Submandibular Injury Caused by the Close-Range Firing of a Military Blank Cartridge Shot

Few studies have reported injuries caused by a blank cartridge shot (BCS) into the head and neck. We experienced a case of minor injury resulting from BCS (despite the close proximity). The patient was a 20-year-old male soldier who attempted suicide by firing a BCS from a K2 rifle into his mouth. He suffered from skin and soft tissue defect in the submandibular area with burns and minimal bleeding. A computed tomography scan showed subcutaneous emphysema which was suspected to be related to the projectile gas released during the firing of the BCS, and a tiny fragment without hematoma or structure injuries. We closely observed the clinical features including the occurrence of infection and functional abnormalities. The subcutaneous emphysema faded away along with the soft tissue defect. After wound management was completed on the 13th hospital day, the patient was transferred to the Department of Psychiatry without any problems.

Predicting Phenotypic Antimicrobial Resistance in Escherichia coli Isolates, Using Whole Genome Sequencing Data / 대한임상미생물학회지

Background@#The application of genotypic antimicrobial sensitivity tests (ASTs) is dependent on the reliability of the predictions of phenotypic resistance. In this study, routine AST results and the presence of corresponding antimicrobial resistance genes were compared. @*Methods@#Eighty-four extended-spectrum-β-lactamase-producing Escherichia coli isolates from poultry-related samples were included in the study. The disk diffusion method was used to test for susceptibility to antimicrobial compounds, except colistin susceptibility, which was tested using the agar dilution method. Whole-genome sequencing (WGS) was performed using a NextSeq 550 instrument (Illumina, USA). Antimicrobial resistance genes were detected using ResFinder 4.1. @*Results@#Concordance rates between the genotype and phenotype ranged from 35.7% (ciprofloxacin) to 96.4% (tetracycline). The presence of tet was a good predictor of phenotypic resistance. @*Conclusion@#The genotype was a good predictor of tetracycline phenotypic resistance, but there was a gap in the prediction of phenotypic ASTs for trimethoprim-sulfamethoxazole, chloramphenicol, gentamicin, and ciprofloxacin. We concluded that WGS-based genotypic ASTs are inadequate to replace routine phenotypic ASTs.

A Retrospective National Study on Colonization Rate and Antimicrobial Susceptibility of Streptococcus agalactiae in Pregnant Korean Women, 2018–2020

Purpose@#The prevalence of Group B Streptococcus (GBS) colonization in pregnant Korean women is increasing; however, nationwide studies are lacking. Therefore, we aimed to analyze regional colonization rates and antimicrobial susceptibility for GBS in pregnant Korean women through a nationwide survey. @*Materials and Methods@#From January 2018 to December 2020, data from the Seoul Clinical Laboratories on vaginal swab cultures were retrospectively analyzed to detect maternal GBS carriers. Each swab specimen was inoculated onto a 5% blood agar plate and incubated at 35°C–37°C in a 5% CO 2 incubator for 24 h. GBS isolates were identified using a Microflex MALDI Biotyper. Antimicrobial susceptibility tests were performed using the Vitek 2 automated system. @*Results@#The overall nationwide GBS colonization rate in pregnant Korean women was found to be 10.6% (3578/33721). The maternal GBS colonization rates ranged from 10.5%–10.8% over the 3-year study period. The GBS colonization rates by province, in descending order, were as follows: Jeolla-do, 13.2%; Gangwon-do, 12.0%; Chungcheong-do, 11.8%; Gyeonggi-do, 11.3%; Seoul, 10.2%; and Gyeongsang-do, 9.6%. During the study period, the resistance rates against chloramphenicol, levofloxacin, clindamycin, erythromycin, and tetracycline were 2.6%–2.7%, 18.2%–19.6%, 33.4%–35.7%, 35.6%–36.8%, and 50.5%–53.3%, respectively. @*Conclusion@#In pregnant Korean women, GBS colonization rates were in the range of 9.6%–13.2%, with Gyeongsang-do being the lowest and Jeolla-do the highest. The resistance rate against clindamycin was high (33.4%–35.7%). GBS colonization rates during pregnancy should be studied nationwide according to the Centers for Disease Control and Prevention-recommended guidelines with periodic antimicrobial resistance monitoring.

