxel following an allergic reaction to paclitaxel: A single institution retrospective study.

The goal of this study was to assess the safety of nab-paclitaxel in patients with ovarian cancer or endometrial cancer who had an allergic reaction to paclitaxel. We performed a retrospective review of patients with endometrial cancer or ovarian cancer with an allergic reaction to paclitaxel who were subsequently treated with nab-paclitaxel at the Mayo Clinic Florida from January 2016 to June 2023. A total of 43 patients with ovarian cancer (31) or endometrial cancer (12) and a paclitaxel allergic reaction were identified. All patients were pre-medicated against allergic reactions prior to paclitaxel and subsequent nab-paclitaxel. Allergic reactions to paclitaxel were mild in fourteen patients (33%), moderate in twenty-five patients (58%) and severe in four (9%) patients. None of the 43 patients had an allergic reaction to subsequent nab-paclitaxel. Our data suggests that the administration of nab-paclitaxel to endometrial cancer or ovarian cancer patients with allergic reactions to paclitaxel is safe and should be considered a preferable treatment option in this clinical situation.

Accidental allergic reactions to immediate-type food allergens in Japanese children: A single-center study.

BACKGROUND: Few studies have assessed the nature of accidental allergic reactions (AAR). We assessed the prevalence and risk factors for AAR in Japanese children. METHODS: This study included children with immediate-type hen's egg (HE), cow's milk (CM), wheat, or peanut allergy who developed allergic reactions within at least 2 years and were followed up regularly at a single national allergy center in Japan. From January to December 2020, low-dose reactivity was defined as allergic reactions to ≤250, ≤102, ≤53, or ≤ 133 mg of HE, CM, wheat, or peanut protein, respectively. The annualized AAR rate showed the number of reactions per patient per year (95% confidence interval). AAR risk factors were analyzed using multiple logistic regression. RESULTS: Of the 1096 participants, 609, 457, 138, and 90 had HE, CM, wheat, and peanut allergies, respectively. The median (interquartile range) age was 5.0 (2.3-8.6) years, 39% had completely eliminated allergenic food, and 24% had low-dose reactivity. The annualized AAR rate was 0.130 (0.109-0.153) in all sub-cohorts. Moderate and severe symptoms occurred in 50% and 0.7%, respectively, of children who experienced AAR. Multiple logistic regression revealed that low-dose reactivity was a significant risk factor for AAR in the overall and CM cohorts, respectively (p < .001 and p = .036). CONCLUSION: In this single-center study in Japan, the annualized AAR rate was relatively low during the COVID-19 pandemic; however, half of the participants with AAR had moderate to severe symptoms. Especially in the case of low-dose reactivity, children would require careful AAR risk management.

Novel insights into the heterogeneity of FOXP3 + Treg cells in drug-induced allergic reactions through single-cell transcriptomics.

This study uncovers the novel heterogeneity of FOXP3 + regulatory T (Treg) cells and their pivotal role in modulating immune responses during drug-induced allergic reactions, employing cutting-edge single-cell transcriptomics. We established a mouse model for drug-induced allergic reactions and utilized single-cell RNA sequencing (scRNA-seq) to analyze the transcriptomic landscapes of FOXP3 + Treg cells isolated from affected tissues. The study involved both in vitro and in vivo approaches to evaluate the impact of FOXP3 expression levels on the immunoregulatory functions of Treg cells during allergic responses. Techniques included flow cytometry, cluster analysis, principal component analysis (PCA), CCK8 and CSFE assays for cell proliferation, LDH release assays for toxicity, ELISA for cytokine profiling, and CRISPR/Cas9 technology for gene editing. Our findings revealed significant transcriptomic heterogeneity among FOXP3 + Treg cells in the context of drug-induced allergic reactions, with distinct subpopulations exhibiting unique gene expression profiles. This heterogeneity suggests specialized roles in immune regulation. We observed a decrease in the proliferative capacity and cytokine secretion of FOXP3 + Treg cells following allergic stimulation, alongside an increase in reaction toxicity. Manipulating FOXP3 expression levels directly influenced these outcomes, where FOXP3 deletion exacerbated allergic responses, whereas its overexpression mitigated them. Notably, in vivo experiments demonstrated that FOXP3 overexpression significantly reduced the severity of allergic skin reactions in mice. Our study presents novel insights into the heterogeneity and crucial immunoregulatory role of FOXP3 + Treg cells during drug-induced allergic reactions. Overexpression of FOXP3 emerges as a potential therapeutic strategy to alleviate such allergic responses. These findings contribute significantly to our understanding of immune regulation and the development of targeted treatments for drug-induced allergies.

