Performance of Remsima® Monitor Drug Level versus RIDASCREEN IFX Monitoring in therapeutic drug monitoring of infliximab in patients with inflammatory bowel disease: A study of diagnostic accuracy

Therapeutic drug monitoring (TDM) is effective in optimizing the efficacy of infliximab in patients with inflammatory bowel disease (IBD). An affordable way of monitoring is in high demand. This study evaluated the analytical and clinical performances of the newly available Remsima monitor kits and compared them with the established enzyme-linked immunosorbent assay kits. The trough level of infliximab in patients with IBD treated with an infliximab originator (Remicade) or biosimilar compounds (Remsima and Remaloce) was measured using a Remsima® Monitor Drug Level (Remsima) kit at the Samsung Medical Center, Seoul, Korea. Twenty-six plasma samples were collected immediately before the infusion of infliximab from 18 patients with IBD (Remicade, n = 8; Remsima, n = 6; and Remaloce, n = 4). The intra-assay intraclass correlation coefficient (ICC) of the RIDA and Remsima kits was 0.951 (95% CI = 0.908–0.976) and 0.990 (95% CI = 0.981–0.995). The inter-assay ICC of infliximab trough level between the RIDA and Remsima kits was very high (R = 0.971; 95% CI = 0.935–0.987), and the mean difference between the kits was 1.458 (95% limits of agreement = −3.302 to 6.219). The intra- and inter-assay reliabilities of all types of infliximab did not show significant differences. Qualitative stratification revealed substantial similarities between the kits (weighted kappa = 0.798). This study indicated that the Remsima kit was reproducible and highly correlated with the RIDA kit.     

Association of renal function with muscle strength in Korean adults: A population-based study using the Korea National Health and Nutrition Examination Surveys (KNHANES) from 2014 to 2018

Hand grip strength (HGS), a simple measure of upper limb muscle function, can be used to assess overall muscular strength, and reduced HGS in patients with poor renal functions has been observed. This study examined the associations between renal function and HGS, a surrogate marker of muscular strength, among a stratified sample of Korean adults. This study obtained data from the Korea National Health and Nutrition Examination Survey from 2014 to 2018, a cross-sectional and nationally representative survey conducted by the Korea Centers for Diseases Control and Prevention. In men, low muscle strength (LMS) and normal muscle strength (NMS) were defined as HGS < 28.9 kg and HGS ≥ 28.9 kg, respectively. In women, LMS and NMS were considered as HGS < 16.8 kg and HGS ≥ 16.8 kg, respectively. Of the 25,746 subjects in this study, there were 3603 (14.0%) and 22,143 (86.0%) subjects who displayed LMS and NMS, respectively. Subjects with estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² had a higher risk of developing LMS than those with eGFR ≥ 60 mL/min/1.73 m² after adjusting for age (odds ratio, 1.772; 95% CI, 1.498–2.096); the significant differences remained after adjusting for other factors including age. Similar tendencies were shown in men and women when analyzed according to gender; however, the risk of developing LMS was higher in men than in women. Results showed that decreased renal function was likely to contribute to an increased prevalence of LMS based on HGS. This association may assist in developing better strategies to estimate renal function in clinical or public health practice.     

Reducing Knee Joint Load during a Golf Swing: The Effects of Ball Position Modification at Address

As the modern golf swing has changed, the incidence of knee pain in professional golfers is increasing. For those with previous knee injuries, developing a golf-swing modification that reduces knee loading may be necessary to recover performance after injury. The purpose of this study was to test whether ball position modification reduces knee joint load in a golf swing. Thirteen male professional golfers participated in the study. Golf swings were captured using a three-dimensional motion capture system and two force platforms, with conditions for self-selected ball position and eight additional ball positions. Knee internal rotation and adduction moments were calculated. The length of one golf ball (4.27 cm) backward ball position (closer to the golfer) significantly reduced the peak internal rotation moment of the lead knee (- 13.8%) (p < 0.001) and the length of one golf ball (4.27 cm) away from the target ball position significantly reduced the peak adduction moment of the lead knee (- 11.5%) (p < 0.001) compared with that of the self-selected ball position. Based on these observations, we conclude that the backward ball position modification might be suggested for golfers with anterior cruciate ligament injuries, and the away from the target modification might be suggested for golfers with medial compartment knee osteoarthritis. Key points