Trends in Isolation and Antimicrobial Susceptibility of Enteropathogenic Bacteria in 2011-2019 at a Korean Tertiary Care Hospital Compared with Data in the Preceding Reports / 대한임상미생물학회지

Background@#Environmental sanitation plays a significant role on the prevalence of enteropathogenic bacteria. This study aimed to determine the trends in the prevalence and antimicrobial resistance profiles of enteropathogenic bacteria from 2011 to 2019. @*Methods@#A retrospective analysis was performed using data from stool cultures of Salmonella spp., Shigella spp., Plesiomonas shigelloides , Yersinia spp., Vibrio spp., and Campylobacter spp. Samples were obtained between 2011 and 2019 from Severance Hospital. Antimicrobial susceptibility profile was determined using the disk diffusion method for nontyphoidal Salmonella (NTS) and Campylobacterspp., following the Clinical and Laboratory Standards Institute (CLSI) guidelines. @*Results@#The number of specimens obtained for stool culture increased significantly from 13,412 during the period of 1969–1978, to 48,476 over the past nine years (2011–2019), whereas the ratio of positive specimens decreased significantly from 1,732 (12.9%) to 449 (0.9%). The proportion of samples positive for Salmonella Typhi decreased from 472 (93.6%, 1969–1978) to 4 (1.5%, 2011–2019), whereas the proportion of NTS increased from 14 (2.8%, 1969–1978) to 261 (96.7%, 2011–2019). Among all the enteropathogenic bacteria isolated, Shigella spp. accounted for 60.0% (1,039) isolates from 1969 to 1978, but only 1.6% (7) from 2011 to 2019. Campylobacter was the second most prevalent enteropathogenic bacteria, accounting for 29.4% isolates (132). Among the NTS strains isolated from 2016 to 2019, their susceptibility rates to ampicillin and sulfamethoxazole-trimethoprim were 51.1% and 85.2%, respectively. Additionally, the susceptibility rate of Campylobacter to ciprofloxacin was 15.8%. @*Conclusion@#The prevalence of Salmonella Typhi and Shigella spp. significantly decreased, whereas those of NTS and Campylobacter spp. increased. Therefore, continuous monitoring of ciprofloxacin-resistant Campylobacter spp. is of vital importance.

Prevalence and Molecular Epidemiology of ExtendedSpectrum-β-Lactamase (ESBL)-Producing Escherichia coli From Multiple Sectors of the Swine Industry in Korea: A Korean Nationwide Monitoring Program for a One Health Approach to Combat Antimicrobial Resistance

Background@#One health is a flexible concept with many facets, including the environment, community, and the nosocomial super-bacteria resistance network. We investigated the molecular prevalence of extended-spectrum-β-lactamase-producing Escherichia coli (ESBL-EC) in workers, livestock, and the farm environment in Korea. @*Methods@#ESBL-EC isolates were obtained from samples from 19 swine farms, 35 retail stores, seven slaughterhouses, and 45 related workers throughout Korea from August 2017 to July 2018, using ChromID ESBL (BioMérieux, Marcy l’Etoile, France) agar and enrichment broth. The presence of ESBL and mobilized colistin resistance (mcr) genes and antimicrobial resistance were determined. Clonality was evaluated with pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). @*Results@#In total, 232 ESBL-EC isolates were obtained from 1,614 non-duplicated samples (14.4% positive rate). The ESBL-EC isolates showed regional and source-related differences. blaCTX-M-55 (N = 100), blaCTX-M-14 (N = 65), blaCTX-M-15 (N = 33), and blaCTX-M-65 (N = 23) were common ESBL types. The ESBL-EC isolates showed high resistance rates for various antimicrobial classes; however, all isolates were susceptible to carbapenem. One swine-originating colistin-resistant isolate did not carry any known mcr gene. PFGE was successful for 197 of the 232 isolates, and most PFGE types were heterogeneous, except for some dominant PFGE types (O, R, T, U, and V). MLST of 88 isolates was performed for representative PFGE types; however, no dominant sequence type was observed. @*Conclusions@#The proportion of ESBL-EC in swine industry-related samples was significant, and the isolates harbored common clinical ESBL gene types. These molecular epidemiologic data could provide important evidence for antimicrobial-resistance control through a one health approach.

