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Background@#There is a global increase in isolation of nontuberculous mycobacteria (NTM). The aim of the study was to analyze longitudinal trends of NTM identification and pattern of antimicrobial susceptibility testing. @*Methods@#NTM recovery rates, distribution of NTM species identification, and antimicrobial susceptibility pattern of NTM at Pusan National University Yangsan Hospital between January 2016 and December 2020 were retrospectively analyzed. @*Results@#A total of 52,456 specimens from 21,264 patients were submitted for mycobacterial culture, of which 2,521 from 1,410 patients were NTM positive over five years (January 2016 to December 2020). NTM isolation showed an increasing trend from 2016 to 2020 (p<0.001, test for trend) mainly caused by Mycobacterium avium complex. The vast majority of M. avium complex were susceptible to key agents clarithromycin and amikacin. For Mycobacterium kansasii, resistance to rifampin and clarithromycin is rare. Amikacin was the most effective drug against Mycobacterium abscessus subspecies abscessus and Mycobacterium subspecies massiliense. Most of M. subspecies massiliense were susceptible to clarithromycin, while the majority of M. abscessus subspecies abscessus were resistant to clarithromycin (p<0.001). @*Conclusion@#There was an increasing trend of NTM isolation in our hospital. Resistance to key drugs was uncommon for most NTM species except for M. abscessus subspecies abscessus against clarithromycin.
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Adverse transfusion reactions (ATRs) are unexpected reactions to transfusion. This study examined the frequency, types of ATRs, and related blood products retrospectively in pediatric patients with less information than in adult patients. Four hundred and forty transfusions were performed for two months at a children’s hospital: 247 units of red blood cell (RBC) products, 142 units of platelet products, and 41 units of fresh frozen plasma (FFP) were used.Five adverse reactions occurred in five patients, three cases were allergic reactions, and two were febrile nonhemolytic reactions. The frequency was 1.13%, and apheresis platelets and leukocyte-reduced RBC were transfused. Two patients’ ATRs were found in the previous transfusions, and ATRs were repeated in subsequent transfusions in one patient. One of the ATRs was not reported to the blood bank and was then discovered during the study. Because pediatric patients may have limitations in recognizing or expressing their symptoms compared to adults, medical staff rely solely on vital signs and laboratory results rather than symptoms, causing difficulty in noticing ATRs. Information on ATRs and education on appropriate blood products will improve awareness of ATRs and blood management among medical staff at transfusion sites and blood banks.
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Background@#Multidrug-resistant Acinetobacter baumannii (MDRAB) is widespread among intensive care units worldwide, posing a threat to patients and the health system. We describe the successful management of a MDRAB outbreak by implementing an infection-control strategy in a pediatric intensive care unit (PICU). @*Methods@#This retrospective study investigated the patients admitted to the PICU in periods 1 (8 months) and 2 (7 months), from the index MDRAB case to intervention implementation, and from intervention implementation to cessation of MDRAB spread. An infection-control strategy was designed following six concepts: 1) cohort isolation of colonized patients, 2) enforcement of hand hygiene, 3) universal contact precautions, 4) environmental management, 5) periodic surveillance culture study, and 6) monitoring and feedback. @*Results@#Of the 427 patients, 29 were confirmed to have MDRAB colonization, of which 18 had MDRAB infections. Overall incidence per 1,000 patient days decreased from 7.8 (period 1) to 5.8 (period 2). The MDRAB outbreak was declared terminated after the 6-month followup following period 2. MDRAB was detected on the computer keyboard and in condensed water inside the ventilator circuits. The rate of hand hygiene performance was the lowest in the three months before and after index case admission and increased from 84% (period 1) to 95% (period 2). Patients with higher severity, indicated by a higher Pediatric Risk of Mortality III score, were more likely to develop colonization (P = 0.030), because they had invasive devices and required more contact with healthcare workers. MDRAB colonization contributed to an increase in the duration of mechanical ventilation and PICU stay (P < 0.001), but did not affect mortality (P = 0.273). @*Conclusion@#The MDRAB outbreak was successfully terminated by the implementation of a comprehensive infection-control strategy focused on the promotion of hand hygiene, universal contact precautions, and environmental management through multidisciplinary teamwork.
