Analysis of blood culture data in Korea: bacterial distribution and cumulative antimicrobial resistance (2016–2020) / 대한임상미생물학회지

Background@#The distribution of bacteria isolated from bloodstream infections and cumulative antimicrobial susceptibility data are the basis for empirical decisions regarding antibiotics as an initial treatment. Therefore, it is important to consistently collect blood culture results of individual patients and analyze them correctly. @*Methods@#The blood culture results of patients at a university hospital from 2016 to 2020 were analyzed retrospectively to determine the bacterial distributions and antibiotic resistance patterns. Duplicates were eliminated by including only the first isolate of each species per patient. @*Results@#Escherichia coli (27.1%) was the most commonly isolated bacterium from blood cultures, followed by Klebsiella pneumoniae (10.1%) and Staphylococcus aureus (8.6%). The methicillin resistance rate of S. aureus was 49.2%, and the vancomycin resistance rate of Enterococcus faecium was 39.5%; with no significant changes over the study period. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of E. coli were 35.0%, 46.8%, and 0.7%, respectively. Seventeen carbapenem-resistant E. coli strains were isolated, of which 11 produced carbapenemase. The cefotaxime, ciprofloxacin, and ertapenem resistance rates of K. pneumoniae were 29.5%, 31.7%, and 5.4%, respectively. Forty-eight carbapenem-resistant K. pneumoniae strains were isolated, of which 37 produced carbapenemase. The imipenem resistance rates of Acinetobacter baumannii and Pseudomonas aeruginosa were 72.3% and 23.4%, respectively. @*Conclusion@#In the blood culture results from 2016 to 2020, the isolation frequency of E.coli, K. pneumoniae, and E. faecium showed an increasing trend, whereas that of S. aureus was stable. Over the 5 year study period, the ciprofloxacin resistance rate of E. coli and P.aeruginosa and ampicillin/sulbactam resistance rate of A. baumannii significantly increased.

Transfusion in RhD Mismatch Hematopoietic Stem Cell Transplantation / 대한수혈학회지

In some cases, hematopoietic stem cell transplants (HSCT) show differences in the D antigen. In previous studies, there have been few cases of de novo anti-D alloimmunization, and even rarer cases of serious side effects or the outcomes. De novo anti-D alloimmunization has been reported to occur more frequently in minor D mismatch than in major D mismatch. For the RhD type of blood components, RhD-negative type is recommended in transfusion in RhD mismatch HSCT without anti-D in donors and recipients. But in situations of insufficient RhD-negative blood supply, this study suggests that the RhD type of blood components depends on the patients’ RhD type before transplantation, and it depends on the donors’ RhD type after transplantation, and an RhD-positive platelet transfusion may be available.

Performance of Copeptin for Early Diagnosis of Acute Myocardial Infarction in an Emergency Department Setting

BACKGROUND@#Rapid and accurate diagnosis of acute myocardial infarction (AMI) is critical for initiating effective treatment and achieving better prognosis. We investigated the performance of copeptin for early diagnosis of AMI, in comparison with creatine kinase myocardial band (CK-MB) and troponin I (TnI).@*METHODS@#We prospectively enrolled 271 patients presenting with chest pain (within six hours of onset), suggestive of acute coronary syndrome, at an emergency department (ED). Serum CK-MB, TnI, and copeptin levels were measured. The diagnostic performance of CK-MB, TnI, and copeptin, alone and in combination, for AMI was assessed by ROC curve analysis by comparing the area under the curve (AUC). Sensitivity, specificity, negative predictive value, and positive predictive value of each marker were obtained, and the characteristics of each marker were analyzed.@*RESULTS@#The patients were diagnosed as having ST elevation myocardial infarction (STEMI; N=43), non-ST elevation myocardial infarction (NSTEMI; N=25), unstable angina (N=78), or other diseases (N=125). AUC comparisons showed copeptin had significantly better diagnostic performance than TnI in patients with chest pain within two hours of onset (AMI: P=0.022, ≤1 hour; STEMI: P=0.017, ≤1 hour and P=0.010, ≤2 hours). In addition, TnI and copeptin in combination exhibited significantly better diagnostic performance than CK-MB plus TnI in AMI and STEMI patients.@*CONCLUSIONS@#The combination of TnI and copeptin improves AMI diagnostic performance in patients with early-onset chest pain in an ED setting.

