Background: This study aimed to generate a Z score calculation model for coronary artery diameter of normal children and adolescents to be adopted as the standard calculation method with consensus in clinical practice. Methods: This study was a retrospective, multicenter study that collected data from multiple institutions across South Korea. Data were analyzed to determine the model that best fit the relationship between the diameter of coronary arteries and independent demographic parameters. Linear, power, logarithmic, exponential, and square root polynomial models were tested for best fit. Results: Data of 2,030 subjects were collected from 16 institutions. Separate calculation models for each sex were developed because the impact of demographic variables on the diameter of coronary arteries differs according to sex. The final model was the polynomial formula with an exponential relationship between the diameter of coronary arteries and body surface area using the DuBois formula. Conclusion A new coronary artery diameter Z score model was developed and is anticipated to be applicable in clinical practice. The new model will help establish a consensus-based Z score model.

An allergy skin test is used to diagnose certain allergies by identifying sensitized allergens. In other words, it is a test for patients who are already sensitized to certain allergens. Because of the prevailing perception that beta-lactam allergy can be dangerous and potentially lethal, the intradermal test has long been routinely performed before use to screen beta-lactam allergy in Korea. The prevalence of penicillin allergy is estimated to be 1% to 2%. However, only 14% of the subjects with perceived penicillin allergy is considered to have true penicillin allergy. Moreover, it is difficult to justify performing a skin test on subjects who are very unlikely to be sensitized to beta-lactam, such as those who never used beta-lactam or never experienced allergy after previous use of beta-lactam.Therefore, allergists recommend beta-lactam skin testing in those who have allergy after the use of beta-lactam. Nevertheless, many hospitals in Korea are conducting routine skin tests on patients regardless of a history of beta-lactam allergy, which are not clinically validated but consume considerable human and material resources. False-positive results can consequently result in inappropriate labeling of beta-lactam allergy, leading to the unnecessary restriction of medication prescriptions and the increase in medical expenses. Herein, the drug allergy working group affiliated with the Korean Academy of Asthma, Allergy, and Clinical Immunology announces an expert opinion on the preuse beta-lactam skin test for subjects without a history of beta-lactam allergy based on the objective evidence from the literature and clinical relevance.

Background/Aims: Standard triple therapy, including a proton pump inhibitor, clarithromycin, and amoxicillin, has been recommended as the first-line for Helicobacter pylori infection. However, the eradication rate of standard triple therapy has declined over the past years because of the increasing resistance to clarithromycin in Korea. We analyzed the eradication rates and the 10-year change in the eradication rates in Korea. Methods: PubMed, EMBASE, the Cochrane Library, and KoreaMed were searched for studies published between January 2007 and June 2018. The pooled eradication rates and their 95% CIs were estimated using a random-effect logistic regression model. Results: Twenty-six randomized controlled studies on standard triple therapy conducted in Korea were selected. The intention-to-treat (ITT) and per protocol analyses showed pooled eradication rates of standard triple therapy of 71.6% (95% CI, 69.9~73.3%) and 79.6% (95% CI, 76.6~82.2%), respectively. The eradication rate decreased with time. The ITT analysis showed that the 14-day therapy (78.1% [95% CI, 75.2~80.7%]) had significantly higher eradication rates than the 7-day therapy (70.0% [95% CI, 68.5~71.4%]) (P<0.01). Conclusions These results suggest that the eradication rate of standard triple therapy, as the first-line therapy, has shown an unacceptable decrease. The eradication rate increased when the duration of therapy was increased to 14 days, but it was not satisfactory. Therefore, other treatment regimens or therapies based on susceptibility tests should be considered for the first-line therapy.

Background/Aims: The eradication rate of the first-line standard triple therapy (STT) for Helicobacter pylori (H. pylori) infection has decreased since 2000; therefore, other first-line therapies are required. This study was aimed at investigating the efficacy of bismuth-containing quadruple therapy (PBMT) for first-line H. pylori eradication compared to STT, sequential therapy (SQT), and concomitant therapy (CT). Materials and Methods: The Ovid-MEDLINE, Koreamed, EMBASE, KMBASE, and Cochrane Library databases were searched from January 2008 to July 2018. All identified randomized controlled trials (RCTs) comparing PBMT and non-PBMT for first-line H. pylori eradication therapy were included in the final analysis. Results: A total of 3,653 patients from seven RCTs were enrolled. The pooled eradication rates of PBMT by intention-to-treat (ITT) and per-protocol (PP) analyses were 82.1% (95% CI, 68.2~90.8%) and 88.8% (95% CI, 77.1~94.9%), respectively. However, no statistically significant difference was observed in eradication rates of the 10- or 14-day PBMT as compared to 14-day STT, 10-day SQT, and 10-day CT in ITT and PP analyses. PBMT was significantly higher in adverse events than in the other eradication regimens (RR, 1.64; 95% CI, 1.11~2.44). Considerable heterogeneity in adverse events was observed among studies (χ2=88.7; P<0.001, I2=93%). Conclusions PBMT can be the first-line treatment for H. pylori eradication in Korea when other first-line options, including STT, SQT, or CT, are unavailable due to their high adverse event rates.

