Changing Epidemiology of Pathogenic Bacteria Over the Past 20 Years in Korea

Background@#The epidemiology of pathogenic bacteria varies according to the socioeconomic status and antimicrobial resistance status. However, longitudinal epidemiological studies to evaluate the changes in species distribution and antimicrobial susceptibility of pathogenic bacteria nationwide are lacking. We retrospectively investigated the nationwide trends in species distribution and antimicrobial susceptibility of pathogenic bacteria over the last 20 years in Korea. @*Methods@#From 1997 to 2016, annual cumulative antimicrobial susceptibility and species distribution data were collected from 12 university hospitals in five provinces and four metropolitan cities in South Korea. @*Results@#The prevalence of Staphylococcus aureus was the highest (13.1%) until 2012 but decreased to 10.3% in 2016, consistent with the decrease in oxacillin resistance from 76.1% in 2008 to 62.5% in 2016. While the cefotaxime resistance of Escherichia coli increased from 9.0% in 1997 to 34.2% in 2016, E. coli became the most common species since 2013, accounting for 14.5% of all isolates in 2016. Pseudomonas aeruginosa and Acinetobacter baumannii rose to third and fifth places in 2008 and 2010, respectively, while imipenem resistance increased from 13.9% to 30.8% and 0.7% to 73.5% during the study period, respectively.Streptococcus agalactiae became the most common pathogenic streptococcal species in 2016, as the prevalence of Streptococcus pneumoniae decreased since 2010. During the same period, pneumococcal penicillin susceptibility decreased to 79.0%, and levofloxacin susceptibility of S. agalactiae decreased to 77.1% in 2016. @*Conclusion@#The epidemiology of pathogenic bacteria has changed significantly over the past 20 years according to trends in antimicrobial resistance in Korea. Efforts to confine antimicrobial resistance would change the epidemiology of pathogenic bacteria and, consequently, the diagnosis and treatment of infectious diseases.

Cutaneous Mycobacterium massiliense Infection Caused by Skin Coining ‘Gua Sha’ in Korean Healthy Female

Nontuberculous mycobacteria are ubiquitous environmental organisms that are rare pathogens in immunocompetent individuals. However, cutaneous nontuberculous mycobacteria infections have been increasingly associated with invasive procedures, including surgery, liposuction, filler injection, intramuscular injection, mesotherapy, piercing, acupuncture, and cupping therapy. Herein, we report the first case of cutaneous nontuberculous mycobacteria infection caused by the East-Asian traditional treatment ‘Gua Sha’, also known as scraping, coining or spooning in English. A 35-year-old healthy female presented with widespread, painful skin nodules and pustules on her upper and lower extremities that had developed after Gua Sha treatment for body contouring. Histopathologic examination of the lesions revealed granulomatous inflammation in the dermis and the culture isolates were identified as Mycobacterium massiliense with molecular identification. The patient was successfully treated with intermittent incision and drainage of persistent nodules and oral clarithromycin based on antimicrobial susceptibility testing. We recommend implementation of a standard safety protocol for Gua Sha practitioners to minimize the risk of infection transmission.

First Case of Catheter-related Malassezia pachydermatis Fungemia in an Adult

No abstract available.

First Case of Aureimonas altamirensis Bacteremia in Korea

No abstract available.

Current Status of the Operations of Clinical Microbiology Laboratories at Night, on Weekends, and during Public Holidays in Korea: Proposing a Consensus Guideline