• One ball position (4.27 cm) backward with respect to the self-selected ball position (backward-full) reduces the internal rotation moment of the lead knee during golf swing and is a suggested modification for golfers with ACL injuries.
• One ball position (4.27 cm) away from the target with respect to the self-selected ball position (away-full) reduces the adduction moment of the lead knee during the golf swing and is a suggested modification for golfers with medial compartment knee OA;
• The moving the ball position a distance of one ball length away from target also increases an in-out club path and is a suggested modification for golfers particularly with having an out-in club path.

Key words: Sports injury, anterior cruciate ligament, osteoarthritis, knee internal rotation moment, knee adduction moment     

Musculoskeletal Pain and the Prevalence of Rheumatoid Arthritis in Breast Cancer Patients During Cancer Treatment: A Retrospective Study

PurposeBreast cancer patients often develop musculoskeletal pain, resembling that experienced by patients with rheumatoid arthritis (RA), during cancer treatment. This study aimed to investigate the causes of musculoskeletal pain, including RA, among breast cancer patients.MethodsThis retrospective study included breast cancer patients experiencing new-onset arthralgia during cancer treatment along with age- and sex-matched controls without breast cancer, who were evaluated at the Rheumatologic clinic between 2004 and 2017. The causes of musculoskeletal pain were compared between breast cancer patients and controls. The effects of cancer treatment on arthralgia and factors associated with RA were examined.ResultsA total of 146 breast cancer patients and 102 controls were included in the final analysis. The most common cause of arthralgia during breast cancer treatment was osteoarthritis (OA, 61.0%), followed by enthesopathy/tendinopathy (28.1%), which included tendinitis, adhesive capsulitis, and carpal tunnel syndrome. Overall, 50.0% of 72 breast cancer patients receiving aromatase inhibitors (AIs) satisfied the criteria of AI-induced musculoskeletal symptoms (AIMSS). The mean symptom duration (i.e., the time between pain onset and evaluation by a rheumatologist) was shorter in breast cancer patients than in controls (7.0 ± 12.1 vs. 14.8 ± 24.9 months, respectively; p = 0.004). RA was diagnosed in 3 (2.1%) breast cancer patients and 3 (2.9%) controls. All breast cancer patients with RA had an elevated erythrocyte sedimentation rate (ESR, 66.7 ± 25.0 mm/h), whereas those without RA had a normal ESR (20.4 ± 21.5 mm/h). Patients with breast cancer required more analgesics than the controls.ConclusionOA and enthesopathy/tendinopathy are the most common causes of arthralgia in breast cancer patients, which may concurrently manifest as AIMSS. Patients with breast cancer did not have a higher prevalence of RA than those without breast cancer.     

The Korea Cohort Consortium: The Future of Pooling Cohort Studies

ObjectivesWe introduced the cohort studies included in the Korean Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies.MethodsWe mainly focused on the characteristics of individual cohort studies from the KCC. We developed “PROFAN”, a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated.ResultsThe KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917–72 102.ConclusionsWe propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.     

Management of Contacts of the First Imported Monkeypox Case in Korea

On 22 June, a man who returned to South Korea from Germany tested positive for the monkeypox virus using real-time polymerase chain reaction. We identified 49 contacts concerning the first monkeypox case and classified them into two groups based on risk exposure levels. Through active monitoring of eight people in the medium-risk group and passive monitoring of 41 people in the low-risk group, we identified that no secondary transmission occurred over 21 days. The prompt active or passive monitoring of the index case of imported monkeypox could prevent community transmission in Korea.     

