Clinical features and outcomes of JAK2V617F-positive polycythemia vera and essential thrombocythemia according to the JAK2V617F allele burden

Background@#JAK2mutation status is a well-known risk factor for thrombosis in patients with myeloproliferative neoplasms. However, the clinical usefulness of JAK2V617F allele burden is under investigation. @*Methods@#We retrospectively evaluated the impact of the JAK2V617F allele burden on clinical characteristics and outcomes of JAK2V617F-positive polycythemia vera (PV) and essential thrombocythemia (ET). The JAK2V617F allele burden was measured using sequencing. @*Results@#Altogether, 127 patients with JAK2V617F mutation (PV, N=61; ET, N=66) were included in this study. JAK2V617F allele burdens were positively correlated with white blood cell counts, hemoglobin values, lactate dehydrogenase levels, and platelet counts. The median values of JAK2V617F allele burden in patients with PV and ET were 58% and 30%, respectively. A JAK2V617F allele burden of ≥30%, older age, and a higher hemoglobin level were risk factors for thrombotic events in ET. In patients with PV, older age was the only thrombotic risk factor. The 8-year probabilities of overall survival (OS) were 82.9% in all patients. A high JAK2V617F allele burden (≥58%) was associated with poor OS in patients with PV. For the patients with ET, the difference in 8-year OS based on the JAK2V617F allele burden was not significant. @*Conclusion@#The JAK2V617F allele burden was correlated with hematologic parameters and clinical outcomes. Assessing the JAK2V617F allele burden can be helpful in predicting the thrombotic risk and disease course in patients with JAK2V617F-positive PV and ET.

Therapeutic Plasma Exchange in Patients with Severe Fever with Thrombocytopenia Syndrome: A Single Institution Experience / 대한수혈학회지

Background@#Severe fever with thrombocytopenia syndrome (SFTS) is a novel infection caused by the tick-borne SFTS virus. More than 200 patients are reported every year in Korea, but there is no established treatment. In patients with SFTS, therapeutic plasma exchange (TPE) can be applied. @*Methods@#Clinical and laboratory characteristics of patients diagnosed with SFTS who underwent TPE were analyzed. The factors that can differentiate the prognosis between the patients who recovered after TPE and those who died were analyzed. @*Results@#Ten patients were diagnosed with SFTS and treated with TPE. The mean age was 70.8 (49–85) years, with three men and seven females. The laboratory findings showed a decrease in white blood cell (WBC) count, platelet count, and serum albumin and an increase in AST, ALT, LDH, and CK levels. Patients performed an average of three (2∼4) TPE procedures at intervals of 1∼2 days, three of whom died. Compared to the results at admission, the WBC counts increased after TPE, and the platelet counts remained unchanged. The AST, LDH, and CK levels decreased by 2∼6 fold in the recovered patients and increased in those who died. Among them, the change in LDH was statistically significant between the two groups (P=0.0227). @*Conclusion@#TPE has been used as an adjuvant treatment in SFTS patients who do not have a definitive treatment to date. Additional studies, including small-scale studies such as this study, will be needed to establish the timing, interval, and predictive factors of the effect of TPE.

Therapeutic Plasma Exchange in Patients with Severe Fever with Thrombocytopenia Syndrome: A Single Institution Experience / 대한수혈학회지