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Culture tests are very important in choosing the appropriate antibiotics for bacterial infections. In some cases, bacteria that could not be identified in standard culture bottles could be detected using blood culture bottles. A previously healthy 13-year-old boy visited our emergency room. He experienced pain, redness, and hardness of periumbilical skin and a fever for five days. There was no history of abdominal surgery and penetrating trauma.Computed tomography showed abscess with cellulitis at the periumbilical soft tissue with no congenital anomaly. Ultrasonography-guided aspiration was performed, and about 8.5 mL of the purulent abscess was aspirated. The abscess was cultured using blood culture bottle. The pus grew Actinomyces radingae and Clostridium ramosum. When performing the pus culture, using blood culture bottles can be more effective and rapid than the standard culture method for the detection of bacterial pathogens.
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Background@#In Korea, there were issues regarding the use of immunoassays for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies to detect infection. So, we compared antibody results of eight kinds of commercial immunoassays using clinical remnant specimens. @*Methods@#We compared the results of several immunoassay kits tested on 40 serum samples from 15 confirmed patients and 86 remnant serum samples from clinical laboratory.Eight kinds of IVD kits—four enzyme-linked immunosorbent assay, two lateral flow rapid immunochromatographic assays, and two chemiluminescent immunoassays with one RUO kit were tested. @*Results@#Among 40 serum samples from 15 coronavirus disease 2019 (COVID-19) patients, 35 yielded at least one positive result for detecting antibodies in the combined assessment. There were inconsistent results in 12 (28%) samples by single immunoassay. Forty samples collected in 2019 before the first COVID-19 Korean case showed negative results except for one equivocal result. @*Conclusion@#The discrepant results obtained with different immunoassay kits in this study show that serological assessment of SARS-CoV-2 by a single immunoassay requires caution not only in detecting infection but also in assessing immunologic status.
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Background@#In Korea, there were issues regarding the use of immunoassays for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies to detect infection. So, we compared antibody results of eight kinds of commercial immunoassays using clinical remnant specimens. @*Methods@#We compared the results of several immunoassay kits tested on 40 serum samples from 15 confirmed patients and 86 remnant serum samples from clinical laboratory.Eight kinds of IVD kits—four enzyme-linked immunosorbent assay, two lateral flow rapid immunochromatographic assays, and two chemiluminescent immunoassays with one RUO kit were tested. @*Results@#Among 40 serum samples from 15 coronavirus disease 2019 (COVID-19) patients, 35 yielded at least one positive result for detecting antibodies in the combined assessment. There were inconsistent results in 12 (28%) samples by single immunoassay. Forty samples collected in 2019 before the first COVID-19 Korean case showed negative results except for one equivocal result. @*Conclusion@#The discrepant results obtained with different immunoassay kits in this study show that serological assessment of SARS-CoV-2 by a single immunoassay requires caution not only in detecting infection but also in assessing immunologic status.
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Culture tests are very important in choosing the appropriate antibiotics for bacterial infections. In some cases, bacteria that could not be identified in standard culture bottles could be detected using blood culture bottles. A previously healthy 13-year-old boy visited our emergency room. He experienced pain, redness, and hardness of periumbilical skin and a fever for five days. There was no history of abdominal surgery and penetrating trauma.Computed tomography showed abscess with cellulitis at the periumbilical soft tissue with no congenital anomaly. Ultrasonography-guided aspiration was performed, and about 8.5 mL of the purulent abscess was aspirated. The abscess was cultured using blood culture bottle. The pus grew Actinomyces radingae and Clostridium ramosum. When performing the pus culture, using blood culture bottles can be more effective and rapid than the standard culture method for the detection of bacterial pathogens.
