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.

Cough Response to High-Dose Inhaled Corticosteroids in Patients with Chronic Cough and Fractional Exhaled Nitric Oxide Levels ≥ 25 ppb: A Prospective Study.

This study aimed to investigate the effects of high-dose inhaled corticosteroids (ICS) on chronic cough patients with elevated fractional exhaled nitric oxide (FeNO) levels. In a prospective study, adults with chronic cough and FeNO ≥ 25 ppb, without any other apparent etiology, received fluticasone furoate (200 mcg) for three weeks. Outcomes were evaluated using FeNO levels, cough severity, and Leicester Cough Questionnaire (LCQ) before and after treatment. Of the fifty participants (average age: 58.4 years; 58% female), the treatment responder rate (≥ 1.3-point increase in LCQ) was 68%, with a significant improvement in cough and LCQ scores and FeNO levels post-treatment. However, improvements in cough did not significantly correlate with changes in FeNO levels. These findings support the guideline recommendations for a short-term ICS trial in adults with chronic cough and elevated FeNO levels, but the lack of correlations between FeNO levels and cough raises questions about their direct mechanistic link.

HLA-DRB1 is associated with cefaclor-induced immediate hypersensitivity.

Background: Drug-induced hypersensitivity such as anaphylaxis is an important cause of drug-related morbidity and mortality. Cefaclor is a leading cause of drug induced type I hypersensitivity in Korea, but little is yet known about genetic biomarkers to predict this hypersensitivity reaction. We aimed to evaluate the possible involvement of genes in cefaclor induced type I hypersensitivity. Methods: Whole exome sequencing (WES) and HLA genotyping were performed in 43 patients with cefaclor induced type I hypersensitivity. In addition, homology modeling was performed to identify the binding forms of cefaclor to HLA site. Results: Anaphylaxis was the most common phenotype of cefaclor hypersensitivity (90.69%). WES results show that rs62242177 and rs62242178 located in LIMD1 region were genome-wide significant at the 5 × 10-8 significance level. Cefaclor induced type I hypersensitivity was significantly associated with HLA-DRB1∗04:03 (OR 4.61 [95% CI 1.51-14.09], P < 0.002) and HLA-DRB1∗14:54 (OR 3.86 [95% CI 1.09-13.67], P < 0.002). Conclusion: LIMD1, HLA-DRB1∗04:03 and HLA-DRB1∗14:54 may affect susceptibility to cefaclor induced type I hypersensitivity. Further confirmative studies with a larger patient population should be performed to ascertain the role of HLA-DRB1 and LIMD1 in the development of cefaclor induced hypersensitivity.

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.

Safety, Tolerability, Pharmacokinetics, and pharmacodynamics of YH35324, a novel Long-Acting High-Affinity IgETrap-Fc protein in subjects with Atopy: Results from the First-in-Human study.

BACKGROUND: YH35324, a long-acting IgETrap-Fc fusion protein, is a novel therapeutic agent for immunoglobulin E (IgE)-mediated allergic diseases. This randomized, double-blind, placebo/active-controlled, single ascending dose Phase 1 study assessed the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of YH35324 in subjects with atopy. METHODS: Eligible subjects were healthy subjects or atopic adults with mild allergic rhinitis, atopic dermatitis, food allergy, or urticaria, and a serum total IgE level of 30-700 IU/mL (Part A) or > 700 IU/mL (Part B). In Part A, 35 subjects in 5 cohorts received YH35324 (0.3, 1, 3, 6, and 9 mg/kg), 8 received omalizumab (300 mg), and 9 received placebo. In Part B, 8 subjects received YH35324 and 8 received omalizumab. RESULTS: Twenty subjects (38.5 %) in Part A (YH35324: 37.1 %, omalizumab: 50.0 %, placebo: 33.3 %) and 10 subjects (62.5 %) in Part B (YH35324: 100 %; omalizumab: 25.0 %) experienced treatment-emergent adverse events (TEAEs). TEAEs were mostly grade 1/2; no serious AEs, AE-related treatment discontinuation, or anaphylaxis were reported. YH35324 exhibited dose-proportional increase in Cmax and AUClast over the dose range of 0.3-9 mg/kg. YH35324 rapidly suppressed serum-free IgE levels to a significant extent (< 25 and < 82.8 ng/mL, both P < 0.05) and with longer duration than omalizumab. CONCLUSION: This study showed that YH35324 has a favorable safety profile and is effective in reducing serum-free IgE levels in subjects with atopic conditions.

