Establishing the blood reference interval of pancreatic elastase-1: A prospective study.

BACKGROUND AND AIM: Pancreatic elastase-1 (PE-1) has been investigated in pancreatic disorders. However, the reference interval (RI) of PE-1 in blood remains unconfirmed. We aimed to establish the blood RI of PE-1 in an adult population. METHODS: In this prospective cross-sectional study, we enrolled 400 adults who had received the whole-body physical check-up program between May 1, 2019 and November 20, 2019. The serum and plasma PE-1 levels were measured by latex turbidimetric immunoassay in different storage conditions (fresh, refrigerated, and frozen). The 95% and 99% RI of PE-1 were calculated according to the Clinical & Laboratory Standards Institute guidelines. The correlations between PE-1 and other parameters were analyzed using multivariable regression models. Ultimately, 38 patients with acute pancreatitis were prospectively recruited as the validation cohort. RESULTS: The PE-1 levels in fresh serum were highly correlated with those in refrigerated (R2  = 0.998) or frozen (R2  = 0.942) samples; however, plasma should not be suggested in frozen conditions (plasma vs serum: R2  = 0.185). In the RI study population (202 male & 198 female participants), the median age was 52.6 (25-75% interquartile range: 43.1-61.0). The 95% and 99% RIs of PE-1 were 30.0-221.0 and 22.0-359.0 ng/dL, respectively. Triglycerides (ß = 0.106, P = 0.033), lipase (ß = 0.154, P = 0.007), and CA19-9 (ß = 0.130, P = 0.008) were independent factors associated with PE-1. In the pancreatitis validation cohort, with a cut-off value of 359.0 ng/dL, the sensitivity and specificity were 100% and 99.8%, respectively. CONCLUSION: The RI of PE-1 established in this study can be used for further applications. Serum is the suggested form for frozen sample storage.

Effects of Analyzer Detection Method, Ethnicity, and Reference Individuals on Reference Interval of Immature Platelet Fraction.

BACKGROUND: Immature platelet fraction (IPF) is a new biomarker for thrombopoiesis and inflammation. However, the reference interval (RI) is wildly discrepant among published reports. This study aimed to establish the RI of IPF for a population in Taiwan and evaluate the effects the detection method of the analyzer, ethnicity, and reference individuals have on the RI of IPF. METHODS: The RI of absolute IPF (A-IPF) and IPF% were established with healthy subjects from the outpatient services of the Health Management Department of Taichung Veterans General Hospital between January 1, 2015 and March 1, 2016. These values were used along with published reports for meta-analysis. RESULTS: A-IPF (109/L) and IPF% of Taiwanese were 6.9 - 7.6 and 3.1 - 3.4, respectively. Significant differences were found when performing paired comparisons of the RI of A-IPF and IPF% published in reports. For A-IPF, there was only one paired comparison with a significant difference (Z > 1.96) across 6 reports. Thus, the contribution of the factors examined on the RI of IPF cannot be determined. For IPF%, there were 8 paired comparisons with significant differences across 10 reports. The discrepancy rates of RI for IPF% were 41.2%, 50.0%, and 25.0% with the difference of reference individuals, the analyzer method, and ethnicity, respectively. CONCLUSIONS: The RIs of Taiwanese for A-IPF and IPF% were established. Furthermore, the analyzer detection method and the reference individuals contribute to the discrepancy of the RI for IPF% and should be considered cautiously when the value of IPF is interpreted.

Confirmed False Positive Proteinuria in Patients with Systemic Lupus Erythematosus Taking Hydroxychloroquine: a Spot Sample Measurement.

BACKGROUND: A false-positive screening result is associated with harmful treatment or follow-up costs. This study aimed to estimate the rate of false positive proteinuria with the dipstick in patients with systemic lupus erythematosus (SLE) taking hydroxychloroquine. METHODS: A total of 334 patients with a positive dipstick and confirmed by total urine protein with quantification assay were enrolled. The experimental group included those with SLE taking hydroxychloroquine, and the rest was the control group. The difference of the rate of false positive in the dipstick was analyzed using the chi-square test and odds ratio (OR) between groups. Qualitative tracking of potential interference in the dipstick was performed. RESULTS: The results revealed that the rate of false positive with a dipstick for the experimental and control groups were 29.5% and 5.0% (p = 0.000), respectively. The OR with 95% confidence interval (CI) of the rate of false positive for the experimental group with respect to the control group was 5.95 (95% CI: 2.80 - 12.65). Qualitative tracking showed that the dipstick was influenced to become false-positive when hydroxychloroquine concentration was ≥ 30 mg/dL. CONCLUSIONS: Hydroxychloroquines like plaquenil or geniquin may lead to a high rate of false positive with the dipstick method. A quantification assay is recommended for proteinuria measurement in patients with SLE taking hydroxychloroquines.