BACKGROUND: Clinical microbiological tests are conducted at night, on weekends, and during public holidays in various manners due to the fact that both manual processes and the form of working type, are not well known. Therefore, we surveyed the current running condition of these laboratories and made some suggestions for better-quality clinical microbiology tests. METHODS: We conducted a survey, both online and offline, focusing on the operating styles of clinical microbiological tests within laboratories that had participated in an external quality assessment program, conducted by the Korean Association of External Quality Assessment Service (KEQAS). RESULTS: Out of 341 laboratories that participated in the microbiology program of KEQAS, 128 replied to our questionnaires. In Korea, various types of operations occur within clinical microbiology laboratories. Those in night duty operate in either shifts or dedicated duties. In the case of weekend shifts, they either operated on single-day schedules (either on a Saturday or a Sunday), or over the entire weekend. For public holidays, the laboratories operated in various manners, depending on the number of days off. Among the clinical microbiological tests conducted at night, on weekends, and during public holidays, Gram staining and inoculations are the most common tasks carried out, with some laboratories conducting antibiotic susceptibility tests as well. CONCLUSIONS: Rapid reporting of clinical microbiological test results is currently inadequate due to both cost and labor constraints, despite its many advantages. It would be ultimately beneficial for both the patient and the hospital to switch to a 24/7 operating schedule through the utilization of a variety of methods, including cost control, coordination of a fine workforce, and prioritization of tests needing to be reported.

ABO*B3.01 Found in the A1B3 Phenotype Showing ABO Discrepancy: The First Case in Korea / 대한수혈학회지

B₃ is a rare finding, but it is most common in the B subgroup, which been reported as being 0.025% of the total B group in Koreans. ABO*B3.01 is a specific allele for B₃, a missense mutation with a substituted thymine from cytosine of the 1,054th nucleotide of the ABO*B.01 allele, but rather unexpectedly, it has not been reported in Koreans. We report here the first Korean case of the serological A₁B₃ phenotype with ABO*B3.01, which was confirmed by sequencing of exons 6 and 7 of the ABO gene, found in a pregnant woman.

Molecular Epidemiological Features and Antibiotic Susceptibility Patterns of Streptococcus dysgalactiae subsp. equisimilis Isolates from Korea and Japan

BACKGROUND: The molecular characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) has not yet been performed in Korea. This study aimed to find the differences or similarities in the clinical features, molecular epidemiological findings, and antimicrobial resistance patterns of SDSE from two countries (Korea and Japan). METHODS: SDSE isolates were collected from Korea (N=69) from 2012–2016 and Japan (N=71) from 2014–2016. Clinical characteristics, emm genotypes, and sequence types (STs) were compared. Microdilution tests were performed using different antimicrobials, and their resistance determinants were screened. RESULTS: Median ages were 69 years in Korea and 76 years in Japan. The most common underlying diseases were diabetes and malignancy. Blood-derived isolates comprised 36.2% and 50.7% of Korean and Japanese isolates, respectively; mortality was not different between the two groups (5.8% vs 9.9%, P=0.53). Among Korean isolates with 20 different combined ST-emm types, ST127-stG245 (N=16), ST128-stG485 (N=10), and ST138-stG652 (N=8) were prevalent. Among Japanese isolates with 29 different combined types, ST17-stG6792 (N=11), ST29-stG485 (N=7), and ST205-stG6792 (N=6) were prevalent. Resistance rates to erythromycin, clindamycin, and minocycline were 34.8%, 17.4%, and 30.4% in Korea and 28.2%, 14.1%, and 21.4% in Japan, respectively. CONCLUSIONS: SDSE infections commonly occurred in elderly persons with underlying diseases. There was a significant difference in the distribution of ST-emm types between the two countries. Antimicrobial resistance rates were comparable with different frequencies of resistance determinants in each country.

Elimination of Causative Antibody by Plasma Exchange in a Patient with an Acute Hemolytic Transfusion Reaction / 대한수혈학회지

An ABO-incompatible transfusion is a very rare event but it can cause severe adverse effects, including death. The prognosis is affected by various factors, such as the volume of infusion, underlying diseases, and immunologic state. Until now, however, there has been no consensus regarding the treatment of an ABO-incompatible transfusion except for conservative treatment. A 57 year-old male patient visited the authors' emergency unit with multiple trauma due to a car accident. He had a deep laceration on his left neck accompanied by severe bleeding. Because of his low blood pressure and low hemoglobin level due to bleeding, an emergency transfusion was attempted. Unfortunately, one unit of RBC was transfused incorrectly into the patient due to a clerical error during the identification of the patient. The patient was typed as O, RhD positive; the RBC administered was A, RhD positive. After the transfusion, the patient showed an acute hemolytic transfusion reaction due to gross hematuria. Plasma exchange was attempted and medical treatment with high dose steroid with diuretics was done simultaneously. Two cycles of plasma exchange were done and the patient appeared to recover from the acute adverse effects of the transfusion. The plasma exchange was stopped and medical treatments for the transfusion reactions were maintained for ten days. The patient recovered fully and was discharged after one month. Based on this case, although more studies are necessary for approval as a standard therapy, this case suggests that immediate plasma exchange with medical treatment can be very helpful for eliminating the isoagglutinins in ABO-incompatible transfusions.