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.

MetaLAB-HOI: Template standardization of health outcomes enable massive and accurate detection of adverse drug reactions from electronic health records.

PURPOSE: This study aimed to advance the MetaLAB algorithm and verify its performance with multicenter data to effectively detect major adverse drug reactions (ADRs), including drug-induced liver injury. METHODS: Based on MetaLAB, we created an optimal scenario for detecting ADRs by considering demographic and clinical records. MetaLAB-HOI was developed to identify ADR signals using common model-based multicenter electronic health record (EHR) data from the clinical health outcomes of interest (HOI) template and design for drug-exposed and nonexposed groups. In this study, we calculated the odds ratio of 101 drugs for HOI in Konyang University Hospital, Seoul National University Hospital, Chungbuk National University Hospital, and Seoul National University Bundang Hospital. RESULTS: The overlapping drugs in four medical centers are amlodipine, aspirin, bisoprolol, carvedilol, clopidogrel, clozapine, digoxin, diltiazem, methotrexate, and rosuvastatin. We developed MetaLAB-HOI, an algorithm that can detect ADRs more efficiently using EHR. We compared the detection results of four medical centers, with drug-induced liver injuries as representative ADRs. CONCLUSIONS: MetaLAB-HOI's strength lies in fully utilizing the patient's clinical information, such as prescription, procedure, and laboratory results, to detect ADR signals. Considering changes in the patient's condition over time, we created an algorithm based on a scenario that accounted for each drug exposure and onset period supervised by specialists for HOI. We determined that when a template capable of detecting ADR based on clinical evidence is developed and manualized, it can be applied in medical centers for new drugs with insufficient data.

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).

Eosinophilic Granulomatosis With Polyangiitis Following COVID-19 Vaccination: A Case Report.

The current emergence of the coronavirus disease 2019 (COVID-19) pandemic and the possible side effects of COVID-19 mRNA vaccination remain worrisome. Few cases of vaccination-related side effects, such as vasculitis, have been reported. Eosinophilic granulomatosis with polyangiitis (EGPA), also known as Churg-Strauss syndrome, is a type of vasculitis characterized by the histological richness of eosinophils, asthma, polyneuropathy, sinusitis, and skin or lung involvement. Here, we report the first case of new onset EGPA following COVID-19 vaccination in Korea. A 71-year old woman developed a skin rash and presented with progressive weakness of the upper and lower extremities after the BNT162b2 vaccination (Pfizer-BioNTech). She was diagnosed with EGPA and her symptoms improved after systemic steroid and immunosuppressant therapy. Although it is very rare, clinicians should be aware that EGPA may occur after COVID-19 vaccination.

A comparison of treatment response to biologics in asthma-COPD overlap and pure asthma: Findings from the PRISM study.

