• Laboratory Medicine Online
• /
• v.7 no.4
• /
• pp.163-169
• /
• 2017

Background: An automated immunohematology analyzer, DAYMATE M (DAY Medical, Switzerland), has been recently developed. The potential of this analyzer to improve test results has been evaluated. Methods: A total of 300 blood samples from Seoul St. Mary's hospital and Incheon St. Mary's hospital were tested for ABO and RhD typing. In addition, 336 antibody screening test (AST) samples and 82 patients treated with hematopoietic stem cell transplantation (HSCT) were included. AST results by DAYMATE M were compared with those obtained by a manual method using DS-Screening II (Bio-Rad Laboratories, Switzerland) and red blood cells from Selectogen (Ortho-Clinical diagnostics Inc., USA). Results: Of the 300 patients enrolled, 87, 73, 79, and 61 had type A, B, O, and AB blood, respectively. The concordance rate was 99.9% for cell typing and 97.0% for serum typing. One discordant case was classified as type B instead of AB, and six discordant serum-typing cases were type A, but classified as type AB. Among the 336 AST samples, the concordance rate was 93.2%. From 136 positive cases, six were discordant. Within the 82 HSCT-treated patients, the concordance rate for ABO blood typing was 92.2%. Among the six discordant cases, DAYMATE M typed four cases as donor type where the standard method typed them as the recipient blood type. Conclusions: The DAYMATE M automated immunohematology analyzer performs reliably for ABO and RhD typing, as well as for ASTs and on samples from patients treated with HSCT.

• Laboratory Medicine Online
• /
• v.7 no.1
• /
• pp.13-19
• /
• 2017

Background: We evaluated a sensitive and quantitative method utilizing fragment analysis of the fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), simultaneously measuring mutant allele burden and length, and verified the analytical performance. Methods: The number and allelic burden of FLT3-ITD mutations was determined by fragment analysis. Serial mixtures of mutant and wild-type plasmid DNA were used to calculate the limit of detection of fragment analysis, conventional PCR, and Sanger sequencing. Specificity was evaluated using DNA samples derived from 50 normal donors. Results of fragment analysis were compared to those of conventional PCR, using 481 AML specimens. Results: Defined mixtures were consistently and accurately identified by fragment analysis at a 5% relative concentration of mutant to wild-type, and at 10% and 20% ratios by conventional PCR and direct sequencing, respectively. No false positivity was identified. Among 481 AML specimens, 40.1% (193/481) had FLT3-ITD mutations. The mutant allele burden (1.7-94.1%; median, 28.2%) and repeated length of the mutation (14-153 bp; median, 49 bp) were variable. The concordance rate between fragment analysis and conventional PCR was 97.7% (470/481). Fragment analysis was more sensitive than conventional PCR and detected 11 additional cases: seven had mutations below 10%, three cases represented conventional PCR failure, and one case showed false negativity because of short ITD length (14 bp). Conclusions: The new fragment analysis method proved to be sensitive and reliable for the detection and monitoring of FLT3-ITD in patients with AML. This could be used to simultaneously assess ITD mutant allele burden and length.

• Pediatric Infection and Vaccine
• /
• v.28 no.2
• /
• pp.92-100
• /
• 2021

Purpose: Rapid detection of etiologic organisms is crucial for initiating appropriate therapy in patients with central nervous system (CNS) infection. This study aimed to evaluate the diagnostic value of the BioFire^® Meningitis/Encephalitis (ME) panel in detecting etiologic organisms in cerebrospinal fluid (CSF) samples from febrile infants. Methods: CSF samples from infants aged <90 days who were evaluated for fever were collected between January 2016 and July 2019 at the Seoul National University Children's Hospital. We performed BioFire^® ME panel testing of CSF samples that had been used for CSF analysis and conventional tests (bacterial culture, Xpert^® enterovirus assay, and herpes simplex virus-1 and -2 polymerase chain reaction) and stored at -70℃ until further use. Results: In total, 72 (24 pathogen-identified and 48 pathogen-unidentified) CSF samples were included. Using BioFire^® ME panel testing, 41 (85.4%) of the 48 pathogen-unidentified CSF samples yielded negative results and 22 (91.7%) of the 24 pathogen-identified CSF samples yielded the same results (enterovirus in 19, Streptococcus agalactiae in 2, and Streptococcus pneumoniae in 1) as those obtained using the conventional tests, thereby resulting in an overall agreement of 87.5% (63/72). Six of the 7 pathogen-unidentified samples were positive for human parechovirus (HPeV) via BioFire^® ME panel testing. Conclusions: Compared with the currently available etiologic tests for CNS infection, BioFire^® ME panel testing demonstrated a high agreement score for pathogen-identified samples and enabled HPeV detection in young infants. The clinical utility and cost-effectiveness of BioFire^® ME panel testing in children must be evaluated for its wider application.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.26 no.1
• /
• pp.42-46
• /
• 2022

