Incidence and Risk Factors of Immediate Hypersensitivity Reactions Associated With Low-Osmolar Iodinated Contrast Media: A Longitudinal Study Based on a Real-Time Monitoring System

OBJECTIVES

We investigated the incidence of immediate hypersensitivity reaction (HSR) caused by different types of low-osmolar contrast media (LOCM) and cumulative exposure to LOCM.

METHODS

This cohort study included all consecutive patients who underwent LOCM-enhanced computed tomography from 2012 through 2014. We assessed 5 LOCM (iobitridol, iohexol, iomeprol, iopamidol, and iopromide). All patients were monitored for adverse events, and new symptoms and signs were recorded in real time using the Contrast Safety Monitoring and Management System (CoSM2oS).

RESULTS

The overall incidence of immediate HSR to LOCM was 0.97% (2004 events resulting from 205 726 exposures). Incidence differed significantly depending on whether the patient had a previous history of HSR to LOCM (0.80% in patients with no history and 16.99% in patients with a positive history of HSR to LOCM, P=.001). The incidence of HSR to individual LOCM ranged from 0.72% (iohexol) to 1.34% (iomeprol), although there were no significant differences across the 5 LOCM. A longitudinal analysis demonstrated that the incidence of HSR increased gradually with more frequent previous exposure to LOCM (HR=2.006 [95%CI, 1.517-2.653], P<.001). However, this cumulative increase in risk was observed in patients who had experienced HSR to LOCM, but not in those who had not.

CONCLUSION

The incidence of HSR did not differ significantly across the 5 LOCM assessed in the study. Repeated exposure to LOCM did not increase the risk of HSR among patients who had never experienced HSR to LOCM.

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.

Inhaled Corticosteroids and Placebo Treatment Effects in Adult Patients With Cough: A Systematic Review and Meta-analysis

PURPOSE

Inhaled corticosteroids (ICSs) are often considered an empirical therapy in the management of patients with cough. However, ICS responsiveness is difficult to interpret in daily clinical practice, as the improvements may include placebo effects or self-remission. We aimed to evaluate ICS and placebo treatment effects in adult patients with cough.

METHODS

Electronic databases were searched for studies published until June 2018, without language restriction. Randomized controlled trials reporting the effects of ICSs compared with placebo in adult patients with cough were included. Random effects meta-analyses were conducted to estimate the treatment effects. Therapeutic gain was calculated by subtracting the percentage change from baseline in the cough score in the ICS treatment group from that in the placebo treatment group.

RESULTS

A total of 9 studies were identified and 8 studies measuring cough severity outcomes were included for meta-analyses. Therapeutic gain from ICSs ranged from -5.0% to +94.6% across the studies included; however, it did not exceed +22%, except for an outlier reporting very high therapeutic gains (+45.6% to +94.6%, depending on outcomes). Overall ICS treatment effects in cough severity outcomes were small-to-moderate (standardized mean difference [SMD], -0.38; 95% confidence interval [CI], -0.54, -0.23), which were comparable between subacute and chronic coughs. However, pooled placebo treatment effects were very large in subacute cough (SMD, -2.58; 95% CI, -3.03, -2.1), and modest but significant in chronic cough (SMD, -0.46; 95% CI, -0.72, -0.21).

CONCLUSIONS

Overall therapeutic gain from ICSs is small-to-moderate. However, placebo treatment effects of ICS are large in subacute cough, and modest but still significant in chronic cough. These findings indicate the need for careful interpretation of ICS responsiveness in the management of cough patients in the clinic, and also for rigorous patient selection to identify ICS-responders.

Cough-Related Laryngeal Sensations and Triggers in Adults With Chronic Cough: Symptom Profile and Impact

Purpose

Recent evidence suggests that cough hypersensitivity may be a common feature of chronic cough in adults. However, the clinical relevance remains unclear. This study evaluated the cough-related symptom profile and the clinical relevance and impact of cough hypersensitivity in adults with chronic cough.

Methods

This cross-sectional multi-center study compared cough-related laryngeal sensations and cough triggers in patients with unexplained chronic cough following investigations and in unselected patients newly referred for chronic cough. A structured questionnaire was used to assess abnormal laryngeal sensations and cough triggers. Patients with unexplained cough were also evaluated using the Leicester Cough Questionnaire (LCQ) and a cough visual analogue scale (VAS), and these scores were assessed for correlations with the number of triggers and laryngeal sensations.

