1.Gelatinous transformation of the bone marrow in hepatocellular carcinoma.
Jeonghyun CHANG ; Chan Jeoung PARK
Blood Research 2015;50(2):71-71
No abstract available.
Bone Marrow*
;
Carcinoma, Hepatocellular*
;
Gelatin*
2.Isolation of Anti-D after Administration of Intravenous Immune Globulin in a Patient with Immune Thrombocytopenic Purpura.
Jeonghyun CHANG ; Hee Jung KIM ; Hoi Joo YANG ; Seog Woon KWON
Korean Journal of Blood Transfusion 2013;24(3):286-290
Intravenous immune globulin (IVIG) is widely used in treatment of hypogammablobulinemia and for immunomodulation. Passive transfer of anti-D activity through administration of IVIG may cause difficulty in serologic assessment of patients. Here we report on a case of passive anti-D from IVIG in a D positive patient. The patient was a 72-year-old Korean woman who was hospitalized for refractory immune thrombocytopenic purpura that is not cured after steroid therapy. IVIG 6,000 mg was administered for treatment of immune thrombocytopenic purpura. After IVIG administration for two days, we identified anti-D in the patient and a positive direct antiglobulin test was demonstrated. The patient's hemoglobin level remained unchanged. After IVIG administration for 10 days, the patient's specimen was negative for anti-D, as would be expected with passively acquired antibody. Antibodies in IVIG may confuse and complicate serologic testing of transfusion candidates. Therefore, passive transfer of anti-D should be considered when anti-D is detected, especially when the patient has received IVIG, as in this case.
Aged
;
Antibodies
;
Coombs Test
;
Female
;
Humans
;
Immunoglobulins, Intravenous*
;
Immunomodulation
;
Purpura, Thrombocytopenic, Idiopathic*
;
Serologic Tests
3.A Case of Pneumonia Caused by Pneumocystis jirovecii Resistant to Trimethoprim/Sulfamethoxazole in the Absence of Previous Drug Exposure.
Ari AHN ; Jeonghyun CHANG ; Heungsup SUNG ; Mi Na KIM
Laboratory Medicine Online 2016;6(4):250-254
Pneumocystis jirovecii pneumonia is a common opportunistic infection seen in patients with human immunodeficiency virus (HIV) infection. Dihydropteroate synthase (DHPS) is a target of sulfa drugs, and mutations in DHPS gene are associated with failure in treatment and prophylaxis of P. jirovecii infections in HIV-infected patients. Here, we report a case of a patient with P. jirovecii infection, harboring DHPS gene mutations, who had not been previously treated with trimethoprim/sulfamethoxazole (TMP/SMX). A 50-yr-old man was admitted to the hospital with symptoms such as fever, cough, sputum, and sore throat. Chest computed tomography scanning revealed diffuse ground glass opacity in both the lungs, and the patient was diagnosed as having HIV infection with a CD4+ T cell count of 22/µL. Immunohistochemical test results were positive for P. jirovecii. He was treated with TMP/SMX; however, his symptoms and laboratory findings did not improve. The treatment was changed to clindamycin and primaquine, and his symptoms improved after 3 days. Molecular testing of the sample for the detection of DHPS gene mutations and the typing of mitochondrial large subunit rRNA (mtlsurRNA) revealed DHPS gene mutations at codon 55 and 57, respectively, and the case had type 3 mtlsurRNA. This case study illustrates that DHPS mutation test results can be positive even in patients without previous exposure to TMP/SMX.
Cell Count
;
Clindamycin
;
Codon
;
Cough
;
Dihydropteroate Synthase
;
Fever
;
Glass
;
HIV
;
HIV Infections
;
Humans
;
Lung
;
Opportunistic Infections
;
Pharyngitis
;
Pneumocystis jirovecii*
;
Pneumocystis*
;
Pneumonia*
;
Primaquine
;
Sputum
;
Thorax
4.Practical Aspects of Cytomegalovirus DNA Quantitative PCR.
