Objectives: The standard first-line treatment for Helicobacter pylori infection typically involves proton pump inhibitors, amoxicillin, and clarithromycin (PAC), yet the eradication success rates are not entirely satisfactory. Recognizing bismuth’s antibacterial properties and its potential to enhance antibiotic efficacy, this study compared the eradication success rates of a 7-day course of PAC with bismuth (PACB) versus PAC alone in patients with clarithromycin-susceptible H. pylori infections. Methods: We conducted a retrospective review at Eunpyeong St. Mary’s Hospital involving 499 patients with confirmed clarithromycin-susceptible H. pylori infection. These patients were treated either with PACB or PAC for 7 days. Clarithromycin resistance-associated point mutations were evaluated using reverse transcriptase polymerase chain reaction. Successful eradication was confirmed by a negative 13C-urea breath test. Results: Of the patients, 261 received PACB therapy, and 238 received PAC therapy. The intention-to-treat analysis showed eradication success rates of 82.8% (216/261) for PACB and 89.1% (212/238) for PAC (p=0.093). The per-protocol analysis revealed eradication rates of 85.3% (215/252) for PACB and 90.5% (210/232) for PAC (p=0.081). The incidence of adverse effects was similar between the two groups, with 41.3% (104/252) in the PACB group and 34.1% (79/232) in the PAC group (p=0.102). Conclusions Adding bismuth to the standard 7-day PAC regimen did not significantly increase eradication rates in patients with clarithromycin-susceptible H. pylori infections compared to PAC alone.

Background: This study aimed to identify the clinical characteristics of multidrug-resistant/ rifampicin-resistant tuberculosis (MDR/RR-TB) in the Republic of Korea. Methods: Data of notified people with tuberculosis between July 2018 and December 2021 were retrieved from the Korea Tuberculosis Cohort database. MDR/RR-TB was further categorized according to isoniazid susceptibility as follows: multidrug-resistant tuberculosis (MDR-TB), rifampicin-monoresistant tuberculosis (RMR-TB), and RR-TB if susceptibility to isoniazid was unknown. Multivariable logistic regression analysis was conducted to identify the factors associated with MDR/RR-TB. Results: Between 2018 and 2021, the proportion of MDR/RR-TB cases among all TB cases and TB cases with known drug susceptibility test results was 2.1% (502/24,447). The proportions of MDR/RR-TB and MDR-TB cases among TB cases with known drug susceptibility test results were 3.3% (502/15,071) and 1.9% (292/15,071), respectively. Among all cases of rifampicin resistance, 31.7% (159/502) were RMR-TB and 10.2% (51/502) were RR-TB. Multivariable logistic regression analyses revealed that younger age, foreigners, and prior tuberculosis history were significantly associated with MDR/ RR-TB. Conclusion Rapid identification of rifampicin resistance targeting the high-risk populations, such as younger generations, foreign-born individuals, and previously treated patients are necessary for patient-centered care.

Purpose: To investigate the clinical characteristics of South Korean patients with pericentral retinitis pigmentosa (RP) and to identify clinical biomarkers associated with rapid visual acuity decline based on baseline factors. Methods: This retrospective study included 59 eyes of 31 patients diagnosed with pericentral RP. Comprehensive ophthalmological examinations and genetic sequencing were conducted to assess the baseline characteristics. For biomarker analysis, eyes were categorized into two groups based on the annual rate of change in visual acuity. The clinical findings of the two groups were evaluated to identify the biomarkers associated with rapid loss of visual acuity. Results: Patients with pericentral RP in this study exhibited a mean best-corrected visual acuity of 0.17 ± 0.23 in logarithm of the minimum angle of resolution. The visual field test showed annular or semicircular scotoma with relatively preserved periphery and 27 eyes (45.8%) exhibited no macular complications in optical coherence tomography. Genetic analysis identified genes associated with previous typical and pericentral RP studies but also highlighted that many genetic causes of pericentral RP remain unidentified. Of the 55 eyes for which the rate of visual acuity change could be estimated, 18 exhibited an annual decline of ≥10%, whereas 37 showed an annual decline of <10%. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram correlated with rapid visual acuity decline in the multivariate analysis. Conclusions South Korean patients with pericentral RP exhibited a milder phenotype compared to typical RP patients reported in previous studies. Genetic analysis revealed heterogeneity, with mutations in some genes commonly associated with milder forms of RP. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram were significant biomarkers for predicting rapid visual acuity decline. Monitoring initial b-wave latency is important for predicting visual decline, particularly in male patients with pericentral RP.

