Performance evaluation of newly developed fluorescence immunoassay-based interferon-gamma release assay for the diagnosis of latent tuberculosis infection in healthcare workers

The ichroma™ IGRA-TB (Boditech Med Inc., Chuncheon, Republic of Korea) is an automated fluorescent immunoassay-based point-of-care interferon-gamma release assay for detecting latent tuberculosis infection. We evaluated this assay with 408 health care workers, and demonstrated its acceptable performances comparing to QuantiFERON-TB Gold-Plus (QFT-Plus; Qiagen, Germantown, MD).

Convolutional Neural Network to Stratify the Malignancy Risk of Thyroid Nodules: Diagnostic Performance Compared with the American College of Radiology Thyroid Imaging Reporting and Data System Implemented by Experienced Radiologists

BACKGROUND AND PURPOSE

Comparison of the diagnostic performance for thyroid cancer on ultrasound between a convolutional neural network and visual assessment by radiologists has been inconsistent. Thus, we aimed to evaluate the diagnostic performance of the convolutional neural network compared with the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) for the diagnosis of thyroid cancer using ultrasound images.

MATERIALS AND METHODS

From March 2019 to September 2019, seven hundred sixty thyroid nodules (≥10 mm) in 757 patients were diagnosed as benign or malignant through fine-needle aspiration, core needle biopsy, or an operation. Experienced radiologists assessed the sonographic descriptors of the nodules, and 1 of 5 American College of Radiology TI-RADS categories was assigned. The convolutional neural network provided malignancy risk percentages for nodules based on sonographic images. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated with cutoff values using the Youden index and compared between the convolutional neural network and the American College of Radiology TI-RADS. Areas under the receiver operating characteristic curve were also compared.

RESULTS

Of 760 nodules, 176 (23.2%) were malignant. At an optimal threshold derived from the Youden index, sensitivity and negative predictive values were higher with the convolutional neural network than with the American College of Radiology TI-RADS (81.8% versus 73.9%, P = .009; 94.0% versus 92.2%, P = .046). Specificity, accuracy, and positive predictive values were lower with the convolutional neural network than with the American College of Radiology TI-RADS (86.1% versus 93.7%, P < .001; 85.1% versus 89.1%, P = .003; and 64.0% versus 77.8%, P < .001). The area under the curve of the convolutional neural network was higher than that of the American College of Radiology TI-RADS (0.917 versus 0.891, P = .017).

CONCLUSIONS

The convolutional neural network provided diagnostic performance comparable with that of the American College of Radiology TI-RADS categories assigned by experienced radiologists.

Blood Amyloid-β Oligomerization as a Biomarker of Alzheimer's Disease: A Blinded Validation Study

BACKGROUND

Oligomeric amyloid-β (Aβ) is one of the major contributors to the pathomechanism of Alzheimer's disease (AD); Aβ oligomerization in plasma can be measured using a Multimer Detection System-Oligomeric Aβ (MDS-OAβ) after incubation with spiked synthetic Aβ.

OBJECTIVE

We evaluated the clinical sensitivity and specificity of the MDS-OAβ values for prediction of AD.

METHODS

The MDS-OAβ values measured using inBlood™ OAβ test in heparin-treated plasma samples from 52 AD patients in comparison with 52 community-based subjects with normal cognition (NC). The inclusion criterion was proposed by the NINCDS-ADRDA and additionally required at least 6 months of follow-up from the initial clinical diagnosis in the course of AD.

RESULTS

The MDS-OAβ values were 1.43±0.30 ng/ml in AD and 0.45±0.19 (p < 0.001) in NC, respectively. Using a cut-off value of 0.78 ng/ml, the results revealed 100% sensitivity and 92.31% specificity.

CONCLUSION

MDS-OAβ to measure plasma Aβ oligomerization is a valuable blood-based biomarker for clinical diagnosis of AD, with high sensitivity and specificity.