Purpose In the meantime, there have been not many samples that require dilution, and it has been difficult for the examiner to set an appropriate dilution multiple for RIA test item and report the results. Accordingly, it was judged that it was necessary to set the maximum dilution multiple for each test and to verify the upper limit of the clinical reportable range. Therefore, in this study, the maximum dilution multiple for each RIA test was set and the upper limit of the clinical reportable range was verified accordingly Materials and Methods Among all RIA tests conducted at Asan Medical Center, the study treated on 30 types of tests which also conduct the dilution test. Data from March to July 2021 were collected and analyzed. The study was conducted on samples subjected to serial dilutions such as X2, X4 or X10, X10², X10³, X10⁴, X10⁵. Results Among a total of 30 test types, 18 test types have more than 5 N values in the tolerance range of 80~120%. As a result of the verification of maximum dilution multiples, the test set to 10⁴ is 𝛼-fetoprotein and thyroglobulin, and the test set to 10³ is CA-125, CEA, and 𝛽-hCG, and the test set to 10² is Free PSA, PSA, CA15-3, SCC, Ferritin, PTH, Cortisol, and Calcitonin. Tests set to 10 include three categories: 𝛽2-Microglobulin, C-peptide, and Testosterone. Conclusion It is expected that it will contribute to improving the quality of nuclear medicine blood tests as the results of dilution experiments can be reported quickly and accurately through the verification of the clinical reportable range.

• Tuberculosis and Respiratory Diseases
• /
• v.44 no.1
• /
• pp.114-123
• /
• 1997

Background : To assess the diagnostic role of bronchoscopic lavage for the evaluation of pneumonia in intensive care unit(ICU), the results were compared to blind endobronchial specimen. Method : From September 1993 to August 1996, twenty-eight ICU patients suspected pneumonia on the basis of clinical evidence and performed bronchoscopy under the diagnostic or therapeutic purpose were studied retrospectively for the clinical findings including culture of bronchoscopic and blind endobronchial specimen. Bronchoscopic specimen was got through small amount of bronchoalveolar lavage with 20-40ml saline, one or two times on the suspected site. Results : l. Main reasons of ICU admission were respiratory and impending respiratory failure Nosocomial pneumonia was most common with 16 cases; each for community acquired and immunocompromised type with 6 cases. Diagnostic purpose of bronchoscopy was performed in 20 cases as 71 percent in total, whereas therapeutic removal of secretion in 8 cases. The complication during bronchoscopic evaluation was trivial. 2. The agreement between blind endobronchial and bronchoscopic specimen on microbial culture was only 39.3 percent. However, 2 cases each for aspergillosis and tuberculosis were diagnosed under bronchoscopic evaluation. 3 The application of mechanical ventilation occured significantly frequently in multidrug resistant pneumonia compared with other pneumonia in terms of bronchoscopic specimen. 4. The application of mechanical ventilation was significantly common in nosocomial pneurmonia compared with other types of pneumonia. Conclusion : The selective bronchoalveolar lavage and therapeutic removal of bronchial secretion with bronchoscopy in ICU patient accompanying pneumonia is a very useful tool with safety. The multidrug resistant pneumonia or nosocomial pneumonia could be closely associated with the use of mechanical ventilation.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.1
• /
• pp.116-119
• /
• 2009

Background: Preanalytical factors can affect reliability of hormone assay results. Adrenocorticotropic hormone (ACTH) in blood is considered highly unstable because of proteolytic degradation, so storage of blood samples on ice until analysis is recommended. In clinical practice, however, this procedure may present logistical problems because most samples for ACTH measurement must be shipped from the place of sample collection to the laboratory. Therefore, we studied the impact of time and temperature before plasma separation and analysis on the results of ACTH assays. Methods: A total number of 22 patients were enrolled in this study. We obtained 2 blood samples. ACTH concentrations were 35~126 pg/mL. ACTH concentrations were measured by immunoradiometric assay (IRMA) using commercial kits (CIS Biointernational, Gif-sur-Yvette, France). Results: ACTH levels showed a significant difference between the samples of $22^{\circ}C$ EDTA and $4^{\circ}C$ EDTA. Measured ACTH concentrations significantly decreased with time before freezing at $-20^{\circ}C$. ACTH levels showed no significant difference between the groups of after storage for 24 hr without centrifugation at $22^{\circ}C$ and $4^{\circ}C$. Conclusion: We recommend that blood samples be obtained on pre-chilled EDTA collection tubes. The shortest possible time between sample collection and processing is always the best laboratory practice.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.7
• /
• pp.965-970
• /
• 2003