Results

This study recruited 478 patients, including 62 with unexplained chronic cough and 416 with chronic cough. Most participants reported abnormal laryngeal sensations and cough triggers. Laryngeal sensations (4.4 ± 1.5 vs. 3.9 ± 1.9; P = 0.049) and cough triggers (6.9 ± 2.6 vs. 5.0 ± 2.8; P < 0.001) were more frequent in patients with unexplained chronic cough than in those with chronic cough. The number of triggers and laryngeal sensations score significantly correlated with LCQ (r = −0.51, P < 0.001) and cough VAS score (r = 0.53, P < 0.001) in patients with unexplained chronic cough.

Conclusions

Cough hypersensitivity may be a common feature in adult patients with chronic cough, especially those with unexplained chronic cough. Cough-related health status and cough severity were inversely associated with the number of triggers and laryngeal sensations, suggesting potential relevance of assessing cough hypersensitivity in chronic cough patients.

Different Biological Pathways Are Up-regulated in the Elderly With Asthma: Sputum Transcriptomic Analysis

BACKGROUND

Elderly asthma (EA) is increasing, but the pathogenesis is unclear. This study aimed to identify EA-related biological pathways by analyzing genome-wide gene expression profiles in sputum cells.

METHODS

A total of 3,156 gene probes with significantly differential expressions between EA and healthy elderly controls were used for a hierarchical clustering of genes to identify gene clusters. Gene set enrichment analysis provided biological information, with replication from Gene Expression Omnibus expression profiles.

RESULTS

Fifty-five EA patients and 10 elderly control subjects were enrolled. Two distinct gene clusters were found. Cluster 1 (n = 35) showed a lower eosinophil proportion in sputum and less severe airway obstruction compared to cluster 2 (n = 20). The replication data set also identified 2 gene clusters (clusters 1' and 2'). Among 5 gene sets significantly enriched in cluster 1 and 3 gene sets significantly enriched in cluster 2, we confirmed that 2 were significantly enriched in the replication data set (OXIDATIVE_PHOSPHORYLATION gene set in cluster 1 and EPITHELIAL MESENCHYMAL TRANSITION gene set in cluster 2').

CONCLUSIONS

The findings of 2 distinct gene clusters in EA and different biological pathways in each gene cluster suggest 2 different pathogenesis mechanisms underlying EA.

Osseous versus Nonosseous Spinal Epidural Arteriovenous Fistulas: Experiences of 13 Patients

BACKGROUND AND PURPOSE

Spinal epidural arteriovenous fistulas are rare vascular malformations. We present 13 patients with spinal epidural arteriovenous fistulas, noting the various presenting symptom patterns, imaging findings related to bone involvement, and outcomes.

MATERIALS AND METHODS

Among 111 patients with spinal vascular malformations in the institutional data base from 1993 to 2017, thirteen patients (11.7%) had spinal epidural arteriovenous fistulas. We evaluated presenting symptoms and imaging findings, including bone involvement and mode of treatment. To assess the treatment outcome, we compared initial and follow-up clinical status using the modified Aminoff and Logue Scale of Disability and the modified Rankin Scale.

RESULTS

The presenting symptoms were lower back pain (n = 2), radiculopathy (n = 5), and myelopathy (n = 7). There is overlap of symptoms in 1 patient (No. 11). Distribution of spinal epidural arteriovenous fistulas was cervical (n = 3), thoracic (n = 2), lumbar (n = 6), and sacral (n = 2). Intradural venous reflux was identified in 7 patients with congestive venous myelopathy. The fistulas were successfully treated in all patients who underwent treatment (endovascular embolization, n = 10; operation, n = 1) except 2 patients who refused treatment due to tolerable symptoms. Transarterial glue (n = 7) was used in nonosseous types; and transvenous coils (n = 3), in osseous type. After 19 months of median follow-up, the patients showed symptom improvement after treatment.

CONCLUSIONS

Although presenting symptoms were diverse, myelopathy caused by intradural venous reflux was the main target of treatment. Endovascular treatment was considered via an arterial approach in nonosseous types and via a venous approach in osseous types.