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BACKGROUND: Although the incidence of tuberculosis (TB) is decreasing, cases of multidrug-resistant (MDR) TB and extensively drug-resistant (XDR) TB continue to increase. As conventional phenotype drug susceptibility testing (pDST) takes six to eight weeks, molecular assays are widely used to determine drug resistance. we developed QuantaMatrix Multiplexed Assay Platform (QMAP) MDR/XDR assay (QuantaMatrix Inc., Seoul, Korea) that can simultaneously detect mutations related to both first- and second-line drug resistance (rifampin, isoniazid, ethambutol, fluoroquinolones, second-line injectable drugs, and streptomycin). METHODS: We used 190 clinical Mycobacterium tuberculosis (MTB) strains isolated from Myanmar, compared QMAP and pDST results, and determined concordance rates. Additionally, we performed sequence analyses for discordant results. RESULTS: QMAP results were 87.9% (167/190) concordant with pDST results. In the 23 isolates with discordant results, the QMAP and DNA sequencing results completely matched. CONCLUSIONS: The QMAP MDR/XDR assay can detect all known DNA mutations associated with drug resistance for both MDR- and XDR-MTB strains. It can be used for molecular diagnosis of MDR- and XDR-TB to rapidly initiate appropriate anti-TB drug therapy.
Subject(s)
Diagnosis , DNA , Drug Resistance , Drug Therapy , Ethambutol , Extensively Drug-Resistant Tuberculosis , Fluoroquinolones , Incidence , Isoniazid , Myanmar , Mycobacterium tuberculosis , Phenotype , Seoul , Sequence Analysis , Sequence Analysis, DNA , Tuberculosis , Tuberculosis, Multidrug-ResistantABSTRACT
The Coronavirus Disease 19 (COVID-19), which emerged as pneumonia from an unknown agent for the first time at the end of 2019, has dramatically transformed our world into one that is highly unrecognizable today. Newly emerging infectious diseases have been occurring more frequently than ever. Opportunities of such deadly microorganisms to adapt to humans—as well as spread between people on a massive scale—are growing because of active human mobility. We have translated and published the book, “One Health: People, Animals, and the Environment.” The original book, published in 2014 by ASM Press, shows the concept and applications of One Health. The current book comprises five parts: definition and importance of One Health, zoonotic and environmental drivers of emerging infectious diseases, One Health and antibiotic resistance, disease surveillance, and realizing the One Health Initiative’s objectives. This translation and publication was the first science book publishing project performed under the name of the Korean Society of Clinical Microbiology. We are actively working toward providing academic information and advancing our identity in other scientific fields as well as to the public.
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BACKGROUND: Genetic variants and haplotypes of the interleukin-10 (IL10) gene have been shown to affect clinical outcomes, including the incidence of opportunistic infections (OIs), in HIV-infected patients. This study investigated the effect of IL10 gene variants on susceptibility to OIs in HIV-infected Korean patients in the era of highly active antiretroviral therapy (HAART). METHODS: Eighty-five HIV-infected patients receiving HAART were enrolled in the study. OIs were diagnosed based on the published criteria of the Korean Society for AIDS. Three promoter SNPs and four haplotype-tagging SNPs (htSNPs) of IL10 were selected and genotyped. The haplotypes were reconstructed according to the genotyping data and linkage disequilibrium (LD) status of these SNPs. RESULTS: During the study, 38 OIs developed in 23 of the 85 patients (27.1%), at a rate of 1.7 episodes/patient. Carrying the minor alleles at the rs1518111, rs3024490, and rs1800871 SNPs had a protective effect against OIs (adjusted P=0.035). Among the seven assessed variants, only three possible haplotypes were observed. The second most common haplotype, which was composed of the rs1518111 minor allele and the rs3021094 major allele showed a protective effect against OIs (P=0.0153). CONCLUSION: This study demonstrated that some IL10 genetic variants and haplotypes are associated with protective effects against OIs in the era of HAART. These data suggest the potential of two htSNPs, rs1518111 and rs3021094, as markers revealing the genetic association of IL10 in Koreans. This is the first report on the association of IL10 with OIs in HIV-infected Korean patients in the era of HAART.