Impact of asthma on severe food-induced allergic reactions: a systematic review and meta-analysis.

Summary: Background. Food allergy can range from mild to severe, life-threatening reactions with various symptoms and organ involvement. The impact of asthma on severe food-induced allergic reactions is not completely understood. In the hypothesis that asthma increases the risk of severe food-induced allergic reactions, the aim of this study is to compare the incidence of severe food-induced allergic reactions in patients with history of asthma compared with patients without history of asthma. Methods. We performed a systematic research on electronic databases, including PubMed, Scopus, and Web of Science. Observational studies, studies reporting medical characteristics of patients diagnosed with food allergy, and studies reporting medical history of patients with allergic reactions were included. The primary outcome was the incidence of severe food-induced allergic reactions in patients with history of asthma compared with patients without history of asthma. The protocol of this review was registered in PROSPERO (CRD42023448293). Results. Eight studies with a total of 90,367 patients met the inclusion criteria and were included, with a total population of 28,166 of patients with food allergy. The incidence of severe food-induced allergic reactions in patients with history of asthma compared with patients without history of asthma was increased (OR = 1.28; 95% CI 1.03-1.59; p = 0.03; I2 = 59%). Conclusions. Individuals with both food allergy and asthma are at high risk of severe, potentially fatal allergic reactions. Healthcare professionals should prioritize prevention and management strategies for these subjects.

Management and Implications of Beta-Lactam Allergies.

Beta-lactam antibiotics are essential components in the current antimicrobial treatment strategy, playing a crucial role in ambulatory patients and hospitalized patients. Despite their prominent therapeutic index, the use of beta-lactam can lead to adverse effects, with allergic reactions being the most concerning because of their severity. Additionally, the phenomenon of cross-reactivity may occur among various beta-lactam families, with side chains significantly contributing to immunological recognition, making these structures often responsible for the cross-allergic reactivity of beta-lactams. Tools to assess beta-lactam allergy include taking a patient's medical history, performing skin tests, and conducting provocation tests. This research aims to analyze the relevant aspects related to the safe administration of beta-lactam antibiotics in hospitalized patients as well as provide knowledge on the proper management of patients with such hypersensitivity, by doing systemic research. This research was made using Google Scholar and keywords such as "Beta-lactam allergy," "Hypersensitivity," "Cross-reactivity," "Desensitization," and "Beta-lactam allergy management." In conclusion, substituting a beta-lactam antibiotic with an alternative antibiotic may not always be the best management option for these patients, as it may lead to more adverse effects, be less effective, and prolong hospitalization time. It may also result in higher rates of antibiotic-resistant infections and increased medical costs, as these alternatives are often more expensive. However, an alternative within the beta-lactam family can be sought by conducting the appropriate analyses. Although cross-reactivity does not always occur among all beta-lactams, potential cross-reactivity should always be considered.

Clinical-Hematological Changes and Predictors of Severity in Acute Food Protein-Induced Enterocolitis Syndrome Reactions at Oral Food Challenge: A Multicenter Observational Study.