Background@#Severe fever with thrombocytopenia syndrome (SFTS) is a novel infection caused by the tick-borne SFTS virus. More than 200 patients are reported every year in Korea, but there is no established treatment. In patients with SFTS, therapeutic plasma exchange (TPE) can be applied. @*Methods@#Clinical and laboratory characteristics of patients diagnosed with SFTS who underwent TPE were analyzed. The factors that can differentiate the prognosis between the patients who recovered after TPE and those who died were analyzed. @*Results@#Ten patients were diagnosed with SFTS and treated with TPE. The mean age was 70.8 (49–85) years, with three men and seven females. The laboratory findings showed a decrease in white blood cell (WBC) count, platelet count, and serum albumin and an increase in AST, ALT, LDH, and CK levels. Patients performed an average of three (2∼4) TPE procedures at intervals of 1∼2 days, three of whom died. Compared to the results at admission, the WBC counts increased after TPE, and the platelet counts remained unchanged. The AST, LDH, and CK levels decreased by 2∼6 fold in the recovered patients and increased in those who died. Among them, the change in LDH was statistically significant between the two groups (P=0.0227). @*Conclusion@#TPE has been used as an adjuvant treatment in SFTS patients who do not have a definitive treatment to date. Additional studies, including small-scale studies such as this study, will be needed to establish the timing, interval, and predictive factors of the effect of TPE.

IgG Seroprevalence of COVID-19 among Individuals without a History of the Coronavirus Disease Infection in Daegu, Korea

Background@#Seroprevalence studies of coronavirus disease 2019 (COVID-19) from many countries have shown that the number of undiagnosed missing cases is much larger than that of confirmed cases, irrespective of seroprevalence levels. Considering the strategy of Korea entailing massive testing and contact tracing from the beginning of epidemic, the number of undiagnosed missing cases in Korea may be negligible. This study was conducted to estimate the seroprevalence of COVID-19 among individuals who were never diagnosed with COVID-19 in Daegu, the epicenter of COVID-19 epidemic in Korea. @*Methods@#Serologic testing for immunoglobulin G antibody based on immunochromatographic assay was conducted in 103 patients and 95 guardians aged 18 to 82 years without any history of COVID-19 diagnosis, who visited outpatient clinics of a single university-affiliated hospital from May 25 to June 5, 2020. @*Results@#The estimated seroprevalence was 7.6% (95% confidence interval, 4.3%–12.2%) with 15 positive cases. Among them, only one had a polymerase chain reaction (PCR)-confirmed case among their close contacts and 13 did not experience COVID-19-related symptoms. Seroprevalence was similar between patients and guardians. Based on this figure, the number of undiagnosed missing cases in Daegu was estimated to be a dozen times more than the number of confirmed cases based on PCR testing. @*Conclusion@#Despite the limitation of a small and unrepresentative sample, this is the first study on seroprevalence of COVID-19 in Korea. Our study suggested that the number of undiagnosed missing cases was substantial even with the stringent strategy adopted in Korea, similar to that of other countries.

Risk Factors for Adverse Events of Therapeutic Plasma Exchange Assessed in a Single Center Study / 대한수혈학회지

BACKGROUND: Therapeutic plasma exchange (TPE) is used to remove pathologic substances involved in various disease etiologies. The use of TPE is increasing steadily in a variety of disease. This study analyzed the incidence, type and severity of adverse events (AE) according to the initial TPE of each patient in a single center. The risk factors for AE of TPE were also elucidated. METHODS: The medical and laboratory records of patients, who received TPE from January 2014 to December 2018, were reviewed retrospectively. The signs or symptoms during and after TPE were analyzed. RESULTS: TPE sessions were performed on 95 patients. The mean age was 53.3 years and men comprised 63.2%. The most common indication for TPE was desensitization for ABO-incompatible liver transplantation (ABO-i LT) (N=56, 58.9%). A total of 27 patients (28.4%) experienced AE during the initial TPE. The types of AE were allergic reactions (N=14, 14.7%), anaphylactic reaction (N=3, 11.1%), hypotension (N=5, 5.3%), hypocalcemic reaction (N=4, 4.2%), and febrile nonhemolytic reaction (N=1, 1.1%). The severities of AE were evaluated as mild in eight procedures (8.4 %), moderate in seventeen (17.9 %), and severe in two (2.1 %). Multivariable logistic regression analysis showed that the desensitization for ABO-i LT (odds ratio (OR), 2.08; 95% CI, 1.03~4.22) and the amount of FFP (OR, 1.07; 95% CI, 1.01~1.09) were associated with a higher incidence of AE. CONCLUSION: TPE can be performed under careful patient monitoring to provide prompt intervention, particularly in patients with desensitization of ABO-i LT using FFP.

