Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

Background: and Purpose This study evaluated the diagnostic utility of an anti-signal-recognition particle 54 (anti-SRP54) antibody-based enzyme-linked immunosorbent assay (ELISA) as well as the clinical, serological, and pathological characteristics of patients with SRP immune-mediated necrotizing myopathy (IMNM). Methods: We evaluated 87 patients with idiopathic inflammatory myopathy and 107 healthy participants between January 2002 and December 2023. The sensitivity and specificity of the ELISA for anti-SRP54 antibodies were assessed, and the clinical profiles of patients with antiSRP54 antibodies were determined. Results: The ELISA for anti-SRP54 antibodies had a sensitivity and specificity of 88% and 99%, respectively, along with a test–retest reliability of 0.92 (p<0.001). The 32 patients diagnosed with anti-SRP IMNM using a line-blot immunoassay included 28 (88%) who tested positive for anti-SRP54 antibodies using the ELISA, comprising 12 (43%) males and 16 (57%) females whose median ages at symptom onset and diagnosis were 43.0 years and 43.5 years, respectively. Symptoms included proximal muscle weakness in all 28 (100%) patients, neck weakness in 9 (32%), myalgia in 15 (54%), dysphagia in 5 (18%), dyspnea in 4 (14%), dysarthria in 2 (7%), interstitial lung disease in 2 (7%), and myocarditis in 2 (7%). The median serum creatine kinase (CK) level was 7,261 U/L (interquartile range: 5,086–10,007 U/L), and the median anti-SRP54 antibody level was 2.0 U/mL (interquartile range: 1.0–5.6 U/mL). The serum CK level was significantly higher in patients with coexisting anti-Ro-52 antibodies. Conclusions This study has confirmed the reliability of the ELISA for anti-SRP54 antibodies and provided insights into the clinical, serological, and pathological characteristics of South Korean patients with anti-SRP IMNM.

Objective: To determine the preventive effect of changing gadolinium-based contrast agents (GBCAs) to reduce the recurrence of GBCA-associated acute adverse drug reactions (ADRs). Materials and Methods: This retrospective, observational, single-center study—conducted between January 2016 and December 2021—included 238743 consecutive GBCA-enhanced MRI examinations. We focused on a subgroup of patients who experienced acute GBCA-associated ADRs during any of these examinations and subsequently underwent follow-up GBCAenhanced MRI examinations up until July 2023. The follow-up examinations involved either the same (non-change group) or different (change group) GBCAs compared to the ones that initially caused the acute ADR. Baseline participant characteristics, generic profile of the GBCAs, administration of premedication, history of prior ADR to iodinated contrast media, and symptoms of GBCA-associated acute ADRs were retrospectively analyzed. Multivariable logistic regression with generalized estimating equations and propensity score matching were used. Results: A total of 1042 instances of acute ADRs (0.44%; 95% confidence interval [CI]: 0.41%–0.46%) were reported. Threehundred and seventy-three patients underwent GBCA-enhanced MRI examinations after experiencing GBCA-associated acute ADRs within the study period; 31.9% (119/373) reexperienced acute ADRs at any of the follow-up examinations. The ADR recurrence was significantly lower in the GBCA change group than in the non-change group according to multivariable logistic regression (adjusted odds ratio [OR]: 0.35; 95% CI: 0.13–0.90; P = 0.03) and analysis with propensity score matching (14.3% [6/42] vs. 36.9% [31/84], respectively; OR: 0.32, 95% CI: 0.11–0.94; P = 0.04). A history of an ADR to iodinated contrast media (OR: 1.14, 95% CI: 0.68–1.90; P = 0.62) and premedication (adjusted OR: 2.09, 95% CI: 0.93–4.68; P = 0.07) were not significantly associated with GBCA-associated acute ADR recurrence. A separate analysis for recurrent allergic-like hypersensitivity reactions demonstrated similar results (adjusted OR: 0.20, 95% CI: 0.06–0.65; P < 0.01). Conclusion Changing GBCAs may reduce the risk of GBCA-associated acute ADR recurrence.

Purpose: There has been little information about the impact of coronavirus disease 2019 (COVID-19) pandemic on esophagogastroduodenoscopy (EGD) and gastric cancer claims. This study aimed to measure the impact of COVID-19 pandemic on EGD and gastric cancer claims in South Korea. Materials and Methods: This nationwide, population-based study compared the claims data of EGD, gastric cancer, early gastric cancer (EGC), advanced gastric cancer (AGC) and gastric cancer operation in 2020 and 2021 (COVID-19 era) to those in 2019 (before COVID-19 pandemic). Results: The annual claims of EGD, gastric cancer, EGC, and AGC were reduced by 6.3%, 5.0%, 4.7%, and 3.6% in 2020 and by 2.2%, 1.0%, 0.6%, and 1.9% in 2021, respectively, compared to 2019. The amount of annual claims of gastric cancer operation was reduced by 8.8% in 2020, but increased by 0.9% in 2021, compared to those in 2019. The monthly claims of EGD, gastric cancer, EGC, AGC, and gastric cancer operation were mainly reduced in the first epidemic wave of COVID-19, but decreased in the 2nd to 4th epidemic wave. Compared to 2019, the monthly claim of EGD, gastric cancer, EGC, AGC, and gastric cancer operation were reduced by 28.8%, 14.3%, 18.1%, 9.2%, and 5.8% in March 2020 and by 17.2%, 10.8%, 10.3%, 7.2%, and 35.4% in April 2020, respectively. Conclusion Negative impact of the COVID-19 pandemic on EGD, gastric cancer, EGC, AGC, and gastric cancer operation was worst during the first surge of COVID-19, but decreased in the 2nd to 4th epidemic wave of the disease in 2020 and 2021.