A New Standard DNA Damage (SDD) Data Format

Our understanding of radiation-induced cellular damage has greatly improved over the past few decades. Despite this progress, there are still many obstacles to fully understand how radiation interacts with biologically relevant cellular components, such as DNA, to cause observable end points such as cell killing. Damage in DNA is identified as a major route of cell killing. One hurdle when modeling biological effects is the difficulty in directly comparing results generated by members of different research groups. Multiple Monte Carlo codes have been developed to simulate damage induction at the DNA scale, while at the same time various groups have developed models that describe DNA repair processes with varying levels of detail. These repair models are intrinsically linked to the damage model employed in their development, making it difficult to disentangle systematic effects in either part of the modeling chain. These modeling chains typically consist of track-structure Monte Carlo simulations of the physical interactions creating direct damages to DNA, followed by simulations of the production and initial reactions of chemical species causing so-called "indirect" damages. After the induction of DNA damage, DNA repair models combine the simulated damage patterns with biological models to determine the biological consequences of the damage. To date, the effect of the environment, such as molecular oxygen (normoxic vs. hypoxic), has been poorly considered. We propose a new standard DNA damage (SDD) data format to unify the interface between the simulation of damage induction in DNA and the biological modeling of DNA repair processes, and introduce the effect of the environment (molecular oxygen or other compounds) as a flexible parameter. Such a standard greatly facilitates inter-model comparisons, providing an ideal environment to tease out model assumptions and identify persistent, underlying mechanisms. Through inter-model comparisons, this unified standard has the potential to greatly advance our understanding of the underlying mechanisms of radiation-induced DNA damage and the resulting observable biological effects when radiation parameters and/or environmental conditions change.

Early development of de novo hepatocellular carcinoma after direct-acting agent therapy: Comparison with pegylated interferon-based therapy in chronic hepatitis C patients

Patients with chronic hepatitis C who achieve a sustained viral response after pegylated interferon therapy have a reduced risk of hepatocellular carcinoma, but the risk after treatment with direct-acting antivirals is unclear. We compared the rates of early development of hepatocellular carcinoma after direct-acting antivirals and after pegylated interferon therapy. We retrospectively analysed 785 patients with chronic hepatitis C who had no history of hepatocellular carcinoma (211 treated with pegylated interferon, 574 with direct-acting antivirals) and were followed up for at least 24 weeks after antiviral treatment. De novo hepatocellular carcinoma developed in 6 of 574 patients receiving direct-acting antivirals and in 1 of 211 patients receiving pegylated interferon. The cumulative incidence of early hepatocellular carcinoma development did not differ between the treatment groups either for the whole cohort (1.05% vs 0.47%, P = .298) or for those patients with Child-Pugh Class A cirrhosis (3.73% vs 2.94%, P = .827). Multivariate analysis indicated that alpha-fetoprotein level >9.5 ng/mL at the time of end-of-treatment response was the only independent risk factor for early development of hepatocellular carcinoma in all patients (P < .0001, hazard ratio 176.174, 95% confidence interval 10.768-2882.473) and in patients treated with direct-acting agents (P < .0001, hazard ratio 128.402, 95% confidence interval 8.417-1958.680). In conclusion, the rate of early development of hepatocellular carcinoma did not differ between patients treated with pegylated interferon and those treated with direct-acting antivirals and was associated with the serum alpha-fetoprotein level at the time of end-of-treatment response.

Severe Asthma Phenotypes Classified by Site of Airway Involvement and Remodeling via Chest CT Scan

OBJECTIVES

This study aimed to establish a system that can classify severe asthma on the basis of airway remodeling patterns visualizedusing computed tomography (CT) images and to evaluate the clinical characteristics of individual image-based subtypes.

METHODS

Chest CT images from severe asthma patients were retrospectively evaluated to classify phenotypes by site of airway involvement and remodeling. The association between radiologic subtypes and clinical characteristics was assessed.

RESULTS

Of 91 patients with severe asthma, 74 (81.3%) exhibited abnormal radiologic findings, including bronchial wall thickening (BT), mucus plugging (MP), and bronchiectasis (BE). The severity of BT and the extent of MP were independently associated with peripheral blood eosinophil count (P=.012, r2=0.112) and sputum eosinophil count (P=.022, r2=0.090), respectively. The large-to-medium airway remodeling type, which showed diffuse BT combined with MP and BE, accounted for 44% of patients and revealed higher peripheral blood eosinophil counts than other types. In the small airway remodeling type, which accounted for 6.6% of patients, we observed a higher rate of fixed airflow obstruction, along with a predominance of males and smokers and more frequent use of controller medication than other phenotypes. In 26% of patients with severe asthma, no prominent airway remodeling was observed (near-normal type); the near-normal type required oral corticosteroids less frequently than the large-to-medium airway and small airway remodeling types.

