ABSTRACT
As nucleocapsid protein of severe acute respiratory syndrome coronavirus 2 is immunogenic but not targeted in vaccines, it could be useful in distinguishing natural infection from vaccination. We aimed to investigate the clinical utility of sero-immunological responses against the nucleocapsid protein. Nucleocapsid antibody immunoassay study with 302 coronavirus disease 2019 (COVID-19) patients showed lower titers in immunocompromised patients (P < 0.001), higher titers in higher severity (P = 0.031), and different seroconversion rates and titers according to variants of concern. Longitudinal evaluation of nucleocapsid antibodies using 513 samples from 291 COVID-19 patients revealed that it could persist up to 556 days from symptom onset. Interferon gamma release assay against the nucleocapsid protein showed poor response, precluding the deduction of a cut-off for the nucleocapsid protein. In conclusion, nucleocapsid antibody provides instructive clues about the immunogenicity of nucleocapsid proteins by different seroconversion rates and titers according to the severity of infection, host immune status, and different variants of concern.
ABSTRACT
Tixagevimab/cilgavimab is a monoclonal antibody used to prevent coronavirus disease 2019 among immunocompromised hosts and maintained neutralizing activity against early omicron variants. Omicron BN.1 became a dominant circulating strain in Korea early 2023, but its susceptibility to tixagevimab/cilgavimab is unclear. We conducted plaque reduction neutralization test (PRNT) against BN.1 in a prospective cohort (14 patients and 30 specimens). BN.1 PRNT was conducted for one- and three-months after tixagevimab/ cilgavimab administration and the average PRNT ND 50 of each point was lower than the positive cut-off value of 20 (12.9 ± 4.5 and 13.2 ± 4.2, respectively, P = 0.825). In the paired analyses, tixagevimab/cilgavimab-administered sera could not actively neutralize BN.1 (PRNT ND 50 11.5 ± 2.9, P = 0.001), compared with the reserved activity against BA.5 (ND 50 310.5 ± 180.4). Unlike virus-like particle assay, tixagevimab/cilgavimab was not active against BN.1 in neutralizing assay, and would not be effective in the present predominance of BA.2.75 sublineages.
ABSTRACT
Objectives@#This study introduced a novel Automatic Needle Destroyer (AND) to an emergency department (ED) and assessed its effect on healthcare providers’ work. @*Methods@#Between August and September 2019, in the ED of a tertiary hospital in Seoul, we conducted a mixed-methods study to evaluate the efficiency, safety, and usability of the AND using video analysis, surveys, and in-depth interviews, wherein participants described the advantages and disadvantages of the AND. @*Results@#Compared to the existing method, introducing the AND significantly reduced the operating time from 2.32 ± 1.14 seconds to 1.77 ± 3.71 seconds (p < 0.001). The normal operation rate was 90.6%. The rate of needle-stick injuries (NSIs) and the mean system usability scale (SUS) showed no significant differences. The in-depth interviews indicated that the disadvantages of the AND were mostly operational. The advantages were related to profit, reduced direct contact with hazardous waste, and behavioral changes, such as not having to recap syringes. @*Conclusions@#We introduced the AND to an ED environment, where NSIs occur frequently and many syringes are used, to evaluate its effect on providers’ work. The AND reduced the time for needle disposal, but the normal operation rate was low. No significant differences were found in the SUS score or the rate of NSIs. Although there are some restrictions on introducing the AND immediately, this study’s results showed its potential usefulness. Efforts to improve the operation of the device and a longer study period are needed to fully achieve safety and efficiency.
ABSTRACT
Purpose@#Real-world experience with tocilizumab in combination with dexamethasone in patients with severe coronavirus disease (COVID-19) needs to be investigated. @*Materials and Methods@#A retrospective cohort study was conducted to evaluate the effect of severity-adjusted dosing of dexamethasone in combination with tocilizumab for severe COVID-19 from August 2020 to August 2021. The primary endpoint was 30-day clinical recovery, which was defined as no oxygen requirement or referral after recovery. @*Results@#A total of 66 patients were evaluated, including 33 patients in the dexamethasone (Dexa) group and 33 patients in the dexamethasone plus tocilizumab (DexaToci) group. The DexaToci group showed a statistically significant benefit in 30-day clinical recovery, compared to the Dexa group (p=0.024). In multivariable analyses, peak FiO2 within 3 days and tocilizumab combination were consistently significant for 30-day recovery (all p<0.05). The DexaToci group showed a significantly steeper decrease in FiO2 (-4.2±2.6) than the Dexa group (−2.7±2.6; p=0.021) by hospital day 15. The duration of oxygen requirement was significantly shorter in the DexaToci group than the Dexa group (median, 10.0 days vs. 17.0 days; p=0.006). Infectious complications and cellular and humoral immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the convalescence stage were not different between the two groups. @*Conclusion@#A combination of severity-adjusted dexamethasone and tocilizumab for the treatment of severe COVID-19 improved clinical recovery without increasing infectious complications or hindering the immune response against SARS-CoV-2.