Risk Factors Associated with Recurrent Urinary Tract Infection Caused by Escherichia coli / 대한임상미생물학회지

Background@#The purpose of this study was to analyze the clinical and microbiological characteristics of recurrent urinary tract infection (UTI) caused by Escherichia coli— the most common etiological agent. @*Methods@#Cases of recurrent and single episodes of UTI caused by E. coli were evaluated retrospectively for a period of 6 months (January-June 2019) to analyze the clinical and molecular characteristics of this disease. @*Results@#Healthcare-associated UTI, E. coli bacteremia, and poor microbial clearance 7 days post infection were associated more with the recurrent episodes of infection. E. coli isolates from subjects with recurrent UTIs showed higher rates of antimicrobial resistance and extended-spectrum β-lactamase (ESBL) production. The E. coli clone— sequence type 131 was detected in similar proportions in isolates, recovered from subjects in both groups— recurrent episodes and single episode of UTI. @*Conclusion@#The control of antimicrobial-resistant ESBL-producing E. coli strains may be difficult using antimicrobial therapy and subsequently delay the clearance of the etiologic agent. This could play a major role in the development of recurrent UTIs.

Isolation of Non-Hydrogen Sulfide-Producing Salmonella enterica Serovar Infantis from a Clinical Sample: the First Case in Korea

No abstract available.

Season and Temperature Effects on Bloodstream Infection Incidence in a Korean Tertiary Referral Hospital / 대한임상미생물학회지

BACKGROUND: The weather has well-documented effects on infectious disease and reports suggest that summer peaks in the incidences of gram-negative bacterial infections among hospitalized patients. We evaluated how season and temperature changes affect bloodstream infection (BSI) incidences of major pathogens to understand BSI trends with an emphasis on acquisition sites.METHODS: Incidence rates of BSIs by Staphylococcus aureus, Enterococcus spp., Escherichia coli, Klebsiella pneumoniae, Acinetobacter spp., and Pseudomonas aeruginosa were retrospectively analyzed from blood cultures during 2008–2016 at a university hospital in Seoul, Korea according to the acquisition sites. Warm months (June–September) had an average temperature of ≥20℃ and cold months (December–February) had an average temperature of ≤5℃.RESULTS: We analyzed 18,047 cases, where 43% were with community-onset BSI. E. coli (N = 5,365) was the most common pathogen, followed by Enterococcus spp. (N = 3,980), S. aureus (N = 3,075), K. pneumoniae (N = 3,043), Acinetobacter spp. (N = 1,657), and P. aeruginosa (N = 927). The incidence of hospital-acquired BSI by Enterococcus spp. was weakly correlated with temperature, and the median incidence was higher during cold months. The incidence of community-onset BSI by E. coli was higher in warm months and was weakly correlated with temperature.CONCLUSION: We found seasonal or temperature-associated variation in some species-associated BSIs. This could be a useful information for enhancing infection control and public health policies by taking season or climate into consideration.

