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Background@#This study aimed to determine the parameters for worsening oxygenation in non-severe coronavirus disease 2019 (COVID-19) pneumonia. @*Methods@#This retrospective cohort study included cases of confirmed COVID-19 pneumonia in a public hospital in South Korea. The worsening oxygenation group was defined as that with SpO2 ≤94% or received oxygen or mechanical ventilation (MV) throughout the clinical course versus the non-worsening oxygenation group that did not experience any respiratory event. Parameters were compared, and the extent of viral pneumonia from an initial chest computed tomography (CT) was calculated using artificial intelligence (AI) and measured visually by a radiologist. @*Results@#We included 136 patients, with 32 (23.5%) patients in the worsening oxygenation group; of whom, two needed MV and one died. Initial vital signs and duration of symptoms showed no difference between the two groups; however, univariate logistic regression analysis revealed that a variety of parameters on admission were associated with an increased risk of a desaturation event. A subset of patients was studied to eliminate potential bias, that ferritin ≥280 μg/L (p=0.029), lactate dehydrogenase ≥240 U/L (p=0.029), pneumonia volume (p=0.021), and extent (p=0.030) by AI, and visual severity scores (p=0.042) were the predictive parameters for worsening oxygenation in a sex-, age-, and comorbid illness-matched case-control study using propensity score (n=52). @*Conclusion@#Our study suggests that initial CT evaluated by AI or visual severity scoring as well as serum markers of inflammation on admission are significantly associated with worsening oxygenation in this COVID-19 pneumonia cohort.
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Purpose@#To retrospectively evaluate the chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) in patients with mild clinical symptoms at a single hospital in South Korea. @*Materials and Methods@#CT scans of 87 COVID-19 patients [43 men and 44 women; median age:41 years (interquartile range: 26.1–51.0 years)] with mild clinical symptoms (fever < 38℃ and no dyspnea) were evaluated. @*Results@#CT findings were normal in 39 (44.8%) and abnormal in 48 (55.2%) patients. Among the 48 patients with lung opacities, 17 (35.4%) had unilateral disease and 31 (64.6%) had bilateral disease. One (2.1%) patient showed subpleural distribution, 9 (18.8%) showed peribronchovascular distribution, and 38 (79.2%) showed subpleural and peribronchovascular distributions.Twenty-two (45.8%) patients had pure ground-glass opacities (GGOs) with no consolidation, 17 (35.4%) had mixed opacities dominated by GGOs, and 9 (18.8%) had mixed opacities dominated by consolidation. No patients demonstrated consolidation without GGOs. @*Conclusion@#The most common CT finding of COVID-19 in patients with mild clinical symptoms was bilateral multiple GGO-dominant lesions with subpleural and peribronchovascular distribution and lower lung predilection. The initial chest CT of almost half of COVID-19 patients with mild clinical symptoms showed no lung parenchymal lesions. Compared to relatively severe cases, mild cases were more likely to manifest as unilateral disease with pure GGOs or GGOdominant mixed opacities and less likely to show air bronchogram.
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Background@#In this study, we aim to examine the effects of pre-analytical factors such as specimen type (serum or plasma), collection and storage conditions, and time, on the results of chemiluminescence immunoassay. @*Methods@#Blood samples were collected from 10 individuals and aliquoted into two sets of K3-ethylenediaminetetraacetic acid (EDTA) and serumseparating tubes (SST) each, for plasma and serum collection, respectively.For all the samples, one set of tubes was centrifuged within 1 hour and other set was centrifuged after 4 hours, followed by cell separation.Chemiluminescence assay was performed for adrenocorticotropic hormone (ACTH), parathyroid hormone (PTH), osteocalcin, C-telopeptide, and insulin at 0, 6, 24, and 48 hours after centrifugation; all the samples were assayed in duplicate. The samples were stored at 4℃ before the assay. @*Results@#The results obtained showed that the levels detected in plasmas were more consistent and stable as compared to serum. After a 6-hour storage at 4℃, a significant decrease was observed in the levels of ACTH and osteocalcin in plasma and serum; whereas, PTH and C-telopeptide levels were stable in plasma but decreased significantly in serum. Insulin levels in serum showed a decrease after a 6-hour storage while the levels in plasma were found to be stable until 24-hour storage. Serum samples separated after 4 hours showed a significant decrease in all hormone levels, while C-telopeptide and insulin levels were stable in plasma samples separated after 4 hours. @*Conclusions@#The results were found to be more stable in plasma samples from K3-EDTA tubes as compared to serum samples from SST in the measurement of unstable biological analytes. These results suggest that K3-EDTA tubes are preferable in the specimen collection for assaying biological analytes.