Subject(s)
Humans , Alleles , Antiretroviral Therapy, Highly Active , Haplotypes , HIV , Incidence , Interleukin-10 , Korea , Linkage Disequilibrium , Opportunistic Infections , Polymorphism, Single NucleotideABSTRACT
Infective endocarditis caused by Abiotrophia defectiva is rarely encountered. A 67-year-old male transferred from a local hospital presented with severe dyspnea and pulmonary edema. Preoperative transthoracic echocardiography revealed severe mitral regurgitation with large vegetation. Blood cultures grew A. defectiva, a gram positive, nutritionally deficient streptococcus variant. Emergent mitral valve replacement through right thoracotomy was performed, and after completing six weeks of antibiotic combination therapy (vancomycin, ampicillin, and gentamicin), the patient recovered fully. Because of the need for prompt surgical treatment and long-term antibiotic therapy and lack of laboratory experience with the organism, physicians and laboratory workers should pay close attention to the possibility of A. defectiva infective endocarditis when gram positive cocci are detected in blood cultures.
Subject(s)
Adult , Aged , Humans , Male , Abiotrophia , Ampicillin , Dyspnea , Echocardiography , Endocarditis , Endocarditis, Bacterial , Gram-Positive Cocci , Mitral Valve , Mitral Valve Insufficiency , Pulmonary Edema , Streptococcus , ThoracotomyABSTRACT
BACKGROUND: Several factors contribute to differences in Streptococcus pneumoniae serotype distribution. We investigated the serotype distribution and antimicrobial resistance of S. pneumoniae isolated between 2014 and 2016 in Korea. METHODS: We collected a total of 1,855 S. pneumoniae isolates from 44 hospitals between May 2014 and May 2016, and analyzed the serotypes by sequential multiplex PCR. We investigated the distribution of each serotype by patient age, source of the clinical specimen, and antimicrobial resistance pattern. RESULTS: The most common serotypes were 11A (10.1%), followed by 19A (8.8%), 3 (8.5%), 34 (8.1%), 23A (7.3%), and 35B (6.2%). The major invasive serotypes were 3 (12.6%), 19A (7.8%), 34 (7.8%), 10A (6.8%), and 11A (6.8%). Serotypes 10A, 15B, 19A, and 12F were more common in patients ≤5 years old, while serotype 3 was more common in patients ≥65 years old compared with the other age groups. The coverage rates of pneumococcal conjugate vaccine (PCV)7, PCV10, PCV13, and pneumococcal polysaccharide vaccine 23 were 11.8%, 12.12%, 33.3%, and 53.6%, respectively. Of the 1,855 isolates, 857 (46.2%) were multi-drug resistant (MDR), with serotypes 11A and 19A predominant among the MDR strains. The resistance rates against penicillin, cefotaxime, and levofloxacin were 22.8%, 12.5%, and 9.4%, respectively. CONCLUSIONS: There were significant changes in the major S. pneumoniae serotypes in the community. Non-PCV13 serotypes increased in patients ≤5 years old following the introduction of national immunization programs with the 10- and 13-polyvalent vaccines.