ABSTRACT
Coronavirus disease 2019 (COVID-19) outbreak is spreading rapidly all over the world, being a major threat to public health. Since clinical feature of COVID-19 has not been fully evaluated yet, empirical antibacterial agents are frequently combined for the treatment of COVID-19 in addition to antiviral agents, concerning co-existing bacterial pathogens. We experienced a case of severe thrombocytopenia with epistaxis and petechiae, while treating a COVID-19 patient with ceftriaxone, levofloxacin, and lopinavir/ritonavir. The platelet count decreased to 2,000/mm 3 and recovered after discontinuation of the three suspected drugs. In treating a potentially fatal emerging infectious disease, empirical and/or experimental approach would be unavoidable. However, the present case suggests that the possibility of adverse effects caused by polypharmacy should also be carefully considered.
ABSTRACT
Background@#Cancer patients can be at a higher risk of infection due to drug-resistant bacteria than the general population for various reasons. We performed a retrospective study to evaluate possible risk factors and outcomes of extended-spectrum beta-lactamaseproducing Klebsiella pneumoniae (ESBL-KP) bacteremia in cancer patients. @*Materials and Methods@#Cases were divided into two groups based on whether or not the isolated strain produced ESBL and multivariable regressions were done to identify possible risk factors of ESBL-KP bacteremia and mortality. For ESBL-producing strain, additional molecular analysis was done. @*Results@#278 cases with KP bacteremia were identified between 2010 and 2012, of which ESBLproducers were 50 (18%). The presence of percutaneous drainage catheter [odds ratio (OR) 4.99, P <0.001] and prior exposure to certain classes of antibiotics including third-generation cephalosporin (OR 2.14, P = 0.03) had significant associations with ESBL-KP bacteremia. Individuals who died within 14 days after the onset of KP bacteremia were more likely to have higher mean Pitt bacteremia score (1.56 in survival group vs. 3.43 in mortality group, P <0.001), hemodialysis (OR 17.03, P = 0.01) and chronic liver disease (OR 5.57, P = 0.01). Although 14-day mortality was higher with ESBL production (OR 2.76, P = 0.04), no significant differences in 30-day mortality (OR 1.67, P = 0.20) and other morbidity indices were observed. 49 ESBL-KP isolates, 65.4% of them produced CTX-M-14 and CTX-M-15 enzymes, and ST711 was the most common. @*Conclusion@#There were several differences in clinical characteristics between ESBL-KP and nonESBL-KP bacteremia in cancer patients, similar to previous reports including non-cancer patients.
ABSTRACT
The area of endoscopic application has been continuously expanded since its introduction in the last century and the frequency of its use also increased stiffly in the last decades. Because gastrointestinal endoscopy is naturally exposed to diseased internal organs and contact with pathogenic materials, endoscopy mediated infection or disease transmission becomes a major concern in this field. Gastrointestinal endoscopy is not for single use and the proper reprocessing process is a critical factor for safe and reliable endoscopy procedures. What needed in these circumstances is a practical guideline for reprocessing the endoscope and its accessories which is feasible in the real clinical field to guarantee acceptable prevention of pathogen transmission. This guideline contains principles and instructions of the reprocessing procedure according to the step by step. And it newly includes general information and updated knowledge about endoscopy-mediated infection and disinfection. Multiple societies and working groups participated to revise; Korean Association for the Study of the Liver, the Korean Society of Infectious Diseases, Korean College of Helicobacter and Upper Gastrointestinal Research, the Korean Society of Gastroenterology, Korean Society of Gastrointestinal Cancer, Korean Association for the Study of Intestinal Diseases, Korean Pancreatobiliary Association, the Korean Society of Gastrointestinal Endoscopy Nurses and Associates and Korean Society of Gastrointestinal Endoscopy. Through this cooperation, we enhanced communication and established a better concordance. We still need more researches in this field and fill up the unproven area. And our guidelines will be renewed accordingly.