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Background@#Two methods of counting cells in body fluids were compared;manual counting using a Neubauer chamber, and automated cell countingusing an XN-350 hematology analyzer. @*Methods@#Cells from 32 body fluid samples were counted by manualexamination and by an automated analyzer. Total cells (TC), white bloodcells (WBC), red blood cells (RBC), polymorphonuclear leukocytes (PMN),mononuclear leukocytes (MN), neutrophils, lymphocytes, monocytes, andeosinophils were each counted by both methods. The results were comparedusing the Pearson correlation test, Bland-Altman regression analysis, andPassing-Bablok regression analysis. @*Results@#The two methods showed very strong correlation in TC, WBC,RBC, PMN, and MN counts, strong correlation in % neutrophils, and %lymphocytes, and weak correlation in % monocytes and % eosinophils.Using Bland-Altman regression analysis, the mean biases for TC, WBC, andRBC were -270, -257.4, and -1,256.09, respectively, and 0.15 for PMN andMN. Research parameters were compared as well: mean biases were -1.31,-2.46, -5.16, and -3.58 for % neutrophils, % monocytes, % lymphocytes,and % eosinophils, respectively. Passing-Bablok regression equationswere y=1.039x+20, y=1.037x+19, y=1.259x+0.0, y=0.983x+1.541, andy=0.983x+0.125 for TC, WBC, RBC, PMN, and MN, respectively. The equationswere y=0.955x+2.194 for % neutrophils, y=0.965x+1.184 for % monocytes,y=1.003x+0.161 for % lymphocytes, and y=x+0.75 for % eosinophils. @*Conclusions@#WBC differential count results performed by an automatedhematology analyzer generally show good correlation with our referencemethod, Neubauer chamber counting.
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Two trials involving proficiency tests for complete blood counts (CBCs) and blood cell morphology were conducted as part of the 2019 Routine Hematology Program of the Korean Association of External Quality Assessment Service. Three different control samples were subjected to CBC testing, and two blood cell morphology images were posted on the laboratory’s website during each trial. The mean response rates of the 1,791 participating laboratories were 97.2% and 34.9% for CBC and blood cell morphology, respectively. The distribution of equipment for CBC testing was comparable to that in 2018. The coefficient of variation (CV) ranges were 2.9%–4.1%, 1.6%–2.4%, 1.4%–2.8%, 4.7%–5.3%, and 4.8%–7.3% for white blood cell counts, red blood cell counts, hemoglobin, hematocrit, and platelet counts, respectively. The concordance rate ranged from 83.5% to 99.7% in the blood cell morphology tests. In 2019, the number of participating laboratories was higher than that in 2018, and the CVs of CBC results were similar to those in 2018.
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In view of this pandemic, as of February 2020, South Korea has the second highest number of confirmed cases in the world. Herein, we report four confirmed coronavirus disease 2019 (COVID-19) cases in the early stage of the pandemic in South Korea and describe the identification, diagnosis, clinical course, and management, including one patient’s initial mild symptoms at presentation and their progression to pneumonia on day 21 of illness. Within 48 hours of hospitalization, all four patients underwent evaluation for initial laboratory parameters, COVID-19 polymerase chain reaction (PCR), and chest computed tomography (CT) findings. All four mild COVID-19 patients were discharged, and they were re-examined 14 days after discharge. Despite all four of them being asymptomatic, one patient was re-admitted after confirmation of COVID-19 through PCR viral nucleic acid detection. She could be discharged after 7 days with two subsequent negative COVID-19 PCR at 24-hour intervals. Patients with mild COVID-19 generally have normal follow-up chest CT scans after discharge, even if the early chest CT definitely indicates pneumonia. Re-hospitalized patients with COVID-19 PCR positive results after discharge were not related to her initial chest CT, lab, symptoms compared other three patients.
