Incidence and Economic Burden of Adverse Drug Reactions in Hospitalization: A Prospective Study in Korea

Background@#Adverse drug reactions (ADRs) are escalating, and their socioeconomic burden is increasing. However, large-scale prospective studies investigating ADRs during hospitalization are rare in Korea. We prospectively investigated the incidence, characteristics, and economic burden of ADRs in hospitalized patients based on electronic medical records (EMRs). @*Methods@#Among patients admitted to three hospitals from October 2016 to October 2017, 5,000 patients were randomly selected and prospectively observed during hospitalization.Research nurses monitored and detected patients who had symptoms, signs, or laboratory findings suspicious for ADRs using an EMR-based detection protocol. Next, allergy and ADR specialists reviewed the medical records to determine the relationship between adverse reactions and drugs. Cases in which a causal relationship was certain, probable/likely, or possible were included in the ADR cases. Clinically meaningful ADR cases or those leading to prolonged hospitalization were defined as significant ADRs. @*Results@#ADRs occurred in 510 (10.2%) patients. The mean length of hospital stay was approximately 5 days longer in patients with ADRs. Opioids accounted for the highest percentage of total ADRs. Significant ADRs were observed in 148 (3.0%) patients. Antibiotics accounted for the highest percentage of significant ADRs. Drug hypersensitivity reactions (DHRs) occurred in 88 (1.8%) patients. Antibiotics accounted for the highest percentage of DHRs. The average medical expenses for one day of hospitalization per patient were highest in significant ADRs, followed by non-significant ADRs, and non-ADRs. @*Conclusion@#ADRs in hospitalized patients are an important clinical issue, resulting in a substantial socioeconomic burden. EMR-based strategy could be a useful tool for ADR monitoring and early detection.

Comparison of Two pMDIs in Adult Asthmatics: A Randomized Double-Blind Double-Dummy Clinical Trial / 결핵및호흡기질환

Background@#Only a few studies directly compared the therapeutic efficacy and safety of two pressurized metered-dose inhalers (pMDIs) in asthma. We analyzed the asthma treatment outcomes, safety, and patient preferences using formoterol/beclomethasone (FORM/BDP), a pMDI with extra-fine particles, compared with formoterol/budesonide (FORM/BUD), another pMDI with non-extra-fine particles. @*Methods@#In this randomized, double-blind, double-dummy parallel group study, 40 adult asthmatics were randomized to FORM/BDP group (n=18; active FORM/BDP and placebo FORM/BUD) or FORM/BUD group (n=22; active FORM/BUD and placebo FORM/BDP). During the two visits (baseline and end of 8-week treatment), subjects were asked to answer questionnaires including asthma control test (ACT), asthma control questionnaires (ACQ), and Quality of Life Questionnaire for Adult Korean Asthmatics (QLQAKA). Lung function, compliance with inhaler, and inhaler-handling skills were also assessed. @*Results@#Ten subjects in the FORM/BDP group and 14 in the FORM/BUD group completed follow-up visits. ACT, ACQ, QLQAKA (a primary outcome), and adverse events did not differ between two groups. We found that the increase in forced expiratory volume in 1 second/forced vital capacity and forced expiratory flow at 25% to 75% of the pulmonary volume in the FORM/BDP group was higher than in the FORM/BUD group. Regarding preference, subjects responded that the flume velocity of FORM/BDP was higher, but more adequate than that of FORM/BUD. They also answered that FORM/BDP reached the trachea and bronchus and irritated them significantly more than FORM/BUD. @*Conclusion@#The use of pMDI with extra-fine particles may relieve small airway obstruction more than the one with non-extra-fine particles despite no significant differences in overall treatment outcomes. Some asthmatics have a misconception about the adequacy of high flume velocity of pMDIs.

Korean Clinical Practice Guidelines for Adverse Reactions to Intravenous Iodinate and MRI-Gadolinium Contrast Agents: Revised Clinical Consensus and Recommendations (3rd Edition, 2022)

The Korean Society of Radiology and Medical Guidelines Committee amended the existing 2016 guidelines to publish the “Korean Clinical Practice Guidelines for Adverse Reactions to Iodide Contrast for Injection and Gadolinium Contrast for MRI: The Revised Clinical Consensus and Recommendations (2022 Third Edition).” Expert members recommended and approved by the Korean Society of Radiology, the Korean Academy of Asthma, Allergy and Clinical Immunology, and the Korean Nephrology Society participated together. According to the expert consensus or systematic literature review, the description of the autoinjector and connection line for the infection control while using contrast medium, the acute adverse reaction, and renal toxicity to iodized contrast medium were modified and added. We would like to introduce the revised contents.