Annual Report of the Korean Association of External Quality Assessment Service on Urinalysis and Fecal Occult Blood Testing (2018)

In 2018, external quality assessment trials for urinalysis and fecal occult blood (FOB) were performed using 1,590 participants. Urine chemistry tests were performed thrice while urine sediment and FOB tests twice. Urine chemistry tests comprised of pH, protein, glucose, ketone body, bilirubin, blood, urobilinogen, nitrite, leukocyte, and specific gravity analyses. The results of urine chemistry and specific gravity tests showed accuracy rates >95%, except for the pH test. The accuracy rate of urine sediments was low, especially for atypical calcium oxalate crystal and red blood cell cast. In the FOB quality test, reagents showed accuracy rates >90%, except for SD and GC Genedia FOB reagents. In the FOB quantitative test, Alfresa NS-Plus C instrument showed falsely high values in the FOB negative specimens.

Acute Monoblastic Leukemia with t(11;17)(q23;q21): Fusion of the KMT2A(MLL) and MLLT6(AF17) Genes

The KMT2A (formerly MLL) gene is associated with at least 10% of all cases of acute leukemia. More than 80 translocation partner genes of KMT2A have been discovered to date, six of which have been identified on the long arm of chromosome 17. Among these, the MLLT6 (formerly AF17) gene is located at 17q12 and fuses with the KMT2A gene in rare cases of acute leukemia. We report here a case of AML with a KMT2A/MLLT6 fusion that was confirmed using molecular genetic methods. According to a literature review, this is the first reported case of AML with a KMT2A/MLLT6 fusion in Korea.

The First Case of Otitis in Korea Caused by Brevibacterium otitidis

Brevibacterium spp. are gram-positive rods that are considered to be strictly nonpathogenic, and a very few cases of their infection in humans have been reported. In this study, we report a case of otitis caused by Brevibacterium otitidis. A 53-year-old woman, who visited the hospital, complained of symptoms, such as otorrhea from both ears, ear fullness, tinnitus, and hearing impairment, for several months. Ear discharge was cultured on blood agar for pathogen identification. Bacteria from the isolated colony were initially identified as Actinomyces odontolyticus by VITEK 2 (bioMerieux, France), whereas VITEK® MS (bioMerieux, France) identified them as Brevibacterium luteolum. Subsequently, bacteria from the isolated colony were confirmed as B. otitidis by 16S rRNA sequencing. Antimicrobial susceptibility testing confirmed their sensitivity to vancomycin and linezolid and resistance to clindamycin and penicillin. To our knowledge, this is the first reported case of otitis caused by B. otitidis in Korea.

Annual Report on the External Quality Assessment Scheme for Urinalysis and Fecal Occult Blood Testing in Korea (2017)

In 2017, external quality assessment trials for urinalysis and fecal occult blood (FOB) were performed with 1,544 participants. Urine chemistry tests were performed three times and urine sediment and FOB tests were evaluated 2 times. Urine chemistry tests consisted of pH, protein, glucose, ketone, bilirubin, blood, urobilinogen, nitrite, leukocyte, and specific gravity analyses. The results of the urine chemistry and specific gravity tests showed accuracy rates >95%. The accuracy rate of urine sediments was low, especially for fat droplets and atypical uric acid crystals. In the FOB quality test, all reagents showed accuracy rates >82%, which suggested the persistent improvement of false-positive reactions. In the FOB quantitative test, discrepant results depending on the instrument used were observed. To compensate for the result differences caused by the amounts of stool samples, the results should be reported using another unit (µg/g of stool).