CONCLUSIONS

Depending on the site of airway involvement and remodeling pattern, 3 different structural types can be distinguished in chest CT findings from patients with severe asthma. Remodeling in large-to-medium sized airways revealed an association with systemic eosinophilic inflammation in patients with severe asthma.

Genetic parameters of carcass and meat quality traits in different muscles (longissimus dorsi and semimembranosus) of Hanwoo (Korean cattle)

We estimated heritability () and genetic and phenotypic correlations for carcass and meat quality traits of longissimus dorsi (LD) and semimembranosus (SM) muscles in 30-mo-old Hanwoo steers. Variance and covariance components were estimated using REML procedures under univariate and bivariate models. The mean carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), and marbling score (MS) were 428.20 ± 46.30 kg, 87.38 ± 8.54 cm2, 13.00 ± 5.14 mm, and 5.21 ± 1.56, respectively. The mean CIE reflectance of meat lightness (L*), redness (a*), and yellowness (b*) were 40.01 ± 2.73, 22.37 ± 2.18, and 10.35 ± 1.46, respectively, in LD muscles and 36.33 ± 2.44, 22.91 ± 2.43, and 10.25 ± 1.65, respectively, in SM muscles. The mean Warner-Bratzler shear force (WBSF), intramuscular fat content (IMF), water-holding capacity (WHC), and protein and ash content in LD and SM muscles were 3.84 ± 0.96 and 6.52 ± 1.21 kg, 15.91 ± 4.39 and 5.10 ± 1.94%, 62.07 ± 3.38 and 71.61 ± 2.06%, 20.01 ± 1.39 and 21.34 ± 0.89%, and 0.80 ± 0.10 and 0.93 ± 0.07, respectively. The estimates of CWT, EMA, BFT, and MS were 0.51 ± 0.13, 0.45 ± 0.13, 0.29 ± 0.09, and 0.22 ± 0.08, respectively. The estimates were moderate for meat quality traits and were 0.37 ± 0.12, 0.40 ± 0.12, 0.33 ± 0.10, 0.33 ± 0.10, 0.30 ± 0.11, and 0.24 ± 0.09 for L*, WBSF, IMF, WHC, and protein and ash content, respectively, in LD muscle; estimates from SM muscle were comparatively low (0.08 ± 0.06 to 0.25 ± 0.09). Estimates of for a* and b* were also low (0.08 ± 0.06 to 0.13 ± 0.07). Carcass weight had a moderate, positive genetic correlation with EMA (0.60 ± 0.13) and a weak correlation with MS and BFT. The genetic correlations among the 3 colorimeter variants were strong and positive within and between muscles. Intramuscular fat content had moderate to strong and negative genetic correlations with WBSF (-0.49 ± 0.18), WHC (-0.99 ± 0.01), and protein (-0.93 ± 0.04) and ash content (-0.98 ± 0.06) in LD muscle, whereas the associations were less pronounced in SM muscle. In general, CWT and EMA had low genetic and phenotypic correlations with meat quality traits, which suggests that the traits are independent and have distinct genetic contributions in each muscle. Conversely, with few exceptions, meat quality traits had genetic and phenotypic correlations with MS and BFT. In conclusion, the estimated genetic parameters for carcass and meat quality traits could be used for genetic evaluation and breeding programs in Korean Hanwoo cattle populations.

Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey

Purpose

Severe asthma and asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) are difficult to control and are often associated with poor clinical outcomes. However, much is not understood regarding the diagnosis and treatment of severe asthma and ACOS. To evaluate the current perceptions of severe asthma and COPD among asthma and COPD specialists, we designed an e-mail and internet-based questionnaire survey.

Methods

Subjects were selected based on clinical specialty from among the members of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Tuberculosis and Respiratory Diseases. Of 432 subjects who received an e-mail invitation to the survey, 95 subjects, including 58 allergists and 37 pulmonologists, responded and submitted their answers online.