A Case Report of Thrombotic Thrombocytopenia After ChAdOx1 nCov-19 Vaccination and Heparin Use During Hemodialysis

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but life-threatening complication. VITT strongly mimics heparin-induced thrombocytopenia (HIT) and shares clinical features. Heparin is commonly used to prevent coagulation during hemodialysis.Therefore, nephrologists might encounter patients needing dialysis with a history of heparin exposure who developed thrombotic thrombocytopenia after vaccination. A 70-year-old male presented with acute kidney injury and altered mental status due to lithium intoxication. He needed consecutive hemodialysis using heparin. Deep vein thrombosis of left lower extremity and accompanying severe thrombocytopenia of 15,000/µL on 24 days after vaccination and at the same time, nine days after heparin use. Anti-platelet factor 4 antibody test was positive.Anticoagulation with apixaban and intravenous immunoglobulin (IVIG) infusion resolved swelling of his left calf and thrombocytopenia. There were no definitive diagnostic tools capable of differentiating between VITT and HIT in this patient. Although VITT and HIT share treatment with IVIG and non-heparin anticoagulation, distinguishing between VITT and HIT will make it possible to establish a follow-up vaccination plan in a person who has had a thrombocytopenic thrombotic event. Further research is needed to develop the tools to make a clear distinction between the clinical syndromes.

Soluble ACE2 and TMPRSS2 Levels in the Serum of Asthmatic Patients

Background@#Angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2) are key proteins mediating viral entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although gene expressions of ACE2 and TMPRSS2 have been analyzed in various organs and diseases, their soluble forms have been less studied, particularly in asthma. Therefore, we aimed to measure circulating ACE2 and TMPRSS2 in the serum of asthmatics and examine their relationship with clinical characteristics. @*Methods@#Clinical data and serum samples of 400 participants were obtained from an asthma cohort. The soluble ACE2 (sACE2) and soluble TMPRSS2 (sTMPRSS2) level was measured by enzyme-linked immunosorbent assay, and the values underwent a natural log transformation. Associations between sACE2 and TMPRSS2 levels and various clinical variables were analyzed. @*Results@#The patients younger than 70 years old, those with eosinophilic asthma (eosinophils ≥ 200 cells/µL), and inhaled corticosteroids (ICS) non-users were associated with higher levels of sACE2. Blood eosinophils and fractionated exhaled nitric oxide levels were positively correlated with serum ACE2. In contrast, lower levels of sTMPRSS2 were noted in patients below 70 years and those with eosinophilic asthma, while no association was noted between ICS use and sTMPRSS2. The level of sTMPRSS2 also differed according to sex, smoking history, coexisting hypertension, and forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) ratio. The proportion of sputum neutrophils was positively correlated with sTMPRSS2, while the FEV1/FVC ratio reported a negative correlation with sTMPRSS2. @*Conclusion@#The levels of ACE2 and TMPRSS2 were differently expressed according to age, ICS use, and several inflammatory markers. These findings suggest variable susceptibility and prognosis of SARS-CoV-2 infection among asthmatic patients.

Association Between Clinical Burden and Blood Eosinophil Counts in Asthma: Findings From a Korean Adult Asthma Cohort