Incidence of Adverse Transfusion Reactions from an Institutional Hemovigilance System: A Single Center Study / 대한수혈학회지

BACKGROUND: A hemovigilance system is essential to detect and analyze adverse transfusion reactions to various blood components. A blood bank physician has the role of discriminating the adverse transfusion reactions based on the hemovigilance criteria. This study investigated the incidence of adverse transfusion reactions per transfused case and the incidence of adverse transfusion reactions according to the various blood components in recipients. METHODS: From January 2016 to February 2017, 38,689 blood component units were transfused into 3,768 patients. A total of 11,170 transfused cases were reported. The patients’ signs or symptoms were monitored and reported by nurses using an electronic reporting system. A blood bank physician classified the adverse transfusion reactions according to the Korean hemovigilance reporting definitions. RESULTS: The frequency of all transfusion-related events was 469 according to the nursing record. Out of 469 events, 175 (37.3%) were classified as adverse transfusion reactions. The incidence of a febrile nonhemolytic transfusion reaction according to the blood component was highest for red blood cells (1.3%), followed by a platelets (0.8%) and fresh frozen plasma (0.3%). The incidence of allergic reactions was 1.0% (platelets), 0.8% (fresh frozen plasma), and 0.3% (red blood cells). The incidence of febrile nonhemolytic transfusion reactions was lowered significantly by leukocyte-reduction. CONCLUSION: The incidence of adverse transfusion reactions was 37.3% of the transfusion-related events. Therefore, close monitoring by the blood bank physician is essential for safe transfusion. The use of leukocyte-reduced blood components could reduce the incidence of febrile nonhemolytic transfusion reactions.

Annual Report on the External Quality Assessment Scheme for Urinalysis and Faecal Occult Blood Testing in Korea (2016)

In 2016, external quality assessment trials for urinalysis and faecal occult blood (FOB) were performed with 1,487 participants in Korea. Urine chemistry and FOB tests were performed three and two times, respectively, whereas urine sediment was evaluated once using photography. Urine chemistry tests consisted of pH, protein, glucose, ketone, bilirubin, blood, urobilinogen, and nitrite levels; leukocyte count; specific gravity. The results of the urine chemistry and specific gravity tests showed accuracy rates of >95%. The accuracy rate of urine sediments was low, especially that for transitional epithelial cells and atypical crystals. In the FOB quality test, all reagents showed accuracy rates of >90%, which suggested the improvement of false-positive reaction. In the FOB quantitative test, discrepant results depending on the instrument used was observed. To compensate for the result differences caused by the stool samples, the results should be reported using another unit (µg/g of stool).

Evaluation of CD3+CD4-CD8- (Double-negative) T Cells in Bronchoalveolar Lavage Fluid: an Effective Tool for Pulmonary Disease Diagnosis

BACKGROUND: Cellular analysis of bronchoalveolar lavage fluid (BALF) is a useful diagnostic tool for interstitial lung diseases (ILDs). The lymphocytes in BALF consist of CD3+CD4+ T cells (T4), CD3+CD8+ T cells (T8), and a few B cells. However, sometimes, an increased number of CD3+CD4-CD8- T cells (double-negative T cells, DNTs) are noted in BALF. It is known that DNTs in the blood are associated with immunoregulation and autoimmune diseases. However, there are only few studies on DNTs in BALF. We evaluated the DNTs in BALF in patients with pulmonary diseases. METHODS: Immunophenotyping results of the BALF obtained from 122 pulmonary disease patients over an 8-yr period were reviewed. T-lymphocyte subsets (T4, T8, and DNT) and inflammatory markers were analyzed for each group of clinical diagnosis. T-lymphocyte percentage of more than 15% of the total cells was defined as BALF lymphocytosis, and DNT percentage of more than 5% of T lymphocytes was defined as high DNT. RESULTS: The most frequent diseases found in the patients were pneumonia (31.6%), autoimmune-related ILDs (18.0%), hypersensitivity pneumonitis (10.7%), and organizing pneumonia (10.7%). However, the occurrence of autoimmune-related ILDs was significantly high (40%) in patients with lymphocytosis and high DNT (P=0.002). All lung cancer patients showed lymphocytosis with high DNT. In addition, CD3-signal intensities of DNTs were significantly higher than those of other T-lymphocyte subtypes (P=0.003). CONCLUSION: The number of DNTs in BALF was increased in patients with autoimmune-related ILDs and lung cancer. High DNTs in BALF are useful as supportive diagnostic tools for autoimmune-related ILDs.