Performance Evaluation of the Preanalytic Module of the ACL TOP 750 Hemostasis Lab System

No abstract available.

Eosinophilic Meningitis after Bovine Graft Duraplasty for Arnold-Chiari Malformation Type 1 in a 33-year-old Man

Cases of pediatric eosinophilic meningitis following duraplasty with a bovine graft have been reported. These patients recovered following the surgical removal of the dural graft or steroid therapy. Decompression for Chiari malformation is a common procedure in both pediatric and adult neurosurgery. We describe the case of a 33-yr-old male patient with eosinophilic meningitis following Chiari decompression via bovine graft duraplasty. Cerebrospinal fluid (CSF) study showed 49 red blood cells/μL and 129 leukocytes/μL with 17% eosinophils. There was no evidence of infectious disease. To our knowledge, this is the first report of adult eosinophilic meningitis after bovine graft duraplasty in Korea.

Analysis of Blood Culture Data at a Tertiary University Hospital, 2006-2015 / 대한임상미생물학회지

BACKGROUND: Cumulative blood culture data provide clinicians with important information in the selection of empiric therapy for blood stream infections. METHODS: We retrospectively analyzed blood culture data from a university hospital during the period from 2006 to 2015. Only the initial isolates of a given species for each patient were included. RESULTS: The number of blood cultures per 1,000 inpatient-days increased from 64 in 2006 to 117 in 2015. The ratio of significant pathogens to total isolates was 0.56-0.63. The most common organisms were Escherichia coli in 2006-2010 but changed to coagulase-negative staphylococci (CoNS) in 2011. The proportion of Staphylococci aureus was decreased during the study period, but Klebsiella pneumoniae was increased. Enterococci were increased, especially E. faecium, which was more frequently isolated than E. faecalis in 2015. Pseudomonas aeruginosa was decreased during the study, but Acinetobacter baumannii was increased. The prevalence of methicillin-resistant S. aureus (MRSA) changed from 62.2% to 53.9%, while vancomycin-resistant E. faecium increased to 35.8%. Extended-spectrum beta-lactamase (ESBL)-producing E. coli and K. pneumoniae increased to 25% and 34%, respectively, in 2015. Starting in 2008, three E. coli and 11 K. pneumoniae isolates were carbapenem-resistant Enterobacteriaceae (CRE), and three were carbapenemase-producing Enterobacteriaceae (CPE). The prevalence of imipenem-resistant A. baumannii rapidly increased during the study period. CONCLUSION: About 60% of all blood isolates were significant pathogens. The most common isolates changed from E. coli to CoNS in 2011. ESBL-producing E. coli and K. pneumoniae, vancomycin-resistant E. faecium, and imipenem-resistant A. baumannii were increased during the study, while the proportion of MRSA tended to decrease slightly. Of the total isolates, 14 were CRE, and 3 were CPE.

Multiple Brain Abscesses Caused by Nocardia asiatica in a Patient With Systemic Lupus Erythematosus: The First Case Report and Literature Review

No abstract available.

Ahcyl2 upregulates NBCe1-B via multiple serine residues of the PEST domain-mediated association

Inositol-1,4,5-triphosphate [IP3] receptors binding protein released with IP3 (IRBIT) was previously reported as an activator of NBCe1-B. Recent studies have characterized IRBIT homologue S-Adenosylhomocysteine hydrolase-like 2 (AHCYL2). AHCYL2 is highly homologous to IRBIT (88%) and heteromerizes with IRBIT. The two important domains in the N-terminus of AHCYL2 are a PEST domain and a coiled-coil domain which are highly comparable to those in IRBIT. Therefore, in this study, we tried to identify the role of those domains in mouse AHCYL2 (Ahcyl2), and we succeeded in identifying PEST domain of Ahcyl2 as a regulation region for NBCe1-B activity. Site directed mutagenesis and coimmunoprecipitation assay showed that NBCe1-B binds to the N-terminal Ahcyl2-PEST domain, and its binding is determined by the phosphorylation of 4 critical serine residues (Ser151, Ser154, Ser157, and Ser160) in Ahcyl2 PEST domain. Also we revealed that 4 critical serine residues in Ahcyl2 PEST domain are indispensable for the activation of NBCe1-B using measurement of intracellular pH experiment. Thus, these results suggested that the NBCe1-B is interacted with 4 critical serine residues in Ahcyl2 PEST domain, which play an important role in intracellular pH regulation through NBCe1-B.