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Background@#Turnaround time (TAT) is a major quality control indicator and can be defined differently depending on the starting point in the examination process. To determine effective TAT management plan, we investigated the status of TAT management in clinical laboratories in Korea. @*Methods@#A questionnaire was developed using Google web pages and a questionnaire survey was conducted at 30 clinical laboratories in laboratory medicine from September 1 to 11 in 2018. Questions were developed regarding management time, starting point standards, management goals, most problematic stages of delayed TAT, clinical measures, and shortening barriers for investigation. @*Results@#All clinical laboratories requested to undertake the survey completed the questionnaire (response rate 100%, 30/30) and answered that they were setting and managing TAT for all tests. Many laboratories (33%) set the TAT starting point as the reception stage, prior to commencing centrifugation. Of the surveyed laboratories, 37% achieved a TAT of 120 min or more for general tests, 27% met the TAT of 90 min for pre-clinic tests, and 77% met the TAT of 60 min for completion of stat tests. Most laboratories (67%) reported that the most delayed stage was pre-analysis, and 50% reported that the greatest obstacle to shortening TAT was the ratio of stat and pre-clinic tests to general tests. @*Conclusions@#The laboratories participating in this survey set a TAT based on various criteria and were performing management for TAT improvement. The results of this study can be used as basic data to guide efficient TAT management.
ABSTRACT
Background@#Turnaround time (TAT) is a major quality control indicator and can be defined differently depending on the starting point in the examination process. To determine effective TAT management plan, we investigated the status of TAT management in clinical laboratories in Korea. @*Methods@#A questionnaire was developed using Google web pages and a questionnaire survey was conducted at 30 clinical laboratories in laboratory medicine from September 1 to 11 in 2018. Questions were developed regarding management time, starting point standards, management goals, most problematic stages of delayed TAT, clinical measures, and shortening barriers for investigation. @*Results@#All clinical laboratories requested to undertake the survey completed the questionnaire (response rate 100%, 30/30) and answered that they were setting and managing TAT for all tests. Many laboratories (33%) set the TAT starting point as the reception stage, prior to commencing centrifugation. Of the surveyed laboratories, 37% achieved a TAT of 120 min or more for general tests, 27% met the TAT of 90 min for pre-clinic tests, and 77% met the TAT of 60 min for completion of stat tests. Most laboratories (67%) reported that the most delayed stage was pre-analysis, and 50% reported that the greatest obstacle to shortening TAT was the ratio of stat and pre-clinic tests to general tests. @*Conclusions@#The laboratories participating in this survey set a TAT based on various criteria and were performing management for TAT improvement. The results of this study can be used as basic data to guide efficient TAT management.
ABSTRACT
No abstract available.
Subject(s)
Acute Kidney Injury , Hepcidins , Inflammation , Iron , Lipocalins , Metabolism , NeutrophilsABSTRACT
As 16S ribosomal RNA (rRNA)-targeted sequencing can detect DNA from non-viable bacteria, it can be used to identify pathogens from clinical samples even in patients pretreated with antibiotics. We compared the results of 16S rRNA-targeted sequencing and culture for identifying bacterial species in normally sterile body fluid (NSBF): cerebrospinal, pericardial, peritoneal and pleural fluids. Over a 10-year period, a total of 312 NSBF samples were evaluated simultaneously using 16S rRNA-targeted sequencing and culture. Results were concordant in 287/312 (92.0%) samples, including 277 (88.8%) negative and 10 (3.2%) positive samples. Of the 16 sequencing-positive, culture-negative samples, eight showed clinically relevant isolates that included Fusobacterium nucleatum subsp. nucleatum, Streptococcus pneumoniae, and Staphylococcus spp. All these samples were obtained from the patients pretreated with antibiotics. The diagnostic yield of 16S rRNA-targeted sequencing combined with culture was 11.2%, while that of culture alone was 6.1%. 16S rRNA-targeted sequencing in conjunction with culture could be useful for identifying bacteria in NSBF samples, especially when patients have been pretreated with antibiotics and when anaerobic infection is suspected.
Subject(s)
Humans , Anti-Bacterial Agents , Bacteria , Body Fluids , DNA , Fusobacterium nucleatum , RNA, Ribosomal, 16S , Staphylococcus , Streptococcus pneumoniaeABSTRACT
We implemented a carbapenem-saving strategy in hemato-oncology patients from 2013, using an empirical combination of piperacillin-tazobactam and amikacin for high-risk hemato-oncology patients with febrile neutropenia, who remain hemodynamically unstable > 72 hours despite initial cefepime treatment. All-cause mortality was not different between the two periods (6.54 and 6.57 deaths per 1,000 person-day, P = 0.926). Group 2 carbapenem use significantly decreased after strategy implementation (78.43 vs. 67.43 monthly days of therapy, P = 0.018), while carbapenem-resistant gram-negative bacilli did not show meaningful changes during the study period. Our carbapenem-saving strategy could effectively suppress carbapenem use without an increase of overall mortality.
