Associations of Perioperative Red Blood Cell Transfusion With Outcomes of Kidney Transplantation in Korea Over a 16-Year Period.

BACKGROUND: This study investigated the associations between transfusion of different types of red blood cell (RBC) preparations and kidney allograft outcomes after kidney transplantation (KT) over a 16-year period in Korea using a nationwide population-based cohort. METHODS: We investigated the reported use of RBCs during hospitalization for KT surgery, rejection, and graft failure status using nationwide data from the National Health Information Database (2002-2017). The associations between the type of perioperative RBC product and transplant outcomes were evaluated among four predefined groups: no RBC transfusion, filtered RBCs, washed RBCs, and packed RBCs (pRBCs). RESULTS: A total of 17,754 KT patients was included, among which 8,530 (48.0%) received some type of RBC transfusion. Of the patients who received RBC transfusion, 74.9%, 19.7%, and 5.4% received filtered RBCs, pRBCs, or washed RBCs, respectively. Regardless of the type of RBC products, the proportions of acute rejection and graft failure was significantly greater in patients receiving transfusion (P < 0.001). Cox proportional hazards regression analyses showed that the filtered RBC and pRBC groups were significantly associated with both rejection and graft failure. The washed RBC group also had hazard ratios greater than 1.0 for rejection and graft failure, but the association was not significant. Rejection-free survival of the pRBC group was significantly lower than that of the other groups (P < 0.001, log-rank test), and graft survival for the no RBC transfusion group was significantly greater than in the other groups (P < 0.001, log-rank test). CONCLUSION: Perioperative RBC transfusion was associated with poor graft outcomes. Notably, transfusion of pRBCs significantly increased transplant rejection. Therefore, careful consideration of indications for RBC transfusion and selection of the appropriate type of RBCs is necessary, especially for patients at high risk of rejection or graft failure.

Age-group-specific reference intervals for anti-Müllerian hormone and its diagnostic performance for polycystic ovary syndrome in a Korean population.

BACKGROUND: We established age-group-specific reference intervals for serum anti-Müllerian hormone (AMH) levels in a Korean population and investigated the effectiveness of AMH assay for polycystic ovary syndrome (PCOS) diagnosis. METHODS: We analyzed serum levels of AMH, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) from 1540 Korean women. Subjects were divided into three groups: healthy, benign gynecologic diseases, and PCOS. Age-group-specific reference intervals and AMH diagnostic performance were estimated. RESULTS: The PCOS group had a median AMH level of 7.0 µg/L, which was higher than for the healthy (1.8 µg/L) and the benign gynecologic diseases (2.7 µg/L) groups. The upper 97.5% reference limits for age groups 12-20 years, 21-34 years, and 35-46 years were 13.2 µg/L, 15.8 µg/L, and 6.6 µg/L, respectively. The area under the curve (AUC) values to estimate AMH ability to discriminate PCOS from healthy women for each age group were 0.741, 0.785, and 0.789, respectively. AUCs for LH/FSH were 0.719, 0.672, and 0.590. CONCLUSIONS: The better diagnostic ability of AMH over LH/FSH in women of late childbearing ages indicates that age and other clinical characteristics should be considered when interpreting these test results.

Diagnostic performance of CA 125, HE4, and risk of Ovarian Malignancy Algorithm for ovarian cancer.

OBJECTIVE: We evaluated the diagnostic performance of CA 125, HE4, and ROMA for ovarian cancer in Koreans and set optimal cutoffs. METHOD: Serum levels of HE4 and CA 125 and the ROMA score were determined in 762 patients with benign gynecological disease and 70 with ovarian cancer. Receiver operating characteristic curves were constructed to calculate the areas under the curve (AUC). CA 125, HE4, and ROMA exhibiting maximum Youden index were determined, respectively, as the optimal cutoffs, and sensitivity and specificity were evaluated by applying those cutoffs. RESULTS: In benign diseases, CA 125 significantly increased in patients with uterine myoma, adenomyosis, endometrial pathology, or endometriosis, but HE4 only increased in patients with adenomyosis. For the diagnosis of ovarian cancer, the combination of CA 125, HE4, and age showed the highest AUC value of 0.892 in the premenopausal group, and ROMA demonstrated the best diagnostic performance, with an AUC of 0.935 in postmenopausal patients. When the optimal cutoff values for CA 125 and HE4 were applied, the sensitivities of CA 125, HE4, and ROMA in premenopausal women were all the same at 0.714, while the specificities were 0.841, 0.974, and 0.972, respectively. In the postmenopausal group, the sensitivities of these markers were 0.857, 0.804, and 0.929, and the specificities were 0.836, 0.887, and 0.800, respectively. CONCLUSION: Although all markers demonstrated good diagnostic performance, they varied depending on the pathologic types of benign diseases and ovarian cancer. For accurate diagnosis of ovarian cancer, CA 125, HE4, and ROMA should be used complementarily.