Cupriavidus cauae sp. nov., isolated from blood of an immunocompromised patient

A novel Gram-stain-negative, facultative aerobic and rod-shaped bacterium, designated as MKL-01^T and isolated from the blood of immunocompromised patient, was genotypically and phenotypically characterized. The colonies were found to be creamy yellow and convex. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences revealed that strain MKL-01^T was most closely related to Cupriavidus gilardii LMG 5886^T, present within a large cluster in the genus Cupriavidus. The genome sequence of strain MKL-01^T showed the highest average nucleotide identity value of 92.1 % and digital DNA-DNA hybridization value of 44.8 % with the closely related species C. gilardii LMG 5886^T. The genome size of the isolate was 5 750 268 bp, with a G+C content of 67.87 mol%. The strain could grow at 10-45 °C (optimum, 37-40 °C), in the presence of 0-10 % (w/v) NaCl (optimum, 0.5%) and at pH 6.0-10.0 (optimum, pH 7.0). Strain MKL-01^T was positive for catalase and negative for oxidase. The major fatty acids were C_16 : 0, summed feature 3 (C_16 : 1  ω7c/C_16 : 1  ω6c and/or C_16 : 1  ω6c/C_16 : 1  ω7c) and summed feature 8 (C_18 : 1  ω7c and/or C_18 : 1  ω6c). The polar lipid profile consisted of phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and one unidentified polar lipid. Moreover, strain MKL-01^T contained ubiquinone Q-8 as the sole respiratory quinone. Based on its molecular, phenotypic and chemotaxonomic properties, strain MKL-01^T represents a novel species of the genus Cupriavidus; the name Cupriavidus cauae sp. nov. is proposed for this strain. The type strain is MKL-01^T.

The impact of environmental variables on the spread of COVID-19 in the Republic of Korea

Corona virus disease 2019 (COVID-19) has been declared a global pandemic and is a major public health concern worldwide. In this study, we aimed to determine the role of environmental factors, such as climate and air pollutants, in the transmission of COVID-19 in the Republic of Korea. We collected epidemiological and environmental data from two regions of the Republic of Korea, namely Seoul metropolitan region (SMR) and Daegu-Gyeongbuk region (DGR) from February 2020 to July 2020. The data was then analyzed to identify correlations between each environmental factor with confirmed daily COVID-19 cases. Among the various environmental parameters, the duration of sunshine and ozone level were found to positively correlate with COVID-19 cases in both regions. However, the association of temperature variables with COVID-19 transmission revealed contradictory results when comparing the data from SMR and DGR. Moreover, statistical bias may have arisen due to an extensive epidemiological investigation and altered socio-behaviors that occurred in response to a COVID-19 outbreak. Nevertheless, our results suggest that various environmental factors may play a role in COVID-19 transmission.

Aβ Accumulation in Vmo Contributes to Masticatory Dysfunction in 5XFAD Mice

Alzheimer's disease (AD) shows various symptoms that reflect cognitive impairment and loss of neural circuit integrity. Sensory dysfunctions such as olfactory and ocular pathology are also observed and used as indicators for early detection of AD. Although mastication is suggested to correlate with AD progression, changes in the masticatory system have yet to be established in transgenic animal models of AD. In the present study, we have assessed pathologic hallmarks of AD with the masticatory behavior of 5XFAD mice. We found that masticatory efficiency and maximum biting force were decreased in 5XFAD mice, with no significant change in general motor function. Immunohistochemical analysis revealed significant accumulation of Aβ (amyloid β), increased microglia number, and cell death in Vmo (trigeminal motor nucleus) as compared with other cranial motor nuclei that innervate the orofacial region. Masseter muscle weight and muscle fiber size were also decreased in 5XFAD mice. Taken together, our results demonstrate that Aβ accumulation in Vmo contributes to masticatory dysfunction in 5XFAD mice, suggesting a close association between masticatory dysfunction and dementia.

Association of Bone Mineral Density to Cerebral Small Vessel Disease Burden

OBJECTIVE

To test the hypothesis that bone mineral loss is mechanistically related to cerebral small vessel disease (SVD), we investigated the relationship between bone mineral density and the prevalence and intensity of SVD among patients with stroke.