Subject(s)
Humans , Amikacin , Febrile Neutropenia , MortalityABSTRACT
Catabacter hongkongensis is an anaerobic gram-positive coccobacillus that was first isolated in Hong Kong. It is infectious and causes high mortality in patients with rare but underlying diseases. Alistipes indistinctus is an anaerobic gram-negative coccobacillus. This bacterium is a common member of the human intestinal microbiota. We report a case of C. hongkongensis and A. indistinctus isolated from blood cultures of a patient with acute appendicitis. A 35-year-old female patient with no specific medical history was admitted to the hospital due to abdominal pain, vomiting, nausea, and diarrhea experienced on the day before admission. On admission, laboratory tests revealed leukocytosis, neutropenia, and elevated C–reactive protein and procalcitonin levels. Following an abdominal computed tomography showing acute appendicitis with suspected perforation, emergency surgery was performed. Growth was observed in two anaerobic blood culture bottles after four days. After further culturing of the bacteria on Brucella Blood Agar, two types of bacteria were obtained. The two bacterial isolates, one gram-positive and one gram-negative, were unable to be identified using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Thus, 16S rRNA gene sequence analysis was performed, resulting in identification of the bacteria as C. hongkongensis and A. indistinctus. The patient was administered antibiotics and discharged two days after surgery. Although MALDI-TOF MS enables fast and accurate identification of bacteria, C. hongkongensis and A. indistinctus were not listed in the spectral library, and 16S rRNA gene sequence analysis was useful for identifying the two bacteria.
Subject(s)
Adult , Female , Humans , Abdominal Pain , Agar , Anti-Bacterial Agents , Appendicitis , Bacteria , Brucella , Diarrhea , Emergencies , Gastrointestinal Microbiome , Genes, rRNA , Hong Kong , Leukocytosis , Mass Spectrometry , Mortality , Nausea , Neutropenia , Sequence Analysis , VomitingABSTRACT
BACKGROUND: Rotavirus is a major pathogen causing enteritis worldwide in children under five years of age. In recent years, immunochromatographic assay (ICA) has been widely used as a diagnostic test for rotavirus detection. This study aimed to compare and evaluate the performance of ICA-based rotavirus rapid test kits from two manufacturers. METHODS: Residual stool samples from a total of 130 children with acute enterocolitis from November 2017 to January 2018 were used. We compared the results of the two immunochromatographic methods (SD BIOLINE Rotavirus kit and GENEDIA Rotavirus Ag Rapid Test) with those of the currently used enzyme immunoassay method. RESULTS: Positive agreement, negative agreement, and total agreement rates between the SD BIOLINE rotavirus kit and the enzyme immunoassay were 98.0%, 100%, and 99.2%, respectively. Positive agreement, negative agreement, and total agreement rates between the GENEDIA Rotavirus Ag Rapid Test and the enzyme immunoassay were 96.0%, 100%, and 98.4%, respectively. CONCLUSIONS: Both rotavirus rapid test kits showed very good agreement with the conventional enzyme immunoassay. Therefore, it could be a useful test to detect rotavirus directly from stool samples in a short time.
Subject(s)
Child , Humans , Diagnostic Tests, Routine , Enteritis , Enterocolitis , Chromatography, Affinity , Immunoenzyme Techniques , Methods , RotavirusABSTRACT
BACKGROUND: Optimal tacrolimus (TAC) trough levels for different periods after kidney transplantation (KT) has not been definitely established. This study aimed to investigate transplant outcomes of low-level (LL) and standard-level (SL) TAC according to post-transplant period. METHODS: A total of 278 consecutive kidney transplant recipients (KTRs) receiving TAC-based immunosuppression were divided into LL and SL-TAC groups (4–7 and 7–12 ng/mL for 0–2 months, 3–6 and 6–10 ng/mL for 3–6 months, 2–5 and 5–8 ng/mL for 7–12 months, respectively) according to TAC trough level at each period. We compared estimated glomerular filtration rate (eGFR), biopsy-proven acute rejection (BPAR), de novo donor-specific antibody (dnDSA), calcineurin inhibitor (CNI) toxicity, opportunistic infection, and allograft survival. RESULTS: SL-TAC group showed significantly higher mean eGFR at 0–2 months than LL-TAC group (72.1 ± 20.3 vs. 64.2 ± 22.7 mL/min/1.73m2; P = 0.003). Incidence of BPAR at 7–12 months was significantly lower in SL-TAC group than in LL-TAC group (0.0% vs. 3.9%; P = 0.039). Patients with persistent SL-TAC lasting 12 months showed higher eGFR at 7–12 months than those with persistent LL-TAC (65.5 ± 13.0 vs. 57.9 ± 13.9 mL/min/1.73m2; P = 0.007). No significant differences in dnDSA, CNI toxicity, serious infections, or allograft survival were observed. CONCLUSIONS: Maintenance of proper TAC trough level after 6 months could reduce BPAR without adverse drug toxicities in KTRs. Moreover, persistent SL-TAC during the first year after KT might have a beneficial effect on a trend for a lower incidence of dnDSA and better renal allograft function.