Prevalence and Risk Factors for Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae Colonization in Intensive Care Units

Active surveillance culture (ASC) can help detect hidden reservoirs, but the routine use of ASC for extended spectrum β-lactamase-producing Enterobacteriaceae is controversial in an endemic situation. We aimed to determine the prevalence and risk factors of extended spectrum β-lactamase-producing Klebsiella pneumoniae (EBSL-Kpn) colonization among intensive care unit (ICU)-admitted patients. Prospective screening of ESBL-Kpn colonization was performed for ICU-admitted patients within 48 hours for two months. A perirectal swab sample was inoculated on MacConkey agar supplemented with 2 µg/mL ceftazidime. ESBL genotype was determined by PCR-sequencing, and clonal relatedness was evaluated by pulsed-field gel electrophoresis (PFGE). The risk factors of ESBL-Kpn colonization were evaluated. The ESBL-Kpn colonization rate among the 281 patients at ICU admission was 6.4% (18/281), and bla(CTX-M-15) was detected in all isolates. ESBL producers also showed resistance to fluoroquinolone (38.9%, 7/18). All isolates had the same ESBL genotype (bla(CTX-M-15)) and a highly clustered PFGE pattern, suggesting cross-transmission without a documented outbreak. In univariate analysis, the risk factor for ESBL-Kpn colonization over the control was the length of hospital stay (odds ratio=1.062; P=0.019). Routine use of ASC could help control endemic ESBL–Kpn for ICU patients.

Whole-Genome Analysis of bla(CTX-M-55)-Carrying Escherichia coli Among Pigs, Farm Environment, and Farm Workers

No abstract available.

Characteristics of Faecal Microbiota in Korean Patients with Clostridioides difficile-associated Diarrhea

BACKGROUND@#The intestinal microbiota plays an important role in the pathogenesis of Clostridioides difficile-associated diarrhea, and regional and racial characteristics influence the microbiome composition and diversity. We investigated the intestinal microbiome characteristics of patients with C. difficile colitis (CD+) compared to those of patients with colitis not due to C. difficile (CD−), patients with vancomycin-resistant enterococci (VRE) colonization, and healthy controls, in Korea.@*MATERIALS AND METHODS@#We collected stool samples from 24, 18, 11 and 13 subjects within CD+, CD−, VRE and healthy control groups, respectively. The microbial communities were evaluated by 454-pyrosequencing of bacterial 16s rRNA.@*RESULTS@#The species richness and microbial diversity were significantly lower in the CD+ group compared to those in healthy controls, but not compared to those in CD− and VRE groups. Phylum-level analysis showed that the proportion of Actinobacteria in the CD+ group was significantly lower than in the healthy control, but was unchanged compared to that in CD− and VRE groups. At the genus level, compared to the healthy group, the CD+ group showed significantly lower proportions of Blautia, Bifidobacterium, Faecalibacterium et al. Compared to the VRE group, the CD+ group showed a significantly higher proportion of Anaerostipes.@*CONCLUSIONS@#We could identify the intestinal microbiome characteristics of Koreans with C. difficile colitis. It might help to develop microbiome based diagnostic and treatment modalities.

Septicemia Caused by Herbaspirillum huttiense Secondary to Pneumonia

No abstract available.

First Case of Trueperella bernardiae Bacteremia in an Immunocompromised Patient in Korea

No abstract available.

Recent Increase in the Incidence of TEM-135 β-Lactamase-harboring Neisseria gonorrhoeae in Korea