Background@#Some reports have suggested that the clinical and economic burdens of asthma are associated with blood eosinophil levels. The association between clinical burden and blood eosinophil counts were evaluated in a Korean adult asthma cohort. @*Methods@#Clinical information including blood eosinophil counts that were not affected by systemic corticosteroids were extracted from the Cohort for Reality and Evolution of Adult Asthma in Korea database. Clinical burden was defined as 1) asthma control status, 2) medication demand and 3) acute exacerbation (AE) events during 1 consecutive year after enrollment. All patients were divided into atopic and non-atopic asthmatics. The associations between asthma outcomes and the blood eosinophil count were evaluated. @*Results@#In total, 302 patients (124 atopic and 178 non-atopic asthmatics) were enrolled. In all asthmatics, the risk of severe AE was higher in patients with blood eosinophil levels < 100 cells/µL than in patients with levels ≥ 100 cells/µL (odds ratio [OR], 5.406; 95% confidence interval [CI], 1.266–23.078; adjusted P = 0.023). Among atopic asthmatics, the risk of moderate AE was higher in patients with blood eosinophil levels ≥ 300 cells/µL than in patients with levels < 300 cells/µL (OR, 3.558; 95% CI, 1.083–11.686; adjusted P = 0.036). Among non-atopic asthmatics, the risk of medication of Global Initiative for Asthma (GINA) steps 4 or 5 was higher in patients with high blood eosinophil levels than in patients with low blood eosinophil levels at cutoffs of 100, 200, 300, 400, and 500 cells/µL. @*Conclusion@#The baseline blood eosinophil count may predict the future clinical burden of asthma.

Adverse Reactions of the Second Dose of the BNT162b2 mRNA COVID-19Vaccine in Healthcare Workers in Korea

We conducted a prospective, mobile-based survey on the self-reported adverse reactions in healthcare workers (HCWs) who received both doses of the BNT162b2 mRNA vaccine. Of the 342 HCWs who completed the two-dose vaccination, 265 (77.5%) responded to the survey at least once. Overall, the rates of adverse reactions were higher after the second dose compared with the first dose (89.1% vs. 80.1%, P = 0.006). The most common systemic reactions were muscle ache (69.1%), fatigue (65.7%), headache (48.7%), chills (44.2%), and fever (32.1%), and were notably more common after the second dose vaccine as well. We also noted a sex difference in which the frequency of adverse reactions after the second dose of the vaccine was significantly higher in females, which was not observed after the first dose. The rates of adverse reactions were lower in older age groups, and the rates and severities of the adverse reactions decreased during the 3-day period following vaccination.

Adverse Reactions Following the First Dose of ChAdOx1 nCoV-19 Vaccine and BNT162b2 Vaccine for Healthcare Workers in South Korea

Background@#We performed a prospective survey on the adverse reactions following the first dose of two types of vaccines against coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs) in South Korea. @*Methods@#HCWs at a tertiary referral hospital in Seoul, South Korea, received a chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19) or an mRNA-based vaccine (BNT162b2) between March 5 and March 26, 2021. The HCWs were asked to report adverse reactions through a mobile self-report questionnaire for three days after vaccination. @*Results@#A total of 7,625 HCWs received the first dose of ChAdOx1 or BNT162b2 vaccine during the study period. Of them, 5,866 (76.9%) HCWs (ChAdOx1, n = 5,589 [95.3%];BNT162b2, n = 277 [4.7%]) participated at least once in the survey, of whom 77% were female and 86% were younger than 50 years. The overall adverse reaction rate was 93% in the ChAdOx1 group and 80% in the BNT162b2 group (P < 0.001). Both local and systemic reactions were more commonly reported in the ChAdOx1 group, and the difference was larger in systemic reactions such as fever and fatigue. In the ChAdOx1 group, the incidence of adverse reactions was significantly higher in females and those in the younger age groups, while the BNT162b2 group showed such difference according to age. @*Conclusion@#In our prospective survey, vaccine-associated adverse reactions were more commonly reported in the ChAdOx1 group than in the BNT162b2 group. Females and younger age groups experienced vaccine-associated adverse reactions more frequently.

Adverse Reactions of the Second Dose of the BNT162b2 mRNA COVID-19Vaccine in Healthcare Workers in Korea

We conducted a prospective, mobile-based survey on the self-reported adverse reactions in healthcare workers (HCWs) who received both doses of the BNT162b2 mRNA vaccine. Of the 342 HCWs who completed the two-dose vaccination, 265 (77.5%) responded to the survey at least once. Overall, the rates of adverse reactions were higher after the second dose compared with the first dose (89.1% vs. 80.1%, P = 0.006). The most common systemic reactions were muscle ache (69.1%), fatigue (65.7%), headache (48.7%), chills (44.2%), and fever (32.1%), and were notably more common after the second dose vaccine as well. We also noted a sex difference in which the frequency of adverse reactions after the second dose of the vaccine was significantly higher in females, which was not observed after the first dose. The rates of adverse reactions were lower in older age groups, and the rates and severities of the adverse reactions decreased during the 3-day period following vaccination.

