ABSTRACT
Automated blood culture systems are widely used in clinical microbiology laboratories to minimize the workload of laboratory personnel and permit fast turnaround times. However, sometimes false positive signals occur due to leukocytosis, presence of fastidious bacteria, or unexplained causes. We experienced false positive signal in a patient with hyperleukocytosis for the first time since the automated blood culture system was introduced in our hospital over 20 years ago. We present two case reports with literature review and describe the procedure for dealing with false-positive cases in our hospital.
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Background@#Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. @*Methods@#S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. @*Results@#Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. @*Conclusions@#Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.
ABSTRACT
While the coronavirus disease 2019 pandemic is ongoing, monkeypox has been rapidly spreading in non-endemic countries since May 2022. Accurate and rapid laboratory tests are essential for identifying and controlling monkeypox. Korean Society for Laboratory Medicine and the Korea Disease Prevention and Control Agency have proposed guidelines for diagnosing monkeypox in clinical laboratories in Korea. These guidelines cover the type of tests, selection of specimens, collection of specimens, diagnostic methods, interpretation of test results, and biosafety. Molecular tests are recommended as confirmatory tests. Skin lesion specimens are recommended for testing in the symptomatic stage, and the collection of both blood and oropharyngeal swabs is recommended in the presymptomatic or prodromal stage.
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Plasma exchange performed with the aid of acid-citrate-dextrose formula A (ACD-A) is generally regarded as safe. However, unfractionated heparin (UFH) can serve as an anticoagulant for patients experiencing serious side effects such as anaphylaxis. No guidelines have currently been defined for the stand-alone UFH dosing during plasma exchange. We describe here two patients who developed anaphylaxis to ACD-A during plasma exchange, and we successfully used UFH as a standalone anticoagulant. The first patient was a 55-year-old man who required plasma exchange before ABO-incompatible kidney transplantation. During plasma exchange, he developed an allergic reaction. Thereafter, UFH was used as a standalone anticoagulant during four sessions of plasma exchange; the UFH (5,000 units) was added to a 500 mL normal saline bag and the UFH:whole blood ratio was maintained at 1:28. The second patient was an 80-year-old woman with steroid pulse-resistant neuromyelitis optica. She developed an allergic reaction during the first session of plasma exchange. The patient subsequently underwent five successful sessions of plasma exchange using UFH as a standalone anticoagulant. These findings may be useful when establishing a protocol for UFH as a standalone anticoagulant during plasma exchange in patients who develop an allergic reaction to citrate.
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Background@#Detection of anti-human leukocyte antigen (HLA) antibodies is important during the selection of an appropriate donor prior to organ transplantation and also for monitoring the patients after transplantation. In this study, we compared antibodies detected via C3d assays, which monitors C3d complement-binding activities of HLA antibodies with those detected via single antigen bead (SAB) assays. @*Methods@#A total of 66 serum samples were tested in parallel by SAB assays (Immucor Transplant Diagnostics, USA) and C3d assays (Immucor) for the detection of HLA class II antibodies. The relationship between these two methods was analyzed based on the types, numbers, median fluorescent intensity (MFI) values, and positivity of the antibodies using MATCH IT! Antibody (Immucor) program. @*Results@#The number of antibodies obtained based on SAB and C3d assays was the highest with 24 samples (36.4%) in the 11–20 range and 23 (34.8%) in the 2–5 range detected via each assay. Among the SAB-positive antibodies, only 28 (6.4%) of the 440 antibodies with MFI ≤3,000 were C3d-positive, and 341 (61.3%) of the 556 antibodies with MFI ≥3,001 were C3d-positive. Whereas, among the 442 C3d-positive antibodies, SAB assays were positive except for 32 (7.2%) and 41 (9.3%) antibodies in the sections of MFI ≤500 and 1,001 ≤MFI ≤10,000, respectively. C3d-positive samples had higher maximum MFI values based on SAB assays, compared with C3d-negative samples. @*Conclusions@#MFI values of HLA class II antibodies detected through SAB assays in C3d-positive samples were higher than those in C3d-negative samples.
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The first case of coronavirus disease 2019 (COVID-19) in Korea was reported in January 2020.As the secondary transmissions accelerated within the country, the government revised the outbreak alert for COVID-19 from attention to caution. Mid-February, when a massive outbreak was reported from a church in Daegu, our institution initiated testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 300 laboratory tests were performed within the first 2 months, before the number of cases began to decline. Here, we describe our experience of 4 months at the department of Laboratory Medicine, Keimyung University Dongsan Hospital, located in Daegu, where a massive COVID-19 outbreak occurred.