METHODS

We analyzed data of 1,190 consecutive patients with stroke who were >50 years of age and underwent both brain MRI and dual-energy x-ray absorptiometry from the stroke registry of Chung-Ang University Hospital in Seoul, Korea. The patients were categorized into 3 groups according to their bone mineral density (normal, osteopenia, and osteoporosis). White matter hyperintensities, silent lacunes, cerebral microbleeds, and extensive perivascular space were assessed from brain MRI. Multinomial logistic regression model was used to examine the association between osteoporosis and total SVD score. We also recruited 70 patients with stroke to study serum bone turnover markers and microRNAs related to both cerebral atherosclerosis and bone metabolism to understand bone and brain interaction.

RESULTS

Osteoporosis was determined among 284 patients (23.9%), and 450 patients (37.8%) had osteopenia. As bone mineral density decreased, total SVD score and the incidence of every SVD phenotype increased except strictly lobar cerebral microbleeds. Multinomial logistic regression analysis showed that osteoporosis was independently associated with severe SVD burden. The levels of microRNA-378f were significantly increased among the patients with osteoporosis and maximal total SVD score and positively correlated with parathyroid hormone and osteocalcin.

CONCLUSIONS

These findings suggest a pathophysiologic link between bone mineral loss and hypertensive cerebral arteriolar degeneration, possibly mediated by circulating microRNA.

Clinical Features, Epidemiology, and Climatic Impact of Genotype-specific Human Metapneumovirus Infections: Long-term Surveillance of Hospitalized Patients in South Korea

Background

Human metapneumovirus (hMPV) commonly causes upper and lower respiratory tract infections. Here, we performed long-term retrospective surveillance of hMPV infection among patients hospitalized in South Korea between 2007 and 2016 and investigated seasonal dynamics and clinical characteristics associated with each virus subtype/genotype.

Methods

Patient specimens were tested for hMPV and other respiratory viruses by commercial molecular assays. Medical records of hMPV-positive patients were reviewed, and hMPV subtype/genotype analysis was performed. We also collected meteorological data and analyzed relationships with hMPV activity.

Results

Of 23 694 specimens, 1275 (5.4%) were positive; among them, 94.0% were classified into 5 subtypes (A1, A2a, A2b, B1, and B2). Some clinical manifestations differed according to hMPV genotype; however, there was no correlation between hMPV subtype and clinical outcome. Viral activity peaked at 13–20 weeks (April and May) and was associated with climate-specific factors, including temperature, relative humidity, diurnal temperature variation, wind speed, and sunshine duration.

Conclusions

This large-scale, 10-year study provides valuable information about the clinical characteristics associated with hMPV subtypes and climate factors contributing to virus transmission.

Antibody kinetics and serologic profiles of SARS-CoV-2 infection using two serologic assays

Background

Coronavirus disease 2019 (COVID-19) is an emerging threat worldwide. This study aims to assess the serologic profiles and time kinetics of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in patients with COVID-19 using two immunoassays.

Methods

A total of 97 samples serially collected from 17 patients with COVID-19 and 137 negative control samples were analyzed for IgM and IgG against SARS-CoV-2 using the AFIAS COVID-19 Ab (Boditech Med Inc., Chuncheon, Republic of Korea) and the EDI^™ Novel Coronavirus COVID-19 ELISA Kit (Epitope Diagnostics, Inc., San Diego, CA).

Results

With both assays, IgM and IgG rapidly increased after 7 days post symptom onset (PSO). IgM antibody levels reached a peak at 15–35 d PSO and gradually decreased. IgG levels gradually increased and remained at similar levels after 22–35 d. The diagnostic sensitivities of IgM/IgG for ≤14d PSO were 21.4%/35.7~57.1% and increased to 41.2~52.9%/88.2~94.1% at >14 d PSO with specificities of 98.5%/94.2% for AFIAS COVID-19 Ab and 100.0%/96.4% for EDI^™ Novel Coronavirus COVID-19 ELISA Kit. Among 137 negative controls, 12 samples (8.8%) showed positive or indeterminate results.

Conclusions

The antibody kinetics against SARS-CoV-2 are similar to common findings of acute viral infectious diseases. Antibody testing is useful for ruling out SARS-CoV-2 infection after 14 d PSO, detecting past infection, and epidemiologic surveys.