Jeonghyun CHANG ; Sang Hyun HWANG ; Mi Na KIM ; Heungsup SUNG
Annals of Clinical Microbiology 2017;20(2):21-26
Human cytomegalovirus (CMV) is a clinically important pathogen that causes significant morbidity and mortality in immunocompromised patients and is typically monitored using real-time polymerase chain reaction (real-time PCR). International standards and certified reference materials were recently developed by the WHO, providing the opportunity to standardize viral load reporting. Clinical microbiologists who conduct quantitative CMV DNA testing should be aware of technical issues that can affect the analytical and clinical performance of the method used. These include specimen type, limits of detection and quantification, linear range, reproducibility, and wide variability in viral load values among different assays. Specimen types for testing include whole blood, plasma, serum, and peripheral blood leukocytes. The tests that use whole blood and peripheral blood leukocytes have higher sensitivities. Adsorption chromatography methods are widely used for nucleic acid extraction, and efficiencies can differ between manual and automatic processes. The most common method for quantitative CMV DNA testing is real-time PCR. All CMV testing methods require quality control at the pre-analytic, analytic, and post-analytic stages. In transplant patients, specific quantitative results and monitoring of any changes at follow-up are important. Five to seven days is an adequate follow-up interval in this regard, and drug-resistant CMV should be suspected if there is no response to therapy. One specimen type should be chosen for follow-up quantitative CMV DNA testing, optimized according to WHO standards. Further studies are needed to better standardize CMV testing approaches and to determine the appropriate clinical cut-off level.
Adsorption
;
Chromatography
;
Cytomegalovirus*
;
DNA*
;
Follow-Up Studies
;
Humans
;
Immunocompromised Host
;
Leukocytes
;
Limit of Detection
;
Methods
;
Mortality
;
Plasma
;
Polymerase Chain Reaction*
;
Quality Control
;
Real-Time Polymerase Chain Reaction
;
Viral Load
5.Performance of MALDI Biotyper for Species Identification of Carbapenem-Resistant Enterobacteriaceae by Media Types and Incubation Time.
Young Eun CHO ; Byoung Hu CHOI ; Jeonghyun CHANG ; Heungsup SUNG ; Mi Na KIM
Journal of Laboratory Medicine and Quality Assurance 2018;40(3):155-160
BACKGROUND: This study was conducted to evaluate the impact of the media type used for direct identification of colonies on the surveillance culture of carbapenem-resistant Enterobacteriaceae (CRE) by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). METHODS: CRE surveillance culture isolates were subjected to species identification using the MALDI Biotyper (Bruker Daltonics, Germany) for 2 months starting in March 2017. Four types of media were evaluated: blood agar (BA), Mueller Hinton agar (MH), MacConkey agar (Mac), and MacConkey agar containing imipenem of 1 µg/mL (IMP-Mac). CRE-like colonies on IMP-Mac and their subculture colonies on the other media were tested after overnight incubation and extended incubation for one additional day. The percent identification and score value were analyzed for each media types and incubation time when the identification was correct at the genus level. RESULTS: A total of 117 isolates were identified as 84 Klebsiella pneumoniae, 12 Escherichia coli, 9 Enterobacter cloacae, 5 Klebsiella oxytoca, 4 Enterobacter aerogenes, and 2 Raoultella ornithinolytica. The successful identification rates (SIR) for BA and MH were 98.3% and 97.4% (P=0.9), respectively, while those for Mac and IMP-Mac were 82.1% (P < 0.001) and 70.9% (P < 0.001), respectively. After extended incubation, SIRs were decreased to 96.6%, 96.6% (P=1.0), 61.5% (P < 0.001), and 58.1% (P < 0.001) on BA, MH, Mac, and IMP-Mac, respectively. The average score values were significantly lower for Mac (2.017±0.22) and IMP-Mac (1.978±0.24) than for BA (2.213±0.16) (P < 0.001). CONCLUSIONS: The low performance of the MALDI Biotyper applied directly to the colonies grown on Mac or IMP-Mac indicates that subculture on BA or MH is preferable before identification by MALDI-TOF MS.