BACKGROUND: Oral food challenge (OFC) is the criterion standard for diagnosis of acute food protein-induced enterocolitis syndrome (FPIES). No diagnostic/prognostic biomarkers are available, and OFC assessment criteria are not validated. OBJECTIVE: To assess clinical-hematological changes and predictors of severity of FPIES reactions at OFC. METHODS: This was an observational multicenter prospective study. Children aged 0 to 18 years diagnosed with acute FPIES were recruited at follow-up OFC in 12 tertiary centers in Spain and Italy. OFC outcomes (as positive/negative/inconclusive and mild/moderate/severe) were assessed on the basis of published "2017 FPIES Consensus" criteria. Clinical characteristics were recorded, and full blood cell count was done at baseline, reaction onset, and 4 hours later. Regression analysis was performed to assess predictors of severe reactions at OFC. RESULTS: A total of 81 children had positive OFC (mild in 11% [9 of 81], moderate in 61% [49 of 81], and severe in 28% [23 of 81]). Increase in neutrophils and reduction in eosinophils, basophils, and lymphocytes were observed (P < .05). OFC was inconclusive in 19 cases despite objective signs or neutrophilia. Regression analysis showed that a 2-day OFC protocol where only 25% of an age-appropriate portion is given on day 1 (not sex, age, culprit food, cumulative dose, and previous reaction severity) was associated with reduced odds of severe reaction compared with giving multiple doses in a single day. CONCLUSIONS: Distinct hematological changes may help support FPIES diagnosis. Current OFC assessment criteria may not capture the broad spectrum of acute FPIES presentations. This 2-day protocol may be associated with a reduced risk of severe reactions. Future work should aim to develop safer OFC and non-OFC diagnostics for FPIES.

Real-world assessment of anaphylaxis and eosinophilic esophagitis with 12 SQ house dust mite SLIT-tablet sublingual immunotherapy.

Background: Sublingual immunotherapy (SLIT) with 12 SQ house dust mile SLIT-tablet (HDM SLIT-tablet) for dust mite-induced perennial allergic rhinitis is reported as effective and safe. Although serious allergic reactions (SARs) and eosinophilic esophagitis (EoE) have infrequently occurred under trial conditions, the safety of HDM SLIT-tablet challenge under real-world conditions is unknown. Objective: Our aim was to estimate the incidence of SARs and EoE due to HDM SLIT-tablet challenge. Methods: Through use of administrative data from Kaiser Permanente Southern California, this prospective observational study identified patients newly administered HDM SLIT-tablet with follow-up until SLIT discontinuation or end of study. Suspected cases of SARs and EoE were detected by using International Classification of Diseases, 10th Revision, diagnosis and Current Procedural Terminology procedure codes and medication dispensing records. A 3-member clinical review committee of allergists adjudicated suspected reactions. The incidence rate of confirmed SARs and EoE per 1000 person years of exposure were determined. Results: A total of 521 patients (93.9% adult and 6.1% pediatric) were exposed to HDM SLIT-tablet challenge from January 2018 through May 2023, for 440.4 person years of exposure. The patients' average age (SD) was 39.3 (14.1) years, 58.7% were female, 44.3% were non-Hispanic White, 40.3% had asthma, and 15.0% had gastroesophageal reflux disease. A SAR occurred in 1 adult patient, and during initial HDM SLIT-tablet challenge, SARs occurred in 2 pediatric adolescents, for an overall incidence of 6.8 SARs per 1000 patient years (95% CI = 2.2-21.1). EoE occurred in 1 adult patient, for an overall incidence of 2.3 cases of EoE per 1000 patient years (95% CI = 0.3-16.1). Conclusions: This real-world study demonstrated that SARs and EoE were infrequent events with HDM SLIT-tablet use, supporting the safety of HDM SLIT-tablets and need for physician supervision with initial challenge.

Disease burden and unmet need for acute allergic reactions - A patient perspective.