This study has been performed to develope a method for the simultaneous determination of 1,4-dioxane (DOX), epichlorohydrin (EPC), propylene chlorohydrin (PCH), ethylene chlorohydrin (ECH) and 1,3-dichloro-2-pro-panol (DCP) in polysorbates, chloline chloride, choline bitartrate, modified starch and spices by purge and trapgas chromatography. Experimental design was used to select a suitable trap by measuring the limit of detection (LOD) and to investigate the effect of temperature and salt of extraction, and the percentage of recovery in various matrix. The LOD of DOX, EPC, PCH, ECH and DCP were 1.38$\mu\textrm{g}$, 0.23$\mu\textrm{g}$, 3.30$\mu\textrm{g}$, 3.97$\mu\textrm{g}$, 20.43$\mu\textrm{g}$ respectively, by means of using Vorcarb 3000 trap with 5$0^{\circ}C$ sample sparger. Excluding EPC, the recoveries of target compounds were above 90% in all matrix. Target compounds in polysorbates (17), choline chloride (5), choline bitartrate (5), modified starch (8) and spices (25) were not detected. But 2.5 ppm of DOX was detected in Tween 80.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.9 no.2
• /
• pp.147-152
• /
• 2006

Purpose: Efficacy of the new rotavirus vaccines ($Rotarix^{(R)}$, $RotaTeq^{(R)}$) recently developed can be affected by the rotavirus genotypes prevalent in communities. We performed this study to identify the recent distribution of rotavirus genotypes prevalent in Jeju. Methods: Genotyping of human rotaviruses was performed using 81 samples collected from 154 inpatients and outpatients with rotavirus gastroenteritis at Cheju National University Hospital between July 2005 and June 2006. All six (1, 2, 3, 4, 8, 9) G serotypes were identified by amplification of segments of the gene for VP7 using the reverse transcription-polymerase reaction (RT-PCR). Results: The results of RT-PCR for 81 samples were all positive. G typing of the VP7 protein showed that G1 was the most dominant circulating genotype (65.5%) followed by G2 (14.8%), G3 (13.6%), G8 (1.2%), G9 (1.2%), G4 (0%), and a combination of G1/G3 (3.7%). Conclusion: This distribution of rotavirus VP7 genotypes in Jeju is different from that in other domestic areas; the most dominant circulating genotype was G1.

• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.2
• /
• pp.110-117
• /
• 2018

In the present study, mec complex typing and SCCmec typing were performed to analyze the molecular genetic characteristics of 20 methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from clinical specimens and 4 strains isolated from the ICU environments of secondary medical institutions in a Chungnam province, Korea, from June to July of 2017. Among a total of 20 MRSA strains isolated from clinical specimens, 8 cases (40%) were SCCmec type II, one case (5%) was SCCmec type IVa, and 11 cases (55%) were not-typeable in SCCmec type analysis. Among 4 MRSA isolates from the ICU environment, one strain did not have the mecA gene and 3 strains were typed as SCCmec types II, III, and IVa, respectively. Data from the present study showed that the origin of MRSA isolated from the clinical specimens was different from those from the ICU environment in most cases but the origin was concordant in one case. In this case, MRSA might be transmitted by healthcare workers to the ICU environment. Further study with a large number of cases and other hospital infection-related microorganisms will be needed. This continuous follow-up study might provide useful information on infection control in medical institutions.

• Journal of Yeungnam Medical Science
• /
• v.8 no.1
• /
• pp.42-52
• /
• 1991

Two types of urine dipstick assays, Multistix-SG and Combur-9-test RL, were compared for compatibility, accuracy, specificity and predictive values of a positive and negative test in 501 patients urine and artificially prepared specimen. We found that the results of semiquantitative tests of Multistix-SG and Combur-9-Test RL performed were statistically similar in patients specimen. The urinary leukocyte estrase tests of Combur-9-Test RL assays compared with urine sediment microscopy in regard to compatibility, sensitivity, specificity, and predictive values of a positive and negative test 83.7%, 48.1%, 90.3%, 47.4% and 90.1%, respectively. The urinar nitrite tests of Comber-9-Test RL assays compared with urine culture tests, in regard to compatibility, sensitivity, specificity, and predictive values of a positive and negative tests were 90.3%, 19.4%, 84.7%, 53.8% and 94.1%, respectively. For the urinary protein, the sulfosalicylic acid method was the most sensitive test for any kinds of protein, and Multistix-SG appeared more sensitive than Compur-9-Test RL for the albuminuria. For the urinary bilirubin and glusose, two dipstick assays were similar in their diganostic efficiency. Finally in the urinary occult blood tests, Combur-9-Test RL assays was more sensitive than Multistix-SG.