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The outbreak of coronavirus disease 2019 (COVID-19), which began in December 2019, is still ongoing in Korea, with >9,000 confirmed cases as of March 25, 2020. COVID-19 is a severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) infection, and real-time reverse transcription-PCR is currently the most reliable diagnostic method for COVID-19 around the world. Korean Society for Laboratory Medicine and the Korea Centers for Disease Prevention and Control propose guidelines for diagnosing COVID-19 in clinical laboratories in Korea. These guidelines are based on other related domestic and international guidelines, as well as expert opinions and include the selection of test subjects, selection of specimens, diagnostic methods, interpretation of test results, and biosafety.
ABSTRACT
The first case of coronavirus disease 2019 (COVID-19) in Korea was reported in January 2020.As the secondary transmissions accelerated within the country, the government revised the outbreak alert for COVID-19 from attention to caution. Mid-February, when a massive outbreak was reported from a church in Daegu, our institution initiated testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 300 laboratory tests were performed within the first 2 months, before the number of cases began to decline. Here, we describe our experience of 4 months at the department of Laboratory Medicine, Keimyung University Dongsan Hospital, located in Daegu, where a massive COVID-19 outbreak occurred.
ABSTRACT
Background@#Detection of anti-human leukocyte antigen (HLA) antibodies is important during the selection of an appropriate donor prior to organ transplantation and also for monitoring the patients after transplantation. In this study, we compared antibodies detected via C3d assays, which monitors C3d complement-binding activities of HLA antibodies with those detected via single antigen bead (SAB) assays. @*Methods@#A total of 66 serum samples were tested in parallel by SAB assays (Immucor Transplant Diagnostics, USA) and C3d assays (Immucor) for the detection of HLA class II antibodies. The relationship between these two methods was analyzed based on the types, numbers, median fluorescent intensity (MFI) values, and positivity of the antibodies using MATCH IT! Antibody (Immucor) program. @*Results@#The number of antibodies obtained based on SAB and C3d assays was the highest with 24 samples (36.4%) in the 11–20 range and 23 (34.8%) in the 2–5 range detected via each assay. Among the SAB-positive antibodies, only 28 (6.4%) of the 440 antibodies with MFI ≤3,000 were C3d-positive, and 341 (61.3%) of the 556 antibodies with MFI ≥3,001 were C3d-positive. Whereas, among the 442 C3d-positive antibodies, SAB assays were positive except for 32 (7.2%) and 41 (9.3%) antibodies in the sections of MFI ≤500 and 1,001 ≤MFI ≤10,000, respectively. C3d-positive samples had higher maximum MFI values based on SAB assays, compared with C3d-negative samples. @*Conclusions@#MFI values of HLA class II antibodies detected through SAB assays in C3d-positive samples were higher than those in C3d-negative samples.
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From October 2015 to August 2018, tapeworm proglottids were obtained from 10 patients who were residents of Daegu and Gyeongbuk provinces and had a history of raw beef consumption. Most of them had no overseas travel experience. The gravid proglottids obtained from the 10 cases had 15–20 lateral uterine branches. A part of internal transcribed spacer 1 (ITS1) DNA of the 10 cases, amplified by polymerase chain reaction (PCR) and digested with AleI restriction enzyme, produced the same band pattern of Taenia saginata, which differentiated from T. asiatica and T. solium. Sequences of ITS1 and cytochrome c oxidase subunit 1 (cox1) showed higher homology to T. saginata than to T. asiatica and T. solium. Collectively, these 10 cases were identified as T. saginata human infections. As taeniasis is one of the important parasitic diseases in humans, it is necessary to maintain hygienic conditions during livestock farming to avoid public health concerns.
Subject(s)
Humans , Agriculture , Cestoda , DNA , DNA, Ribosomal , Electron Transport Complex IV , Livestock , Parasitic Diseases , Polymerase Chain Reaction , Public Health , Red Meat , Republic of Korea , Taenia saginata , Taenia , TaeniasisABSTRACT
Staphylococcus pettenkoferi is a coagulase-negative staphylococci (CoNS) of growing concern. As CoNS could be an important cause of infections in hospitalized patients, especially in immunocompromised patients, accurate identification is critical to timely and effective treatment. In the past, S. pettenkoferi was not identifed by conventional methods or was misidentified as another Staphylococcus species or another genus. To the best of our knowledge, this is the first case of S. pettenkoferi identified using Vitek MS (bioMérieux, France). Two patients admitted to our hospital were confirmed to have bacteremia caused by S. pettenkoferi, which was identified in blood cultures using Vitek MS (bioMérieux). Therefore, we recommend using the Vitek MS (bioMérieux) for rapid and accurate identification of the pathogen causing bloodstream infection when CoNS is suspected.