BACKGROUND: We investigated the molecular epidemiological characteristics and antimicrobial susceptibility pattern of penicillinase-producing Neisseria gonorrhoeae (PPNG) isolates to monitor the change in distribution of bla(TEM) in Korea. METHODS: We collected 804 PPNG isolates from diverse hospitals and clinics mainly located in Seoul, Korea, over a period of 11 years (2005–2015). Isolate susceptibility to seven antimicrobials was determined using the agar dilution test. The molecular epidemiological characteristics of the isolates were determined by Sanger sequencing of bla(TEM), N. gonorrhoeae multiantigen sequence typing (NG-MAST) and plasmid typing. RESULTS: Among 72 fully sequenced PPNG isolates, sixteen (22.2%) possessed TEM-135. All TEM-135 isolates had a common silent mutation (c.18C>T), which was previously unreported. We observed a pattern of continuous increase in the number of TEM-135 isolates since 2012. The median and 90% minimum inhibitory concentration of azithromycin were substantially lower in the TEM-135 group than in the non-PPNG and TEM-1 groups. All TEM-135 isolates showed different NG-MAST types and predominantly harbored Toronto/Rio (75%) plasmids. A comprehensive comparative analysis of PPNG with TEM-135 according to NG-MAST, plasmid type, and year of isolation revealed a wide distribution. CONCLUSIONS: The proportion of TEM-135 PPNG has continuously increased since 2012, in association with clonal spread. The difference at position 18 of the TEM-135 sequence can be interpreted as the existence of multiple clonal complexes. The possibility that TEM-135 was acquired via foreign plasmids requires careful follow-up and continuous monitoring of TEM-135 to ascertain whether it constitutes a step towards evolutionary change.

The Usefulness of Active Surveillance Culture of Extended-Spectrum β-Lactamase-Producing Escherichia coli in ICU Settings without Outbreak in the Situation of Wide Spread of Sequence Type 131 ESBL-Producing E. coli in Community / 대한임상미생물학회지

BACKGROUND: In the present study, the prevalence and risk factors for acquisition of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in intensive care unit (ICU) settings without outbreak in the situation of widespread sequence type (ST) 131 ESBL-producing E. coli in a Korean community was investigated. METHODS: Consecutive and prospective screening of ESBL-producing E. coli colonization was performed in all patients admitted to surgical or medical ICUs within 48 hours for two months. ESBL genotype was determined based on PCR and sequencing. PCR for O16-ST131/O25-ST131 was performed for all ESBL producers. Clinical information was obtained from a review of electronic medical record to determine the risk factors for ESBL-producing E. coli colonization. RESULTS: The colonization rate of ESBL-producing E. coli at ICU admission was 14.9% (42/281). CTX-M-15 (N=15), CTX-M-14 (N=12), and CTX-M-27 (N=10) were commonly detected using PCR of ESBL genes. Approximately half (45.2%, 19/42) of ESBL producers were ST131 clone with 14 ST131-O25 and 5 ST131-O16. In univariate analysis, independent risk factor for acquisition of ESBL-producing E. coli compared with controls was ICU type (odds ratio, 2.05; P < 0.032); however, site of acquisition, previous antibiotic use, and hospital stay were not significant risk factors. CONCLUSION: In this study, the colonization of ESBL-producing E. coli at ICU admission without outbreak was frequent and it could be an infection source, regardless of acquisition site. We recommend routine use of ASC to control endemic ESBL-producing E. coli considering the wide distribution of ST131-ESBL-producing E. coli in the Korean community.

Performance of Microflex LT Biotyper and VITEK MS for Routine Identification of Yeasts

No abstract available.

An Imported Case of Brucella melitensis Infection in South Korea

Brucellosis is a zoonotic infection that is usually transmitted from cattle to humans through ingestion of animal milk, direct contact with animal parts, or inhalation of aerosolized particles. In Korea, brucellosis seem to be transmitted through close contact with blood, fetus, urine, and placenta of domestic cow that has been infected by Brucella abortus, or inhalation of B. arbortus while examining or slaughtering cow. Brucella melitensis infection is rare in Korea and there have been no reported cases of B. melitensis originating from other countries until now. This report details a case of complicated brucellosis with infective spondylitis in a 48-year-old male construction worker recently returned from Iraq. Infection with B. melitensis was confirmed using 16s rRNA sequencing and omp31 gene analysis. The patient was successfully treated using a combination of rifampin, doxycycline, and streptomycin, in accordance with WHO guidelines. This is the first reported case of complicated brucellosis with infective spondylitis in Korea caused by B. melitensis originating from Iraq.

