Prospective direct comparison of biologic treatments for severe eosinophilic asthma: Findings from the PRISM study.

BACKGROUND: Although various monoclonal antibodies have been used as add-on therapy for severe eosinophilic asthma (SEA), to the best of our knowledge, no direct head-to-head comparative study has evaluated their efficacy. OBJECTIVE: To compare the efficacy of reslizumab, mepolizumab, and dupilumab in patients with SEA. METHODS: This was a multicenter, prospective observational study in patients with SEA who had received 1 of these biologic agents for at least 6 months. Cox proportional hazard models were used to compare the risk of the first exacerbation event, adjusting for sputum or blood eosinophils and common asthma-related covariates. The annual exacerbation rate was analyzed using a negative binomial model, and a mixed-effect model was used to analyze changes in forced expiratory volume in 1 second and asthma control test score over time. RESULTS: A total of 141 patients with SEA were included in the analysis; 71 (50%) received dupilumab; 40 (28%) received reslizumab, and 30 (21%) received mepolizumab. During the 12-month follow-up, 27.5%, 43.3%, and 38.0% of patients in the reslizumab, mepolizumab, and dupilumab groups, respectively, experienced at least 1 exacerbation. However, after adjusting for confounding factors, the dupilumab and mepolizumab groups showed similar outcomes in time-to-first exacerbation, exacerbation rate, forced expiratory volume in 1 second, and asthma control test score to those of the reslizumab group. CONCLUSION: In patients with SEA, treatment with reslizumab, mepolizumab, and dupilumab resulted in comparable clinical outcomes within a 12-month period. TRIAL REGISTRATION: The cohort protocol was sanctioned by the Institutional Review Board of each study center (clinicaltrial.gov identifier NCT05164939).

Characterization of Codeine Treatment Responders Among Patients with Refractory or Unexplained Chronic Cough: A Prospective Real-World Cohort Study.

PURPOSE: Codeine is a narcotic antitussive often considered for managing patients with refractory or unexplained chronic cough. This study aimed to evaluate the proportion and characteristics of patients who responded to codeine treatment in real-world practice. METHODS: Data from the Korean Chronic Cough Registry, a multicenter prospective cohort study, were analyzed. Physicians assessed the response to codeine based on the timing and degree of improvement after treatment initiation. Follow-up assessments included the Leicester Cough Questionnaire and cough severity visual analog scale at six months. In a subset of subjects, objective cough frequency was evaluated following the initiation of codeine treatment. RESULTS: Of 305 patients, 124 (40.7%) responded to treatments based on anatomic diagnostic protocols, while 181 (59.3%) remained unexplained or refractory to etiological treatments. Fifty-one subjects (16.7%) were classified as codeine treatment responders (those showing a rapid and clear response), 57 (18.7%) as partial responders, and 62 (20.3%) as non-responders. Codeine responders showed rapid improvement in objective cough frequency and severity scores within a week of the treatment. At 6 months, responders showed significantly improved scores in cough scores, compared to non-responders. Several baseline parameters were associated with a more favorable treatment response, including older age, non-productive cough, and the absence of heartburn. CONCLUSIONS: Approximately 60% of chronic cough patients in specialist clinics may require antitussive drugs. While codeine benefits some, only a limited proportion (about 20%) of patients may experience rapid and significant improvement. This underscores the urgent need for new antitussive drugs to address these unmet clinical needs.

Predictors of Early and Late Lung Function Improvement in Severe Eosinophilic Asthma on Type2-Biologics in the PRISM Study.

BACKGROUND: The determinants linked to the short- and long-term improvement in lung function in patients with severe eosinophilic asthma (SEA) on biological treatment (BioT) remain elusive. OBJECTIVE: We sought to identify the predictors of early and late lung function improvement in patients with SEA after BioT. METHODS: 140 adult patients with SEA who received mepolizumab, dupilumab, or reslizumab were followed up for 6 months to evaluate improvement in forced expiratory volume in one second (FEV1). Logistic regression was used to determine the association between potential prognostic factors and improved lung function at 1 and 6 months of treatment. RESULTS: More than a third of patients with SEA using BioT showed early and sustained improvements in FEV1 after 1 month. A significant association was found between low baseline FEV1 and high blood eosinophil count and sustained FEV1 improvement after 1 month (0.54 [0.37-0.79] and 1.88 [1.28-2.97] odds ratios and 95% confidence interval, respectively). Meanwhile, among patients who did not experience FEV1 improvement after 1 month, 39% exhibited improvement at 6 months follow-up. A high ACT score measured at this visit was the most reliable predictor of late response after 6 months of treatment (OR and 95% CI 1.75 [1.09-2.98]). CONCLUSION: Factors predicting the efficacy of biological agents that improve lung function in SEA vary according to the stage of response.