Adverse Reactions Following the First Dose of ChAdOx1 nCoV-19 Vaccine and BNT162b2 Vaccine for Healthcare Workers in South Korea

Background@#We performed a prospective survey on the adverse reactions following the first dose of two types of vaccines against coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs) in South Korea. @*Methods@#HCWs at a tertiary referral hospital in Seoul, South Korea, received a chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19) or an mRNA-based vaccine (BNT162b2) between March 5 and March 26, 2021. The HCWs were asked to report adverse reactions through a mobile self-report questionnaire for three days after vaccination. @*Results@#A total of 7,625 HCWs received the first dose of ChAdOx1 or BNT162b2 vaccine during the study period. Of them, 5,866 (76.9%) HCWs (ChAdOx1, n = 5,589 [95.3%];BNT162b2, n = 277 [4.7%]) participated at least once in the survey, of whom 77% were female and 86% were younger than 50 years. The overall adverse reaction rate was 93% in the ChAdOx1 group and 80% in the BNT162b2 group (P < 0.001). Both local and systemic reactions were more commonly reported in the ChAdOx1 group, and the difference was larger in systemic reactions such as fever and fatigue. In the ChAdOx1 group, the incidence of adverse reactions was significantly higher in females and those in the younger age groups, while the BNT162b2 group showed such difference according to age. @*Conclusion@#In our prospective survey, vaccine-associated adverse reactions were more commonly reported in the ChAdOx1 group than in the BNT162b2 group. Females and younger age groups experienced vaccine-associated adverse reactions more frequently.

Prescreening skin test effectiveness in predicting hypersensitivity to iodinated contrast media

Hypersensitivity reaction to iodinated contrast media (ICM) is a persistent clinical issue owing to widespread use of computed tomography (CT) examinations. The question of whether routine performance of skin tests can predict hypersensitivity reactions to contrast media remains unresolved. Recently, a prospective study was performed to evaluate the role of an intradermal skin test as a prescreening test for hypersensitivity reactions to ICM. Fifteen (0.5%) of the 2,843 patients had positive skin test results prior to scheduled CT scans. However, none of the patients experienced a hypersensitivity reaction after administration of full-dose ICM. Meanwhile, 19 patients who experienced hypersensitivity reactions to an ICM challenge showed negative skin test results. The sensitivity and positive predictive value of skin tests for hypersensitivity reaction to ICM were both 0%. More studies should be conducted to confirm the uselessness of prescreening skin tests. In conclusion, a prescreening intradermal skin test prior to a CT scan has no significant clinical value as a tool for predicting hypersensitivity reactions to ICM. Therefore, prescreening skin tests should not be routinely performed.

Evaluation of Drug-Induced Liver Injury Developed During Hospitalization Using Electronic Health Record (EHR)-Based Algorithm

PURPOSE: The incidence of drug-induced liver injury (DILI) has been increasing; however, few algorithms are available to identify DILI in electronic health records (EHRs). We aimed to identify and evaluate DILI with an appropriate screening algorithm.METHODS: We collected data from 3 university hospitals between June 2015 and May 2016 using our newly developed algorithm for identifying DILI. Among patients with alanine transferase (ALT) ≤ 120 IU/L and total bilirubin (TB) ≤ 2.4 mg/dL in blood test results within 48 hours of admission, those who either had 1) ALT > 120 IU/L and TB > 2.4 mg/dL or 2) ALT > 200 IU/L at least once during hospitalization were identified. After excluding patients with liver disease-related diagnosis at discharge, medical records were retrospectively reviewed to evaluate epidemiological characteristics of DILI.RESULTS: The total number of inpatients was 256,598, of whom 1,100 (0.43%) were selected by the algorithm as suspected DILI. Subsequently, 365 cases (0.14% of total inpatients, 95% confidence interval, 0.13–0.16) were identified as DILI, yielding a positive predictive value of 33.1%. Antibiotics (n = 214, 47.2%) were the major class of causative drug followed by chemotherapeutic agents (n = 87, 19.2%). The most common causative drug was piperacillin-tazobactam (n = 38, 8.4%); the incidence of DILI by individual agent was highest for methotrexate (19.4 cases/1,000 patients administered the drug). Common reasons for excluding suspected DILI cases were ischemic hepatitis and postoperative liver dysfunction.CONCLUSIONS: Using our EHR-based algorithm, we identified that approximately 0.14% of patients developed DILI during hospitalization. Further studies are needed to modify criteria for more accurate identification of DILI.