A Point-of-Care Prothrombin Time Test on a Microfluidic Disk Analyzer Using Alternate Spinning.

In this study, we conducted a fully integrated point-of-care prothrombin time test on a microfluidic disk analyzer. The microfluidic functions integrated on the disk were capable of separating whole blood, decanting plasma, and mixing it with reagents in sequence under alternate spinning. The assay protocol was completed by alternate spinning without using microvalves or surface modification. Clinical sample tests on prothrombin time measurement were conducted by both the microfluidic disk analyzer and the reference instrument used in medical centers. The test results showed a good correlation and agreement between the two instruments.

Evaluating the performance of urine conductivity as screening for early stage chronic kidney disease.

BACKGROUND: This study aimed to determine if urine conductivity (Cond) is better for screening early stage chronic kidney disease (CKD) instead of the currently routinely used parameters of urine creatinine (UCr), urine osmolality (Osmo), urine specific gravity (SpGr), and urine protein (UP). METHODS: One hundred and forty participants (86 male, 54 female) with eGFR > 60 were grouped as either early stage CKD (kidney damage longer than 3 months with either structural or functional abnormalities [n = 72]) or the control group (without CKD and without kidney damage or functional abnormalities [n = 681]). Sensitivty (Sn) and specificity (Sp) of UP and the ROC curves were calculated. The area under the curve (AUC) with 95% confidence interval (CI) was used to compare Cond, UCr, Osmo, and SpGr. Pearson's correlation was used to analyze the correlation between Cond and UCr, Osmo, and SpGr in the early stage CKD group. RESULTS: The Sn and Sp of UP were 22.2% and 92.6%, respectively. By ROC analysis, Cond had the largest AUC (0.752, 95% CI: 0.672-0.832), with 52.9% Sn and 86.1% Sp. Pearson's correlation showed that the coefficient (p < 0.01) of Cond to UCr, Osmo, and SpG were 0.696, 0.907, and 0.820, respectively. CONCLUSIONS: Cond has better screening ability than UP for early stage CKD and may be a potential surrogate parameter for Osmo, SpGr and UCr.

Bloodstream Coinfections and Antimicrobial Resistance in Hospitalized COVID-19 Patients: A Single-center Retrospective Study.

BACKGROUND/AIM: Bloodstream infections in patients with COVID-19 are linked to higher mortality rates, whilst data on epidemiology and resistance patterns remains scarce to guide management and prevent antibiotic resistance. This research focuses on the prevalence, clinical features, causative microorganisms, and antimicrobial susceptibility of bacterial and fungal secondary bloodstream co-infections in hospitalized patients with COVID-19. PATIENTS AND METHODS: In this retrospective study analysis of 230 patients with COVID-19 from Central Taiwan (June 2021 to June 2022), pathogens were identified via MALDI-TOF MS and Vitek 2 system with Clinical & Laboratory Standards Institute (CLSI) standards. RESULTS: In the cohort, 17.8% experienced bloodstream infections, resulting in a total of 45 isolates from the 41 bloodstream infection patients: predominantly gram-positive bacteria (Staphylococcus and Enterococcus) at 69%, gram-negative at 29% (Escherichia coli and Klebsiella pneumoniae), and fungi at 2%. Infected patients showed significantly elevated levels of white blood count (WBC), C-reactive protein (CRP) and procalcitonin (PCT). Of note, resistance to common antibiotics, such as fluoroquinolones, cephalosporins, and oxacillin was significant, especially in K. pneumoniae, Acinetobacter species, and S. aureus infections. CONCLUSION: Our study highlights the influence of bacterial infections in hospitalized patients with COVID-19. The bacterial infections were discovered to impact the clinical trajectory of COVID-19, potentially exacerbating or mitigating its symptoms, severity and fatality. These insights are pivotal to addressing clinical challenges in COVID-19 management and underscoring the need for tailored medical interventions. Understanding these co-infections is thus essential for optimizing patient care and improving overall outcomes in the post COVID-19 pandemic era.

Screening Cases of Suspected Early Stage Chronic Kidney Disease from Clinical Laboratory Data: The Comparison between Urine Conductivity and Urine Protein.