Fungal Keratitis Caused by Corynespora cassiicola, a Plant Pathogen / 대한의진균학회지

A 74-year-old man presented with pain and progressively worsening vision from 20 days ago in the left eye. His ophthalmological history was significant for cataract extraction, scleromalacia, and three surgeries for pterygium removal in the left eye. Slit-lamp examination was remarkable for a 4.5×4.0 mm sized epithelial defect, with corneal stromal infiltration and melting and a surrounding feathery margin. Corneal scraping was performed, and culture of specimen demonstrated mold that grew on Sabouraud dextrose agar. The isolate was finally identified as Corynespora cassiicola based on DNA sequencing analysis of internal transcribed spacer (ITS) with maximum identity of 100%. The patient was treated successfully with intracameral amphotericin B injection and topical voriconazole and amphotericin B. To the best of our knowledge, this is the first reported case of mycotic keratitis caused by a plant pathogen, Corynespora cassiicola, in Korea.

Concurrence of e1a2 and e19a2 BCR-ABL1 Fusion Transcripts in a Typical Case of Chronic Myeloid Leukemia

No abstract available.

Isolation and Genetic Characterization of Orientia tsutsugamushi from Scrub Typhus Patients in Gyeongsangnam-do, Korea

Orientia tsutsugamushi (O. tsutsugamushi), which is endemic to an Asia-Pacific region, has increased its incidence and caused annually around 10 thousand patients infected with scrub typhus in Korea in the past several years. In the present study, we isolated 44 O. tsutsugamushi from the patients with febrile illness accompanied with or without an eschar in Gyeongsangnam-do, Korea. These isolates were characterized by genetic analysis of the major outer membrane protein, the 56-kDa type-specific antigen (tsa56), which is unique to O. tsutsugamushi. Two types of sequences of tsa56, designated by JJ1 and JJ2, were determined from 37 and 7 isolates of the 44 isolates, respectively. JJ1 and JJ2 showed 74.7~90.8% identity in nucleotide sequence and 66.1~90.5% identity in amino acid sequence with 33 reference strains except for Boryong and Kuroki. JJ1 and JJ2 had 100 and 99.9% nucleotide identity to Boryong strain, and 99.9 and 99.8% to Kuroki, which has been known to be similar to Boryong, respectively. In addition, they showed 77.9~ 81.4% nucleotide identity with the cluster of Gilliam-related genotypes, whereas they showed higher nucleotide identity (89.6~90.8%) with the cluster of Karp-related genotypes. To our knowledge, this is the first report to isolate O. tsutsugamushi and characterize their genotype as the Boryong in Jinju and West Gyeongsangnam-do, Korea, even though it has been reported that the Boryong was the predominant genotype in isolates from chiggers, domestic rodents, and patients in the southern part of Korea. Furthermore, our isolates could be useful source to study on the pathophysiology and epidemiology of scrub typhus in Korea.

A Case of Septic Shock Following Catheter-related Infection Caused by Lactococcus lactis subsp. lactis in an Adult

Lactococcus lactis is a gram-positive cocci used extensively in the dairy industry, but considered an unusual pathogen in humans. Among its five subspecies, L. lactis subsp. lactis in particular has rarely been reported as a pathogen. We report a case of septic shock caused by L. lactis subsp. lactis in an adult patient. A 64-yr-old male patient was admitted to outpatient clinics, with chief complaints of fever and chills for one week after convalescent hospital admission. He had severe ileus requiring surgery. He had a peripherally inserted central catheter from convalescent hospital, which was immediately removed. From two sets of blood and catheter tip cultures, we identified L. lactis subsp. lactis using the Vitek 2 system (bioMerieux Inc., USA), and confirmed this result by 16S rRNA sequencing. The patient was empirically treated with ciprofloxacin, and he recovered and was discharged.