The Relationship between ABO Blood Group Phenotypes and Seroprevalence of Infectious Disease in Korea / 대한수혈학회지

BACKGROUND: The distribution of ABO and Rhesus D (RhD) blood group antigens differs according to race and region. Previous studies have reported that blood group type was associated with not only transfusion-related diseases but also various diseases, such as malignancy and infectious disease. However, true relationship of blood groups and many diseases remained controversial. The aim of this study was to determine whether ABO and RhD blood groups are correlated with several infectious diseases. METHODS: From January 2003 to December 2012, we retrospectively reviewed results for HBsAg, HCV Ab, HIV Ab, VDRL, HAV IgM, CMV IgM, EBV VCA IgM, and Clostridium difficile toxin A and B (CD toxin). We also reviewed ABO and RhD results of these patients. Data were analyzed using chi-square test and binary logistic regression test. Odds ratio and 95% confidence intervals were determined. RESULTS: A total of 109,898 medical records of ABO and HBsAg results were reviewed. Blood group type-A was more prone to have positive results with HBsAg, while blood group type-O was less affected (odds ratio 1.086, P=0.003, odds ratio 0.935, P=0.029, respectively). With 3,171 records of CD toxin, blood group type-O was more affected (odds ratio 1.247, P=0.027). The relationship of the other serologic results and blood groups was not statistically significant. CONCLUSION: Seroprevalence of HBsAg and CD toxin showed an association with blood group type. Blood group type-A had higher HBsAg seroprevalence than the other group. Blood group type-O was more prone to have CD toxin.

Total extract of Korean red ginseng facilitates human bone marrow hematopoietic colony formation in vitro

BACKGROUND: The number of CD34+ cells in a peripheral blood stem cell collection is the key factor in predicting successful treatment of hematologic malignancies. Korean Red Ginseng (KRG) (Panax ginseng C.A. Meyer) is the most popular medicinal herb in Korea. The objective of this study was to determine the effect of KRG on hematopoietic colony formation. METHODS: Bone marrow (BM) samples were obtained from 8 human donors after acquiring informed consent. BM mononuclear cells (MNCs) were isolated, and CD34+ cells were sorted using magnetic beads. The sorted CD34+ cells were incubated with or without total extract of KRG (50 microg/mL, 100 microg/mL) or Ginsenoside Rg1 (100 microg/mL), and the hematopoietic colony assay was performed using methylcellulose semisolid medium. The CD34+ cell counts were measured by a single platform assay using flow cytometry. RESULTS: The numbers of human BM-MNCs and CD34+ cells obtained after purification were variable among donors (5.6x10(7) and 1.3-48x10(7) and 8.9x10(4) and 1.8-80x10(4), respectively). The cells expanded 1,944 times after incubation for 12 d. Total extract of KRG added to the hematopoietic stem cell (HSC)-specific medium increased CD34+ cell counts 3.6 times compared to 2.6 times when using HSC medium alone. Total numbers of hematopoietic colonies in KRG medium were more than those observed in conventional medium, especially that of erythroid colonies such as burst forming unit-erythroid. CONCLUSION: Total extract of KRG facilitated CD34+ cell expansion and hematopoietic colony formation, especially of the erythroid lineage.