Results

The specialists estimated that the percentage of severe cases among total asthma patients in their practice was 13.9%±11.0%. Asthma aggravation by stepping down treatment was the most common subtype, followed by frequent exacerbation, uncontrolled asthma despite higher treatment steps, and serious exacerbation. ACOS was estimated to account for 20.7% of asthma, 38.0% of severe asthma, and 30.1% of COPD cases. A history of smoking, persistently low forced expiratory volume in 1 second (FEV1), and low FEV1 variation were most frequently classified as the major criteria for the diagnosis of ACOS among asthma patients. Among COPD patients, the highly selected major criteria for ACOS were high FEV1 variation, positive bronchodilator response, a personal history of allergies and positive airway hyperresponsiveness. Allergists and pulmonologists showed different assessments and opinions on asthma phenotyping, percentage, and diagnostic criteria for ACOS.

Conclusions

Specialists had diverse perceptions and clinical practices regarding severe asthma and ACOS patients. This heterogeneity must be considered in future studies and strategy development for severe asthma and ACOS.

Electronic Consultation Support System for Radiocontrast Media Hypersensitivity Changes Clinicians' Behavior

Purpose

Patients with a history of radiocontrast media (RCM) hypersensitivity can be overlooked, resulting in repeated reactions. Therefore, a consultation support system for RCM hypersensitivity has been in operation at Seoul National University Bundang Hospital since December 2011. We analyzed the effect of this system on physicians' practice.

Methods

A retrospective study was conducted on patients with previous RCM reactions (December 1, 2010 to November 30, 2012). The control period was December 2010 to November 2011, and the intervention period was December 2011 to November 2012. The primary outcome was the composite outcome of premedication and consultation. Premedication was defined as preventive medication prescribed by the physician who ordered RCM-enhanced computed tomography (CT) at the same time. The secondary outcome was the recurrence rate after using the consultation support system.

Results

A total of 189 clinicians prescribed 913 CT scans during the control period and 225 clinicians performed 1,153 examinations during the intervention period. The odds ratio (OR) of achieving the composite outcome increased significantly after use of the consultation support system (OR, 1.54; 95% confidence interval [CI], 1.15–2.05). Clinicians in both medical (OR, 1.48; 95% CI, 1.06–2.07) and surgical (OR, 2.07; 95% CI, 1.24–3.46) departments showed significant changes in their behavior, whereas those in the emergency department did not (OR, 1.07; 95% CI, 0.41–2.78). Professors (OR, 1.47; 95% CI, 1.06–2.04) and trainees (OR, 1.97, 95% CI, 1.22–3.18) showed significant changes in their behavior toward patients with previous RCM reactions. The behavior of 86 clinicians who ordered CT scans during both the control and intervention periods was unchanged.

Conclusions

The consultation support system for those with previous RCM hypersensitivity reactions changed physicians' practice patterns and decreased recurrent RCM hypersensitivity reactions as well.

KAAACI Evidence-Based Clinical Practice Guidelines for Chronic Cough in Adults and Children in Korea

Chronic cough is common in the community and causes significant morbidity. Several factors may underlie this problem, but comorbid conditions located at sensory nerve endings that regulate the cough reflex, including rhinitis, rhinosinusitis, asthma, eosinophilic bronchitis, and gastroesophageal reflux disease, are considered important. However, chronic cough is frequently non-specific and accompanied by not easily identifiable causes during the initial evaluation. Therefore, there are unmet needs for developing empirical treatment and practical diagnostic approaches that can be applied in primary clinics. Meanwhile, in referral clinics, a considerable proportion of adult patients with chronic cough are unexplained or refractory to conventional treatment. The present clinical practice guidelines aim to address major clinical questions regarding empirical treatment, practical diagnostic tools for non-specific chronic cough, and available therapeutic options for chronic wet cough in children and unexplained chronic cough in adults in Korea.

PAI-1 gain-of-function genotype, factors increasing PAI-1 levels, and airway obstruction: The GALA II Cohort

BACKGROUND

PAI-1 gain-of-function variants promote airway fibrosis and are associated with asthma and with worse lung function in subjects with asthma.

OBJECTIVE

We sought to determine whether the association of a gain-of-function polymorphism in plasminogen activator inhibitor-1 (PAI-1) with airway obstruction is modified by asthma status, and whether any genotype effect persists after accounting for common exposures that increase PAI-1 level.

METHODS

We studied 2070 Latino children (8-21y) with genotypic and pulmonary function data from the GALA II cohort. We estimated the relationship of the PAI-1 risk allele with FEV1/FVC by multivariate linear regression, stratified by asthma status. We examined the association of the polymorphism with asthma and airway obstruction within asthmatics via multivariate logistic regression. We replicated associations in the SAPPHIRE cohort of African Americans (n=1056). Secondary analysis included the effect of the at-risk polymorphism on postbronchodilator lung function.