Background: Despite the increasing use of biologics in severe asthma, there is limited research on their use in asthma-chronic obstructive pulmonary disease overlap (ACO). We compared real-world treatment responses to biologics in ACO and asthma. Methods: We conducted a multicenter, retrospective, cohort study using data from the Precision Medicine Intervention in Severe Asthma (PRISM). ACO was defined as post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.7 and a smoking history of >10 pack-years. Physicians selected biologics (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) based on each United States Food & Drug Administration (FDA) approval criteria. Results: After six-month treatment with biologics, both patients with ACO (N = 13) and asthma (N = 81) showed positive responses in FEV1 (10.69 ± 17.17 vs. 11.25 ± 12.87 %, P = 0.652), Asthma Control Test score (3.33 ± 5.47 vs. 5.39 ± 5.42, P = 0.290), oral corticosteroid use (-117.50 ± 94.38 vs. -115.06 ± 456.85 mg, P = 0.688), fractional exhaled nitric oxide levels (-18.62 ± 24.68 vs. -14.66 ± 45.35 ppb, P = 0.415), sputum eosinophils (-3.40 ± 10.60 vs. -14.48 ± 24.01 %, P = 0.065), blood eosinophils (-36.47 ± 517.02 vs. -363.22 ± 1294.59, P = 0.013), and exacerbation frequency (-3.07 ± 4.42 vs. -3.19 ± 5.11, P = 0.943). The odds ratio for exacerbation and time-to-first exacerbation showed no significant difference after full adjustments, and subgroup analysis according to biologic type was also showed similar results. Conclusions: Biologics treatment response patterns in patients with ACO and asthma were comparable, suggesting that biologics should be actively considered for ACO patients as well.

Epithelial Barrier Theory: The Role of Exposome, Microbiome, and Barrier Function in Allergic Diseases.

Allergic diseases are a major public health problem with increasing prevalence. These immune-mediated diseases are characterized by defective epithelial barriers, which are explained by the epithelial barrier theory and continuously emerging evidence. Environmental exposures (exposome) including global warming, changes and loss of biodiversity, pollution, pathogens, allergens and mites, laundry and dishwasher detergents, surfactants, shampoos, body cleaners and household cleaners, microplastics, nanoparticles, toothpaste, enzymes and emulsifiers in processed foods, and dietary habits are responsible for the mucosal and skin barrier disruption. Exposure to barrier-damaging agents causes epithelial cell injury and barrier damage, colonization of opportunistic pathogens, loss of commensal bacteria, decreased microbiota diversity, bacterial translocation, allergic sensitization, and inflammation in the periepithelial area. Here, we review scientific evidence on the environmental components that impact epithelial barriers and microbiome composition and their influence on asthma and allergic diseases. We also discuss the historical overview of allergic diseases and the evolution of the hygiene hypothesis with theoretical evidence.

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.

A smartphone-based application for cough counting in patients with acute asthma exacerbation.

Background: While tools exist for objective cough counting in clinical studies, there is no available tool for objective cough measurement in clinical practice. An artificial intelligence (AI)-based cough count system was recently developed that quantifies cough sounds collected through a smartphone application. In this prospective study, this AI-based cough algorithm was applied among real-world patients with an acute exacerbation of asthma. Methods: Patients with an acute asthma exacerbation recorded their cough sounds for 7 days (2 consecutive hours during awake time and 5 consecutive hours during sleep) using CoughyTM smartphone application. During the study period, subjects received systemic corticosteroids and bronchodilator to control asthma. Coughs collected by application were counted by both the AI algorithm and two human experts. Subjects also provided self-measured peak expiratory flow rate (PEFR) and completed other outcome assessments [e.g., cough symptom visual analogue scale (CS-VAS), awake frequency, salbutamol use] to investigate the correlation between cough and other parameters. Results: A total of 1,417.6 h of cough recordings were obtained from 24 asthmatics (median age =39 years). Cough counts by AI were strongly correlated with manual cough counts during sleep time (rho =0.908, P<0.001) and awake time (rho =0.847, P<0.001). Sleep time cough counts were moderately to strongly correlated with CS-VAS (rho =0.339, P<0.001), the frequency of waking up (rho =0.462, P<0.001), and salbutamol use at night (rho =0.243, P<0.001). Weak-to-moderate correlations were found between awake time cough counts and CS-VAS (rho =0.313, P<0.001), the degree of activity limitation (rho =0.169, P=0.005), and salbutamol use at awake time (rho =0.276, P<0.001). Neither awake time nor sleep time cough counts were significantly correlated with PEFR. Conclusions: The strong correlation between cough counts using the AI-based algorithm and human experts, and other indicators of patient health status provides evidence of the validity of this AI algorithm for use in asthma patients experiencing an acute exacerbation. Study findings suggest that CoughyTM could be a novel solution for objectively monitoring cough in a clinical setting.