Substitution with Low-Osmolar Iodinated Contrast Agent to Minimize Recurrent Immediate Hypersensitivity Reaction.

Background The recurrence of hypersensitivity reaction (HSR) to low-osmolar iodinated contrast media (LOCM) remains challenging despite premedication and substitution of the LOCM. Purpose To determine the optimal practical preventive strategy for LOCM substitution in patients with a history of prior immediate HSR to LOCM. Materials and Methods In a retrospective study, patients with an immediate HSR to LOCM before February 2020 and who underwent subsequent exposure to LOCM until March 2021 were enrolled in five tertiary referral hospitals in South Korea. The association of recurrence of an HSR after subsequent LOCM exposures was assessed using multivariate general estimating equation analysis according to age, sex, the severity of the index HSR, premedication, and substituting LOCM based on common carbamoyl side chains, including the N-(2,3-dihydroxypropyl)-carbamoyl and N-(2,3-dihydroxypropyl)-N-methyl-carbamoyl moieties. Results The evaluation included 3800 subsequent LOCM exposures in 1066 patients (mean age, 56.2 years ± 13.5 [SD]; 567 [53%] female and 499 [47%] male patients). The general estimating equation analysis, using 1:1 propensity score matched data for age, sex, HSR severity, and LOCM selection, showed that premedication with corticosteroids significantly reduced recurrent HSR (odds ratio [OR], 0.72; 95% CI: 0.52, 1.00; P = .049). The change to another LOCM with a common side chain had a similar recurrence rate as using the same LOCM (OR, 0.98; 95% CI: 0.64, 1.50; P = .93), whereas the use of a different LOCM without a common side chain significantly lowered HSR recurrence (OR, 0.51; 95% CI: 0.37, 0.69; P < .001) in multivariate general estimating equation analysis. Substitution of an LOCM without a common side chain was effective regardless of the index HSR severity but was more pronounced in moderate-to-severe reactions (OR, 0.30; 95% CI: 0.16, 0.55; P < .001). Conclusion For patients with a previous immediate HSR of any severity to LOCM, alternative LOCM without a common carbamoyl side chain reduced recurrent HSR during subsequent exposures. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by McDonald in this issue.

Adult asthma with symptomatic eosinophilic inflammation is accompanied by alteration in gut microbiome.

BACKGROUND: Accumulating evidence suggests that the gut microbiome is associated with asthma. However, altered gut microbiome in adult asthma is not yet well established. We aimed to investigate the gut microbiome profiles of adult asthmatic patients with symptomatic eosinophilic inflammation. METHODS: The 16 s rRNA gene metagenomic analysis of feces in the symptomatic eosinophilic asthma group (EA, n = 28) was compared with the healthy control (HC, n = 18) and the chronic cough control (CC, n = 13). A correlation analysis between individual taxa and clinical markers was performed within the EA group. Changes in the gut microbiome were examined in patients with significant symptom improvement in the EA group. RESULTS: The relative abundances of Lachnospiraceae and Oscillospiraceae significantly decreased and Bacteroidetes increased in the EA group. Within EA group, Lachnospiraceae was negatively correlated with indicators of type 2 inflammation and lung function decline. Enterobacteriaceae and Prevotella was positively associated with type 2 inflammation and lung function decline, respectively. The abundance of predicted genes associated with amino acid metabolism and secondary bile acid biosynthesis was diminished in the EA group. These functional gene family alterations could be related to gut permeability, and the serum lipopolysaccharide concentration was actually high in the EA group. EA patients with symptom improvement after 1 month did not show a significant change in the gut microbiome. CONCLUSIONS: Symptomatic eosinophilic adult asthma patients showed altered the gut microbiome composition. Specifically, a decrease in commensal clostridia was observed, and a decrease in Lachnospiraceae was correlated with blood eosinophilia and lung function decline.

WITHDRAWN: Prospective direct comparison of biological treatments on severe eosinophilic asthma: Findings from the PRISM study.

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Baseline Cohort Profile of the Korean Chronic Cough Registry: A Multicenter, Prospective, Observational Study.