RESULTS

There was an interaction between asthma status and the PAI-1 polymorphism on FEV₁ /FVC (P=.03). The gain-of-function variants, genotypes (AA/AG), were associated with lower FEV₁ /FVC in subjects with asthma (β=-1.25, CI: -2.14,-0.35, P=.006), but not in controls. Subjects with asthma and the AA/AG genotypes had a 5% decrease in FEV₁ /FVC (P<.001). In asthmatics, the risk genotype (AA/AG) was associated with a 39% increase in risk of clinically relevant airway obstruction (OR=1.39, CI: 1.01, 1.92, P=.04). These associations persisted after exclusion of factors that increase PAI-1 including tobacco exposure and obesity.

CONCLUSIONS AND CLINICAL RELEVANCE

The decrease in the FEV₁ /FVC ratio associated with the risk genotype was modified by asthma status. The genotype increased the odds of airway obstruction by 75% within asthmatics only. As exposures known to increase PAI-1 levels did not mitigate this association, PAI-1 may contribute to airway obstruction in the context of chronic asthmatic airway inflammation.

Stratified premedication strategy for the prevention of contrast media hypersensitivity in high-risk patients

BACKGROUND

Although the severity of hypersensitivity reactions to iodinated contrast media varies, it is well correlated with the severity of recurrent reactions; however, prophylaxis protocols are not severity-stratified.

OBJECTIVE

To assess the outcomes of tailored prophylaxis according to the severity of hypersensitivity reactions to iodinated contrast media.

METHODS

Our premedication protocols were stratified based on the severity of previous reactions: (1) 4 mg of chlorpheniramine for mild reactions, (2) adding 40 mg of methylprednisolone for moderate reactions, and (3) adding multiple doses of 40 mg of methylprednisolone for severe index reactions. Cases of reexposure in patients with a history of hypersensitivity reactions were routinely monitored and mandatorily recorded.

RESULTS

Among a total of 850 patients who underwent enhanced computed tomography after severity-tailored prophylaxis, breakthrough reactions occurred in 17.1%, but most breakthrough reactions (89.0%) were mild and did not require medical treatment. Additional corticosteroid use did not reduce the breakthrough reaction rate in cases with a mild index reaction (16.8% vs 17.2%, P = .70). However, underpremedication with a single dose of corticosteroid revealed significantly higher rates of breakthrough reaction than did double doses of corticosteroid in cases with a severe index reaction (55.6% vs 17.4%, P = .02). Changing the iodinated contrast media resulted in an additional reduction of the breakthrough reaction rate overall (14.9% vs 32.1%, P = .001).

CONCLUSION

In a total severity-based stratified prophylaxis regimens and changing iodinated contrast media can be considered in patients with a history of previous hypersensitivity reaction to iodinated contrast media to reduce the risk of breakthrough reactions.

A Metagenomic Analysis Provides a Culture-Independent Pathogen Detection for Atopic Dermatitis

Purpose

Atopic dermatitis (AD) is an inflammatory skin disease, significantly affecting the quality of life. Using AD as a model system, we tested a successive identification of AD-associated microbes, followed by a culture-independent serum detection of the identified microbe.

Methods

A total of 43 genomic DNA preparations from washing fluid of the cubital fossa of 6 healthy controls, skin lesions of 27 AD patients, 10 of which later received treatment (post-treatment), were subjected to high-throughput pyrosequencing on a Roche 454 GS-FLX platform.

Results

Microbial diversity was decreased in AD, and was restored following treatment. AD was characterized by the domination of Staphylococcus, Pseudomonas, and Streptococcus, whereas Alcaligenaceae (f), Sediminibacterium, and Lactococcus were characteristic of healthy skin. An enzyme-linked immunosorbent assay (ELISA) showed that serum could be used as a source for the detection of Staphylococcus aureus extracellular vesicles (EVs). S. aureus EV-specific immunoglobulin G (IgG) and immunoglobulin E (IgE) were quantified in the serum.

Conclusions

A metagenomic analysis together with a serum detection of pathogen-specific EVs provides a model for successive identification and diagnosis of pathogens of AD.