Skin Test-Guided Strategy to Select Alternative Iodinated Contrast Media in Patients With Immediate Hypersensitivity Reaction: A Prospective Confirmative Study.

BACKGROUND: Iodinated contrast media (ICM) are a common cause of drug-induced immediate hypersensitivity reaction (IHR). Repeated use of ICM is often necessary; therefore, a standardized protocol to prevent recurrence of IHR is required. OBJECTIVE: We aimed to propose an intradermal skin test (IDT)-guided strategy for previous reactors to prevent recurrence of IHR. METHODS: We conducted a prospective multicenter study from May 2018 to December 2020 and recruited patients who had experienced IHR to ICM. Once enrolled, the participants underwent IDT with a causative ICM. The alternatives for reexposure were selected using the following protocol: (1) if the IDT with the culprit ICM was positive, further skin tests with other available ICM were conducted to choose IDT-negative agents as alternatives, and (2) if the IDT with the culprit ICM was negative, a randomly changed ICM was used without additional skin tests. The recurrence and severity of hypersensitivity were assessed in subsequent computed tomography examinations. Premedication was administered according to the severity of the index event in all cases. RESULTS: A total of 496 participants were enrolled, and 299 were reexposed to ICM. Among 269 participants who followed the protocol, 228 (84.8%) completed computed tomography examinations without adverse reactions, and IHR recurred in 16 of 30 participants (53.3%) who did not follow the protocol (P < .001). In addition, application of the protocol reduced the severity of IHR in recurred cases (P = 0.003). CONCLUSIONS: Our IDT-guided strategy not only reduced recurrence of IHR to ICM but also mitigated the severity in recurred cases. This provides evidence for recommending an IDT to diagnose ICM allergy and find safe alternatives.

Bronchial epithelial cells release inflammatory markers linked to airway inflammation and remodeling in response to TLR5 ligand flagellin.

Background/Aims: Flagellin, which is abundant in gram-negative bacteria, including Pseudomonas, is reported to influence on inflammatory responses in various lung diseases. However, its effect on airway epithelial cells in contribution to asthma pathogenesis is not elucidated yet. We aimed to investigate the effect of TLR5 ligand flagellin on the transcriptomic profile of primary human epithelial cells and to determine the markers of airway inflammation. Methods: Normal human bronchial epithelial (NHBE) cells were grown and differentiated in air-liquid interface (ALI) culture for 14-16 days. The cells were treated with flagellin in vitro at 10 and 100 ng/ml for 3 and 24 h. The conditioned media and cells were harvested to validate inflammatory markers involved in airway inflammation using ELISA, Western blot, and quantitative PCR methods. RNA-sequencing was performed to investigate the transcriptional response to flagellin in ALI-NHBE cells. Results: Altered transcriptional responses to flagellin in differentiated bronchial epithelial cells were determined, including genes encoding chemokines, matrix metalloproteinases, and antimicrobial biomolecules. Pathway analysis of the transcriptionally responsive genes revealed enrichment of signaling pathways. Flagellin induced the mRNA expressions of proinflammatory cytokines and chemokines, and secretion of GM-CSF, CXCL5, CCL5 and CXCL10. Flagellin enhanced the protein expression of MMP-13 in TGF-ß1 and TGF-ß2 pretreated cell lysates and Wnt/ß-catenin signaling. Conclusions: These findings suggest that flagellin could be a potent inducer of inflammatory markers that may contribute to airway inflammation and remodeling.

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

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Exercise With a Novel Digital Device Increased Serum Anti-influenza Antibody Titers After Influenza Vaccination.