Background: Acute allergic reactions (AARs) occur shortly after exposure to an allergen, and the severity is on a continuum. Systemic corticosteroids (CS) are mainstay treatment of moderate to severe AARs, whereas those at risk of the most severe AARs (ie, anaphylaxis) are also recommended prescription of epinephrine autoinjectors. There is limited research on the impact of AARs not fulfilling the criteria for anaphylaxis. We have characterized a sample with a history of moderate to severe AARs and evaluated their self-reported disease burden (ie, daily life impact, anxiety, and treatment impediments). Methods: Survey study of adults with experience of AARs treated with CS. Participants recruited from a web-based panel and using social media were asked to complete a questionnaire related to their allergy and experience of AARs. The results were summarized for the whole sample and across subgroups with and without prescription of epinephrine. Results: The final study sample included 387 participants (80% women, mean age 41), of which 129 (33%) had at some point been prescribed epinephrine. The most common symptoms were respiratory (80%) and skin (78%) manifestations, and the mean (standard deviation, SD) self-rated severity score (scale from 0 [very mild] to 10 [very severe]) of the most recent AAR was 6.1 (2.0). More than 80% had experience of AARs interrupting daily activities and 50% of AARs that had limited work/studies or participation in leisure activities. Most of the respondents reported some degree of anxiety related to AARs and 43% had feared for their lives. Moreover, difficulties swallowing allergy medicine at an AAR was experienced by 26% and not having the medicine available when needed by 66%. Participants with prescription of epinephrine experienced more severe AARs than those without such prescription (mean [SD] severity 6.8 [2.1] vs 5.8 [1.8], p < 0.0001); however, also those without epinephrine prescription reported considerable anxiety and impact on daily life and to a similar degree as those with prescription. Conclusions: In this sample, subjects with experience of AARs treated with CS showed a considerable disease burden with anxiety and interruption on daily life, as well as problems related to access to, and swallowing of, medication. Although respondents with epinephrine prescription had more severe disease, a high disease burden was also evident among those without epinephrine. The study increases the knowledge of people with moderate to severe AARs, a patient population that has previously been underrepresented in the research literature.

Perioperative Cefazolin for Total Joint Arthroplasty Patients Who Have a Penicillin Allergy: Is It Safe?

BACKGROUND: Cefazolin is the standard of care for perioperative antibiotic prophylaxis in total joint arthroplasty (TJA) in the United States. The potential allergic cross-reactivity between cefazolin and penicillin causes uncertainty regarding optimal antibiotic choice in patients who have a reported penicillin allergy (rPCNA). The purpose of this study was to determine the safety of perioperative cefazolin in PCNA patients undergoing primary TJA. METHODS: We identified all patients (n = 49,842) undergoing primary total hip arthroplasty (n = 25,659) or total knee arthroplasty (n = 24,183) from 2016 to 2022 who received perioperative intravenous antibiotic prophylaxis. Patients who had an rPCNA (n = 5,508) who received cefazolin (n = 4,938, 89.7%) were compared to rPCNA patients who did not (n = 570, 10.3%), and to patients who did not have an rPCNA (n = 43,359). The primary outcome was the rate of allergic reactions within 72 hours postoperatively. Secondary outcomes included the rates of superficial infections, deep infections, and Clostridioides difficile infections within 90 days. RESULTS: The rate of allergic reactions was 0.1% (n = 5) in rPCNA patients who received cefazolin, compared to 0.2% (n = 1) in rPCNA patients who did not (P = .48) and 0.02% (n = 11) in patients who have no rPCNA (P = .02). Allergic reactions were mild in all 5 rPCNA patients who received cefazolin and were characterized by cutaneous symptoms (n = 4) or dyspnea in the absence of respiratory distress (n = 1) that resolved promptly with antibiotic discontinuation and administration of antihistamines and/or corticosteroids. We observed no differences in the rates of superficial infections (0.1 versus 0.2%, P = .58), deep infections (0.3 versus 0.4%, P = .68), or C difficile infections (0.04% versus 0%, P = .99) within 90 days in rPCNA patients who received cefazolin versus alternative perioperative antibiotics. CONCLUSIONS: In this series of more than 5,500 patients who had an rPCNA undergoing primary TJA, perioperative prophylaxis with cefazolin resulted in a 0.1% incidence of allergic reactions that were clinically indolent. Cefazolin can be safely administered to most patients, independent of rPCNA severity. LEVEL OF EVIDENCE: III.