Sepsis Due to Rhodotorula mucilaginosa in a Patient with Advanced Non-Small Cell Lung Cancer

Rhodotorula species are round to oval-shaped, multilateral budding, encapsulated yeasts that produce urease and do not ferment carbohydrates. Rhodotorula species form characteristic salmon-pink colored colonies owing to carotenoid pigment production. These yeasts form a part of the normal flora of moist skin and are found in the environment. Rhodotorula was traditionally considered a contaminant but is now progressively recognized as a human pathogen, especially in immunocompromised patients with central venous catheters. However, isolation of Rhodotorula species from blood has been very rarely reported in Korea. We report a case of sepsis due to Rhodotorula mucilaginosa infection in a patient who had received chemotherapy and supportive care for non-small cell lung cancer.

Molecular Identification and Amphotericin B Susceptibility Testing of Clinical Isolates of Aspergillus From 11 Hospitals in Korea

BACKGROUND: We investigated the species distribution and amphotericin B (AMB) susceptibility of Korean clinical Aspergillus isolates by using two Etests and the CLSI broth microdilution method. METHODS: A total of 136 Aspergillus isolates obtained from 11 university hospitals were identified by sequencing the internal transcribed spacer (ITS) and beta-tubulin genomic regions. Minimal inhibitory concentrations (MICs) of AMB were determined in Etests using Mueller-Hinton agar (Etest-MH) and RPMI agar (Etest-RPG), and categorical agreement with the CLSI method was assessed by using epidemiological cutoff values. RESULTS: ITS sequencing identified the following six Aspergillus species complexes: Aspergillus fumigatus (42.6% of the isolates), A. niger (23.5%), A. flavus (17.6%), A. terreus (11.0%), A. versicolor (4.4%), and A. ustus (0.7%). Cryptic species identifiable by beta-tubulin sequencing accounted for 25.7% (35/136) of the isolates. Of all 136 isolates, 36 (26.5%) had AMB MICs of > or =2 microg/mL by the CLSI method. The categorical agreement of Etest-RPG with the CLSI method was 98% for the A. fumigatus, A. niger, and A. versicolor complexes, 87% for the A. terreus complex, and 37.5% for the A. flavus complex. That of Etest-MH was < or =75% for the A. niger, A. flavus, A. terreus, and A. versicolor complexes but was higher for the A. fumigatus complex (98.3%). CONCLUSIONS: Aspergillus species other than A. fumigatus constitute about 60% of clinical Aspergillus isolates, and reduced AMB susceptibility is common among clinical isolates of Aspergillus in Korea. Molecular identification and AMB susceptibility testing by Etest-RPG may be useful for characterizing Aspergillus isolates of clinical relevance.

Comparison of the Vitek 2, API 20A, and 16s rRNA Gene Sequencing for the Identification of Anaerobic Bacteria / 대한임상미생물학회지

BACKGROUND: Recently, genotypic identification of anaerobes is emerging as an alternative to the phenotypic method. In this study, we evaluated the performance of Vitek 2, API 20A and 16s rRNA gene sequencing for the identification of anaerobic bacteria. METHODS: A total of 35 anaerobe reference strains were identified using Vitek 2, API 20A and 16s rRNA gene sequencing. We evaluated the performance of three methods on the basis of the accurate identification rates. RESULTS: The Vitek 2, API 20A and 16s rRNA gene sequencing identified 54.3, 15.4, and 94.3% of test strains correctly at the species level and identified 77.1, 42.3, and 100% at the genus level, respectively. Results of the McNemar's test showed that there was a significant difference between each of the three identification methods in species level identification (P value<0.05). CONCLUSION: 16s rRNA gene sequencing showed better performance than Vitek 2 or API 20A for anaerobic bacteria. Considering its excellent performance, 16s rRNA gene sequencing may be useful for accurate identification of anaerobic bacteria that cannot be correctly identified by phenotypic methods.