Subject(s)
Humans , Cefotaxime , Immunization Programs , Korea , Levofloxacin , Multiplex Polymerase Chain Reaction , Penicillins , Pneumococcal Vaccines , Pneumonia , Serogroup , Streptococcus pneumoniae , Streptococcus , VaccinesABSTRACT
BACKGROUND@#Blood transfusion poses high risks and has a high probability of error because of the complexity and involvement of several people in the process. The purpose of this study was to share our experience in classifying reports related to blood transfusions. We included patient safety reports that were prepared over a 10-year period that began from the opening of the hospital. We then analyzed the causes and the corrective actions.@*METHODS@#We analyzed 125 reports related to blood transfusions, and these reports were included in the patient safety reports received from November 2008 to December 2018. The events were categorized as sampling error, inspection error, testing error, issue error, disposal error, transfusing blood components error, or others error, depending on the stage of the blood transfusion process. Regardless of the cause, the event that led to an inappropriate transfusion was classified as a transfusion incident.@*RESULTS@#The number of blood transfusions per year increased, and the rate of blood transfusion accidents ranged from 0.00% to 0.05% per year. A total of 125 reports were prepared over a 10-year period, and these included 8 blood sampling errors, 11 testing errors, 2 issuing errors, 94 disposal errors, 3 others errors, and 7 errors associated with the transfusing of blood components. After the transfusion incident, PDA was applied as a solution. Transfusing the wrong blood components did not occur, and the incidence of taking blood from the wrong patients was decreased.@*CONCLUSION@#We applied corrective actions according to the cause of the event and we confirmed that the blood transfusion incidents decreased.
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BACKGROUND: Massive hemorrhage due to trauma is one of the major causes of death in trauma patients, and the quick supply of appropriate blood products is critical in order to reduce the mortality rate. We introduced a massive transfusion protocol (MTP) for safe and rapid transfusion of trauma patients. Using records collected since its adoption, we compared the characteristics of MTP applied group (MTP group) and MTP not applied group (non-MTP group) to determine whether there is an indicator for predicting patients to be treated with MTP. METHODS: We retrospectively reviewed the electronic medical records and laboratory findings of patients who received massive transfusions in the trauma emergency room of a single tertiary hospital from February to August 2018. We analyzed various laboratory test results, the amount and ratio of the transfused blood products, and the time required for blood products to be released for the MTP group and the non-MTP group. RESULTS: Of the 54 trauma patients who received massive transfusions, 31 were in the MTP group and 22 in the non-MTP group. There was no significant difference in initial vital signs (except blood pressure) and laboratory test results. Also there was no difference in the amount and ratio of blood products, but the time required for blood product release was shorter in the MTP group. CONCLUSION: There was no significant difference in clinical findings such as initial vital signs and laboratory test results between the MTP and non-MTP groups, but required blood products were prepared and released more quickly for the MTP group.
Subject(s)
Humans , Cause of Death , Electronic Health Records , Emergency Service, Hospital , Hemorrhage , Mortality , Retrospective Studies , Tertiary Care Centers , Vital SignsABSTRACT
Laboratory medicine is a specialized division that supports physicians in the care of patients by providing rapid and accurate in vitro diagnostic tests. Standardization of every component of a specific test is essential for producing accurate results. The Clinical and Laboratory Standards Institute (CLSI) was founded to develop a formal consensus process for standardization in 1968, and has been publishing standards and guidelines covering all aspects of clinical, research, and other laboratory work. CLSI guidelines are widely used around the world for standardization. The CLSI antimicrobial susceptibility testing subcommittee (AST SC) consists of 6 standing and many ad hoc working groups. Members of the AST SC review submitted proposals and suggestions, decide on approving these submissions in face-to-face meetings held twice a year, and revise CLSI documents accordingly. As these face-to-face meetings are open to anyone who registers to attend, I strongly encourage the members of our Society to attend and actively participate in document development.
