Evaluation of Five Automated Urine Analyzers as Screening Instruments for Enhancing Diagnostic Efficiency in Urinary Tract Infection / 대한임상미생물학회지

Background@#Although urine culture is considered a reference standard for the diagnosis of urinary tract infection (UTI), it is time-consuming, labor-intensive, and expensive. Here, we evaluated the performance of five recent automated urine analyzers for UTI diagnosis. @*Methods@#For the 510 specimens analyzed, the criterion for ‘significant bacteriuria’ was defined as ≥ 104 CFU/mL in the inoculated plate for all specimens or ≥ 103 CFU/mL for specimens from patients using a Foley catheter or with urinary symptoms. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of UTI were analyzed using indicators individually, in different combinations, or with various cut-off values. @*Results@#Seventy-one specimens (13.9%) exhibited ‘significant bacteriuria’. In the eceiver operating characteristics curve analysis, UF-5000 (Sysmex Corp., Japan) showed the highest area under the curve values for both males and females (0.876 and 0.846, respectively). The PPVs for specimens from males with all indicators positive increased up to 100% after adjusting the cut-off values. NPVs for specimens with all indicators negative were 94.3%– 98.2% in males and 78.1%–93.8% in females after adjusting the cut-off values. @*Conclusion@#As a rapid and accurate diagnostic tool, urine sediment analyzers can be valuable for UTI diagnosis by reducing unnecessary culture and can help clinicians determine a treatment plan.

Evaluation of Five Automated Urine Analyzers as Screening Instruments for Enhancing Diagnostic Efficiency in Urinary Tract Infection / 대한임상미생물학회지

Background@#Although urine culture is considered a reference standard for the diagnosis of urinary tract infection (UTI), it is time-consuming, labor-intensive, and expensive. Here, we evaluated the performance of five recent automated urine analyzers for UTI diagnosis. @*Methods@#For the 510 specimens analyzed, the criterion for ‘significant bacteriuria’ was defined as ≥ 104 CFU/mL in the inoculated plate for all specimens or ≥ 103 CFU/mL for specimens from patients using a Foley catheter or with urinary symptoms. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of UTI were analyzed using indicators individually, in different combinations, or with various cut-off values. @*Results@#Seventy-one specimens (13.9%) exhibited ‘significant bacteriuria’. In the eceiver operating characteristics curve analysis, UF-5000 (Sysmex Corp., Japan) showed the highest area under the curve values for both males and females (0.876 and 0.846, respectively). The PPVs for specimens from males with all indicators positive increased up to 100% after adjusting the cut-off values. NPVs for specimens with all indicators negative were 94.3%– 98.2% in males and 78.1%–93.8% in females after adjusting the cut-off values. @*Conclusion@#As a rapid and accurate diagnostic tool, urine sediment analyzers can be valuable for UTI diagnosis by reducing unnecessary culture and can help clinicians determine a treatment plan.

Performance Evaluation of Body Fluid Cellular Analysis Using the Beckman Coulter UniCel DxH 800, Sysmex XN-350, and UF-5000 Automated Cellular Analyzers

BACKGROUND: Automated cellular analyzers are expected to improve the analytical performance in body fluid (BF) analysis. We evaluated the analytical performance of three automated cellular analyzers and established optimum reflex analysis guidelines. METHODS: A total of 542 BF samples (88 cerebrospinal fluid [CSF] samples and 454 non-CSF samples) were examined using manual counting and three automated cellular analyzers: UniCel DxH 800 (Beckman Coulter), XN-350 (Sysmex), and UF-5000 (Sysmex). Additionally, 2,779 BF analysis results were retrospectively reviewed. For malignant cell analysis, the receiver operating characteristic (ROC) curve was used, and the detection of high fluorescence-BF cells (HF-BFs) using the XN-350 analyzer was compared with cytology results. RESULTS: All three analyzers showed good agreement for total nucleated cell (TNC) and red blood cell (RBC) counts, except for the RBC count in CSF samples using the UniCel DxH 800. However, variable degrees of differences were observed during differential cell counting. For malignant cell analysis, the area under the curve was 0.63 for the XN-350 analyzer and 0.76 for manual counting. We established our own reflex analysis guidelines as follows: HF-BFs 83.4/100 WBCs or eosinophils >3.8% are the criteria for mandatory double check confirmation with 1,000× magnification examination. CONCLUSIONS: The three automated analyzers showed good analytical performances. Application of reflex analysis guidelines is recommended for eosinophils and HF-BFs, and manual confirmation is warranted.