Agar
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Enterobacter aerogenes
;
Enterobacter cloacae
;
Enterobacteriaceae*
;
Escherichia coli
;
Imipenem
;
Klebsiella oxytoca
;
Klebsiella pneumoniae
;
Mass Spectrometry
;
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization*
6.Identification of novel susceptibility genes associated with bone density and osteoporosis in Korean women
Bo-Young KIM ; Do-Wan KIM ; Eunkuk PARK ; Jeonghyun KIM ; Chang-Gun LEE ; Hyun-Seok JIN ; Seon-Yong JEONG
Journal of Genetic Medicine 2022;19(2):63-75
Purpose:
Osteoporosis is a common calcium and metabolic skeletal disease which is characterized by decreased bone mass, microarchitectural deterioration of bone tissue and impaired bone strength, thereby leading to enhanced risk of bone fragility.In this study, we aimed to identify novel genes for susceptibility to osteoporosis and/or bone density.
Materials and Methods:
To identify differentially expressed genes (DEGs) between control and osteoporosis-induced cells, annealing control primer-based differential display reverse-transcription polymerase chain reaction (RT-PCR) was carried out in pre-osteoblast MC3T3-E1 cells. Expression levels of the identified DEGs were evaluated by quantitative RT-PCR. Association studies for the quantitative bone density analysis and osteoporosis case-control analysis of single nucleotide polymorphism (SNPs) were performed in Korean women (3,570 subjects) from the Korean Association REsource (KARE) study cohort.
Results:
Comparison analysis of expression levels of the identified DEGs by quantitative RT-PCR found seven genes, Anxa6, Col5a1, Col6a2, Eno1, Myof, Nfib, and Scara5, that showed significantly different expression between the dexamethasontreated and untreated MC3T3-E1 cells and between the ovariectomized osteoporosis-induced mice and sham mice. Association studies revealed that there was a significant association between the SNPs in the five genes, ANXA6, COL5A1, ENO1, MYOF, and SCARA5, and bone density and/or osteoporosis.
Conclusion
Using a whole-genome comparative expression analysis, gene expression evaluation analysis, and association analysis, we found five genes that were significantly associated with bone density and/or osteoporosis. Notably, the association P-values of the SNPs in the ANXA6 and COL5A1 genes were below the Bonferroni-corrected significance level.
7.Status of Pre-analytical Quality Management of Laboratory Tests at Primary Clinics in Korea
Jeonghyun CHANG ; Jinsook LIM ; Jae-Woo CHUNG ; Yong-Hak SOHN ; Min Joong JANG ; Sollip KIM
Annals of Laboratory Medicine 2023;43(5):493-502
Background:
The quality of laboratory test results is crucial for accurate clinical diagnosis and treatment. Pre-analytical errors account for approximately 60%–70% of all laboratory test errors. Laboratory test results may be largely impacted by pre-analytical phase management. However, primary care clinics currently do not have pre-analytical quality management audit systems. We aimed to understand the current status of pre-analytical quality management in laboratory medicine in Korean primary care clinics.
Methods:
Questionnaires were designed to focus on essential components of the pre-analytical process of primary care clinics. An online survey platform was used to administer the survey to internal medicine or family medicine physicians in primary care clinics.
Results:
A total of 141 physicians provided a complete response to the questionnaire. In 65.2% of the clinics, patient information was hand-labeled rather than barcoded on the specimen bottles; 14.2% of clinics displayed only one piece of patient information (name or identification number), and 19.9% of clinics displayed two pieces of information. Centrifuges were not available in 29.1% of the clinics. Institutions carrying out the National Health Screening Program (NHSP) used more barcode system and had more centrifuges than institutions that did not carrying out the NHSP.