Fixed Food Eruption Caused by Actinidia arguta (Hardy Kiwi): A Case Report and Literature Review

Fixed drug eruption (FDE) is a common hypersensitivity reaction characterized by recurrent, well-circumscribed, erythematous patches that arise at the same site as a result of systemic drug exposure. However, fixed food eruption (FFE), a lesion triggered by food ingestion, is a rare allergy that was first defined in 1996. Based on their anti-inflammatory and anti-oxidant properties, the fruit and leaves of Actinidia arguta, the hardy kiwi, are widely consumed across Korea, Japan, and China. This report describes the first case of FFE caused by hardy kiwi leaves, known as Daraesun in Korean, confirmed by oral provocation tests and skin biopsy.

Development and Validation of an Attitudinal-Profiling Tool for Patients With Asthma

Purpose

To develop a profiling tool which accurately assigns a patient to the appropriate attitudinal cluster for the management of asthma.

Methods

Attitudinal data from an online survey of 2,467 patients with asthma from 8 Asian countries/region, aged 18-50 years, having had ≥2 prescriptions in the previous 2 years and access to social media was used in a discriminant function analysis to identify a minimal set of questions for the Profiling Tool. A split-sample procedure based on 100 sets of randomly selected estimation and validation sub-samples from the original sample was used to cross-validate the Tool and assess the robustness of its predictive accuracy.

Results

Our Profiling Tool contained 10 attitudinal questions for the patient and 1 GINA-based level of asthma control question for the physician. It achieved a predictive accuracy of 76.2%. The estimation and validation sub-sample accuracies of 76.7% and 75.3%, respectively, were consistent with the tool's predictive accuracy at 95% confidence level; and their 1.4 percentage-points difference set upper-bound estimate for the degree of over-fitting.

Conclusions

The Profiling Tool is highly predictive (>75%) of the attitudinal clusters that best describe patients with asthma in the Asian population. By identifying the attitudinal profile of the patient, the physician can make the appropriate asthma management decisions in practice. The challenge is to integrate its use into the consultation workflow and apply to areas where Internet resources are not available or patients who are not comfortable with the use of such technology.

Patterns of Inhalant Allergen Sensitization and Geographical Variation in Korean Adults: A Multicenter Retrospective Study

Purpose

Inhalant allergen sensitization is one of the major factors involved in the pathogenesis of allergic respiratory diseases. However, the sensitization is determined by interactions between genetic and environmental factors. Thus, testing panels of inhalant allergens may differ among geographical areas. Here we aimed to determine 10 common inhalant allergens in Korean adult patients with suspected respiratory allergies and to examine the variation between different geographical locations.

Methods

A total of 28,954 patient records were retrieved for retrospective analysis, from 12 referral allergy clinics located in 9 different areas. Inclusion criteria were Korean adults (≥18 years old) who underwent the inhalant allergen skin prick test for suspected history of respiratory allergy. The primary outcome was inhalant allergen skin prick response. Demographic and clinical information were also collected. Positive skin prick responses to allergens were defined as allergen-to-histamine wheal ratio ≥1. Based on skin test results, the most prevalent aeroallergens were determined.

Results

The overall prevalence of allergic sensitization was 45.3%. Dermatophagoides farinae and Dermatophagoides pteronyssinus were the most commonly sensitized allergens. Other common inhalant allergens were cat epithelium (8.1%), birch (7.7%), mugwort (6.9%), alder (6.7%), hazel (6.7%), beech (6.7%), oak (6.6%), and Tyrophagus putres (6.2%), in decreasing order frequency. These 10 inhalant allergens explained 90% of inhalant allergen sensitization in the study participants. However, distinct patterns of the 10 inhalant sensitization were observed in patients living in Chungnam and Jeju. American cockroach, Gernam cockroach, and Trichophyton metagrophytes were unique in Chungnam. Orchard, Japanese cedar, and Velvet were unique in Jeju.

Conclusions

The present analysis suggests a panel of 10 most common inhalant allergens in Korean adult patients with suspected respiratory allergies, which explained 90% of inhalant allergen sensitization. This panel can be utilized as a practical and convenient tool for primary practice and epidemiological surveys of respiratory allergic diseases.