Risk Factors for Acute Exacerbations in Elderly Asthma: What Makes Asthma in Older Adults Distinctive?

PURPOSE: Asthma in the elderly (EA; ≥ 65 years of age) is increasing, adding a heavy socioeconomic burden to the healthcare system. However, little is known about risk factors associated with acute exacerbations in EA patients. The objective of this study was to investigate risk factors for acute exacerbation in EA compared to non-elderly asthma (NEA).METHODS: We combined data from 3 adult asthma cohorts under a unified protocol and database. Asthmatic patients with regular follow-up during a 1-year period were selected from the cohorts to identify the risk factors predicting acute exacerbations in EA compared to NEA.RESULTS: We selected a total of 1,086 patients from the merged cohort. During the observation period, 503 and 583 patients were assigned to the EA and NEA groups, respectively. The exacerbation rate was 31.0% in the EA and 33.2% in the NEA group. Multivariate logistic regression analysis revealed fixed airway obstruction, chronic rhinosinusitis (CRS), and male sex as independent risk factors for exacerbation in the EA group. In the NEA group, exacerbation increased along with an increase in eosinophil count. Bayesian analysis of the interactions among clinical factors revealed that forced expiratory volume in 1 second/forced vital capacity was directly related to exacerbation in the EA group, and eosinophil count was related to exacerbation in the NEA group.CONCLUSIONS: We suggest that fixed airway obstruction and CRS as the important clinical factors predicting acute exacerbations in EA, whereas in NEA, eosinophil count was the strong predictor of exacerbation.

A Prospective Observation of Psychological Distress in Patients With Anaphylaxis

PURPOSE: Anaphylaxis is an immediate allergic reaction characterized by potentially life-threatening, severe, systemic manifestations. While studies have evaluated links between serious illness and posttraumatic stress disorder (PTSD), few have investigated PTSD after anaphylaxis in adults. We sought to investigate the psychosocial burden of recent anaphylaxis in Korean adults.METHODS: A total of 203 (mean age of 44 years, 120 females) patients with anaphylaxis were recruited from 15 university hospitals in Korea. Questionnaires, including the Impact of Event Scale-Revised-Korean version (IES-R-K), the Korean version of the Beck Anxiety Inventory (K-BAI), and the Korean version of the Beck Depression Inventory (K-BDI), were administered. Demographic characteristics, causes and clinical features of anaphylaxis, and serum inflammatory markers, including tryptase, platelet-activating factor, interleukin-6, tumor necrosis factor-α, and C-reactive protein, were evaluated.RESULTS: PTSD (IES-R-K ≥ 25) was noted in 84 (41.4%) patients with anaphylaxis. Of them, 56.0% had severe PTSD (IES-R-K ≥ 40). Additionally, 23.2% and 28.1% of the patients had anxiety (K-BAI ≥ 22) and depression (K-BDI ≥ 17), respectively. IES-R-K was significantly correlated with both K-BAI (r = 0.609, P < 0.0001) and K-BDI (r = 0.550, P < 0.0001). Among the inflammatory mediators, tryptase levels were lower in patients exhibiting PTSD; meanwhile, platelet-activating factor levels were lower in patients exhibiting anxiety and depression while recovering from anaphylaxis. In multivariate analysis, K-BAI and K-BDI were identified as major predictive variables of PTSD in patients with anaphylaxis.CONCLUSIONS: In patients with anaphylaxis, we found a remarkably high prevalence of PTSD and associated psychological distresses, including anxiety and depression. Physicians ought to be aware of the potential for psychological distress in anaphylactic patients and to consider psychological evaluation.