An Imported Case of Brucella melitensis Infection in South Korea

Brucellosis is a zoonotic infection that is usually transmitted from cattle to humans through ingestion of animal milk, direct contact with animal parts, or inhalation of aerosolized particles. In Korea, brucellosis seem to be transmitted through close contact with blood, fetus, urine, and placenta of domestic cow that has been infected by Brucella abortus, or inhalation of B. arbortus while examining or slaughtering cow. Brucella melitensis infection is rare in Korea and there have been no reported cases of B. melitensis originating from other countries until now. This report details a case of complicated brucellosis with infective spondylitis in a 48-year-old male construction worker recently returned from Iraq. Infection with B. melitensis was confirmed using 16s rRNA sequencing and omp31 gene analysis. The patient was successfully treated using a combination of rifampin, doxycycline, and streptomycin, in accordance with WHO guidelines. This is the first reported case of complicated brucellosis with infective spondylitis in Korea caused by B. melitensis originating from Iraq.

Same-Day Identification and Antimicrobial Susceptibility Testing of Bacteria in Positive Blood Culture Broths Using Short-Term Incubation on Solid Medium with the MicroFlex LT, Vitek-MS, and Vitek2 Systems

BACKGROUND: Early and appropriate antibiotic treatment improves the clinical outcome of patients with septicemia; therefore, reducing the turn-around time for identification (ID) and antimicrobial susceptibility test (AST) results is essential. We established a method for rapid ID and AST using short-term incubation of positive blood culture broth samples on solid media, and evaluated its performance relative to that of the conventional method using two rapid ID systems and a rapid AST method. METHODS: A total of 254 mono-microbial samples were included. Positive blood culture samples were incubated on blood agar plates for six hours and identified by the MicroFlex LT (Bruker Daltonics) and Vitek-MS (bioMeriéux) systems, followed by AST using the Vitek2 System (bioMeriéux). RESULTS: The correct species-level ID rates were 82.3% (209/254) and 78.3% (199/254) for the MicroFlex LT and Vitek-MS platforms, respectively. For the 1,174 microorganism/antimicrobial agent combinations tested, the rapid AST method showed total concordance of 97.8% (1,148/1,174) with the conventional method, with a very major error rate of 0.5%, major error rate of 0.7%, and minor error rate of 1.0%. CONCLUSIONS: Routine implementation of this short-term incubation method could provide ID results on the day of blood culture-positivity detection and one day earlier than the conventional AST method. This simple method will be very useful for rapid ID and AST of bacteria from positive blood culture bottles in routine clinical practice.

Seasonal and Temperature-Associated Increase in Community-Onset Acinetobacter baumannii Complex Colonization or Infection

Identifying the trends in community-onset Acinetobacter baumannii complex isolation and diversity according to temperature could help provide insight into the behavior of the A. baumannii complex. We performed a retrospective analysis of A. baumannii complex (Acinetobacter baumannii, Acinetobacter nosocomialis, Acinetobacter pittii, and Acinetobacter calcoaceticus) isolates obtained from patients at a Korean community hospital from 2006 to 2015 with reference to seasonal temperatures. The incidence rates were compared between warm (June–September) and cold (November–March) months, defined as an average mean temperature ≥20℃ and ≤5℃, respectively. Incidence rate was calculated as the number of cases per month, converted to cases/10⁵ admissions for healthcare-acquired isolates and cases/10³ outpatients for community-onset isolates. Approximately 3,500 A. baumannii complex cases were identified, and 26.2% of them were community-onset cases. The median (interquartile range) number of community-onset A. baumannii complex cases was significantly higher (P=0.0002) in warm months at 13.8 (9.5–17.6) than in cold months at 10.1 (6.3–13.2). There was a strong correlation between community-onset A. baumannii complex cases and temperature (Pearson's r=0.6805, P=0.0149). Thus, we identified a seasonality pattern for community-onset A. baumannii complex colonization or infection, but not for healthcare-acquired cases.