Subject(s)
Humans , Bacteremia , Immunocompromised Host , StaphylococcusABSTRACT
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
No abstract available.
Subject(s)
Aged , Female , Humans , Aneurysm/surgery , Anti-Bacterial Agents/pharmacology , Brain Diseases/surgery , Craniotomy/adverse effects , DNA, Bacterial/chemistry , Flavobacteriaceae Infections/etiology , Flavobacterium/classification , Meningitis/diagnosis , Microbial Sensitivity Tests , Phylogeny , Postoperative Complications , Sequence Analysis, DNAABSTRACT
A 73-year-old man visited our hospital because of pain with swelling and redness on the right foot dorsum. He was diagnosed with liver cirrhosis and nodular hepatic cellular carcinoma. Lower extremity CT scan and MRI showed abscess formation in the right foot dorsum. Gram-negative cocci were recovered from the culture of drained pus at the site and identified as Neisseria skkuensis by 16S rRNA gene sequencing. Here, we report the first case of cellulitis due to N. skkuensis and provide a literature review.
Subject(s)
Aged , Humans , Abscess , Cellulitis , Foot , Genes, rRNA , Liver Cirrhosis , Lower Extremity , Magnetic Resonance Imaging , Neisseria , RNA, Ribosomal, 16S , Sequence Analysis , Suppuration , Tomography, X-Ray ComputedABSTRACT
The 5th year KONSAR surveillance in 2001 was based on routine test data at 30 participating hospitals. It was of particular interest to find a trend in the resistances of enterococci to vancomycin, of Enterobacteriaceae to the 3rd generation cephalosporin and fluoroquinolone, and of Pseudomonas aeruginosa and acinetobacters to carbapenem. Resistance rates of Gram-positive cocci were: 70% of Staphylococcus aureus to oxacillin; 88% and 16% of Enterococcus faecium to ampicillin and vancomycin, respectively. Seventy-two percent of pneumococci were nonsusceptible to penicillin. The resistance rates of Enterobacteriaceae were: Escherichia coli, 28% to fluoroquinolone; Klebsiella pneumoniae, 27% to ceftazidime, and 20% to cefoxitin; and Enterobacter cloacae, > or =40% to cefotaxime and ceftazidime. The resistance rates of P. aeruginosa were 21% to ceftazidime, 17% to imipenem, and those of the acinetobacters were > or =61% to ceftazidime, aminoglycosides, fluoroquinolone and cotrimoxazole. Thirty-five percent of non-typhoidal salmonellae were ampicillin resistant, and 66% of Haemophilus influenzae were -lactamase producers. Notable changes over the 1997-2001 period were: increases in vancomycin-resistant E. faecium, and amikacin- and fluoroquinolone-resistant acinetobacters. With the increasing prevalence of resistant bacteria, nationwide surveillance has become more important for optimal patient management, for the control of nosocomial infection, and for the conservation of the newer antimicrobial agents.
Subject(s)
Humans , Anti-Bacterial Agents/pharmacology , Cephalosporins/pharmacology , Drug Resistance, Microbial , Enterococcus faecium/metabolism , Imipenem/pharmacology , Klebsiella pneumoniae/metabolism , Korea , Pseudomonas aeruginosa/metabolism , Time Factors , Vancomycin/pharmacologyABSTRACT
Although Malassezia furfur is normal skin flora causing superficial skin diseases, cases of fungemia have been reported recently in premature newborns or immunocompromised patients related to prolonged central venous catheterization for lipid supplementation. We report a case of M. furfur fungemia in a premature infant receiving intravenous lipid supplementation through central venous circulation. She was treated only with antifungal agents without removal of the catheter or discontinuation of lipid supplementation. Soon after, symptoms and signs of the patient seemed to be improved. However, central venous catheter was removed because of recurrent septicemia of Staphylococcus aureus and the culture of central venous catheter tip showed colonization of M. furfur.