Oxidative Stress Modulates the Expression Pattern of Peroxiredoxin-6 in Peripheral Blood Mononuclear Cells of Asthmatic Patients and Bronchial Epithelial Cells

PURPOSE: Reduction-oxidation reaction homeostasis is vital for regulating inflammatory conditions and its dysregulation may affect the pathogenesis of chronic airway inflammatory diseases such as asthma. Peroxiredoxin-6, an important intracellular anti-oxidant molecule, is reported to be highly expressed in the airways and lungs. The aim of this study was to analyze the expression pattern of peroxiredoxin-6 in the peripheral blood mononuclear cells (PBMCs) of asthmatic patients and in bronchial epithelial cells (BECs).METHODS: The expression levels and modifications of peroxiredoxin-6 were evaluated in PBMCs from 22 asthmatic patients. Phosphorylated and acetylated peroxiredoxin-6 in hydrogen peroxide-treated human BECs was detected using immunoprecipitation analysis. The expression level of peroxiredoxin-6 was also investigated in BECs treated with hydrogen peroxide. Cycloheximide and proteasome inhibitors were used to determine whether peroxiredoxin-6 is degraded by proteasomes.RESULTS: Peroxiredoxin-6 expression was significantly reduced in the PBMCs of asthmatic patients compared to control subjects. Distinct modification patterns for peroxiredoxin-6 were observed in the PBMCs of asthmatic patients using 2-dimensional-electrophoresis. The levels of phosphorylated serine and acetylated lysine in peroxiredoxin-6 were significantly increased in the BECs following hydrogen peroxide treatment. The level of peroxiredoxin-6 expression was reduced in hydrogen peroxide-stimulated BECs, presumably due to proteasomes.CONCLUSIONS: The expression of peroxiredoxin-6, which is down-regulated in the immune cells of asthmatic patients and BECs, can be modified by oxidative stress. This phenomenon may have an effect on asthmatic airway inflammation.

Prescreening skin test effectiveness in predicting hypersensitivity to iodinated contrast media

Hypersensitivity reaction to iodinated contrast media (ICM) is a persistent clinical issue owing to widespread use of computed tomography (CT) examinations. The question of whether routine performance of skin tests can predict hypersensitivity reactions to contrast media remains unresolved. Recently, a prospective study was performed to evaluate the role of an intradermal skin test as a prescreening test for hypersensitivity reactions to ICM. Fifteen (0.5%) of the 2,843 patients had positive skin test results prior to scheduled CT scans. However, none of the patients experienced a hypersensitivity reaction after administration of full-dose ICM. Meanwhile, 19 patients who experienced hypersensitivity reactions to an ICM challenge showed negative skin test results. The sensitivity and positive predictive value of skin tests for hypersensitivity reaction to ICM were both 0%. More studies should be conducted to confirm the uselessness of prescreening skin tests. In conclusion, a prescreening intradermal skin test prior to a CT scan has no significant clinical value as a tool for predicting hypersensitivity reactions to ICM. Therefore, prescreening skin tests should not be routinely performed.

Therapeutic Effects of Mesenchymal Stem Cells on a Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Model

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are the most severe cutaneous drug hypersensitivity reactions, which are unpredictable adverse drug reactions. SJS/TEN is associated with significant mortality and morbidity; however, effective treatment is difficult. Mesenchymal stem cells (MSCs) are well-known for their anti-inflammatory and tissue regeneration properties. The purpose of the present study was to verify whether MSCs could be applied for the treatment of SJS/TEN. We developed an SJS/TEN mouse model using peripheral blood mononuclear cells from a lamotrigine-induced SJS patient. MSCs were injected into the model to verify the treatment effect. In SJS model mice treated with MSCs, ocular damage rarely occurred, and apoptosis rate was significantly lower. We demonstrated a therapeutic effect of MSCs on SJS/TEN, with these cells presenting a potential novel therapy for the management of this disorder.