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Background@#The Korean Society of Thoracic Radiology (KSTR) recently constructed a nation-wide coronavirus disease 2019 (COVID-19) database and imaging repository, referred to the Korean imaging cohort of COVID-19 (KICC-19) based on the collaborative efforts of its members. The purpose of this study was to provide a summary of the clinico-epidemiological data and imaging data of the KICC-19. @*Methods@#The KSTR members at 17 COVID-19 referral centers retrospectively collected imaging data and clinical information of consecutive patients with reverse transcription polymerase chain reaction-proven COVID-19 in respiratory specimens from February 2020 through May 2020 who underwent diagnostic chest computed tomography (CT) or radiograph in each participating hospital. @*Results@#The cohort consisted of 239 men and 283 women (mean age, 52.3 years; age range, 11–97 years). Of the 522 subjects, 201 (38.5%) had an underlying disease. The most common symptoms were fever (n = 292) and cough (n = 245). The 151 patients (28.9%) had lymphocytopenia, 86 had (16.5%) thrombocytopenia, and 227 patients (43.5%) had an elevated CRP at admission. The 121 (23.4%) needed nasal oxygen therapy or mechanical ventilation (n = 38; 7.3%), and 49 patients (9.4%) were admitted to an intensive care unit.Although most patients had cured, 21 patients (4.0%) died. The 465 (89.1%) subjects underwent a low to standard-dose chest CT scan at least once during hospitalization, resulting in a total of 658 CT scans. The 497 subjects (95.2%) underwent chest radiography at least once during hospitalization, which resulted in a total of 1,475 chest radiographs. @*Conclusion@#The KICC-19 was successfully established and comprised of 658 CT scans and 1,475 chest radiographs of 522 hospitalized Korean COVID-19 patients. The KICC-19 will provide a more comprehensive understanding of the clinical, epidemiological, and radiologic characteristics of patients with COVID-19.
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Background@#Carbapenem-resistant Acinetobacter baumannii (CRAB) has emerged as an important nosocomial pathogen.The purpose of this study was to determine the effective methods for performing surveillance cultures of CRAB. @*Methods@#Nasal and rectal swabs were obtained concurrently from hospitalized intensive care unit patients colonized with CRAB. All the samples were inoculated in CHROMagar Acinetobacter medium with CR102 (CHROMagar), MacConkey agar medium supplemented with 5 µg/mL imipenem (MCA-IPM), and triptic soy broth medium supplemented with 5 µg/ mL imipenem (TSB-IPM). CRAB detection rates for each sample were compared. @*Results@#The CRAB detection rate in either one of the nasal or rectal swabs from the 37 patients tested were 89.2% (33/37) with the use of CHROMagar, 78.4% (29/37) with the use of MCA-IMP, and 86.5% (32/37) with the use of TSB-IMP. @*Conclusion@#We determined that concurrent use of both nasal and rectal swabs and CHROMagar could be an effective method for CRAB surveillance cultures.
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OBJECTIVE: This study presents a preliminary report on the chest radiographic and computed tomography (CT) findings of the 2019 novel coronavirus disease (COVID-19) pneumonia in Korea.MATERIALS AND METHODS: As part of a multi-institutional collaboration coordinated by the Korean Society of Thoracic Radiology, we collected nine patients with COVID-19 infections who had undergone chest radiography and CT scans. We analyzed the radiographic and CT findings of COVID-19 pneumonia at baseline. Fisher's exact test was used to compare CT findings depending on the shape of pulmonary lesions.RESULTS: Three of the nine patients (33.3%) had parenchymal abnormalities detected by chest radiography, and most of the abnormalities were peripheral consolidations. Chest CT images showed bilateral involvement in eight of the nine patients, and a unilobar reversed halo sign in the other patient. In total, 77 pulmonary lesions were found, including patchy lesions (39%), large confluent lesions (13%), and small nodular lesions (48%). The peripheral and posterior lung fields were involved in 78% and 67% of the lesions, respectively. The lesions were typically ill-defined and were composed of mixed ground-glass opacities and consolidation or pure ground-glass opacities. Patchy to confluent lesions were primarily distributed in the lower lobes (p = 0.040) and along the pleura (p < 0.001), whereas nodular lesions were primarily distributed along the bronchovascular bundles (p = 0.006).CONCLUSION: COVID-19 pneumonia in Korea primarily manifested as pure to mixed ground-glass opacities with a patchy to confluent or nodular shape in the bilateral peripheral posterior lungs. A considerable proportion of patients with COVID-19 pneumonia had normal chest radiographs.