Mobilization of Peripheral Blood Stem Cells for Autologous Transplantation in Patients with Hematologic Malignancies

BACKGROUND: Autologous peripheral blood-stem cell transplantation (autoPBSCT) is the treatment of choice for hematologic malignancy, because the technique requires neither general anesthesia nor surgical intervention, amongst many other advantages. Despite these benefits, the risk of hematologic malignancy, as well as the effect of patient age and sex on the prediction of successful collection of autoPBSCT are still unclear. The purpose of this study was to examine whether the hematologic diagnosis of the disease, and age or sex affect the mobilization of CD34+ cells and mononuclear cells. METHODS: We retrospectively investigated 30 (6 multiple myeloma, 11 diffuse large B-cell lymphoma, 8 acute myeloid leukemia, 2 acute lymphoid leukemia, and 3 T-cell lymphoma) patients who underwent autoPBSCT between 2008 and 2011 at Daegu Catholic University Hospital. RESULTS: Patients with multiple myeloma had the highest average of both mononuclear cell (MNC) (2.07+/-0.67x10(8) cells/kg) and CD34+ cell (1.28+/-0.58x10(6) cells/kg) counts. Patients with T-cell lymphoma had both the lowest MNC (1.23+/-0.49x10(8) cells/kg) and CD34+ cell (0.20+/-0.6x10(6) cells/kg) counts. Male patients showed greater collected CD34+ cell counts (0.96+/-1.38x10(6) cells/kg) and MNC counts (1.71+/-0.76x10(8) cells/kg) than the female patients. Patients under the age of 44 had higher collected CD34+ cell counts (0.96+/-1.37x10(6) cells/kg) but lower counts of MNC (1.49+/-0.74x10(8) cells/kg). CONCLUSIONS: The collected MNC and CD34+ cell counts varied between the types of malignancies, and with respect to sex and age. However, only collected MNC counts were significantly different (P<0.05) among the different types of malignancies.

Mean cell volumes of neutrophils and monocytes are promising markers of sepsis in elderly patients

BACKGROUND: Sepsis in elderly patients is a major cause of morbidity and mortality in the clinical setting. The aim of this study was to assess the diagnostic significance of volume conductivity scatter (VCS) parameters and to compare their reliability with that of inflammatory markers. METHODS: Patients (N=85) were divided into 3 groups according to their clinical history and culture results: control (N=29), localized infection (N=38), and sepsis (N=18). VCS parameters were obtained using a UniCel DxH 800 Coulter system. Cut-off values were established based on receiver operator characteristic (ROC) curves. RESULTS: The mean volumes of neutrophils (MNV) and monocytes (MMV) were higher in the sepsis group than in the localized infection and control groups (P=0.000 for both). The mean cell conductivity and low median angle light scatter of neutrophils were lower in the sepsis group than in the localized infection and control groups (P=0.029 and P=0.022, respectively). With a cut-off of 156.5, MNV had a sensitivity of 83.3% and a specificity of 78% in predicting sepsis. CONCLUSION: MNV and MMV, which can be obtained easily using an automated blood analyzer, may be promising hematologic parameters for distinguishing elderly individuals with and without sepsis and may help clinicians in the diagnosis of sepsis.

A case of myelodysplastic syndrome with marked eosinophilia showing favorable prognosis

Myelodysplastic syndrome (MDS) with eosinophilia is a rare condition and has yet to be classified under the 2008 World Health Organization classification. However, reports have described the prognostic significance of chronic persistent eosinophilia in MDS. Here, we report a case of a 67-year-old woman who was admitted to the hospital in July 2007 with generalized weakness, dizziness, and dyspnea on exertion persisting for 5 years. In the initial investigation, eosinophilia (22.1%) in peripheral blood and an increased proportion of eosinophils (5.6%) in normocellular bone marrow with dysplastic megakaryocytes and erythroid cells were noted. Eosinophilia was continuously detected during follow-up over 3 years. In a second bone marrow examination in August 2010, hypercellular bone marrow with similar features was observed. These findings led to the diagnosis of MDS with chronic persistent eosinophilia. To increase awareness of the prognostic significance of MDS with chronic eosinophilia, here we report a slow-progressing case of MDS with chronic persistent eosinophilia lasting over 6 years.