Subject(s)
Humans , Allografts , Calcineurin , Drug-Related Side Effects and Adverse Reactions , Glomerular Filtration Rate , Immunosuppression Therapy , Incidence , Kidney Transplantation , Kidney , Opportunistic Infections , Tacrolimus , Transplant RecipientsABSTRACT
BACKGROUND: The association of de novo donor-specific anti-human leukocyte antigens (HLA) antibodies (DSA) and development of antibody-mediated rejection (AMR) in kidney transplant recipients (KTRs) is still undetermined. METHODS: We prospectively screened de novo DSA in 167 KTRs during 32 months after kidney transplantation (KT). Timing of DSA detection was at 3, 6, and 12 months post-transplant and annually thereafter and when clinically indicated. DSA levels were determined by Luminex assays and expressed as mean fluorescence intensity (MFI). We evaluated the incidence, characteristics of DSA, and association between DSA and tacrolimus trough levels or AMR. RESULTS: De novo DSA developed in 16 KTRs (9.6%) and acute AMR occurred more commonly in KTRs with de novo DSA compared to KTRs without de novo DSA (18.8% vs. 0%, P < 0.001). All de novo DSA were against class II antigens. The mean number of DSA was 1.8 ± 1.2 and the average MFI of DSA was 7,399 ± 5,470. Tacrolimus trough level during the first 0–2 months after KT was an independent predictor of DSA development (hazard ratio, 0.70; 95% confidence interval, 0.50–0.99; P = 0.043). No differences were found in the number of DSA, average MFI of DSA, and tacrolimus levels during the first year between de novo DSA-positive KTRs with AMR and those without AMR. CONCLUSION: The results of our study suggest that monitoring of DSA and maintaining proper tacrolimus levels are essential to prevent AMR during the initial period after KT.
Subject(s)
Antibodies , Fluorescence , Graft Rejection , Histocompatibility Antigens Class II , HLA Antigens , Incidence , Kidney Transplantation , Kidney , Prospective Studies , Tacrolimus , Transplant RecipientsABSTRACT
No abstract available.
Subject(s)
Biomarkers , Carrier Proteins , Glycosylation , Liver Cirrhosis , LiverABSTRACT
PURPOSE: Tuberculosis (TB) is one of the most important diseases that cause significant mortality and morbidity in young children. Data on TB transmission from an infected child are limited. Herein, we report a case of disseminated TB in a child and conducted a contact investigation among exposed individuals. METHODS: A 4-year-old child without Bacille Calmette-Guérin vaccination was diagnosed as having culture-proven disseminated TB. The child initially presented with symptoms of inflammatory bowel disease, and nosocomial and kindergarten exposures were reported. The exposed individuals to the index case were divided into 3 groups, namely household, nosocomial, or kindergarten contacts. Evaluation was performed following the Korean guidelines for TB. Kindergarten contacts were further divided into close or casual contacts. Chest radiography and tuberculin skin test or interferon-gamma-releasing assay were performed for the contacts. RESULTS: We examined 327 individuals (3 household, 10 nosocomial, and 314 kindergarten contacts), of whom 18 (5.5%), the brother of the index patient, and 17 kindergarten children were diagnosed as having latent TB infection (LTBI). LTBI diagnosis was more frequent in the children who had close kindergarten contact with the index case (17.1% vs. 4.4%, P=0.007). None of the cases had active TB. CONCLUSION: This is the first reported case of TB transmission among young children from a pediatric patient with disseminated TB in Korea. TB should be emphasized as a possible cause of chronic diarrhea and failure to thrive in children. A national TB control policy has been actively applied to identify Korean children with LTBI.