PURPOSE: The Korean Chronic Cough Registry study was initiated to characterize patients with chronic cough (CC) and investigate their outcomes in real-world clinical practice. This report aims to describe the baseline cohort profile and study protocols. METHODS: This multicenter, prospective observational cohort study included newly referred CC patients and those already being treated for refractory or unexplained chronic cough (RUCC). Cough status was assessed using a visual analog scale, the Leicester Cough Questionnaire (LCQ), and the Cough Hypersensitivity Questionnaire (CHQ). RESULTS: A total of 610 patients (66.9% women; median age 59.0 years) were recruited from 18 centers, with 176 being RUCC patients (28.9%). The median age at CC onset was 50.1 years, and 94.4% had adult-onset CC (≥ 19 years). The median cough duration was 4 years. Compared to newly referred CC patients, RUCC patients had a longer cough duration (6.0 years vs. 3.0 years) but had fewer symptoms and signs suggesting asthma, rhinosinusitis, or gastroesophageal acid reflux disease. Subjects with RUCC had lower LCQ scores (10.3 ± 3.3 vs. 11.6 ± 3.6; P < 0.001) and higher CHQ scores (9.1 ± 3.9 vs. 8.4 ± 4.1; P = 0.024). There were no marked differences in the characteristics of cough between refractory chronic cough and unexplained chronic cough. CONCLUSIONS: Chronic cough typically develops in adulthood, lasting for years. Cough severity and quality of life impairment indicate the presence of unmet clinical needs and insufficient cough control in real-world clinical practice. Longitudinal follow-up is warranted to investigate the natural history and treatment outcomes.

Novel Therapeutic Effects of Pterosin B on Ang II-Induced Cardiomyocyte Hypertrophy.

Pathological cardiac hypertrophy is characterized by an abnormal increase in cardiac muscle mass in the left ventricle, resulting in cardiac dysfunction. Although various therapeutic approaches are being continuously developed for heart failure, several studies have suggested natural compounds as novel potential strategies. Considering relevant compounds, we investigated a new role for Pterosin B for which the potential life-affecting biological and therapeutic effects on cardiomyocyte hypertrophy are not fully known. Thus, we investigated whether Pterosin B can regulate cardiomyocyte hypertrophy induced by angiotensin II (Ang II) using H9c2 cells. The antihypertrophic effect of Pterosin B was evaluated, and the results showed that it reduced hypertrophy-related gene expression, cell size, and protein synthesis. In addition, upon Ang II stimulation, Pterosin B attenuated the activation and expression of major receptors, Ang II type 1 receptor and a receptor for advanced glycation end products, by inhibiting the phosphorylation of PKC-ERK-NF-κB pathway signaling molecules. In addition, Pterosin B showed the ability to reduce excessive intracellular reactive oxygen species, critical mediators for cardiac hypertrophy upon Ang II exposure, by regulating the expression levels of NAD(P)H oxidase 2/4. Our results demonstrate the protective role of Pterosin B in cardiomyocyte hypertrophy, suggesting it is a potential therapeutic candidate.

Age-related prevalence of chronic rhinosinusitis and nasal polyps and their relationships with asthma onset.

BACKGROUND: Chronic rhinosinusitis (CRS) is a major disease condition with high morbidity and can influence lower airway disease status in adults. However, its associations with adult asthma onset and activity have not been examined in detail in a general adult population. OBJECTIVE: To investigate relationships between CRS with nasal polyps (CRSwNP) and asthma characteristics. METHODS: A cross-sectional data set of 17,506 adult participants (≥18 years old) in the Korean National Health and Nutrition Examination Survey from 2010 through 2012 was analyzed. CRS was defined using structured questionnaires according to the international guideline, and presence of nasal polyps was objectively assessed using nasal endoscopy. Presence of asthma and its onset and current activity were assessed using structured questionnaires. RESULTS: CRS was significantly related to asthma, but the relationships were distinct by CRS and asthma status. CRSwNP was significantly associated with adult-onset asthma (onset after 18 years of age) or late-onset asthma (onset after 40 years of age), whereas CRS without nasal polyps was related to childhood-onset asthma (onset before 18 years) or early-onset asthma (onset before 40 years) in adults. The 2 CRS subgroups showed significant associations with current asthma but not with past asthma. However, the comorbid asthma rate was lower than 10% among subjects with CRS. CONCLUSION: This study found distinct age-related patterns of CRSwNP and asthma and demonstrated their significant associations in a general population. However, the low prevalence of asthma in CRSwNP is in sharp contrast to findings in Western populations, which warrants further investigation for ethnic or regional differences in relationships between CRSwNP and asthma.