Comparison of Inofoam(R) and Medifoam(R) for Donor Site Dressing after Split Thickness Skin Graft in Burn Patients

PURPOSE: Inofoam(R) is a hydrocellular material developed recently for wound dressing. In the present study, the efficacy of Inofoam(R) for donor site dressing after split thickness skin graft (STSG) was evaluated and compared with that of Medifoam(R). METHODS: The study was conducted on 15 patients with third degree of burn underwent STSG from Nov. 2011 to Feb. 2012. Donor sites were divided into groups of Inofoam(R) and Medifoam(R). The duration of wound healing, pain score and exudate absorption ratio were compared between the two groups. RESULTS: The duration of wound healing time was 10.7+/-2.2 days in Inofoam(R) group, 10.5+/-2.0 days in Medifoam(R) group (P>0.05). On postoperative 1 day, the exudate absorption ratio in was 341.6+/-59.3% in Inofoam(R) group and 349.0+/-41.8% in Medifoam(R) group. There were no significant differences in wound healing duration, swelling ratio, and pain score between the two groups (P>0.05). CONCLUSION: The present study shows that the efficacy of a recently used polyurethane foam Inofoam(R) for donor site dressing is as effective as that of Medifoam(R).

Prevalence and Clinical Characteristics of Mupirocin-Resistant Staphylococcus aureus / 대한임상미생물학회지

BACKGROUND: Nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) is a known risk factor for nosocomialtransmission and infection. In an effort to mitigate this problem, topical mupirocin has been widely used for clearing nasal carriage of MRSA. However, mupirocin resistance has become a worldwide concern due to increased use of the antibiotic. The aims of this study were to evaluate the clinical characteristics and prevalence of mupirocin resistance among clinical isolates of staphylococci and to investigate antimicrobial susceptibility. METHODS: A total of 175 S. aureus specimens recovered over a 4-month period from various body sites were tested for resistance to mupirocin and other antibiotics using the Vitek2 automated system. The presence of the mupA gene was assessed in isolates exhibiting resistance to mupirocin and in other selected organisms. The clinical characteristics of the isolates were also reviewed. RESULTS: Of the 175 S. aureus isolates, 9.1% (16/175) were resistant to mupirocin, with 1.7% (3/175) having high-level resistance (HR) and 7.4% (13/175) having low-level resistance (LR). Patients with HR-mupirocin-resistant S. aureus had a longer duration of hospitalization (P=0.026). Of the 13 LR-mupirocin-resistant S. aureus strains, 11 had identical antibiogram patterns. The mupA gene was detected only among HR isolates. CONCLUSION: The rate of mupirocin resistance in the S. aureus isolates was high. The spread of mupirocin-resistant S. aureus may be due to nosocomial infection.

Comparison of Analytical Performance between the Sysmex UF-100 flow cytometer and the Iris iQ200 Urine Microscopy System / 임상검사와정도관리

BACKGROUND: The UF-100 flow cytometer (Sysmex Co., Japan) and the Iris iQ200 (Iris Diagnostics, USA) are widely used for routine urinalysis in Korea. We compared the diagnostic accuracy of these two automated systems based on the microscopic finding, and evaluated the clinical performance of the automated systems. METHODS: A total of 323 fresh urine samples were selected and analyzed by conventional microscopy and the automation systems, the UF-100 and the iQ200. Quantification for RBCs, WBCs, and bacteria were also evaluated using both automated systems. RESULTS: For 158 of urine sample classified as normal urines, the agreement rate for the UF-100 and the iQ200 was 84.8% (N=134) and 89.9% (N=142), respectively. For 165 of urine samples classified as abnormal urines, the agreement rate for the UF-100 and the iQ200 was 90.9% (N=150) and 81.8% (N=135), respectively. The UF-100 showed a good linearity in the quantitative measurements of RBCs and WBCs. For both systems, false-negative value for WBCs and bacteria were about 30% in abnormal urines. Both systems showed inaccurate results for pathologic casts and bacteria. CONCLUSIONS: We compared the microscopic finding and the primary results of automated systems without user reclassification, and the agreement rate was about 85%. The agreement rate will be improved by deliberating "Review" comments of the instruments.