It has been reported that some exercise could enhance the anti-viral antibody titers after vaccination including influenza and coronavirus disease 2019 vaccines. We developed SAT-008, a novel digital device, consists of physical activities and activities related to the autonomic nervous system. We assessed the feasibility of SAT-008 to boost host immunity after an influenza vaccination by a randomized, open-label, and controlled study on adults administered influenza vaccines in the previous year. Among 32 participants, the SAT-008 showed a significant increase in the anti-influenza antibody titers assessed by hemagglutination-inhibition test against antigen subtype B Yamagata lineage after 4 wk of vaccination and subtype B Victoria lineage after 12 wk (p<0.05). There was no difference in the antibody titers against subtype "A." The SAT-008 also showed significant increase in the plasma cytokine levels of IL-10, IL-1ß, and IL-6 at weeks 4 and 12 after the vaccination (p<0.05). A new approach using the digital device may boost host immunity against virus via vaccine adjuvant-like effects. Trial Registration: ClinicalTrials.gov Identifier: NCT04916145.

Development and Application of an Active Pharmacovigilance Framework Based on Electronic Healthcare Records from Multiple Centers in Korea.

INTRODUCTION: With the availability of retrospective pharmacovigilance data, the common data model (CDM) has been identified as an efficient approach towards anonymized multicenter analysis; however, the establishment of a suitable model for individual medical systems and applications supporting their analysis is a challenge. OBJECTIVE: The aim of this study was to construct a specialized Korean CDM (K-CDM) for pharmacovigilance systems based on a clinical scenario to detect adverse drug reactions (ADRs). METHODS: De-identified patient records (n = 5,402,129) from 13 institutions were converted to the K-CDM. From 2005 to 2017, 37,698,535 visits, 39,910,849 conditions, 259,594,727 drug exposures, and 30,176,929 procedures were recorded. The K-CDM, which comprises three layers, is compatible with existing models and is potentially adaptable to extended clinical research. Local codes for electronic medical records (EMRs), including diagnosis, drug prescriptions, and procedures, were mapped using standard vocabulary. Distributed queries based on clinical scenarios were developed and applied to K-CDM through decentralized or distributed networks. RESULTS: Meta-analysis of drug relative risk ratios from ten institutions revealed that non-steroidal anti-inflammatory drugs (NSAIDs) increased the risk of gastrointestinal hemorrhage by twofold compared with aspirin, and non-vitamin K anticoagulants decreased cerebrovascular bleeding risk by 0.18-fold compared with warfarin. CONCLUSION: These results are similar to those from previous studies and are conducive for new research, thereby demonstrating the feasibility of K-CDM for pharmacovigilance. However, the low quality of original EMR data, incomplete mapping, and heterogeneity between institutions reduced the validity of the analysis, thus necessitating continuous calibration among researchers, clinicians, and the government.

Bacterial Etiology in Subacute Cough.

Although postinfectious etiology is the most common cause of subacute cough, there are insufficient data on the epidemiology of associated bacterial infections. We aimed to identify the etiology of bacterial detection in subjects with subacute cough. A multicenter prospective observational study of 142 patients with postinfectious subacute cough was performed between August 2016 and December 2017 in Korea. We obtained 2 nasal swabs from each patient and used a multiplex bacterial polymerase chain reaction (PCR) kit that simultaneously detects Bordetella pertussis, Chlamydophila pneumoniae, Haemophilus influenzae, Legionella pneumophilia, Mycoplasma pneumoniae, and Streptococcus pneumoniae. About 29% (n = 41) of patients with subacute cough were positive for bacterial PCR in nasal swabs. The most common bacteria detected by bacterial PCR was H. influenzae (n = 19, 13.4%), followed by S. pneumoniae (n = 18, 12.7%), B. pertussis (n = 7, 4.9%), M. pneumoniae (n = 3, 2.1%), L. pneumophilia (n = 2, 1.4%), and C. pneumoniae (n = 1, 0.7%). Nine patients had dual positivity for the PCR. In conclusion, bacterial PCR was positive in the nasal swabs of about 29% of subjects with subacute cough, including 5% of positive PCR results for B. pertussis.