Purpose: To investigate the clinical characteristics of South Korean patients with pericentral retinitis pigmentosa (RP) and to identify clinical biomarkers associated with rapid visual acuity decline based on baseline factors. Methods: This retrospective study included 59 eyes of 31 patients diagnosed with pericentral RP. Comprehensive ophthalmological examinations and genetic sequencing were conducted to assess the baseline characteristics. For biomarker analysis, eyes were categorized into two groups based on the annual rate of change in visual acuity. The clinical findings of the two groups were evaluated to identify the biomarkers associated with rapid loss of visual acuity. Results: Patients with pericentral RP in this study exhibited a mean best-corrected visual acuity of 0.17 ± 0.23 in logarithm of the minimum angle of resolution. The visual field test showed annular or semicircular scotoma with relatively preserved periphery and 27 eyes (45.8%) exhibited no macular complications in optical coherence tomography. Genetic analysis identified genes associated with previous typical and pericentral RP studies but also highlighted that many genetic causes of pericentral RP remain unidentified. Of the 55 eyes for which the rate of visual acuity change could be estimated, 18 exhibited an annual decline of ≥10%, whereas 37 showed an annual decline of <10%. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram correlated with rapid visual acuity decline in the multivariate analysis. Conclusions South Korean patients with pericentral RP exhibited a milder phenotype compared to typical RP patients reported in previous studies. Genetic analysis revealed heterogeneity, with mutations in some genes commonly associated with milder forms of RP. Male sex and prolonged b-wave latency on dark-adapted 0.01 electroretinogram were significant biomarkers for predicting rapid visual acuity decline. Monitoring initial b-wave latency is important for predicting visual decline, particularly in male patients with pericentral RP.

Objectives: The standard first-line treatment for Helicobacter pylori infection typically involves proton pump inhibitors, amoxicillin, and clarithromycin (PAC), yet the eradication success rates are not entirely satisfactory. Recognizing bismuth’s antibacterial properties and its potential to enhance antibiotic efficacy, this study compared the eradication success rates of a 7-day course of PAC with bismuth (PACB) versus PAC alone in patients with clarithromycin-susceptible H. pylori infections. Methods: We conducted a retrospective review at Eunpyeong St. Mary’s Hospital involving 499 patients with confirmed clarithromycin-susceptible H. pylori infection. These patients were treated either with PACB or PAC for 7 days. Clarithromycin resistance-associated point mutations were evaluated using reverse transcriptase polymerase chain reaction. Successful eradication was confirmed by a negative 13C-urea breath test. Results: Of the patients, 261 received PACB therapy, and 238 received PAC therapy. The intention-to-treat analysis showed eradication success rates of 82.8% (216/261) for PACB and 89.1% (212/238) for PAC (p=0.093). The per-protocol analysis revealed eradication rates of 85.3% (215/252) for PACB and 90.5% (210/232) for PAC (p=0.081). The incidence of adverse effects was similar between the two groups, with 41.3% (104/252) in the PACB group and 34.1% (79/232) in the PAC group (p=0.102). Conclusions Adding bismuth to the standard 7-day PAC regimen did not significantly increase eradication rates in patients with clarithromycin-susceptible H. pylori infections compared to PAC alone.

Background: This study aimed to identify the clinical characteristics of multidrug-resistant/ rifampicin-resistant tuberculosis (MDR/RR-TB) in the Republic of Korea. Methods: Data of notified people with tuberculosis between July 2018 and December 2021 were retrieved from the Korea Tuberculosis Cohort database. MDR/RR-TB was further categorized according to isoniazid susceptibility as follows: multidrug-resistant tuberculosis (MDR-TB), rifampicin-monoresistant tuberculosis (RMR-TB), and RR-TB if susceptibility to isoniazid was unknown. Multivariable logistic regression analysis was conducted to identify the factors associated with MDR/RR-TB. Results: Between 2018 and 2021, the proportion of MDR/RR-TB cases among all TB cases and TB cases with known drug susceptibility test results was 2.1% (502/24,447). The proportions of MDR/RR-TB and MDR-TB cases among TB cases with known drug susceptibility test results were 3.3% (502/15,071) and 1.9% (292/15,071), respectively. Among all cases of rifampicin resistance, 31.7% (159/502) were RMR-TB and 10.2% (51/502) were RR-TB. Multivariable logistic regression analyses revealed that younger age, foreigners, and prior tuberculosis history were significantly associated with MDR/ RR-TB. Conclusion Rapid identification of rifampicin resistance targeting the high-risk populations, such as younger generations, foreign-born individuals, and previously treated patients are necessary for patient-centered care.