Awareness and Acceptance of HIV Pre-exposure Prophylaxis among Medical Personnel and Men Who Have Sex with Men in Korea.

BACKGROUND: We aimed to investigate the awareness of human immunodeficiency virus (HIV) infection among high-risk individuals, including men who have sex with men (MSM) and medical personnel (MP) in Korea through a cross-sectional survey, identify possible obstacles hindering their access to pre-exposure prophylaxis (PrEP). METHODS: In 2016, the first questionnaire survey was sent to randomly selected MSM and MP. To compare the changes in attitudes and knowledge of MSM, a second questionnaire survey was conducted in August 2017. RESULTS: More than half of MSM (61.3% in 2016, 88.6% in 2017) were aware of PrEP. However, MP who offered PrEP had less knowledge regarding PrEP (23.4%). The background knowledge and experience with PrEP among MSM and MP in this survey was low (3.4% in 2016 and 5.7% in 2017, 1.9% in MP). The major obstacles that MSM reported were lack of insurance coverage (29% in 2016 and 32% in 2017), concern regarding adverse effects of PrEP (19% and 21%), and risk of exposing HIV-positive status to other people (15% and 18%). Among MP, lack of knowledge regarding the efficacy of PrEP was the most common obstacle (30%), followed by lack of insurance coverage (22%), and concern regarding adverse effects (20%). CONCLUSION: Our study showed that PrEP is required among MSM in Korea; however, most MP were not aware of PrEP. Lack of insurance coverage and knowledge regarding PrEP were major hindrances in the access to PrEP; therefore, further studies on how to make PrEP information more accessible are needed to help prevent HIV infection.

A New Scoring System for the Differential Diagnosis between Tuberculous Meningitis and Viral Meningitis.

BACKGROUND: Tuberculous meningitis (TBM) is associated with high mortality and morbidity despite administering anti-tuberculous chemotherapy to the patients. Differential diagnosis between TBM and viral meningitis (VM) is difficult in some clinical situations. METHODS: We reviewed and analyzed records of adult patients who were admitted and diagnosed with TBM or VM at a tertiary hospital in Korea, between January 2006 and December 2015. Diagnostic criteria for TBM were categorized into three groups: definite, probable, and possible TBM. The VM group included patients with no evidence of other meningitis who achieved complete recovery with only conservative treatments. Clinical, laboratory and radiological findings, as well as outcomes, were compared between the TBM and VM groups. RESULTS: Ninety-eight patients were enrolled. Among the study patients, 47 had TBM and 51 had VM. Based on univariate analysis and multivariate logistic regression, sodium < 135 mmol/L in serum (hyponatremia), lactate dehydrogenase > 70 (U/L) in cerebrospinal fluid (CSF), protein > 160 (mg/dL) in CSF, voiding difficulty, and symptoms of cranial nerve palsy were significant predictive factors for TBM in the final model. We constructed a weighted scoring system with predictive factors from multiple regression analyses. Receiver operating characteristic curve analyses and decision tree analyses were plotted to reveal an optimum cutoff point as 4 with this scoring system (range: 0-13). CONCLUSION: For differential diagnosis between TBM and VM, we created a new weighted scoring system. This scoring system and decision tree analysis are simple and easy to apply in clinical practice to differentiate TBM from VM.

Epidemiology of drug-induced anaphylaxis in a tertiary hospital in Korea.