Conclusions
Pre-analytical quality management is inadequate in many primary clinics. We suggest implementation of a mandatory management system, allowing for a pre-analytical quality management to be carried out in primary care clinics.
8.Emergence of optrA-Mediated Linezolid-Nonsusceptible Enterococcus faecalis in a Tertiary Care Hospital
Kuenyoul PARK ; Yun Sil JEONG ; Jeonghyun CHANG ; Heungsup SUNG ; Mi Na KIM
Annals of Laboratory Medicine 2020;40(4):321-325
This study investigated resistance mechanisms and epidemiology of emerging linezolid-nonsusceptible Enterococcus faecalis (LNSEF) in a tertiary care hospital. LNSEF isolated from clinical samples were collected from November 2017 to June 2019. The isolates were investigated for linezolid resistance and the associated molecular mechanisms, including mutations of 23S rRNA domain V and acquisition of the cfr or optrA resistance gene. We used pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing for the molecular typing of the isolates. Among 4,318 E. faecalis isolates, 10 (0.23%) were linezolid-nonsusceptible. All LNSEF isolates were optrA-positive and cfr-negative. Of these isolates, five were sequence type (ST) 476, two ST585, one ST16, one ST16-like, and one ST480. Six LNSEF isolates obtained in the first year clustered to three types in the PFGE analysis: two ST476 isolates of type A, two ST585 isolates of type B, and two ST16 or ST16-like isolates of type C. Seven cases were of community-onset and three were hospital acquired, but total of eight were healthcare-associated including five community-onset. None of the patients had a history of linezolid treatment, and in one patient, we detected linezolid-susceptible E. faecalis one month before LNSEF detection. In conclusion, heterogenous clones of optrA-positive LNSEF emerged in the hospital mainly via community-onset.
10.Mucinous Histology as a Predictive Marker of 5-Fluorouracil-based Adjuvant Chemotherapy for Colon Cancer.
Jeonghyun KANG ; Byung Soh MIN ; Yoon Ah PARK ; Nam Kyu KIM ; Seung Kook SOHN ; Chang Hwan CHO ; Kang Young LEE
Journal of the Korean Society of Coloproctology 2009;25(4):241-247
PURPOSE: The aim of this study was to evaluate the value of mucinous histology as a predictive marker of 5-Fluorouracil (FU)-based adjuvant chemotherapy in stage II, III colon cancer. METHODS: Between January 1995 and December 2004, 987 patients who underwent curative resections for stage II, III sporadic colon cancer were classified into two groups, a mucinous carcinoma (MC) group and a non-mucinous carcinoma (NMC) group, based on the histology of the primary tumor. The differences in their clinicopathological characteristics and the prognostic impact of 5-FU-based adjuvant chemotherapy for various tumor histologies were analyzed. RESULTS: Of the 987 patients, MCs accounted for 6.8% (68 patients). MCs were more frequently located in the Rt. Colon (P<0.001) and were more frequently seen in young patients (less than 40 yr old) (P=0.028). The 5-yr survival rates between MC and NMC did not show any statistically significant difference. Patients, including both MC and NMC patients, who received 5-FU-based chemotherapy, revealed a better overall survival rate than patients with no adjuvant chemotherapy. In the multivariate analysis for the prognosis in NMC patients, 5-FU-based adjuvant chemotherapy, initial negative nodal status, and preoperative CEA <5 ng/mL were statistically significant prognostic factors (P values: <0.001, <0.001, and <0.001, respectively). In contrast, there was no statistically independent significance of 5-FU-based adjuvant chemotherapy in MC patients. CONCLUSION: In stage II and stage III sporadic colon cancer patients, response to 5-FU-based adjuvant chemotherapy in MC patients might be poor than it is in NMC patients.
Adenocarcinoma, Mucinous
;
Chemotherapy, Adjuvant
;
Colon
;
Colonic Neoplasms
;
Fluorouracil
;
Humans
;
Mucins
;
Multivariate Analysis
;
Prognosis
;
Survival Rate