Analysis of red blood cell use in elective surgeries over 12 years in Korea.

BACKGROUND: Red blood cell (RBC) transfusion is a lifesaving process for patients with perioperative bleeding, but transfusion can cause adverse events. Effective utilization and management of blood products as a limited resource is essential when considering cost-efficiency and patient safety. STUDY DESIGN AND METHODS: We analyzed the number of RBC units used during the hospitalization of patients who had undergone surgical procedures from 2002 to 2013 using National Health Insurance Service-National Sample Cohort data, which include a total of 487,238 cases for 206 selected operations. RESULTS: RBC units were used in 39,637 (8.1%) cases. A total of 60,815 RBC units were transfused with a mean of 0.13 units per patient overall and a mean of 1.53 units per case receiving RBC transfusion. In addition, 56.7% of the RBC units were transfused for females, and 60.1% of RBC units were transfused into patients aged 60 or older. RBC units were used most often in orthopedic surgeries (33.8%), followed by general surgeries (12.0%) and vascular surgeries (11.8%). The number of operations performed in the cohort increased from 27,690 in 2002 to 49,473 in 2013, and the mean number of RBC units used per operation also increased from 0.08 units in 2002 to 0.15 units in 2013. CONCLUSION: Continuous management for blood preparation and transfusion is needed for efficient utilization of blood. Periodic investigation on the use of blood products through nationwide studies could suggest data applicable to blood product preparation for various elective surgical operations.

The effect of therapeutic leukapheresis on early complications and outcomes in patients with acute leukemia and hyperleukocytosis: a propensity score-matched study.

BACKGROUND: Hyperleukocytosis in acute leukemia is associated with higher early mortality due to the major complications of leukostasis, tumor lysis syndrome (TLS), and disseminated intravascular coagulopathy (DIC). Leukapheresis remains an important modality for the management of patients with acute leukemia and hyperleukocytosis. However, the role of leukapheresis in early mortality is controversial. This study sought to evaluate the prognostic impact of leukapheresis and its beneficial effects on TLS and DIC. STUDY DESIGN AND METHODS: We conducted a propensity score-matched study of 166 patients with acute leukemia and hyperleukocytosis admitted between 2006 and 2016. The incidence of TLS and DIC was determined using well-defined Cairo-Bishop criteria for TLS and International Society of Thrombosis and Haemostasis criteria for DIC. RESULTS: Before matching, 27 of 91 patients (30%) with acute myeloid leukemia (AML) and 32 of 75 patients (43%) with acute lymphoblastic leukemia (ALL) underwent leukapheresis. Propensity score matching was performed to adjust for clinical disparities between the leukapheresis and without-leukapheresis groups and resulted in 22 matched pairs of patients with AML and 16 matched pairs of patients with ALL. After matching, we observed no significant difference in early mortality rates or in the incidence of TLS or DIC between the two groups of patients with AML and ALL. CONCLUSION: Although leukapheresis may rapidly reduce white blood cell counts and leukemic blasts, any positive influence of leukapheresis could not be demonstrated by an effect on survival outcome and the incidence of early complications, such as TLS and DIC. These results suggest that a routinely performed, prophylactic leukapheresis cannot be recommended.

Retrospective analysis on the diagnostic performances and signal-to-cut-off ratios of the Elecsys Anti-HCV II assay.