BACKGROUND: Epidemiology and risk factors of drug-induced anaphylaxis are difficult to estimate due to lack of confirmative diagnosis and under reporting. Here we report the current state of drug-induced anaphylaxis in Korea based on an in-hospital pharmacovigilance database in a tertiary hospital. METHODS: This study is a retrospective analysis of drug-induced anaphylaxis, reported to an in-hospital pharmacovigilance center in Seoul National University Hospital from June 2009 to May 2013. Anaphylaxis occurred in patients under 18 years of age or developed by medications administered from outside pharmacies or hospitals were excluded. We assessed causative drug, incidence per use of each drug and risk factors of fatal anaphylactic shock. RESULTS: A total of 152 in-hospital drug-induced anaphylaxis cases were reported during the study period. The single most frequently reported drug was platinum compound and the incidence of anaphylaxis and anaphylactic shock in platinum compounds users was 2.84 and 1.39 per 1000 patients use. Risk factors of anaphylactic shock among total anaphylaxis cases were identified as older age ≥70 years [Odd's ratio (OR), 5.86; 95% confidence interval (CI), 1.70-20.14]. The use of iodinated contrast media (OR, 6.19; 95% CI, 1.87-20.53) and aminosteroid neuromuscular blocking agent (NMBA) (OR, 12.82; 95% CI, 1.50-109.92) were also a risk factor for the development of anaphylactic shock. CONCLUSIONS: Platinum compounds are the most commonly reported causative agents of in-hospital drug-induced anaphylaxis. Older age ≥70 years and drugs such as iodinated contrast media and aminosteroid NMBA are related with high risk of anaphylactic shock.

The HLA-A*2402/Cw*0102 haplotype is associated with lamotrigine-induced maculopapular eruption in the Korean population.

The use of lamotrigine (LTG) can be limited by the occurrence of cutaneous adverse drug reactions (cADRs) that range from maculopapular eruption (MPE) to the more severe Stevens-Johnson syndrome and toxic epidermal necrolysis. A few human leukocyte antigen (HLA)-related genetic risk factors for carbamazepine-induced cADR have been identified. However, the HLA-related genetic risk factors associated with LTG-induced cADR are not yet well known. We performed HLA genotyping in 50 Korean patients with epilepsy, including 21 patients presenting LTG-induced MPE and 29 LTG-tolerant patients. A significant association between the HLA-A*2402 allele and LTG-induced MPE was identified, in comparison with the LTG-tolerant group (odds ratio [OR] 4.09, p = 0.025) and the general Korean population (OR 3.949, p = 0.005). The frequencies of the Cw*0102 or Cw*0702 alleles were significantly higher in the LTG-MPE group than in the Korean population, whereas the frequency of the A*3303 allele was lower. The coexistence of the A*2402 and Cw*0102 alleles was significantly associated with the LTG-MPE group when compared to the LTG-tolerant group (OR 7.88, p = 0.007). In addition, the Cw*0701 allele was more frequent in the LTG-tolerant group than in the Korean population. These findings suggest the presence of HLA-related genetic risk factors for LTG-induced MPE in the Korean population.

Urban-rural differences in the prevalence of allergen sensitization and self-reported rhinitis in the elderly population.

BACKGROUND: Urbanization is frequently associated with allergic conditions during childhood; however, the literature lacks studies on the association between allergies and degree of urbanization in the elderly population. OBJECTIVE: To determine how the degree of urbanization affects the prevalence of allergic sensitization and self-reported rhinitis symptoms in elderly community populations. METHODS: The study population consisted of 1,311 elderly subjects identified from 2 community population cohort datasets who were divided into 3 groups according to the degree of urbanization (urban, semirural, and rural) where they resided. Current rhinitis symptoms were assessed using a questionnaire. Sensitization to inhalant allergen was measured using skin prick tests for 9 common allergens. RESULTS: Sensitization to inhalant allergen showed a positive correlation with degree of urbanization (urban 17.2%, semirural 9.8%, rural 6.0%; P for trend <.001), with a significant correlation observed between house dust mite allergens and degree of urbanization. Self-reported rhinitis symptoms were mostly nonallergic, but showed a positive correlation with degree of urbanization (urban 26.8%, semirural 18.2%, rural 11.5%; P for trend <.001). Self-reported rhinoconjunctivitis also correlated with urbanization. Correlations between self-reported allergic conditions and urbanization remained statistically significant in multivariate logistic regression tests. CONCLUSION: The present analyses found significant correlations between degree of urbanization with self-reported rhinitis symptoms and sensitization to inhalant allergen in the elderly population. These findings warrant further investigation of the roles that urban factors play in the development of elderly rhinitis and allergen sensitization.

Degenerative Calcification of Pericardial Bioprostheses: Comparison of Five Implantation Methods in a Rabbit Model.