Subject(s)
Humans , Consensus , Diagnostic Tests, Routine , In Vitro TechniquesABSTRACT
BACKGROUND: Urine culture is one of the most frequently requested tests in microbiology. Automated urine analyzers yield much infection-related information. The Sysmex UF-5000 analyzer (Sysmex, Japan) is a new flow cytometry urine analyzer capable of quantifying urinary particles, including bacteria, WBCs, and yeast-like cells (YLCs) and can provide a Gram stainability flag. In this work, we evaluated how many unnecessary urine cultures could be screened out using the UF-5000. METHODS: We compared the culture results of 126 urine samples among 453 requested urine cultures (from sources other than the Urology and Nephrology departments) with urinalysis results. Urine cultures were considered positive if bacterial or YLC growth was ≥104 CFUs/mL. RESULTS: We used urinalysis cut-off values of 50/µL and 100/µL for bacteria and YLC, respectively. Forty eight of the 126 (38.1%, or 10.6% of 453 requested) cultures were below these cut-off values and did not contain any culture-positive samples. CONCLUSION: Bacteria and YLC counts generated using the UF-5000 analyzer could be used to screen out negative cultures and reduce urine culture volume by ~10% without sacrificing detection of positive cultures.
Subject(s)
Bacteria , Flow Cytometry , Nephrology , Urinalysis , Urinary Tract Infections , UrologyABSTRACT
The acknowledgement was missed without intention. The authors ask to add the acknowledgement ‘This work was supported by a 2-Year Research Grant of Pusan National University.’ in an appropriate section.
Subject(s)
Financing, Organized , Intention , Mycobacterium tuberculosis , Mycobacterium , RifampinABSTRACT
BACKGROUND: A simple and cost-effective method is needed for the detection of rifampicin resistance in Mycobacterium tuberculosis in resource-limited settings. We suggest a broth medium-based method using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC) for detection of rifampin resistance of tubercle bacilli within a reasonable time frame. METHODS: The type strain (M. tuberculosis H37Rv) and 45 cultured clinical strains of M. tuberculosis (35 rifampin-susceptible and 10 rifampin-resistant) were used. Phenotypes of rifampicin resistance were tested by the Korea Institute of Tuberculosis, and confirmed by GenoType MTBDRplus (Hain Lifescience, Germany). Susceptibility tests were performed using STC-containing OADC-enriched Middlebrook 7H9 broth (BD, USA). RESULTS: All tests were finished in 3 to 6 days. The same results were obtained with the standard and current methods for all 45 clinical isolates (100% sensitivity and specificity for resistance detection). CONCLUSION: The current method using STC is a good alternative for detecting M. tuberculosis rifampin resistance in a cost-effective and timely fashion, which is particularly important in resource-limited settings.
Subject(s)
Genotype , Korea , Methods , Mycobacterium tuberculosis , Mycobacterium , Phenotype , Rifampin , Sensitivity and Specificity , TuberculosisABSTRACT
BACKGROUND: There have been few evaluations of the performance of automatic stainers used instead of manual staining in clinical laboratories. We evaluated the performance of an automated stainer, KS-S100 (KS Co. Ltd., Korea), in Gram and acid-fast fluorescence staining of clinical specimens. METHODS: Repeatability was evaluated by comparing the results of Gram stains performed 10 times over 5 days using two standard strains and duplicated acid-fast bacilli (AFB) fluorescence stains using 40 samples. Comparisons to manual staining and to another automatic stainer, AT-2000 (Dagatron, Korea), were performed using 40 remnant respiratory specimens or liquid AFB culture media. The results were interpreted by two experienced technicians, and total test time was measured during the staining of 1, 10, and 20 slides. RESULTS: All 10 pairs of Gram staining results obtained with KS-S100 were identical, and the concordance rate of the duplicate AFB fluorescence stains was 92.5%. Among the results for 20 culture-positive liquid media samples, three AFB fluorescent staining results were not concordant. The weighted kappa values between KS-S100 and manual staining for Gram and AFB fluorescence staining were both 0.94, with concordance within the ±1-grade range. For the staining of a single slide, manual staining was faster. KS-S100 was more efficient than AT-2000 at staining 20 slides. CONCLUSIONS: The automated stainer KS-S100 showed reproducible results comparable to those of manual staining in two major microbiological staining methods, Gram and AFB fluorescence staining, used in clinical applications. Performance evaluations should be conducted before implementation of the automated stainer in microbiological staining.