Clinical Application of Overlapping Confidence Intervals for Monitoring Changes in Serial Clinical Chemistry Test Results

BACKGROUND: Interpretation of changes in serial laboratory results is necessary for both clinicians and laboratories; however, setting decision limits is not easy. Although the reference change value (RCV) has been widely used for auto-verification, it has limitations in clinical settings. We introduce the concept of overlapping confidence intervals (CIs) to determine whether the changes are statistically significant in clinical chemistry laboratory test results.METHODS: In total, 1,202,096 paired results for 33 analytes routinely tested in our clinical chemistry laboratory were analyzed. The distributions of delta% absolute values and cut-off values for certain percentiles were calculated. The CIs for each analyte were set based on biological variation, and data were analyzed at various confidence levels. Additionally, we analyzed the data using RCVs and compared their clinical utility.RESULTS: Most analytes had low indexes of individuality with large inter-individual variability. The 97.5th percentile cut-offs for each analyte were much larger than conventional RCVs. The percentages of results exceeding RCV(95%) and RCV(99%) corresponded to those with no overlap at the 83.4% and 93.2% confidence levels, respectively.CONCLUSIONS: The use of overlapping CIs in serial clinical chemistry test results can overcome the limitations of existing RCVs and replace them, especially for analytes with large intra-individual variation.

Evaluation of the Analytical Performance of Atellica CH 930 Automated Chemistry Analyzer

BACKGROUND: Recently, a new automated chemistry analyzer, Atellica CH930 (Siemens, Germany), was introduced. It automatically measures internal quality control (QC) materials according to a pre-determined schedule. For this purpose, the instrument has space for storage of QC materials. We evaluated the analytical performance of chemistry items by using the Atellica system. METHODS: The precision of 29 items was evaluated with three levels of QC materials with two storage methods. We stored the QC materials in the dedicated storage space in the instrument during the precision evaluation period. In addition, we aliquoted and stored the materials in the refrigerator, and then loaded the material in a timely manner. Linearity, carry-over, and agreement with current methods were also evaluated. RESULTS: The within-laboratory coefficient of variation (CV) of most items, except for total CO2 (tCO2), was within 5.0% in both QC storage methods without significant differences in CV between storage methods. The CV of tCO2 was 5.2%, 5.8%, and 5.1% at three different levels when the QC materials were stored in a dedicated space in the instrument. The linearity was acceptable, showing <5% nonlinearity. Although good agreement was observed for most items, some items, such as calcium, total bilirubin, aspartate transaminase, and chloride, showed unequivalent results. CONCLUSIONS: Atellica CH930 showed acceptable precision, linearity, and agreement in routine chemistry items. The automatic QC function using the storage device has no problem with stability or precision. It can reduce the manual process, allowing technicians to focus on reviewing the QC results and reporting reliable results.

Evaluation of Noninvasive Liver Fibrosis Blood Markers in Patients with Chronic Hepatitis B and Hepatitis C

BACKGROUND: Liver fibrosis evaluation is an important issue in chronic liver disease patients. We aimed to develop noninvasive liver fibrosis biomarkers based on transient elastography (TE, FibroScan®) through retrospective review of clinicopathological data. METHODS: We recruited 278 chronic hepatitis B patients who underwent Fibroscan and HBV DNA testing. A total of 115 HBeAg-positive and 159 HBeAg-negative chronic hepatitis B patients were analyzed. A total of 100 hepatitis C patients were analyzed. Successful fibroscan data, gamma-glutamyl transferase (GGT) to platelet ratio (GPR), platelet count, AST, ALT, international normalized ratio of prothrombin time, total cholesterol, triglycerides, bilirubin, mean platelet volume, AST to platelet ratio index, fibrosis index based on four factors (FIB-4), neutrophil to lymphocyte ratio (NLR), and NLR to platelet ratio were analyzed to determine the new noninvasive markers for assessing liver fibrosis. RESULTS: Elevated GPR (OR=9.1, P=0.011) and FIB-4 (OR=2.3, P=0.01) were associated with greater risk of liver fibrosis in chronic hepatitis B patients. FIB-4 (OR=6.04, P=0.005) was a risk factor for liver fibrosis in HBeAg-positive patients. FIB-4 (OR=2.371, P=0.015) and GPR (OR=33.78, P=0.003) were liver fibrosis risk factor in HBeAg-negative patients. In chronic hepatitis C patients, GGT (OR=1.033, P=0.002), triglyceride (OR=−0.990, P=0.038) and FIB-4 (OR=3.499, P=0.006) showed statistical significances. The AUCs were 0.816 in FIB-4 (P<0.001) and 0.849 in GPR (P<0.001). CONCLUSIONS: FIB-4 and GPR may be useful blood markers for assessing liver fibrosis in chronic hepatitis B and hepatitis C patients. Further well-designed prospective study is required to validate these noninvasive blood markers in clinical practice.

Massilia varians Isolated from a Clinical Specimen

We report a case of Massilia varians isolated from a deep finger wound following orthopedic surgery on an immunocompetent patient. The bacterium was identified by 16S rDNA sequence analysis. This is the first case of M. varians isolated from a clinical specimen since the first report in 2008.