Detection of iodixanol-induced allergic reaction signals in Chinese inpatients: a multi-center retrospective database study using prescription sequence symmetry analysis.

Objective: This study aimed to explore the signal detection method for allergic reactions induced by inpatient iodixanol injection. Methods: A database of 3,719,217 hospitalized patients from 20 large Chinese general hospitals was processed and analyzed using the prescription sequence symmetry analysis (PSSA) method. Results: 126,680 inpatients who used iodixanol and were concurrently treated with anti-allergic drugs were analyzed. In the medical records of these patients, only 32 had documented iodixanol allergies. Statistical analysis identified 22 drugs in 4 categories-calcium preparations, adrenergic/dopaminergic agents, glucocorticoids, and antihistamines-as marker drugs. With time intervals of 3, 7, and 28 days, the adjusted sequence ratios (aSRs) for all anti-allergics and the 4 categories were greater than 1. The 7-day aSRs were 2.12 (95% CI: 2.08-2.15), 1.70 (95% CI: 1.68-1.73), 3.85 (95% confidence interval [CI]: 3.75-2.30), 2.30 (95% CI: 2.26-2.35), and 1.95 (95% CI: 1.89-2.02), respectively. The proportions of adverse drug events indicated by each signal were as follows: all anti-allergics (2.92%-3%), calcium gluconate (0.19%-0.52%), adrenergic/dopaminergic agents (2.20%-3.37%), glucocorticoids (3.13%-3.76%), and antihistamines (1.05%-1.32%). Conclusion: This first multi-center Chinese inpatient database study detected iodixanol-induced allergy signals, revealing that reactions may be much higher than those in collected spontaneous reports. Iodixanol risk exposure was closer to actual pharmaceutical care findings. PSSA application with ≤7-day intervals appears better suited for monitoring late allergic reaction signals with these drugs.

Risk Factors Associated with Severe Systemic Allergic Reaction after Wasp Sting in Subjects with a History of European Hornet Sting Allergy.

Aim: To make the treatment approach in patients suffering a European hornet sting allergy reaction more personalized, preparing them also for possible future risks. Methods: In Slovenia an extended retrospective observational cohort epidemiological study about the natural history of Hymenoptera venom sensitivity is in progress. The study is based on data from the healthcare records of the University Clinic Golnik (UCG) and data collected by a questionnaire sent to patients from May 2019 to April 2021. For a pilot study, we selected patients who were referred to UCG because of an allergic reaction to European hornet sting and had been re-stung later by a wasp (n=68). The association between severe systemic allergic reactions (SSAR) after wasp sting and potential risk factors in subjects with a history of hornet sting allergy was assessed univariately using the likelihood ratio test. Results: Among 68 European hornet allergic patients 27 reacted with an SSAR and 41 reacted with a mild SAR. Among 27 patients with SSAR, 4 reacted with an SSAR also to a subsequent wasp sting. Among 41 patients with a mild European hornet sting SAR nobody reacted with an SSAR to a subsequent wasp sting. The association between the severity of the wasp SAR reaction in European hornet allergic patients was statistically significant (p=0.022). Conclusion: Our results suggest that patients with severe European hornet SAR should be considered for wasp venom immunotherapy or prophylactic prescription of epinephrine auto-injector as they are at risk for an SSAR also after wasp string.

Gingival hypersensitivity reactions to toothpastes: A case series and scoping review.