Background/Aims: As antibiotic resistance increases and new first-line therapies emerge, salvage therapies for Helicobacter pylori (H. pylori) eradication failures are becoming more common and complicated. This study aimed to systematically review overall salvage regimens after previous failure of H. pylori eradication. Materials and Methods: A systematic review of randomized clinical trials evaluating salvage therapies after previous H. pylori eradication failure was performed. A meta-analysis was conducted when an adequate number of studies suitable for grouping was found. Results: Overall, 36 studies with 77 treatment arms were identified, and they were highly heterogeneous regarding previously failed regimens and salvage regimens under comparison. Bismuth quadruple therapy after failure of standard triple therapy showed a pooled intention-to-treat (ITT) eradication rate of 75.5% (95% CI, 71.6~79.1%), and the rates were significantly higher with 14-day therapy than 7-day therapy by 9% (95% CI, 2~15%). Levofloxacin triple therapy after failure of standard triple therapy demonstrated a pooled ITT eradication rate of 73.3% (95% CI, 68.4~77.3%). In direct comparison, the two regimens were not significantly different in eradication rates. No study evaluated salvage regimens after the failure of bismuth or non-bismuth quadruple therapy. Conclusions The current studies regarding salvage regimens are highly heterogeneous. Bismuth quadruple therapy and levofloxacin triple therapy may be a reliable option after failure of standard triple therapy, but the regional profile of antibiotic resistance should be considered. Further studies are needed for salvage regimens after failure of non-bismuth or bismuth quadruple therapy.

Helicobacter pylori infection is one of the most common infectious diseases worldwide. H. pylori is responsible for substantial gastrointestinal morbidity with a high disease burden. Since the revision of the H. pylori Clinical Practice Guidelines in 2013 in Korea, the eradication rate of H. pylori has gradually decreased with the use of a clarithromycin based triple therapy. According to a nationwide randomized controlled study by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was mostly due to increased antimicrobial resistance to clarithromycin. The clinical practice guidelines for treatment of H. pylori were updated based on evidence-based medicine from a meta-analysis conducted on a target group receiving the latest level of eradication therapy. The draft recommendations developed based on the meta-analysis were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines were designed to provide clinical evidence for the treatment of H. pylori to patients, nurses, medical school students, policymakers, and clinicians. These may differ from current medical insurance standards, and will be revised if more evidence emerges in the future.

Background: Given the severe shortage of donor liver grafts, coupled with growing proportion of cardiovascular death after liver transplantation (LT), precise cardiovascular risk assessment is pivotal for selecting recipients who gain the greatest survival benefit from LT surgery. We aimed to determine the prognostic value of pre-LT combined measurement of B-type natriuretic peptide (BNP) and high-sensitivity troponin I (hsTnI) in predicting early post-LT mortality. Methods: We retrospectively evaluated 2,490 consecutive adult LT patients between 2010 and 2018. Cut-off values of BNP and hsTnI for predicting post-LT 90-day mortality were calculated. According to the derived cut-off values of two cardiac biomarkers, alone and in combination, adjusted hazard ratios (aHR) of post-LT 90-day mortality were determined using multivariate Cox regression analysis. Results: Mortality rate after 90 days was 2.9% (72/2,490). Rounded cut-off values for post-LT 90-day mortality were 400 pg/ml for BNP (aHR 2.02 [1.15, 3.52], P = 0.014) and 60 ng/L for hsTnI (aHR 2.65 [1.48, 4.74], P = 0.001), respectively. Among 273 patients with BNP ≥ 400 pg/ml, 50.9% of patients were further stratified into having hsTnI ≥ 60 ng/L. Combined use of pre-LT cardiac biomarkers predicted post-LT 90-day mortality rate; both non-elevated: 1.0% (21/2,084), either one is elevated: 9.0% (24/267), and both elevated: 19.4% (27/139, log-rank P < 0.001; aHR vs non-elevated 4.23 [1.98, 9.03], P < 0.001). Conclusions Concomitant elevation of both cardiac biomarkers posed significantly higher risk of 90-day mortality after LT. Pre-LT assessment cardiac strain and myocardial injury, represented by BNP and hsTnI values, would contribute to prioritization of LT candidates and help administer target therapies that could modify early mortality.