Acute myeloid leukemia with t(4;12)(q12;p13): report of 2 cases

No abstract available.

Bone Marrow Oxalosis in a Patient With Pancytopenia Following Bilateral Nephrectomy

No abstract available.

The Prognostic Value of Serum Levels of Heart-Type Fatty Acid Binding Protein and High Sensitivity C-Reactive Protein in Patients With Increased Levels of Amino-Terminal Pro-B Type Natriuretic Peptide

BACKGROUND: Amino-terminal pro-B type natriuretic peptide (NT-proBNP) is a well-established prognostic factor in heart failure (HF). However, numerous causes may lead to elevations in NT-proBNP, and thus, an increased NT-proBNP level alone is not sufficient to predict outcome. The aim of this study was to evaluate the utility of two acute response markers, high sensitivity C-reactive protein (hsCRP) and heart-type fatty acid binding protein (H-FABP), in patients with an increased NT-proBNP level. METHODS: The 278 patients were classified into three groups by etiology: 1) acute coronary syndrome (ACS) (n=62), 2) non-ACS cardiac disease (n=156), and 3) infectious disease (n=60). Survival was determined on day 1, 7, 14, 21, 28, 60, 90, 120, and 150 after enrollment. RESULTS: H-FABP (P<0.001), NT-proBNP (P=0.006), hsCRP (P<0.001) levels, and survival (P<0.001) were significantly different in the three disease groups. Patients were divided into three classes by using receiver operating characteristic curves for NT-proBNP, H-FABP, and hsCRP. Patients with elevated NT-proBNP (≥3,856 pg/mL) and H-FABP (≥8.8 ng/mL) levels were associated with higher hazard ratio for mortality (5.15 in NT-proBNP and 3.25 in H-FABP). Area under the receiver operating characteristic curve analysis showed H-FABP was a better predictor of 60-day mortality than NT-proBNP. CONCLUSIONS: The combined measurement of H-FABP with NT-proBNP provides a highly reliable means of short-term mortality prediction for patients hospitalized for ACS, non-ACS cardiac disease, or infectious disease.

Massive Transfusion Protocols for Pediatric Patients

The number of massive transfusions for pediatric patients has risen owing to the increasing number of complex surgeries and trauma centers. However, as there are only a few studies on pediatric massive transfusion, adult massive transfusion protocols are used for pediatric patients in many hospitals and institutions. Although massive transfusion protocols would improve the outcomes and reduce the received blood products during transfusion, pediatric patients differ from adults in the tolerability to transfusion, incidence of coagulopathy, and mechanisms of injuries. Therefore clinical physicians have requested for a pediatric massive transfusion protocol. Herein, we reviewed pediatric massive transfusion protocols that have been used in various clinical settings. To date, only a few single-center studies with a small number of pediatric patients have been performed. Even though these studies did not show improvement in outcomes such as mortality and side effects, they reported a short preparation time for fresh frozen plasma products and a low coagulopathy rate in pediatric massive transfusion groups. Therefore, large, prospective, multicenter studies are needed to identify the empiric ratio of blood products for improving outcomes of pediatric patients who need massive transfusion.

Screening PCR Versus Sanger Sequencing: Detection of CALR Mutations in Patients With Thrombocytosis

BACKGROUND: Mutations in calreticulin (CALR) have been reported to be key markers in the molecular diagnosis of myeloid proliferative neoplasms. In most previous reports, CALR mutations were analyzed by using Sanger sequencing. Here, we report a new, rapid, and convenient system for screening CALR mutations without sequencing. METHODS: Eighty-three bone marrow samples were obtained from 81 patients with thrombocytosis. PCR primers were designed to detect wild-type CALR (product: 357 bp) and CALR with type 1 (product: 302 bp) and type 2 mutations (product: 272 bp) in one reaction. The results were confirmed by Sanger sequencing and compared with results from fragment analysis. RESULTS: The minimum detection limit of the screening PCR was 10 ng for type 1, 1 ng for type 2, and 0.1 ng for cases with both mutations. CALR type 1 and type 2 mutants were detected with screening PCR with a maximal analytical sensitivity of 3.2% and <0.8%, respectively. The screening PCR detected 94.1% (16/17) of mutation cases and showed concordant results with sequencing in the cases of type 1 and type 2 mutations. Sanger sequencing identified one novel mutation (c.1123_1132delinsTGC). Compared with sequencing, the screening PCR showed 94.1% sensitivity, 100.0% specificity, 100.0% positive predictive value, and 98.5% negative predictive value. Compared with fragment analysis, the screening PCR presented 88.9% sensitivity and 100.0% specificity. CONCLUSIONS: This screening PCR is a rapid, sensitive, and cost-effective method for the detection of major CALR mutations.