Relative Effectiveness of COVID-19 Vaccination in Healthcare Workers: 3-Dose Versus 2-Dose Vaccination

The omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to have high infectivity and is more likely to evade vaccine immunity. However, booster vaccination is expected to strengthen cross-reactive immunity, thereby increasing the vaccine effectiveness (VE). This study aimed to evaluate the relative VE of the 3-dose (booster) vaccination compared with the 2-dose primary series vaccination in healthcare workers during omicron variant-dominant periods. During the omicron-dominant period from February 1, 2022 to February 28, 2022, a 1:1 matched case-control study was conducted. Healthcare workers with positive SARS-CoV-2 test results were classified as positive cases, whereas those with negative results served as controls. Compared with the 2-dose primary series vaccination, booster vaccination with mRNA vaccine showed moderate VE (53.1%). However, in multivariate analysis including the time elapsed after vaccination, the significant VE disappeared, reflecting the impact of recent vaccination rather than the third dose itself.     

Population Prevalence,Cancer Risk,and Mortality Risk of Turner Syndrome in South Korean Women Based on National Health Insurance Service Data

PurposeIn South Korea, investigations into Turner syndrome (TS) prevalence and TS-associated cancer and mortality are lacking. Accurate data were estimated from the National Health Insurance Service (NHIS) and the Rare Diseases Registry (RDR) records.Materials and MethodsData on patients with TS who were registered in the RDR between 2007 and 2017 were collected. To estimate TS-associated cancer and mortality risk, the data were compared with data of 1:3 age-matched controls.ResultsIn 2017, 2054 patients with TS were identified from a total population of 26186952 South Korean women; therefore, the prevalence was 7.84 per 100000 persons. TS prevalence across 10-year interval age groups were 11.82, 23.17, 18.37, 10.49, 4.09, and 0.38 for age under 10 years, teenagers, 20s, 30s, 40s, and older than 50, respectively (per 100000 persons). The cancer risk in patients with TS was higher than that of age-matched controls over 5.3 person-years [hazard ratio (HR)=1.82, 95% confidence interval (CI) 1.01–3.27, p=0.045]. Among different types of cancer, thyroid cancer risk in patients with TS was significantly higher than that of age-matched controls (HR=2.78, 95% CI 1.06–7.26, p=0.037). We also observed that TS-associated all-cause mortality risk was higher than that of age-matched controls (HR=3.36, 95% CI 1.59–7.10, p=0.002).ConclusionNational prevalence of TS was suggested, and an increased risk of TS-associated thyroid cancer and mortality were observed in this study.     

Evaluation of Five User-Friendly Whole Genome Sequencing Software for Mycobacterium tuberculosis in Clinical Application

BackgroundWhole genome sequencing (WGS) is an increasingly useful tool for tuberculosis (TB) diagnosis and disease management. In this study, we evaluated the utility of user-friendly WGS tools in reporting resistance profiles and identifying lineages of clinical TB isolates from South Korea.MethodsForty clinical samples from TB patients showing discrepancies between their rapid molecular and conventional drug susceptibility tests were used in this study. Among these clinical isolates, 37 strains were successfully evaluated via WGS software, using the GenTB, TB Profiler, PhyResSE, CASTB, and Mykrobe.ResultsMore accurate and faster susceptibility results could be obtained with isoniazid than with rifampin. Using the phenotypic test as the gold standard, the isoniazid concordance rate between phenotypic drug susceptibility test (DST) and WGS (GenTB: 45.9%, TB profiler: 40.5%, PhyResSE: 40.5%, CASTB: 48.6%, and Mykrobe: 43.2%) was much higher than between phenotypic DST and rapid molecular genotypic DST (18.9%) among the 37 strains. In contrast, the rifampin concordance rate between phenotypic DST and WGS and that between phenotypic DST and rapid molecular genotypic DST was similar (81.1–89.2%). We also found novel mutations associated with INH in katG and ahpC gene region, not covered by the line probe assay. In addition, lineage analysis identified 81.1% of these samples as L2 East Asian lineage strains, and 18.9% as L4 Euro-American lineage strains.ConclusionWGS may play a pivotal role in TB diagnosis and the detection of drug resistance, genetic diversity, and transmission dynamics in the near future because of its accuracy, speed, and extensibility.