Ji Yeon Lee

Hypervirulent Klebsiella pneumoniae (hvKp) was initially reported predominantly in East Asia and has emerged as a major community-acquired pathogen. In recent years, hvKp has also been recognized a...

Background: South Korea continues to report a considerable burden of drug-resistant tuberculosis (TB). Bedaquiline-containing regimens are recommended for multidrug-resistant pulmonary TB, but evidence regarding the optimal treatment for extrapulmonary manifestations such as spinal TB remains limited. Case presentation: Herein, we report two cases of drug-resistant tuberculous spondylitis that were successfully managed using bedaquiline-containing regimens. Case 1 involved a 67-year-old man who was receiving chemotherapy for lymphoma and had a history of spinal TB treated 20 years earlier. The patient presented with dysphagia and upper limb weakness. Cervical magnetic resonance imaging revealed C4–5 spondylitis with an epidural abscess. He underwent surgical treatment, and Mycobacterium tuberculosis resistant to rifampin was isolated from cultured intraoperatively obtained tissue specimens. The patient received an antibiotic regimen consisting of bedaquiline, levofloxacin, linezolid, cycloserine, and clofazimine. Clinical and radiological improvements were achieved after 12 months of this treatment; bedaquiline was included in the regimen for the first 6 months, while the other agents were continued for the entire course. Case 2 involved a 71-year-old man with T12–L2 spondylitis and a left psoas abscess. Tissue culture confirmed Mycobacterium tuberculosis resistant to isoniazid, rifampin, and ethambutol. The patient was started on the same bedaquiline-containing regimen. Clinical and radiological improvements were observed after 18 months of this therapy, including 6 months of bedaquiline. Conclusions: Our clinical experiences suggest that bedaquiline-containing regimens represent a feasible and effective therapeutic option for drug-resistant tuberculous spondylitis. Larger studies are warranted to establish the optimal management strategies for extrapulmonary drug-resistant TB infections.

Hypervirulent Klebsiella pneumoniae (KP) is defined according to hypermucoviscosity or various virulence factors and is clinically associated with community-acquired liver abscess (CLA). In this study, we investigated the clinical and microbiological characteristics of KP and significant factors associated with hypervirulence. The clinical characteristics, antimicrobial susceptibility, hypermucoviscosity, serotypes, hypervirulence-related genes, and biofilm formation of 414 KP isolates collected from the Keimyung University Dongsan Hospital between December 2013 and November 2015 were analyzed according to CLA. Significant risk factors for hypervirulent KP (HvKP) associated with CLA were investigated using logistic regression analysis. Notably, 155 (37.4%) isolates were hypermucoviscous, and 170 (41.1%) harbored aerobactin. CLA was present in 34 cases (8.2%). Epidemiology and treatment outcomes did not differ significantly between the CLA and non-CLA groups. The CLA group had significantly higher antibiotic susceptibility, K1/K2, rmpA, magA, allS, kfu, iutA, string test-positive result, and biofilm mass. Multivariate logistic regression revealed rmpA (OR, 5.67; 95% CI, 2.09–15.33; p = 0.001), magA (OR, 2.34; 95% CI, 1.01–5.40; p = 0.047), and biofilm mass >0.80 (OR, 2.13; 95% CI, 1.00–4.56; p = 0.050) as significant risk factors for CLA. rmpA was identified as the most significant risk factor for CLA among KP strains, implying that it is an important factor associated with HvKP.

Introduction This study compared the clinical characteristics and antimicrobial susceptibility of uncomplicated acute pyelonephritis (APN) caused by Escherichia coli and Klebsiella pneumoniae. Methods We retrospectively reviewed the medical records of patients with uncomplicated APNs caused by E. coli and K. pneumoniae admitted to Keimyung University Dongsan Hospital between February 2014 and December 2021. Results We enrolled 497 patients (372 with E. coli infection, 125 with K. pneumoniae infection). Male, healthcare-associated infection, solid tumors, liver cirrhosis, chronic renal disease, solid organ transplantation, and antibiotic usage within the last 3 months were more strongly associated with K. pneumoniae uncomplicated APNs than with E. coli. Bacteremia and fever occurred more frequently in E. coli uncomplicated APNs. Antimicrobial resistance rates to piperacillin/tazobactam and carbapenem were higher in K. pneumoniae. Antimicrobial resistance rates to aztreonam and ciprofloxacin were lower in K. pneumoniae. Thirty-day mortality was more observed in K. pneumoniae group in univariate analysis, but this difference was not observed after adjustment. Male sex, ultimately fatal disease in McCabe, and prior antibiotic use within 3 months were more associated with K. pneumoniae. Conclusions Male, underlying diseases, and prior antibiotic use was more associated with K. pneumoniae. Further study will be needed that microbiome of each situation and the related with the distribution of the strains.