Robot-Assisted Partial Nephrectomy for Treatment of Juxtaglomerular Cell Tumor of the Kidney: A Case Report

Background: A juxtaglomerular cell tumor (JGCT), or a reninoma, is a rare renal tumor that can cause secondary hypertension. This is the first reported JGCT that was resected through robotic surgery. Case: We present a case of a 27-year-old female patient with 1.35-cm-sized JGCT in the lower pole of the right kidney. We effectively removed a JGCT through robot-assisted partial nephrectomy without any complications. Conclusion: The robot-assisted partial nephrectomy procedure could be a suitable choice for JGCT resection.

A new aortoiliac calcification scoring system to predict grade C anastomotic leak following rectal cancer surgery

BACKGROUND

Aortoiliac calcification may be a surrogate marker of decreased visceral perfusion causing anastomotic leak (AL). The aim of this study was to evaluate the predictive role of aortoiliac calcification for AL after rectal cancer surgery.

METHODS

We enrolled patients with primary rectal cancer who had restorative resection at our institution between January 2013 and December 2015. An aortoiliac calcification score was calculated as the sum of calcification scores at the infrarenal aorta (0: no, 1: ≤ 3 cm, 2: > 3 cm) and the common iliac arteries (0: no, 1: unilateral, 2: bilateral). AL was classified into three grades: grade A, requiring no intervention; grade B, requiring therapeutic intervention without re-laparotomy; and grade C, requiring re-laparotomy. Clinicopathological characteristics were analyzed to identify risk factors for AL.

RESULTS

There were 583 patients. Three-hundred forty-five (59.2%) had an aortoiliac calcification score ≥ 3, and 37 (6.3%) patients experienced AL, in 30 cases (5.1%) grade C AL. Patients with an aortoiliac calcification score ≥ 3 had a higher incidence of grade C AL (6.7% vs. 2.9%, p = 0.045). Multivariate logistic regression analysis revealed that an aortoiliac calcification score ≥ 3 was an independent risk factor for grade C AL (odds ratio = 2.669, 95% confidence interval 1.066-6.686, p = 0.036).

CONCLUSIONS

Aortoiliac calcification may be considered a risk factor for grade C AL after rectal cancer surgery.

Comparative outcomes of robot-assisted minimally invasive versus open esophagectomy in patients with esophageal squamous cell carcinoma: a propensity score-weighted analysis

Robots are increasingly used in minimally invasive surgery. We evaluated the clinical benefits of robot-assisted minimally invasive esophagectomy (RAMIE) in comparison with the conventional open esophageal surgery. From 2012 to 2016, 371 patients with esophageal squamous cell carcinoma underwent an Ivor Lewis or McKeown procedure at our institution. Of these, 130 patients underwent laparoscopic gastric conduit formation followed by RAMIE, whereas 241 patients underwent conventional esophageal surgery, including laparotomy and open esophagectomy (OE). We compared the short- and long-term clinical outcomes of these patients using the propensity score-based inverse probability of treatment weighting technique (IPTW). Among the early outcomes, the OE group showed a higher incidence of pneumonia (P = 0.035) and a higher requirement for vasopressors (P = 0.001). Regarding the long-term outcomes, all-cause mortality was significantly higher (P = 0.001) and disease-free survival was lower (P = 0.006) in the OE group. Wound-related problems also occurred more frequently in the OE group (P = 0.020) during the long-term follow-up. There was no statistical intergroup difference in the recurrence rates (P = 0.191). The Cox proportional-hazard analysis demonstrated that wound problems (HR 0.16, 95% CI 0.02-0.57; P = 0.017), pneumonia (HR 0.23, 95% CI 0.06-0.68; P = 0.019), and use of vasopressors (HR 0.14, 95% CI 0.08-0.25; P = 0.001) were independent predictors of mortality. RAMIE could be a better surgical option for selected patients with esophageal squamous cell carcinoma.