Unexpected Antibody Screening Tests Including Di(a) in Patients with a History of Multiple Packed Red Cell Transfusion / 대한수혈학회지

BACKGROUND: The Di(a) antigen has been detected with a relatively higher incidence among Koreans with a frequency of 6.4 to 14.5%. In South Korea, commonly used unexpected antibody screening panels do not include Di(a) antigen positive cells. We screened patients who previously received multiple packed red cell transfusion using two cells without Di(a) antigen and three cells including Di(a) antigen to evaluate the effectiveness of three screening cells. METHODS: A total of 307 patients who had received packed red cell transfusion more than three times during the last 6 months in our hospital were enrolled. They were employed for unexpected antibody screening test using two sets of screening cells not including Di(a) antigen and three sets including Di(a) antigen by LISS/Coombs gel card. RESULTS: Among 307 patients, 12 were positive using two cells and 15 were positive using three cells. Three patients showed discordant result and one of them was positive for the cell including Di(a) antigen (0.33%). Antibody identification was performed using the panel which does not include Di(a) antigen and it was negative for all of the antigens listed on the panel so that the presence of anti-Di(a) was suspected. CONCLUSION: It can be difficult to use three cells including Di(a) antigen for all patients due to cost, however, use of three cells is recommended in patients with multiple transfusion history.

Hepcidin Level and Iron Parameters in Patients with Chronic Kidney Disease

BACKGROUND: Hepcidin, a key regulator of iron homeostasis, is associated with iron metabolism imbalance in patients with chronic kidney disease (CKD). However, serum hepcidin level in anemic patients with CKD presents a contradictory picture. We investigated the relationship between serum hepcidin-25 level and iron parameters in patients with CKD. METHODS: We defined and categorized patients with CKD according to the Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines. We analyzed the relationship between serum hepcidin-25 level and iron parameters [serum iron, total iron-binding capacity (TIBC), unbound iron-binding capacity (UIBC), transferrin saturation, and ferritin levels] according to the CKD stage and clinical and laboratory characteristics. RESULTS: Hb level, TIBC, and UIBC decreased and ferritin level increased (Ptrend0.05). CONCLUSIONS: Serum hepcidin-25 level was not found to be associated with iron parameters or clinical status of CKD patients in our study. Determination of hepcidin-25 levels may not provide more information than conventional iron parameters in monitoring iron metabolism in CKD patients. However, further studies are needed to establish the clinical utility of hepcidin measurement in CKD patients.

Evaluation of AutoLab Rapid Plasma Reagin and AutoLab Treponema pallidum Latex Agglutination for Syphilis Infection Testing / 임상검사와정도관리

BACKGROUND: Automated assays have recently been developed for efficient serological testing of syphilis infection. Here, we evaluate the performance of new automated serological assays for syphilis infection. METHODS: The precision, linearity, and detection limit of the automated kits AutoLab rapid plasma reagin (RPR) (IVD-RPR) and AutoLab (Treponema pallidum Latex Agglutination) TPLA (IVD-TPLA) (IVDLab Co., Korea) were evaluated using an immunoturbidimetric method. In addition, the results of these tests were compared with those obtained using the HiSens Auto RPR LTIA (HBi-RPR) and HiSens Auto TP LTIA (HBi-TPLA) tests (HBi Co., Korea) with 122 serum samples. RESULTS: Both the IVD-RPR and IVD-TPLA kits showed acceptable precision for the positive controls (IVDLab Co., Korea). The within-run and total precision of IVD-RPR were better than those of HBi-RPR at cut-off levels (CV, 7.0% to 7.4% for IVD-RPR; CV, 33.3% to 40.0% for HBi-RPR). The IVD-RPR and IVD-TPLA kits demonstrated acceptable linearity and limits of detection. The agreement rate between IVD-RPR and HBi-RPR was 83.60% (102/122). Nineteen samples were IVD-RPR negative but HBi-RPR positive; 12 of these were from patients with a history of syphilis. The agreement rate between IVD-TPLA and HBi-TPLA was 96.72% (118/122). All discrepant results were IVD-TPLA positive and HBi-TPLA negative. CONCLUSIONS: IVD-RPR and IVD-TPLA exhibited acceptable precision, linearity, and limits of detection for the diagnosis of syphilis infection. IVD-RPR was suitable for monitoring syphilis infections with good precision that was near cut-off levels. IVD-TPLA was useful for detecting primary syphilis infection.