(1) Background: Chronic kidney disease (CKD) affects more than 800 million global population. Early detection followed by clinical management is among the best approaches for the affected individuals. However, a sensitive screening tool is not yet available. (2) Methods: We retrospectively reviewed 600 patients aged >20 years with a full range of estimated glomerular filtration rate (eGFR) for clinical assessment of kidney function between 1 January 2020, to 30 April 2021, at the Taichung Veterans General Hospital, Taichung, Taiwan. With stratified sampling based on the level of eGFR, participants were evenly grouped into training and validation sets for predictive modeling. Concurrent records of laboratory data from urine samples were used as inputs to the model. (3) Results: The predictive model proposed two formulae based on urine conductivity for detecting suspected early-stage CKD. One formula, P_male45, was for used male subjects aged ≥45 years, and it had a prediction accuracy of 76.3% and a sensitivity of 97.3%. The other formula, P_female55, was used for female subjects aged ≥55 years. It had a prediction accuracy of 81.9% and a sensitivity of 98.4%. Urine conductivity, however, had low associations with urine glucose and urine protein levels. (4) Conclusion: The two predictive models were low-cost and provided rapid detection. Compared to urine protein, these models had a better screening performance for suspected early-stage CKD. It may also be applied for monitoring CKD in patients with progressing diabetes mellitus.

Accuracy of Point-of-Care Blood Glucometers in Neonates and Critically Ill Adults.

PURPOSE: Inpatient glycemic management has become a common issue because of the increasing number of hospitalized patients with hyperglycemia. Point-of-care devices can enable timely inpatient glucose monitoring, which may lead to better outcomes. The accuracy of point-of-care testing in various clinical scenarios has been questioned, particularly in neonates and critically ill patients. This study aimed to evaluate the accuracy of the CONTOUR PLUS and CONTOUR PLUS ONE glucometers (new wireless systems that link to a smart mobile device) when used as point-of-care devices for blood glucose monitoring in neonates and critically ill adults in inpatient settings. METHODS: This cross-sectional study was conducted at a medical center in central Taiwan and enrolled patients admitted to the neonatal intensive care unit, sick child room, or respiratory intensive care unit between November 2020 and April 2021. Neonates with suspected infection or abnormal blood coagulation and adults who had abnormal blood coagulation, were pregnant, had received organ transplants, or had undergone massive blood transfusions were excluded. The accuracy of the glucometers was determined based on the following criteria of the International Organization for Standardization (ISO) standard: 15197:2013. FINDINGS: Overall, 114 neonates (mean age, 4.2 days [range, 0-28 days]; 65 boys [57.0%]) and 106 hospitalized critically ill adults (mean age, 68.2 years [range, 27-94 years]; 72 men [67.9%]) were enrolled in this study. The glucose values obtained with each glucometer had good precision, and all findings met the reference criteria of the within-lot results. All measurements of the neonates' venous blood by each glucometer met the accuracy criteria specified by ISO standard 15197:2013. Furthermore, 98.1% and 97.2% of the arterial blood glucose measurements for critically ill adults obtained with CONTOUR PLUS and CONTOUR PLUS ONE met the accuracy criteria, respectively. IMPLICATIONS: Both glucose management systems met the accuracy criteria for venous blood from neonates and arterial blood from critically ill adults. Thus, the use of these 2 point-of-care devices in inpatient settings, including for neonates and critically ill adults, can be recommended to minimize limitations associated with the clinical application of point-of-care testing in glucose management. The wireless connection may play a role in the subsequent development of institution-wide virtual glycemic management under the supervision of a team of endocrinologists.

Laboratory Surge Response to the COVID-19 Pandemic: An Incident Command System Approach.

The COVID-19 pandemic has reaffirmed the critical significance of effective diagnostics in outbreak response. In Taiwan, the COVID-19 wave in May 2021 led to a rapidly growing demand for SARS-CoV-2 diagnostic tests. To meet the challenge, an extensive system-wide emergency preparedness plan, hospital emergency incident command system (HEICS), was developed to deal with emergencies involving healthcare systems. During the wave of the COVID-19 outbreak, a 19.4-fold increase in SARS-CoV-2 PCR (polymerase chain reaction) diagnostic tests occurred in the hospital. The incident commander of TCVGH reviewed COVID-19 related events daily and purchased a high-throughput PCR machine for SARS-CoV-2 PCR diagnostic tests. In addition, the Department of Operations was responsible for staff scheduling and educational training. The turn-around times of SARS-CoV-2 diagnostic tests were shortened from 21.2 hours to 5.8 hours in the second week of the COVID-19 wave. Implementation of HEICS integrated resources could be helpful for expanding surge capacity during future outbreaks.