Evaluation of the Level of Minimum Hemoglobin Trigger for Red Blood Cell Transfusion according to Clinical Departments / 대한수혈학회지

BACKGROUND: Red blood cell (RBC) transfusion is one of the major treatments for correcting anemia, but its use should be carefully considered because of adverse transfusion reactions and inappropriate usage. Therefore, individual health care facilities have self evaluated their use of transfusion in an attempt to decrease unnecessary procedures. In this study, we evaluated the differences in the minimum hemoglobin (Hb) trigger for RBC transfusion among clinical departments in Severance Hospital. METHODS: We analyzed the electronic medical records of RBC transfusion episodes that were conducted at a Hb level above 8 g/dL from July 2014 to September 2015. We classified these data by clinical department, and considered the overall medical conditions of the patients. The minimum Hb trigger level in this study was defined as the lowest Hb level within 24 hours prior to RBC transfusion. RESULTS: A total of 4,953 RBC transfusion episodes that were conducted at Hb levels above 8 g/dL were analyzed over that period. In general, the minimum Hb trigger level was higher in the operation group than the hemorrhage group. When compared among clinical departments, the department of orthopedic surgery, neurosurgery, rehabilitation medicine, and anesthesiology showed high levels of minimum Hb trigger equal to or greater than 10 g/dL. CONCLUSION: The minimum Hb trigger level differed among clinical departments, with the operation group showing a much higher level of minimum Hb trigger. We hope that these data will be practically applied to establish plans and strategies for managing the appropriateness of RBC transfusions in Korea. In addition, continuous evaluation and transfusion education for clinical departments should be performed.

Frequency and Pattern of Noninfectious Adverse Transfusion Reactions at a Tertiary Care Hospital in Korea

BACKGROUND: Although transfusion is a paramount life-saving therapy, there are multiple potential significant risks. Therefore, all adverse transfusion reaction (ATR) episodes require close monitoring. Using the computerized reporting system, we assessed the frequency and pattern of non-infectious ATRs. METHODS: We analyzed two-year transfusion data from electronic medical records retrospectively. From March 2013 to February 2015, 364,569 units of blood were transfused. Of them, 334,582 (91.8%) records were identified from electronic nursing records. For the confirmation of ATRs by blood bank physicians, patients' electronic medical records were further evaluated. RESULTS: According to the nursing records, the frequency of all possible transfusion-related events was 3.1%. After the blood bank physicians' review, the frequency was found to be 1.2%. The overall frequency of febrile non-hemolytic transfusion reactions (FNHTRs) to red blood cells (RBCs), platelet (PLT) components, and fresh frozen plasmas (FFPs) were 0.9%, 0.3%, and 0.2%, respectively, and allergic reactions represented 0.3% (RBCs), 0.9% (PLTs), and 0.9% (FFPs), respectively. The pre-storage leukocyte reduction significantly decreased the frequency of FNHTRs during the transfusion of RBCs (P<0.01) or PLTs (Pfalling dots0.01). CONCLUSIONS: The frequency of FNHTRs, allergic reactions, and "no reactions" were 22.0%, 17.0%, and 60.7%, respectively. Leukocyte-reduction was associated with a lower rate of FNHTRs, but not with that of allergic reactions. The development of an effective electronic reporting system of ATRs is important in quantifying transfusion-related adverse events. This type of reporting system can also accurately identify the underlying problems and risk factors to further the quality of transfusion care for patients.

A Case of Panagglutination on Antibody Identification in a Multiple Myeloma Patient Receiving Daratumumab / 대한수혈학회지

Herein, we report a patient showing panagglutination in the unexpected antibody identification test after the administration of daratumumab. The patient was a 66-year-old woman who had undergone multiple cycles of chemotherapy and autologous peripheral blood stem cell transplantation for treating multiple myeloma; however, despite treatment, she had relapsed. Therefore, daratumumab, on clinical trials in Korea, started to be administered. After administration of daratumumab, the result of antibody screening test was positive, on the contrary to the result prior to the administration. Moreover, all positive reactions were shown in the antibody identification to the panel cells. After destroying CD38 antigens on the surface of RBCs using DTT, negative results were obtained. Daratumumab—a novel therapeutic human CD38 monoclonal antibody that can be used as targeted immunotherapy—is an FDA-approved drug for treating multiple myeloma. Because CD38 is expressed not only on myeloma cells, but also on red blood cells (RBCs), the use of daratumumab might lead to RBC agglutinations, and thereby resulting in false-positive results on the pre-transfusion tests. Therefore, caution is needed in case of a patient receiving daratumumab. Furthermore, additional test using DTT is required, especially when panagglutination was shown in the antibody identification test, as in this case.

Influence of Vitamin C and Maltose on the Accuracy of Three Models of Glucose Meters

No abstract available.