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OBJECTIVE: This study presents a preliminary report on the chest radiographic and computed tomography (CT) findings of the 2019 novel coronavirus disease (COVID-19) pneumonia in Korea.MATERIALS AND METHODS: As part of a multi-institutional collaboration coordinated by the Korean Society of Thoracic Radiology, we collected nine patients with COVID-19 infections who had undergone chest radiography and CT scans. We analyzed the radiographic and CT findings of COVID-19 pneumonia at baseline. Fisher's exact test was used to compare CT findings depending on the shape of pulmonary lesions.RESULTS: Three of the nine patients (33.3%) had parenchymal abnormalities detected by chest radiography, and most of the abnormalities were peripheral consolidations. Chest CT images showed bilateral involvement in eight of the nine patients, and a unilobar reversed halo sign in the other patient. In total, 77 pulmonary lesions were found, including patchy lesions (39%), large confluent lesions (13%), and small nodular lesions (48%). The peripheral and posterior lung fields were involved in 78% and 67% of the lesions, respectively. The lesions were typically ill-defined and were composed of mixed ground-glass opacities and consolidation or pure ground-glass opacities. Patchy to confluent lesions were primarily distributed in the lower lobes (p = 0.040) and along the pleura (p < 0.001), whereas nodular lesions were primarily distributed along the bronchovascular bundles (p = 0.006).CONCLUSION: COVID-19 pneumonia in Korea primarily manifested as pure to mixed ground-glass opacities with a patchy to confluent or nodular shape in the bilateral peripheral posterior lungs. A considerable proportion of patients with COVID-19 pneumonia had normal chest radiographs.
Subject(s)
Humans , Cooperative Behavior , Coronavirus , Korea , Lung , Pleura , Pneumonia , Radiography , Radiography, Thoracic , Thorax , Tomography, X-Ray ComputedABSTRACT
Genetic hemoglobin disorders are caused by mutations and/or deletions in the α-globin or β-globin genes. Thalassemia is caused by quantitative defects and hemoglobinopathies by structural defect of hemoglobin. The incidence of thalassemia and hemoglobinopathy is increased in Korea with rapid influx of people from endemic areas. Thus, the awareness of the disease is needed. α-thalassemias are caused by deletions in α-globin gene, while β-thalassemias are associated with decreased synthesis of β-globin due to β-globin gene mutations. Hemoglobinopathies involve structural defects in hemoglobin due to altered amino acid sequence in the α- or β-globin chains. When the patient is suspected with thalassemia/hemoglobinopathy from abnormal complete blood count findings and/or family history, the next step is detecting hemoglobin abnormality using electrophoresis methods including high performance liquid chromatography and mass spectrometry. The development of novel molecular genetic technologies, such as massively parallel sequencing, facilitates a more precise molecular diagnosis of thalassemia/hemoglobinopathy. Moreover, prenatal diagnosis using genetic testing enables the prevention of thalassemia birth and pregnancy complications. We aimed to review the spectrum and classification of thalassemia/hemoglobinopathy diseases and the diagnostic strategies including screening tests, molecular genetic tests, and prenatal diagnosis.