Hemorrhagic cholecystitis (HC) is a rare form of cholecystitis that may be caused by the progression of either calculous or acalculous cholecystitis, which has been reported sporadically as case reports. Acalculous cholecystitis is often diagnosed late and can be fulminant. HC without gallstones also can have a poor prognosis and be linked to a high mortality rate. Therefore, early detection, hemodynamic monitoring, and prompt treatment are essential to treat bleeding in cholecystitis. We report a case of hemorrhagic acalculous cholecystitis discovered during the examination and point-of-care ultrasound in a patient with pyogenic spondylodiscitis. The patient was referred with a chief complaint of liver dysfunction without bleeding tendencies or risk factors. Ultrasound revealed focal gallbladder wall irregularity, intraluminal membranes, and non-shadowing non-layering intraluminal echoes. Extravascular contrast leakage was exhibited on the computed tomography scan. The patient underwent emergency percutaneous drainage and subsequent cholecystectomy before developing major complications.

Kwon YS, et al. J Korean Med Sci. 2024 Jan;39:e55. https://doi.org/10.3346/jkms.2024.39.e55

Hypervirulent Klebsiella pneumoniae (K. pneumoniae, hvKP) causes invasive infections, usually community-acquired liver abscess. In this study, we aimed to compare the molecular characteristics and antimicrobial susceptibility of hvKP in community-acquired liver abscess over times, especially before and after COVID-19 outbreak. This study was performed on K. pneumoniae isolates of community-acquired liver abscess collected from Keimyung University Dongsan Hospital from 2014-2015 and 2020-2021. Clinical and microbiologic data were collected from medical records. Capsular serotypes and virulence factors were identified by polymerase chain reaction using specific primers. Molecular characteristics of hypervirulent Klebsiella pneumoniae in community-acquired liver abscess In liver abscess, the virulence factors showed a tendency to increase during the study period such as IutA, but the limitation is that there were small numbers of isolates included in this study. Further studies with larger number of isolates will be required to findout the changing characteristics of hvKP over times. All Authors: No reported disclosures

Introduction Regdanvimab, a neutralising monoclonal antibody (mAb) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), received approval for the treatment of coronavirus disease 2019 (COVID-19) in South Korea in 2021. The Ministry of Food and Drug Safety in South Korea mandate that new medications be re-examined for safety and effectiveness post-approval in at least 3000 individuals. This post-marketing surveillance (PMS) study was used to evaluate the safety and effectiveness of regdanvimab in real-world clinical care. Methods This prospective, multicentre, phase 4 PMS study was conducted between February 2021 and March 2022 in South Korea. Eligible patients were aged ≥ 18 years with confirmed mild COVID-19 at high risk of disease progression or moderate COVID-19. Patients were hospitalised and treated with regdanvimab (40 mg/kg, day 1) and then monitored until discharge, with a follow-up call on day 28. Adverse events (AEs) were documented, and the COVID-19 disease progression rate was used to measure effectiveness. Results Of the 3123 patients with COVID-19 infection identified, 3036 were eligible for inclusion. Approximately 80% and 5% of the eligible patients were diagnosed with COVID-19 during the delta- and omicron-dominant periods, respectively. Median (range) age was 57 (18–95) years, and 50.6% of patients were male. COVID-19 severity was assessed before treatment, and high-risk mild and moderate COVID-19 was diagnosed in 1030 (33.9%) and 2006 (66.1%) patients, respectively. AEs and adverse drug reactions (ADRs) were experienced by 684 (22.5%) and 363 (12.0%) patients, respectively. The most common ADR was increased liver function test (n = 62, 2.0%). Nine (0.3%) patients discontinued regdanvimab due to ADRs. Overall, 378 (12.5%) patients experienced disease progression after regdanvimab infusion, with extended hospitalisation/re-admission (n = 300, 9.9%) as the most common reason. Supplemental oxygen was required by 282 (9.3%) patients. Ten (0.3%) patients required intensive care monitoring and 3 (0.1%) died due to COVID-19. Conclusion This large-scale PMS study demonstrated that regdanvimab was effective against COVID-19 progression and had an acceptable safety profile when used in real-world clinical practice.

Si-Ho Kim, Yu Mi Wi, Chisook Moon, Ji-Man Kang, Minhwa Kim, Jungok Kim, Jong Man Kim, Hyeri Seok, Hye Jin Shi, Su Jin Lee, Ji Yeon Lee, Su Jin Jeong, Pyoeng Gyun Choe, Kyungmin Huh, Sang-Oh Lee, Sang Il Kim; Transplant Infection Research Committee of the Korean Society of Infectious Diseases. Korean J Transplant -0001;0:. https://doi.org/10.4285/kjt.23.0034