Comparison of Fcγ receptor expression on neutrophils with procalcitonin for the diagnosis of sepsis in critically ill patients.

BACKGROUND AND OBJECTIVE: The expression of Fc receptors for IgG (FcγRs) on neutrophils, including CD16, CD32 and CD64, may be modulated in response to sepsis. We investigated the expression of FcγRs on neutrophils and procalcitonin (PCT) as biomarkers of sepsis among critically ill patients. METHODS: This prospective study was conducted in a 24-bed respiratory intensive care unit between July 2007 and June 2008. Critically ill patients requiring mechanical ventilation were enrolled and categorized into three groups: those with systemic inflammatory response syndrome (SIRS), those with severe sepsis and those with septic shock. Expression of FcγRs on neutrophils was quantitatively measured by flow cytometry immediately after enrolment of the patient. Serum PCT levels were also measured. Receiver operating characteristic (ROC) curves were used to evaluate the performance of FcγR expression and PCT as biomarkers of sepsis. RESULTS: Sixty-six patients were enrolled, including 11 with SIRS, 31 with severe sepsis and 24 with septic shock. Nineteen healthy volunteers served as normal controls. CD64 was upregulated, CD16 was downregulated and CD32 remained unchanged during sepsis. CD64 expression and the ratio of CD64/CD16 increased significantly with the severity of sepsis. However, serum PCT levels were not significantly different between SIRS and severe sepsis patients. CD64, CD64/CD16 and PCT all significantly predicted sepsis, septic shock and bacteraemia. As assessed using ROC curves, CD64 was better than PCT for differentiating SIRS from severe sepsis and septic shock. CD64 and CD64/CD16 were associated with mortality. CONCLUSIONS: CD64 and CD16 were differentially modulated by sepsis. CD64, CD64/CD16 and PCT may be biomarkers of sepsis. CD64 was better than PCT for identifying patients who required treatment with antibiotics.

Processing Cycle Efficiency to Monitor the Performance of an Intelligent Tube Preparation System for Phlebotomy Services.

BACKGROUND: The waiting time (WT) for a phlebotomy is directly related to patient satisfaction with a health service. However, the processing time varies widely depending on the type of patients. Monitoring of the WT alone may not enable an effective evaluation of the lean performance of the medical staff for patients with different characteristics. The objective of this study was to use process cycle efficiency (PCE) to assess the performance of an intelligent tube preparation system (ITPS) which automatically labeled test tubes and conducted patient rerouting for phlebotomy services, and to interpret the WT during peak hours. METHODS: Three time periods were used. The baseline period was from 1 July to 31 July 2014. Phase 1 was after the establishment of the ITPS, with patients ≥80 years old being rerouted. In phase 2, patients ≥78 years old were rerouted. Those data were recorded with a calling system and ITPS, respectively. RESULTS: PCE was significantly improved from 12.9% at baseline to 51.1% (p < 0.001) in phase 1 and 53.0% (p < 0.001) in phase 2. The WT of 16.9 min at baseline was reduced to 3.8 min in phase 1 (p < 0.001), and 3.6 min in phase 2 (p < 0.001). Moreover, the results showed that a WT < 10 min was consistent with a PCE ≥ 25%. CONCLUSIONS: Establishing an ITPS for phlebotomy can significantly increase PCE and shorten the WT. Furthermore, the PCE ≥ 25% could be a good assessment reference for the management of appropriate human resources for phlebotomy services, although it is a complex parameter.

Elizabethkingia Intra-Abdominal Infection and Related Trimethoprim-Sulfamethoxazole Resistance: A Clinical-Genomic Study.