Burden of Respiratory Disease in Korea: An Observational Study on Allergic Rhinitis, Asthma, COPD, and Rhinosinusitis

PURPOSE

The Asia-Pacific Burden of Respiratory Diseases (APBORD) study is a cross-sectional, observational one which has used a standard protocol to examine the disease and economic burden of allergic rhinitis (AR), asthma, chronic obstructive pulmonary disorder (COPD), and rhinosinusitis across the Asia-Pacific region. Here, we report on symptoms, healthcare resource use, work impairment, and associated costs in Korea.

METHODS

Consecutive participants aged ≥18 years with a primary diagnosis of asthma, AR, COPD, or rhinosinusitis were enrolled. Participants and their treating physician completed a survey detailing respiratory symptoms, healthcare resource use, and work productivity and activity impairment. Costs included direct medical cost and indirect cost associated with lost work productivity.

RESULTS

The study enrolled 999 patients. Patients were often diagnosed with multiple respiratory disorders (42.8%), with asthma/AR and AR/rhinosinusitis the most frequently diagnosed combinations. Cough or coughing up phlegm was the primary reason for the medical visit in patients with a primary diagnosis of asthma and COPD, whereas nasal symptoms (watery runny nose, blocked nose, and congestion) were the main reasons in those with AR and rhinosinusitis. The mean annual cost for patients with a respiratory disease was US$8,853 (SD 11,245) per patient. Lost productivity due to presenteeism was the biggest contributor to costs.

CONCLUSIONS

Respiratory disease has a significant impact on disease burden in Korea. Treatment strategies for preventing lost work productivity could greatly reduce the economic burden of respiratory disease.

Age-Related Changes in Immunological Factors and Their Relevance in Allergic Disease Development During Childhood

Purpose

Allergic diseases are triggered by Th2-mediated immune reactions to allergens and orchestrated by various immunological factors, including immune cells and cytokines. Although many reports have suggested that childhood is the critical period in the onset of allergic diseases and aging leads to alter the susceptibility of an individual to allergic diseases, age-related changes in various immunological factors in healthy individuals as well as their difference between healthy and allergic children have not yet been established.

Methods

We investigated the ratio of Th1/Th2 cells and the levels of 22 allergy-related cytokines across all age groups in individuals who were classified as clinically non-atopic and healthy. We also examined their differences between healthy and allergic children to evaluate immunological changes induced by the development of allergic diseases during childhood.

Results

The Th1/Th2 ratio rose gradually during the growth period including childhood, reaching peak values in the twenties-thirties age group. Th1/Th2 ratios were significantly lower in allergic children than in healthy controls, whereas 14 of 22 cytokines were significantly higher in allergic children than in healthy controls. On the other hand, there were no differences in Th1/Th2 ratios and cytokines between healthy and allergic adolescents.

Conclusions

In this study, age-related changes in Th1/Th2 ratios were found in normal controls across all age groups, and decreases in Th1/Th2 ratio were observed with increasing of 14 cytokines in allergic children. The results of this study may be helpful as reference values for both monitoring immunological changes according to aging in healthy individuals and distinguishing between normal and allergic subjects in terms of immune cells and soluble factors.

Development and Validation of a Novel Plasma Protein Signature for Breast Cancer Diagnosis by Using Multiple Reaction Monitoring-based Mass Spectrometry

AIM

We aimed to develop a plasma protein signature for breast cancer diagnosis by using multiple reaction monitoring (MRM)-based mass spectrometry.

MATERIALS AND METHODS

Based on our previous studies, we selected 124 proteins for MRM. Plasma samples from 80 patients with breast cancer and 80 healthy women were used to develop a plasma proteomic signature by an MRM approach. The proteomic signature was then validated in plasma samples from 100 patients with breast cancer and 100 healthy women.

RESULTS

A total of 56 proteins were optimized for MRM. In the verification cohort, 11 proteins exhibited significantly differential expression in plasma from patients with breast cancer. Three proteins (neural cell adhesion molecule L1-like protein, apolipoprotein C-1 and carbonic anhydrase-1) with highest statistical significance which gave consistent results for patients of stage I and II breast cancer were selected and a 3-protein signature was developed using binary logistic regression analysis [area under the curve (AUC)=0.851, sensitivity=80.6%]. The 3-protein signature showed similar performance in an independent validation cohort with an AUC of 0.797 and sensitivity of 77.2% for detection of stage I and II breast cancer.

CONCLUSION

We developed a distinct plasma protein signature for breast cancer diagnosis based on an MRM-based approach, and the clinical value of the 3-protein signature was validated in an independent cohort.