Subject(s)
Humans , Amino Acid Sequence , Anemia , Blood Cell Count , Chromatography, Liquid , Classification , Clinical Laboratory Techniques , Diagnosis , Electrophoresis , Erythrocytes , Genetic Testing , Hematology , Hemoglobinopathies , High-Throughput Nucleotide Sequencing , Incidence , Korea , Mass Screening , Mass Spectrometry , Molecular Biology , Parturition , Pregnancy Complications , Prenatal Diagnosis , ThalassemiaABSTRACT
Two trials were conducted with proficiency tests for complete blood cell count (CBC) and blood cell morphology as part of the 2018 Routine Hematology Program of the Korean Association of External Quality Assessment Service. Three different control samples were sent for CBC testing and two blood cell morphology pictures were posted on the laboratory website during each trial. The mean response rates of the 1,719 participating laboratories were 97.4% and 37.2% for CBC and blood cell morphology, respectively. The distribution of equipment for CBC testing was comparable to that of the previous year. The coefficient of variation (CV) ranges were determined as 3.5%–4.1%, 1.9%–2.7%, 1.4%–2.8%, 4.5%–5.3%, and 5.4%–6.9% for white blood cell counts, red blood cell counts, hemoglobin, hematocrit, and platelet counts, respectively. The concordance rate ranged from 83.0% to 97.5% in blood cell morphology tests. We observed a continuous increase in the number of participating laboratories and a trend towards a decrease in the CVs of platelet counts compared to those in 2016. Values of the other assessed parameters were similar to those of the previous year.
Subject(s)
Blood Cell Count , Blood Cells , Erythrocyte Count , Hematocrit , Hematology , Laboratory Proficiency Testing , Leukocyte Count , Platelet CountABSTRACT
Viral respiratory infections are one of the most common infections worldwide. It is important to detect the virus early and precisely. In this study, we evaluated the limit of detection (LoD) and usefulness of the Real-Q RV Detection kit (BioSewoom, Seoul, Korea). We measured the LoD of the Real-Q RV Detection kit using 10 strains of standard viruses. We then compared the detection results by the Allplex Respiratory Panel Assay kit (Seegene, Seoul, Korea) using 123 clinical specimens. The discrepant results were confirmed by sequencing. Among the 10 standard viruses, the LoD of human rhinovirus (HRV) was the lowest and that of parainfluenza virus 2 and 3 was relatively high as detected by Real-Q RV Detection kit. Agreements of the two kits ranged from 95.9% to 100%. Three specimens detected negative by the Allplex Respiratory Panel kit were detected as adenovirus (AdV) by the Real-Q RV Detection kit and were confirmed by sequencing. Similarly, a specimen detected negative by the Allplex Respiratory Panel kit was detected as HRV by the Real-Q RV Detection kit and was confirmed by sequencing. A specimen detected as human enterovirus by the Allplex Respiratory Panel kit was detected as HRV by the Real-Q RV Detection kit and was confirmed by sequencing. Real-Q RV Detection kit showed good diagnostic performance and can be useful for detecting major viruses that cause respiratory infections.
Subject(s)
Humans , Adenoviridae , Enterovirus , Limit of Detection , Paramyxoviridae Infections , Respiratory Tract Infections , Rhinovirus , SeoulABSTRACT
Under the Routine Hematology Program of the Korean Association of External Quality Assessment Service, complete blood count (CBC) and blood cell morphology proficiency tests were performed during 2017. We conducted two trials, sent three control materials for CBC testing, and posted two cell morphology pictures on the website for each trial. Of 1,646 laboratories, the mean response rates for CBC and blood cell morphology were 96.7% and 42.0%, respectively. The distribution of equipment for CBC testing was similar to that of the previous year. The coefficient of variations for white blood cell counts, red blood cell counts, hemoglobin, hematocrit, and platelet counts were 3.7%–4.7%, 2.2%–2.4%, 1.5%–3.0%, 5.4%–6.0%, and 7.2%–10.2%, respectively. More than 80% of the blood cell morphology tests were concordant among all of the trials, except for the HHI-17-03 trial. In 2017, the number of participating laboratories increased, and the performance was similar to that of the previous year.