Top-down and bottom-up approaches for the estimation of measurement uncertainty in coagulation assays

Background

The assessment of measurement uncertainty (MU) in clinical laboratories is essential to the reliable interpretation of results in clinical laboratories. However, despite the introduction of various methods for the expression of uncertainty in measurement, the MUs of coagulation tests have not been extensively studied. The aim of this study was to quantify the MU of various coagulation assays according to international guidelines and to report an expected confidence in the quality of coagulation assays.

Methods

We selected activated partial thromboplastin time, international normalized ratio (INR), protein C/S, antithrombin, fibrinogen, and Factor V/VIII/X to quantify the MUs of two coagulation testing systems: ACL TOP 750 CTS (Instrumentation Laboratory, Bedford, MA, USA) and STA Compact (Diagnostica Stago, Asnières-sur-Seine, France). We used international standards and interlaboratory comparison results in accordance with international guidelines in a top-down approach to the assessment of MU. For INR, MU was estimated in a bottom-up approach using reference thromboplastin and certified plasmas.

Results

Top-down approaches resulted in MUs between 3.3% and 21.3% for each measurand. In the bottom-up approach, MUs of INR values ranged from 10.9% to 26.4% and showed an upward trend as INR increased.

Conclusions

In this study, we were successful in quantifying MU of coagulation assays using practical methods. Our results demonstrated that top-down and bottom-up approaches were adequate for coagulation assays. However, some assays showed significant biases against international standards; therefore, standardization would be necessary to ensure more reliable patient results.

P1416 Clinical importance of consecutive transthoracic echocardiography in the patients with hypertrophic cardiomyopathy

Funding Acknowledgements

nothing

OnBehalf

nothing

Background

prediction of outcomes Hypertrophic cardiomyopathy (HCM) have been robustly analyzed with echocardiography. However, there is limited data of serial follow-up (FU) transthoracic echocardiography (TTE) to predict outcomes in patients with HCM.

Objectives

This study aim is to discover clinical predictors associated with consecutive TTE follow-up in patients with HCM.

Methods

From 2010 to 2016, 162 patients with HCM were enrolled retrospectively. Concentric LVH and others systolic disease related to wall thickness were excluded. Index TTE (baseline) was measured when firstly admitted in our hospital. FU TTE was analyzed at the end of follow-up, defined as the last recorded value in patients who did not develop events or the last recorded value before events developed.

Results

The average of FU TTE and clinical FU period was 3.7 ± 2.0 years. Clinical outcomes were defined as stroke, syncope, heart failure, arrhythmia and death. Interestingly, only baseline TR V max was a predictor for clinical outcome whereas the others echo parameters were not associated with events (Table 1). KM curve showed the TR Vmax ≥2.5m/s was also significant (log rank = 0.008, Fig 1.)

Conclusions Our study showed short-term FU TTE did not bring clinician with clinical benefits in the aspect of prediction for events. Only baseline TR V max was good correlation with cardiovascular outcomes and even in the survival analysis.

Serial TTE and changed values Total N = 162 index TTE (baseline) FU TTE Change of FU per year event no event p-value event no event p-value event no event p-value IVDd, mm 14 ± 4 15 ± 5 0.500 15 ± 5 14 ± 5 0.758 0.23 ± 0.51 -0.07 ± 1.27 0.200 LVIDd, mm 47 ± 5 48 ± 6 0.256 47 ± 7 48 ± 6 0.560 -0.22 ± 2.79 0.10 ± 2.27 0.444 LVEF, % 62 ± 5 61 ± 7 0.379 61 ± 6 61 ± 10 0.927 -0.43 ± 3.10 -0.04 ± 4.94 0.620 LAVI 43 ± 9 43 ± 8 0.879 57 ± 27 58 ± 23 0.849 0.53 ± 14.5 3.11 ± 7.2 0.134 EA ratio 0.9 ± 0.6 0.9 ± 0.6 0.782 1.0 ± 0.8 0.9 ± 0.6 0.595 -0.02 ± 0.76 0.003 ± 0.027 0.594 DT,ms 196 ± 58 201 ± 62 0.603 203 ± 91 217 ± 89 0.370 17 ± 57 5 ± 40 0.154 septal e` 4.4 ± 2.1 4.2 ± 1.6 0.585 4.4 ± 1.6 4.6 ± 1.7 0.438 0.24 ± 0.91 0.05 ± 0.65 0.190 E of e` 17 ± 11 17 ± 23 0.993 15 ± 9 15 ± 6 0.726 -0.48 ± 4.42 -1.66 ± 22.78 0.728 TR velocity 2.6 ± 0.5 2.4 ± 0.4 0.012 2.7 ± 0.6 2.6 ± 0.4 0.604 0.05 ± 0.30 0.04 ± 0.18 0.905 Max wall thickness 17 ± 3 18 ± 3 0.137 17 ± 4 17 ± 3 0.888 -0.01 ± 2.19 -0.18 ± 1.14 0.522