Prescreening skin test effectiveness in predicting hypersensitivity to iodinated contrast media

Hypersensitivity reaction to iodinated contrast media (ICM) is a persistent clinical issue owing to widespread use of computed tomography (CT) examinations. The question of whether routine performance of skin tests can predict hypersensitivity reactions to contrast media remains unresolved. Recently, a prospective study was performed to evaluate the role of an intradermal skin test as a prescreening test for hypersensitivity reactions to ICM. Fifteen (0.5%) of the 2,843 patients had positive skin test results prior to scheduled CT scans. However, none of the patients experienced a hypersensitivity reaction after administration of full-dose ICM. Meanwhile, 19 patients who experienced hypersensitivity reactions to an ICM challenge showed negative skin test results. The sensitivity and positive predictive value of skin tests for hypersensitivity reaction to ICM were both 0%. More studies should be conducted to confirm the uselessness of prescreening skin tests. In conclusion, a prescreening intradermal skin test prior to a CT scan has no significant clinical value as a tool for predicting hypersensitivity reactions to ICM. Therefore, prescreening skin tests should not be routinely performed.

Characteristics of Adult Severe Refractory Asthma in Korea Analyzed From the Severe Asthma Registry

PURPOSE: Although mild to moderate asthma is much more common, the morbidity and mortality of severe asthma are much higher. This study was performed to identify and analyze the clinical characteristics of severe asthma in Korea. METHODS: We registered patients with severe refractory asthma into the Severe Asthma Registry supported by the Severe Asthma Work Group of the Korean Academy of Asthma, Allergy and Clinical Immunology. Patients were enrolled since 2010 from the 15 university hospitals nationwide in Korea. Severe asthma was defined according to modified European Respiratory Society/American Thoracic Society criteria. Information on demographics, medical history, pulmonary function tests and skin prick tests was collected; the clinical characteristics of severe asthmatics were analyzed from the collected data. RESULTS: A total of 489 patients were enrolled with a mean age of 62.3; 45% are male. Sixty percent of patients received Global Initiative for Asthma step 4 treatment, and 30% received step 5 treatment. The most common comorbidities were allergic rhinitis (58.7%). Aspirin hypersensitivity was observed in 14.0%. Approximately half (53.9%) are non-smokers. Atopy was proven in 38.5% of the patients. Regarding asthma medications, inhaled corticosteroids and long-acting β-agonist combination inhalers were most commonly prescribed (96.5%), followed by leukotriene antagonists (71.0%). A recombinant anti-immunoglobulin E monoclonal antibody (omalizumab) has been used in 1.8% of the patients. The mean forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and FEV1/FVC were 78.7%, 67.5% and 67.9% of predicted values, respectively. The mean Asthma Control Test and quality of life questionnaire scores were 16.5 out of 25 and 59.5 out of 85, respectively. CONCLUSIONS: The baseline characteristics of severe asthma patients in the Korea Severe Asthma Registry were analyzed and reported for the first time. With this cohort, further prospective studies should be performed to search for ways to improve management of severe refractory asthma.

Multifaceted interventions to reduce acute exacerbations in elderly asthmatics

BACKGROUND: Although many risk factors are known to be associated with poor asthma outcomes in the elderly, the literature on the effect of risk factor control on asthma outcomes in the elderly is very sparse. OBJECTIVE: To evaluate the role of multifaceted interventions in reducing acute exacerbations in elderly asthmatics. METHODS: A total of 100 subjects were randomly selected from our prospective cohort of elderly asthmatics aged 65 years or older and were provided multifaceted intervention for 1 year. Our multifaceted interventions included repeated education on asthma and inhaler technique for patients and their caregivers, provision of an action plan to cope with acute exacerbations, short message service to prevent follow-up losses, and oral replacement of magnesium. The primary outcome was an acute asthma exacerbation rate compared to the previous year. RESULTS: Ninety-two subjects completed this study, although only 58 subjects continued to take magnesium. Compared to the previous year, the acute asthma exacerbation rate showed a significant reduction from 67% to 50% (p = 0001) and significant improvement was observed in forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) (p = 0.04, p = 0.036 for each). Interestingly, a subgroup analysis revealed that predicted value of FEV1 increased significantly in subjects who continued to take magnesium from 79.6% to 87.1% (p = 0.008). CONCLUSION: To reduce acute exacerbations in elderly asthmatics, a multifaceted approach in increase medical awareness, proficiency and adherence to inhaler, assistance of caregivers and correction of micronutrients deficiency is likely to be effective. In addition, a continuous oral replacement of magnesium may increase FEV1 in elderly asthmatics.