Recent Trends in Antimicrobial Resistance in Intensive Care Units in Korea / 병원감염관리

BACKGROUND: In general, higher resistance rates are observed among intensive care unit (ICU) isolates than non-ICU isolates. In this study, resistance rates of isolates from ICUs and non-ICUs were compared using the data generated from 20 hospitals in Korea. METHODS: Susceptibility data were collected from 20 hospitals participating in the Korean Nationwide Surveillance of Antimicrobial Resistance (KONSAR) program. Duplicate isolates were excluded from the analysis. The resistance rates did not include intermediate susceptibility. RESULTS: The most prevalent bacteria in the ICUs were Staphylococcus aureus (21%) and Acinetobacter spp. (19%), and those in non-ICU were Escherichia coli (27%) and S. aureus (14%). The resistance rates were higher in ICUs than in non-ICUs at 84% and 58% for methicillin-resistant S. aureus, 86% and 70% for methicillin-resistant coagulase-negative Staphylcoccus (CNS), 34% and 19% for vancomycin-resistant Enterococcus faecium, 38% and 19% for cefotaxime-resistant E. coli, 45% and 25% for cefotaxime-resistant Klebsiella pneumoniae, 42% and 24% for ceftazidime-resistant Enterobacter cloacae, 29% and 11% for ceftazidime-resistant Serattia marcescens, 83% and 44% for imipenem-resistant Acinetobacter spp., and 32% and 17% for imipenem-resistant Pseudomonas aeruginosa, respectively. CONCLUSION: The most prevalent bacteria in ICUs were S. aureus, CNS, and Acinetobacter spp., and high multi-drug resistance rates were observed in the Acinetobacter isolates. Therefore, infection control should be practiced in ICUs to prevent infections caused by multi-drug resistant bacteria.

Eggerthella lenta Bacteremia after Endoscopic Retrograde Cholangiopancreatography in an End-Stage Renal Disease Patient / 대한임상미생물학회지

Eggerthella lenta is rarely isolated from blood but may occur as an opportunistic pathogen with high morbidity and mortality. We report a case of E. lenta bacteremia after an endoscopic retrograde cholangiopancreatography in an end-stage renal disease patient.

Relationship between Serum Gamma-glutamyltransferase Levels within Reference Intervals and the Prevalence of Metabolic Syndrome and Diabetes Mellitus in Adults

BACKGROUND: This study was conducted to establish reference intervals (RIs) for serum gamma-glutamyltransferase (GGT), and to evaluate the association between serum GGT levels within RIs and the prevalence of metabolic syndrome (MetS) and type 2 diabetes mellitus (DM) in men and women. METHODS: A total of 363 healthy adults (137 men and 226 women) were enrolled for establishing the RIs of serum GGT. A cross-sectional study was conducted with 919 individuals (519 men and 400 women) to evaluate the associations between gender-specific serum GGT RI quartiles and prevalence of MetS and DM. RESULTS: The RIs for serum GGT levels (central 95th percentile ranges) were 9.0-70.6 IU/L and 4.0-31.3 IU/L in men and women, respectively. In men, the odds ratios (ORs) and 95% confidence intervals (CIs) for the prevalence of MetS in 4 serum GGT quartiles (lowest to highest) were 1.0 (reference), 3.6 (0.7-18.0), 8.8 (2.0-39.1), and 17.4 (4.0-75.3), respectively, while the ORs (95% CIs) for the prevalence of DM were 1.0 (reference), 1.0 (0.3-3.0), 1.7 (0.6-4.6), and 2.6 (1.0-6.6), respectively. In women, the corresponding ORs (95% CIs) were 1.0 (reference), 3.3 (0.6-16.6), 5.8 (1.2-27.3), and 18.8 (4.3-82.2) for MetS, respectively, and 1.0 (reference), 1.6 (0.3-9.7), 1.6 (0.3-9.9), and 8.0 (1.7-36.7) for DM, respectively. These significant relationships persisted after adjusting for age, alcohol intake, body mass index, and smoking. CONCLUSIONS: Serum GGT levels, even within RIs, were proportionally associated with prevalence of metabolic syndrome and DM in both men and women. Serum GGT level may be an independent predictor for chronic degenerative diseases.