(1) Background: Elizabethkingia spp. is an emerging nosocomial pathogen which causes mostly blood stream infection and nosocomial pneumonia. Among Elizabethkingia species, Elizabethkingia anophelis is the major pathogen, but misidentification as Elizabethkingia meningoseptica is a common problem. Elizabethkingia also possesses broad antibiotic resistance, resulting in high morbidity and mortality of the infection. The aim of our study was to review Elizabethkingia intra-abdominal infections and investigate resistance mechanisms against TMP/SMX in Elizabethkingia anophelis by whole genome sequencing. (2) Methods: We retrospectively searched records of patients with Elizabethkingia intra-abdominal infection between 1990 and 2019. We also conducted whole genome sequencing for a TMP/SMX-resistant Elizabethkingia anophelis to identify possible mechanisms of resistance. (3) Results: We identified a total of nine cases of Elizabethkingia intra-abdominal infection in a review of the literature, including our own case. The cases included three biliary tract infections, three CAPD-related infection, two with infected ascites, and two postoperation infections. Host factor, indwelling-catheter, and previous invasive procedure, including surgery, play important roles in Elizabethkingia infection. Removal of the catheter is crucial for successful treatment. Genomic analysis revealed accumulated mutations leading to TMP/SMX-resistance in folP. (4) Conclusions: Patients with underlying disease and indwelling catheter are more susceptible to Elizabethkingia intra-abdominal infection, and successful treatment requires removal of the catheter. The emerging resistance to TMP/SMX may be related to accumulated mutations in folP.

Should sleep laboratories have their own predictive formulas for continuous positive airway pressure for patients with obstructive sleep apnea syndrome?

BACKGROUND: Several formulas predicting optimal continuous positive airway pressure (CPAP) for obstructive sleep apnea treatment have been developed and diverse parameters selected as predictive factors in different sleep laboratories using different ethnic groups. This study aimed to validate a constructed predictive formula for the study laboratory and to test the hypothesis that sleep laboratories should have their own predictive formulas. METHODS: Fifty-seven adult subjects with obstructive sleep apnea syndrome (OSAS) were enrolled in the model-building set and underwent two polysomnography (PSG) studies to diagnose OSAS and titrate for optimal CPAP. A predictive formula, derived from anthropometric and polysomnographic variables, was validated together with two other predictive formulas in 30 subjects by comparing the mean predictive CPAP values, rates of successful prediction, and agreements. RESULTS: Regression analysis showed that apnea-hypopnea index (AHI), SaO2nadir (nadir of arterial oxyhemoglobin saturation by pulse oximetry), and body mass index (BMI) strongly correlated with optimal CPAP. The derived predictive formula for the study laboratory was: CPAPpred (predictive CPAP) = 6.380 + 0.033 × AHI - 0.068 × SaO2nadir + 0.171 × BMI (R(2) = 0.335, adjusted R(2) = 0.298). In Taiwan, different predictive formulas used by different sleep laboratories with different independent predictors led to similar mean predictive CPAP values to the mean observed optimal CPAP values, rates of successful prediction, and agreements with the observed optimal CPAP. There were significant differences between the mean predictive CPAP values and mean observed optimal CPAP values, lower rates of successful prediction, and negatively skewed 95% confidence interval (CI) when using a predictive formula derived from different ethnic populations. CONCLUSION: A sleep laboratory may not need to have its own predictive formula for determining the optimal effective CPAP but should adopt the one derived from the same ethnicity of OSAS patients as the reference formula.

Evidence of intracellular stages in Trypanosoma (Megatrypanum) theileri in non-phagocytic mammalian cells.

Trypanosoma (subgenus Megatrypanum) theileri was first identified over one hundred years ago, and is a widespread parasite in cattle. Its life cycle within the mammalian host has rarely been reported. Whether there is an intracellular stage in tissues is unknown and such a stage has not been demonstrated experimentally. Intriguingly, using Giemsa staining with light microscopy and transmission electron microscopy examination, we found that the parasite was able not only to attach to cells but also to invade several phagocytic and non-phagocytic mammalian cells. Based on these findings, we conducted further investigations using a special antibody in immunofluorescence confocal images. Moreover, we examined a series of possible events of cell invasion in T. theileri. The results revealed that GM1, a marker of membrane rafts, was implicated in the mechanism of entry by this parasite. After incubation with tissue culture trypomastigotes, the gelatinolytic activity was significantly increased and accumulated at the attachment sites. Using ultrastructural localization detection by CytoTracker live imaging and confocal immunofluorescence microscopy, we found that lysosome fusion and the autophagy pathway were engaged in invaginating processes. T. theileri amastigotes also invaded cells and were enclosed by the lysosomes. Furthermore, tissue-cultured trypomastigotes were found to be capable of triggering intracellular free Ca(2+) transients and TGF-ß-signaling. Our findings that intracellular amastigote stages exist in mammalian cells infected with T. theileri and that the invasion processes involved various host cell components and cell signalings were extremely surprising and warrant further investigation.