BACKGROUND AND AIM OF THE STUDY: The degenerative calcification of bioprosthetic heart valves remains a clinical challenge, especially among young adults and children. Animal models that are based on subcutaneous and intramuscular implantation and are typically used to assess interventions to prevent bioprosthetic heart valve calcification do not reflect actual hemodynamic stress and lack direct blood contact. Thus, the study aim was to investigate bioprosthesis calcification at different implantation sites. METHODS: The calcification degrees of five valve implantation methods, namely subcutaneous, intramuscular and intravenous implantation, and arterial and venous patch angioplasty, were simultaneously investigated in 10 New Zealand White rabbits. RESULTS: Ultrasonography and computed tomography images showed vascular patency to be well maintained in all implanted vessels. Histologically, cellular infiltrates around the implant and within the collagen fibers were only found in the intravenous implantation group, which also had the highest calcium level among the methods. CONCLUSION: The present study was the first to compare the degree of calcification after applying five implantation methods simultaneously in one animal species. The rabbit intravenous implantation model, which involved direct contact with blood factors, is expected to serve as a useful animal model for research into the prevention of bioprosthetic heart valve degeneration.

Effectiveness of Carboplatin-Prescreening Intradermal Skin Tests to Reduce Unanticipated Immediate Hypersensitivity Reactions: A Comparative Study.

BACKGROUND: Carboplatin administration poses a risk of immediate hypersensitivity reactions (IHRs) that tend to increase with repeated administration and are mostly IgE-mediated. OBJECTIVE: This study evaluated the usefulness of carboplatin-prescreening intradermal skin tests (IDTs). METHODS: Carboplatin-prescreening IDTs were routinely conducted in patients with a history of receiving six or more carboplatin cycles beginning in January 2021. The primary objective was to assess disparities in the incidence of unanticipated IHRs to carboplatin administration. We compared patients in the intervention group (from 2021 to 2022) and those who did not undergo prescreening IDTs under the same conditions (preintervention group, from 2019 to 2020). Secondary objectives included evaluating the sensitivity and specificity of the prescreening IDT and the incidence of carboplatin IHR according to the number of infusion cycles. RESULTS: The intervention group was composed of 67 patients who were administered 347 carboplatin cycles whereas the preintervention group included 96 patients who were administered 464 carboplatin cycles. The risk of unanticipated carboplatin IHRs decreased by 83.2% in the intervention group compared with results in the preintervention group (preintervention group, 3.45%, n = 16 vs intervention group, 0.58%, n = 2; P = .005). The prescreening IDT showed a sensitivity and specificity of 77.78% and 99.41%, respectively. The risk of newly developed IHRs based on the number of carboplatin cycles was less than 1% (cycles 1-5), 2.11% (cycle 6), 3.90% (cycles 7-12), 2.90% (cycles 13-18), and 0.74% (cycles 19 and greater), respectively. CONCLUSIONS: Initiating carboplatin-prescreening IDTs from the seventh cycle on significantly reduced the risk of unanticipated IHRs.

Serum MRGPRX2 as a Long-term Biomarker for Iodinated Contrast Media-Induced Anaphylaxis.

The diagnosis of anaphylaxis is based on the clinical history. The utility of tryptase measurements in clinical setting is limited. Mas-related G protein-coupled receptor-X2 (MRGPRX2) is expressed in mast cells and is involved in the degranulation of these cells. We evaluated the potential of MRGPRX2 as a diagnostic biomarker in patients with iodinated contrast media (ICM)-induced immediate hypersensitivity reactions (IHRs). A total of 173 patients with documented ICM-induced IHR within 4 months from registration were enrolled and skin tests for the culprit ICM were performed. The time interval was evaluated as the duration between the onset of ICM-induced IHR and the measurement of serum MRGPRX2 levels. Serum MRGPRX2 concentration was determined using an enzyme-linked immunosorbent assay kit. Of the 173 patients, 33 and 140 were included in the anaphylaxis and non-anaphylaxis groups, respectively. Serum MRGPRX2 levels were significantly higher in the anaphylaxis than in the non-anaphylaxis group (29.9 ± 24.1 vs. 20.7±17.5, P = 0.044). Serum MRGPRX2 showed a moderate predictive ability for anaphylaxis, with an area under the curve of 0.61 (P = 0.058). When groups were classified based on the time interval, T1(0-2months) and T2 (2-4months), patients with anaphylaxis had higher MRGPRX2 levels compared to the non-anaphylaxis group in the T2 group (36.5±19.2 vs. 20.5±19.0, P = 0.035). This pilot study shows that serum MRGPRX2 is a potential long-term biomarker for predicting anaphylaxis, particularly ICM-induced anaphylaxis. Further studies are needed to determine the role of MRGPRX2 in anaphylaxis in a larger population of patients with various drug-induced IHRs.