BACKGROUND: Hypersensitivity reactions to toothpastes are rare. The objective of this study was to present the authors' clinical cases in the past 10 years and perform a scoping review of gingival hypersensitivity responses to toothpastes. TYPES OF STUDIES REVIEWED: The authors reviewed records of documented gingival hypersensitivity reactions to dentifrices at the Postgraduate Clinic of Oral Medicine, Complutense University, Madrid, Spain, from January 2013 through December 2022. Furthermore, the authors conducted a search in PubMed with no date limit for articles reporting these hypersensitivity responses up through October 18, 2023. RESULTS: Eleven cases were collected from the clinic. Eight gingival hypersensitivity reactions occurred in women, and 6 were associated with cinnamon. The most frequent lesions diagnosed were red gingiva. The discontinuation of the toothpaste led to the disappearance of the lesions. The search yielded 643 references. Thirteen articles were included in the scoping review, all of them case series and case reports, reporting 32 cases. Lesions affected middle-aged women most frequently, the most common hypersensitivity reaction was gingival redness, and the cases implicated toothpastes containing cinnamon and herbal composition. PRACTICAL IMPLICATIONS: This study provides clues for diagnosing and treating hypersensitivity reactions to toothpastes, which may improve the identification, management, and reporting of these cases.

Immune and allergenic effects of the microalga Coccomyxa sp. strain KJ in healthy humans: A pilot study.

BACKGROUND: The Coccomyxa sp. strain KJ (Coccomyxa KJ), a microalga found in Japan, has a potential function in controlling viral infections. Recently, its dry powder has been marketed as a health food product. OBJECTIVES: This pilot study investigated the effects of Coccomyxa KJ powder tablet intake on allergic reactions and immune functions in healthy participants. MATERIAL AND METHODS: Nine healthy volunteers (4 males and 5 females) who expressed interest in foods containing Coccomyxa KJ, and were willing to undergo blood tests, were recruited. Each individual was asked to take 2 Coccomyxa KJ powder tablets (0.3 g) before breakfast once a day for 4 weeks. The salivary immunoglobulin A (IgA) level and blood parameters (white blood cell (WBC) count, eosinophil and lymphocyte counts and percentages, natural killer (NK) cell activity, interleukin (IL)-6 level, and T helper (Th)1/Th2 cell ratio) were evaluated at baseline and weeks 2 and 4. RESULTS: The 4-week intake of Coccomyxa KJ did not affect salivary IgA levels, WBC count, eosinophil and lymphocyte counts and percentages, or the Th1/Th2 ratio. There were significant differences in the NK cell activity after 4 weeks, with an average increase of 11.78 (95% confidence interval (95% CI): 6.80-16.76). None of the patients experienced adverse reactions during or after the study. CONCLUSIONS: Long-term Coccomyxa KJ intake improved NK cell activity without causing adverse effects on the indicators of local immunity, systemic inflammation and immune response balance. This study suggests that Coccomyxa KJ powder tablets can induce beneficial immune modifications without causing any adverse effects.

Fragrances as a trigger of immune responses in different environments.

Fragrances can cause allergic skin reactions, expressed as allergic contact dermatitis and reactions in the respiratory tract that range from acute temporary upper airway irritation to obstructive lung disease. These adverse health effects may result from the stimulation of a specific (adaptive) immune response. Th1 cells, which essentially produce interleukin-2 (IL-2) and interferon-γ (IFN-γ), play a key role in allergic contact dermatitis and also on allergic sensitization to common allergens (e.g., nickel and fragrance). It has been shown that fragrance allergy leads to Th2/Th22 production of IL-4, IL-5 and IL-13, controlling the development of IgE and mediating hypersensitivity reactions in the lung, such as asthma. Cytokines released during immune response modulate the expression of cytochrome P450 (CYPs) proteins, which can result in alterations of the pharmacological effects of substances in inflammatory diseases. The mechanisms linking environment and immunity are still not completely understood but it is known that aryl hydrocarbon receptor (AhR) is a sensor with conserved ligand-activated transcription factor, highly expressed in cells that controls complex transcriptional programs which are ligand and cell type specific, with CYPs as targeted genes. This review focuses on these important aspects of immune responses of the skin and respiratory tract cells, describing some in vitro models applied to evaluate the mechanisms involved in fragrance-induced allergy.