Nasal Colonization and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus among Hemodialysis Patients in 7 Korean Hospitals / 병원감염관리

BACKGROUND: Staphylococcus aureus is a major bacteremia-causing pathogen in hemodialysis patients, frequently colonizing patient skin and mucosa. Active infection control is necessary to prevent methicillin-resistant S. aureus (MRSA) infection in hospitals; however, the spread of community-associated MRSA has recently become a concern for MRSA infection control. We evaluated the nasal colonization of MRSA among hemodialysis patients and the molecular characterization of the MRSA isolates. METHODS: Nasal swabs were obtained from 482 hemodialysis patients in 7 nationwide hospitals in November 2009, and cultured for MRSA colonization. Swabs were inoculated and cultured in 6.5% NaCl tryptic soy broth, then subcultured on MRSASelect medium (Bio-Rad, Hercules, CA) for 20-24 h. Multiplex PCR was performed to analyze staphylococcal cassette chromosome mec (SCCmec) types of MRSA isolates. RESULTS: Of 482 hemodialysis patients, 57 (11.8%) carried MRSA, ranging from 6.7% to 19.0%. Among the 57 MRSA isolates, we identified 3 (5.3%) SCCmec II, 1 (1.8%) SCCmec IIA, 30 (52.6%) SCCmec IIB, 1 (1.8%) SCCmec III, 6 (10.5%) SCCmec IV, and 16 (28.1%) SCCmec IVA subtypes. CONCLUSION: The MRSA carriage rate (11.8%) of hemodialysis patients in this study was high. The SCCmec IIB subtype, a healthcare-associated strain, was the predominant strain, although SCCmec IV isolates, typically found in community-associated MRSA infections, were also frequently observed. To prevent healthcare-associated MRSA infections in hemodialysis patients, standardized infection control measures should be performed, and efforts to reduce MRSA carriage rates should be considered.

Distribution of Yeast and Mold Species Isolated from Clinical Specimens at 12 Hospitals in Korea during 2011 / 대한임상미생물학회지

BACKGROUND: The incidence of fungal infections varies among hospitals and between different time periods. We performed a nationwide survey in Korea to investigate the distribution of yeast and mold species recovered from clinical specimens. METHODS: The distributions of clinical isolates of yeast and mold species obtained from 12 university hospitals between January and December 2011 were evaluated relative to the hospital and specimen type. RESULTS: A total of 39,533 fungal isolates (37,847 yeast and 1,686 mold isolates) were obtained. C. albicans was the predominant species (49.4%) among the yeast isolates from all clinical specimens, followed by C. glabrata (7.2%) and C. tropicalis (6.5%). For 5,248 yeast isolates from sterile body fluids, blood was the most common source of yeasts (71.1%), followed by peritoneal fluid (9.4%). Although C. albicans was the predominant species at all but two hospitals, the rate of non-albicans Candida species varied from 71.2% to 40.1%, depending on the hospital. The yeast species recovered most frequently from the sterile body fluids was C. albicans (41.7%), followed by C. parapsilosis (17.8%) and C. glabrata (14.4%), while that from non-sterile sites was C. albicans (50.7%), followed by C. glabrata (6.0%) and C. tropicalis (5.5%). For mold-forming fungi, Aspergillus species (62.3%) were most common, followed by Trichophyton species (15.4%). Respiratory specimens were the most common source of molds (39.6%), followed by abscesses/wounds (28.4%) and tissues (17.5%). CONCLUSION: The rank order of distribution for different fungal species varied among hospitals and specimen types. Continual national surveillance programs are essential for identifying possible changes in fungal infection patterns.