Abstract P1416 Figure. TR Vmax and CV outcomes in the KM curve

Assessing the measurement uncertainty of qualitative analysis in the clinical laboratory

Measurement uncertainty is a parameter that is associated with the dispersion of measurements. Assessment of the measurement uncertainty is recommended in qualitative analyses in clinical laboratories; however, the measurement uncertainty of qualitative tests has been neglected despite the introduction of many adequate methods. We herein provide an overview of three reasonable statistical methods for quantifying the measurement uncertainties of qualitative assays, namely Bayes’ theorem, the normal distribution method, and the information theoretic approach. Unlike in quantitative analysis, the measurement uncertainty of qualitative analysis is expressed using a conditional probability, likelihood ratio, and entropy. With the necessary theoretical background, the practical applications for clinical laboratories are also provided using statistical calculations. Using statistical approaches, we hope that our review will contribute to the use of measurement uncertainty in qualitative analyses in the clinical laboratory environment.

Hyperprogressive disease during PD-1/PD-L1 blockade in patients with non-small-cell lung cancer

BACKGROUND

Immune checkpoint blockade with Programmed cell death 1 (PD-1)/PD-L1 inhibitors has been effective in various malignancies and is considered as a standard treatment modality for patients with non-small-cell lung cancer (NSCLC). However, emerging evidence show that PD-1/PD-L1 blockade can lead to hyperprogressive disease (HPD), a flair-up of tumor growth linked to dismal prognosis. This study aimed to evaluate the incidence of HPD and identify the determinants associated with HPD in patients with NSCLC treated with PD-1/PD-L1 blockade.

PATIENTS AND METHODS

We enrolled patients with recurrent and/or metastatic NSCLC treated with PD-1/PD-L1 inhibitors between April 2014 and November 2018. Clinicopathologic variables, dynamics of tumor growth, and treatment outcomes were analyzed in patients with NSCLC who received PD-1/PD-L1 blockade. HPD was defined according to tumor growth kinetics (TGK), tumor growth rate (TGR), and time to treatment failure (TTF). Immunophenotyping of peripheral blood CD8+ T lymphocytes was conducted to explore the potential predictive biomarkers of HPD.

RESULTS

A total of 263 patients were analyzed. HPD was observed in 55 (20.9%), 54 (20.5%), and 98 (37.3%) patients according to the TGK, TGR, and TTF. HPD meeting both TGK and TGR criteria was associated with worse progression-free survival [hazard ratio (HR) 4.619; 95% confidence interval (CI) 2.868-7.440] and overall survival (HR, 5.079; 95% CI, 3.136-8.226) than progressive disease without HPD. There were no clinicopathologic variables specific for HPD. In the exploratory biomarker analysis with peripheral blood CD8+ T lymphocytes, a lower frequency of effector/memory subsets (CCR7-CD45RA- T cells among the total CD8+ T cells) and a higher frequency of severely exhausted populations (TIGIT+ T cells among PD-1+CD8+ T cells) were associated with HPD and inferior survival rate.

CONCLUSION

HPD is common in NSCLC patients treated with PD-1/PD-L1 inhibitors. Biomarkers derived from rationally designed analysis may successfully predict HPD and worse outcomes, meriting further investigation of HPD.