A Case of Isolated Lymphoblastic Relapse of the Central Nervous System in a Patient with Chronic Myelogenous Leukemia Treated with Imatinib

No abstract available.

Fatal Pulmonary Mucormycosis Caused by Rhizopus microsporus in a Patient with Diabetes

No abstract available.

N-ras Mutation Detection by Pyrosequencing in Adult Patients with Acute Myeloid Leukemia at a Single Institution

BACKGROUND: N-ras mutations are one of the most commonly detected abnormalities of myeloid origin. N-ras mutations result in a constitutively active N-ras protein that induces uncontrolled cell proliferation and inhibits apoptosis. We analyzed N-ras mutations in adult patients with AML at a particular institution and compared pyrosequencing analysis with a direct sequencing method for the detection of N-ras mutations. METHODS: We analyzed 90 bone marrow samples from 83 AML patients. We detected N-ras mutations in codons 12, 13, and 61 using the pyrosequencing method and subsequently confirmed all data by direct sequencing. Using these methods, we screened the N-ras mutation quantitatively and determined the incidence and characteristic of N-ras mutation. RESULTS: The incidence of N-ras mutation was 7.2% in adult AML patients. The patients with N-ras mutations showed significant higher hemoglobin levels (P=0.022) and an increased incidence of FLT3 mutations (P=0.003). We observed 3 cases with N-ras mutations in codon 12 (3.6%), 2 cases in codon 13 (2.4%), and 1 case in codon 61 (1.2%). All the mutations disappeared during chemotherapy. CONCLUSIONS: There is a low incidence (7.2%) of N-ras mutations in AML patients compared with other populations. Similar data is obtained by both pyrosequencing and direct sequencing. This study showed the correlation between the N-ras mutation and the therapeutic response. However, pyrosequencing provides quantitative data and is useful for monitoring therapeutic responses.

N-ras Mutation Detection by Pyrosequencing in Adult Patients with Acute Myeloid Leukemia at a Single Institution

BACKGROUND: N-ras mutations are one of the most commonly detected abnormalities of myeloid origin. N-ras mutations result in a constitutively active N-ras protein that induces uncontrolled cell proliferation and inhibits apoptosis. We analyzed N-ras mutations in adult patients with AML at a particular institution and compared pyrosequencing analysis with a direct sequencing method for the detection of N-ras mutations. METHODS: We analyzed 90 bone marrow samples from 83 AML patients. We detected N-ras mutations in codons 12, 13, and 61 using the pyrosequencing method and subsequently confirmed all data by direct sequencing. Using these methods, we screened the N-ras mutation quantitatively and determined the incidence and characteristic of N-ras mutation. RESULTS: The incidence of N-ras mutation was 7.2% in adult AML patients. The patients with N-ras mutations showed significant higher hemoglobin levels (P=0.022) and an increased incidence of FLT3 mutations (P=0.003). We observed 3 cases with N-ras mutations in codon 12 (3.6%), 2 cases in codon 13 (2.4%), and 1 case in codon 61 (1.2%). All the mutations disappeared during chemotherapy. CONCLUSIONS: There is a low incidence (7.2%) of N-ras mutations in AML patients compared with other populations. Similar data is obtained by both pyrosequencing and direct sequencing. This study showed the correlation between the N-ras mutation and the therapeutic response. However, pyrosequencing provides quantitative data and is useful for monitoring therapeutic responses.