Subject(s)
Blood Cell Count , Blood Cells , Erythrocyte Count , Hematocrit , Hematology , Korea , Laboratory Proficiency Testing , Leukocyte Count , Platelet CountABSTRACT
BACKGROUND: Different age groups may have different reference intervals. However, the currently used reference interval for complete blood count (CBC) in clinical laboratories is based on results from healthy adults between 20 and 50 years of age. In this study, we aimed to establish reference intervals for 16 CBC parameters in Korean healthy elderly individuals. METHODS: A total of 3,359 healthy adults were selected from 4,253 adults (aged ≥20 years) who underwent regular health check-ups, based on a medical examination by interview. The reference intervals for CBC in two groups (aged <60 and ≥60 years), and the partitioning of reference intervals between the two age groups were established. RESULTS: Most CBC parameters showed no significant differences in reference intervals between the two age groups. Among the men, platelet distribution width (PDW) was the only parameter that required a separate reference interval between the two age groups. Among the women, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), red cell distribution width (RDW), and eosinophil % required separate reference intervals between the two age groups. CONCLUSIONS: The reference intervals for most CBC parameters were not significantly different between the two age groups. Except for PDW in men and MCV, MCHC, RDW, and eosinophil % in women, reference intervals for CBC parameters in individuals younger than 60 years of age could also be applied to those that are 60 years of age or older.
Subject(s)
Adult , Aged , Female , Humans , Male , Blood Cell Count , Blood Cells , Blood Platelets , Eosinophils , Erythrocyte IndicesABSTRACT
Platelet distribution width (PDW) is an index for platelet size variation. In this study, we analysed the correlation between PDW values obtained using two different hematology analysers that employ different measurement methods. Complete blood cell parameters including PDW for 153 healthy individuals were measured using both, ADVIA 2120i (Simens AG, Germany) and XN-3000 (Sysmex, Japan). The PDW values measured using the two hematology analysers showed a moderate correlation (r=0.661, P0.900, P<0.001). PDW obtained using XN-3000 showed a strong correlation with mean platelet volume, whereas PDW obtained using ADVIA 2120i did not. The reference values in this group were 40.0%–64.2% in ADVIA 2120i and 9.0–16.0 fL in XN-3000. In conclusion, PDW values obtained using ADVIA 2120i and XN-3000 are not interchangeable. In laboratories equipped with more than one hematology analyser, a particular analyser should be used consistently for monitoring a particular patient.
Subject(s)
Humans , Blood Cells , Blood Platelets , Erythrocyte Indices , Erythrocytes , Hematology , Leukocytes , Mean Platelet Volume , Platelet Count , Reference ValuesABSTRACT
Under the Routine Hematology Program of Korean Association of External Quality Assessment Service, proficiency tests for complete blood count (CBC) and blood cell morphology were performed during 2016. We conducted two trials, and sent three level control materials for CBC testing and posted two cell morphology pictures on the website for each trial. Of 1,455 laboratories, the mean response rates for CBC and blood cell morphology were 96.3% and 40.4%, respectively. The distribution of equipment for CBC test was similar to that of previous year. The coefficient of variations for white blood cell counts, red blood cell counts, hemoglobin, hematocrit, and platelet counts, were 3.8%–4.5%, 1.9%–2.3%, 1.4%–2.8%, 4.8%–5.8%, and 6.2%–9.4%, respectively. More than 80% of the blood cell morphology tests were concordant in all trials. In 2016, the number of participating laboratories increased, and the performance was similar to that of the previous year.
Subject(s)
Blood Cell Count , Blood Cells , Erythrocyte Count , Hematocrit , Hematology , Korea , Laboratory Proficiency Testing , Leukocyte Count , Platelet CountABSTRACT
The standardization committee of the Korean Society for Laboratory Hematology sought to establish standardized testing guidelines for the diagnosis of hematologic malignancies. The guidelines were developed on the basis of survey results and international guidelines, including the National Comprehensive Cancer Network Guidelines and European LeukemiaNet recommendations. The committee expects that the diagnostic guidelines presented here will enhance diagnostic test standardization and clinical decision making and that the novel developments due to new molecular technologies will be integrated into the diagnostic algorithms through ongoing consensus initiatives.