Age-Specific Cutoffs of the Sysmex UF-1000i Automated Urine Analyzer for Rapid Screening of Urinary Tract Infections in Outpatients

We investigated the usefulness of age-specific cutoffs for screening of urinary tract infections (UTIs) in Korean outpatients, using the automated urine analyzer UF-1000i (Sysmex, Kobe, Japan). We retrospectively reviewed outpatient medical records. Urine samples of 7,443 outpatients from January 2010 to December 2017 were analyzed using urine culture and UF-1000i. ROC curves were calculated for each UF-1000i parameter based on the culture results. There were 1,398 culture positive samples, 5,774 culture negative samples, and 271 contaminated samples. UF-1000i had an area under the curve of ≥0.9 in outpatients >15 years. The appropriate cutoffs, which are the sum of bacterial (B-A-C) and white blood cell (WBC) counts, were 297.10/µL (15–24 years), 395.65/µL (25–44 years), 135.65/µL (45–64 years), 67.95/µL (65–74 years), and 96.5/µL (≥75 years). B-A-C and WBC counts differed among the three most frequently identified bacteria (Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis). The UF-1000i system is useful for applying age-specific cutoffs to screen for UTIs, thereby preventing antibiotic abuse and reducing antibiotic resistance. Future studies can explore how its B-A-C and WBC counts can facilitate selection of empirical antibiotics by distinguishing between gram-positive and gram-negative bacteria.

Analytical performance of newly developed rapid point-of-care test for the simultaneous detection of hepatitis A, B, and C viruses in serum samples

ABSTRACTBACKGROUND

Although immunoassays play a major role in the detection of hepatitis viruses, there is a need for a point-of-care (POC) test. We evaluated the EuDx-HE (A,B,C) kit (EUDIPIA, Cheongju, Korea), which detects anti-hepatitis A virus (HAV) immunoglobulin M (IgM), hepatitis B virus surface antigen (HBsAg), and anti-hepatitis C virus (HCV) immunoglobulin G (IgG) simultaneously using an immunochromatographic method within 15 minutes.

METHODS

A total of 1581 serum samples including 57, 477, and 451 samples positive for anti-HAV IgM, HBsAg, and anti-HBV IgG, respectively, were analyzed. We investigated the diagnostic accuracy of the EuDx-HE (A,B,C) kit by comparison with SD BIOLINE POC kits (Abbott, Chicago, IL) using Architect immunoassays as a reference method.

RESULTS

For anti-HAV IgM and HBsAg detection, the EuDx-HE (A,B,C) kit showed a higher sensitivity and a slightly lower specificity than the SD BIOLINE kit. For anti-HCV IgG detection, the EuDx-HE (A,B,C) kit had a higher sensitivity and a higher specificity than the SD BIOLINE kit. The agreement for positivity between the POC tests was >89.47%, with κ values of 0.844, 0.941, and 0.943 for HAV, HBV, and HCV, respectively.

CONCLUSION

The EuDx-HE (A,B,C) kit showed an acceptable clinical performance for detecting anti-HAV IgM, HBsAg, and anti-HCV.

Impact of bacterial and viral coinfection in community-acquired pneumonia in adults

Bacterial and viral coinfected community-acquired pneumonia (CAP) is poorly characterized in adults. The aim of this study was to investigate the influence of bacterial and viral coinfection in patients with CAP. A total of 235 adults who requested molecular tests of pneumonia and were diagnosed with CAP were enrolled in this study. Microbiological tests included blood and sputum cultures, PCR for bacterial and viral pathogens, antigen test for Streptococcus pneumoniae and the influenza virus, and antibody detection of Mycoplasma pneumonia. Of the 235 patients, 32 (13.6%) patients were coinfected with bacteria and virus. Among 64 severe CAP patients, the concurrent infections were confirmed in 14 patients (21.9%). The proportion of severe pneumonia was significantly higher in patients with coinfection, and they showed a significantly higher mortality rate. In conclusion, bacterial and viral coinfection in CAP is not a rare occurrence in adults. Viral and bacterial coinfections have an adverse impact on the severity of the pneumonia, and increase morbidity and mortality in patients with CAP.

•

13.6% CAP patients and 21.9% severe CAP patients were coinfected with bacteria and virus in adults.

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Bacterial and viral coinfection may adversely impact the severity of pneumonia.

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Concurrent infection also increases the morbidity in adult patients with CAP.