Helicobacter pylori (H. pylori) infection is one of the most common infectious diseases worldwide. Although its incidence is gradually decreasing, about half of the world's population still get infected. H. pylori infection is responsible for substantial gastrointestinal morbidity worldwide. It is the most common cause of gastric and duodenal ulcers as well as gastric cancer. Since the revision of the H. pylori Clinical Practice Guidelines in 2013, the eradication rate of H. pylori has gradually decreased with the use of classical triple therapy, wherein amoxicillin, clarithromycin, and proton pump inhibitors are administered, for 7 days. According to a nationwide randomized controlled study conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research released in 2018, the intention-to-treat eradication rate was only 63.9%, which was due to increased antimicrobial resistance induced by the use of antibiotics, especially clarithromycin. The update of clinical practice guideline for treatment of H. pylori was developed based on evidence-based medicine by conducting a meta-analysis. The draft recommendations were finalized after expert consensus on three recommendations regarding the indication for treatment and eight recommendations on the treatment itself. These guidelines are designed to provide patients, nurses, medical school students, policymakers, and clinicians with clinical evidence to guide primary care and treatment of H. pylori infection. These may differ from current medical insurance standards and will be revised further, if necessary, based on research-based evidence.

Background: Given the severe shortage of donor liver grafts, coupled with growing proportion of cardiovascular death after liver transplantation (LT), precise cardiovascular risk assessment is pivotal for selecting recipients who gain the greatest survival benefit from LT surgery. We aimed to determine the prognostic value of pre-LT combined measurement of B-type natriuretic peptide (BNP) and high-sensitivity troponin I (hsTnI) in predicting early post-LT mortality. Methods: We retrospectively evaluated 2,490 consecutive adult LT patients between 2010 and 2018. Cut-off values of BNP and hsTnI for predicting post-LT 90-day mortality were calculated. According to the derived cut-off values of two cardiac biomarkers, alone and in combination, adjusted hazard ratios (aHR) of post-LT 90-day mortality were determined using multivariate Cox regression analysis. Results: Mortality rate after 90 days was 2.9% (72/2,490). Rounded cut-off values for post-LT 90-day mortality were 400 pg/ml for BNP (aHR 2.02 [1.15, 3.52], P = 0.014) and 60 ng/L for hsTnI (aHR 2.65 [1.48, 4.74], P = 0.001), respectively. Among 273 patients with BNP ≥ 400 pg/ml, 50.9% of patients were further stratified into having hsTnI ≥ 60 ng/L. Combined use of pre-LT cardiac biomarkers predicted post-LT 90-day mortality rate; both non-elevated: 1.0% (21/2,084), either one is elevated: 9.0% (24/267), and both elevated: 19.4% (27/139, log-rank P < 0.001; aHR vs non-elevated 4.23 [1.98, 9.03], P < 0.001). Conclusions Concomitant elevation of both cardiac biomarkers posed significantly higher risk of 90-day mortality after LT. Pre-LT assessment cardiac strain and myocardial injury, represented by BNP and hsTnI values, would contribute to prioritization of LT candidates and help administer target therapies that could modify early mortality.

Background/Aims: Standard triple therapy, including a proton pump inhibitor, clarithromycin, and amoxicillin, has been recommended as the first-line for Helicobacter pylori infection. However, the eradication rate of standard triple therapy has declined over the past years because of the increasing resistance to clarithromycin in Korea. We analyzed the eradication rates and the 10-year change in the eradication rates in Korea. Methods: PubMed, EMBASE, the Cochrane Library, and KoreaMed were searched for studies published between January 2007 and June 2018. The pooled eradication rates and their 95% CIs were estimated using a random-effect logistic regression model. Results: Twenty-six randomized controlled studies on standard triple therapy conducted in Korea were selected. The intention-to-treat (ITT) and per protocol analyses showed pooled eradication rates of standard triple therapy of 71.6% (95% CI, 69.9~73.3%) and 79.6% (95% CI, 76.6~82.2%), respectively. The eradication rate decreased with time. The ITT analysis showed that the 14-day therapy (78.1% [95% CI, 75.2~80.7%]) had significantly higher eradication rates than the 7-day therapy (70.0% [95% CI, 68.5~71.4%]) (P<0.01). Conclusions These results suggest that the eradication rate of standard triple therapy, as the first-line therapy, has shown an unacceptable decrease. The eradication rate increased when the duration of therapy was increased to 14 days, but it was not satisfactory. Therefore, other treatment regimens or therapies based on susceptibility tests should be considered for the first-line therapy.