BACKGROUND: Anti-HCV assays are widely used as a screening tool for HCV infection. However, diagnostic performances and effective signal-to-cut-off ratios (S/COs) for predicting true HCV infections would vary according to the assays used. Thus, we evaluated the diagnostic performances of the new Elecsys Anti-HCV assay. METHODS: A total of 41 694 cases tested by the Elecsys Anti-HCV II assay (Roche Diagnostics, Germany) during January 2013 to December 2015 were retrospectively analyzed by comparing with the diagnosis on HCV infections determined by patients' medical records and results of laboratory tests. RESULTS: Excluding 62 cases with unclear history of HCV infection, 430 and 41 202 cases were respectively assorted as "true infection" and "no evidence of infection," and 99.85% of the initial results by the Elecsys assay were concordant with the diagnosis on HCV infection. Sensitivity, specificity, positive and negative predictive values were respectively 99.30%, 99.86%, 88.04%, and 99.99%, where the prevalence of the HCV infection was 1.0%. The area under the receiver operating characteristics curve value of the Elecsys assay was 0.9980 (95% confidence interval [CI]=0.9944 to 1.0017). The S/CO by the Elecsys assay for predictive of a true-positive ≥95% of the time was 19.0 (95% CI=15.0 to 25.1). CONCLUSION: The Elecsys Anti-HCV II assay showed excellent diagnostic performances, particularly in terms of sensitivity, specificity, and NPV. However, the results obtained by this assay with S/CO less than a certain value would need to be retested by HCV RNA PCR or another anti-HCV assay.

The clinicopathological relevance of pretransplant anti-angiotensin II type 1 receptor antibodies in renal transplantation.

BACKGROUND: Anti-angiotensin II type 1 receptor antibodies (AT1R-Abs) have been suggested as a risk factor for graft failure and acute rejection (AR). However, the prevalence and clinical significance of pretransplant AT1R-Abs have seldom been evaluated in Asia. METHODS: In this multicenter, observational cohort study, we tested the AT1R-Abs in pretransplant serum samples obtained from 166 kidney transplant recipients. Statistical analysis was used to set a threshold AT1R-Abs level at 9.05 U/mL. RESULTS: Pretransplant AT1R-Abs were detected in 98/166 (59.0%) of the analyzed recipients. No graft loss or patient death was reported during the study period. AT1R-Abs (+) patients had a significantly higher incidence of biopsy-proven AR than AT1R-Abs (-) patients (27.6 versus 10.3%, P = 0.007). Recipients with pretransplant AT1R-Abs had a 3.2-fold higher risk of AR within a year of transplantation (P = 0.006). Five study subjects developed microcirculation inflammation (score ≥2). Four of them were presensitized to AT1R-Abs. In particular, three patients had a high titer of anti-AT1R-Abs (>22.7 U/mL). CONCLUSIONS: Pretransplant AT1R-Abs is an independent risk factor for AR, especially acute cellular rejection, and is possibly associated with the risk of antibody-mediated injury. Pretransplant assessment of AT1R-Abs may be useful for stratifying immunologic risks.

Comparison of Abbott RealTime genotype II, GeneMatrix restriction fragment mass polymorphism and Sysmex HISCL HCV Gr assays for hepatitis C virus genotyping.

BACKGROUND: Hepatitis C virus (HCV) genotype is a predictive marker for treatment response. We sequentially evaluated the performances of two nucleic acid amplification tests (NAATs) and one serology assay for HCV genotype: Abbott RealTime genotype II (RealTime II), GeneMatrix restriction fragment mass polymorphism (RFMP), and Sysmex HISCL HCV Gr (HISCL Gr). METHODS: We examined 281 clinical samples with three assays. The accuracy was assessed using the HCV Genotype Performance Panel PHW204 (SeraCare Life Sciences) for two NAATs. Discrepant cases were re-genotyped by the Versant HCV v.2.0 (line probe 2.0) assay. RESULTS: With the RealTime II assay, clinic samples were analyzed as follows: genotypes 1b (43.1%), 2 (40.2%), 1 subtypes other than 1a and 1b (12.5%), 3 (1.8%), 4 (1.4%), 1a (0.7%), 6 (0.4%), and mixed (1.1%). The RealTime II and RFMP assays showed a type concordance rate of 97.5% (274/281) (κ=0.80) and no significant discordance (p=0.25). Both assays accurately genotyped all samples in the Performance Panel by the subtype level. The HISCL Gr assay showed concordance rates of about 91% (κ<0.40) and statistically significant discordances with two NAATs (p<0.05). In confirmation tests, the results of RFMP assay were the most consistent with those of Versant 2.0 assay. CONCLUSIONS: The three HCV assays provided genotyping and serotyping results with good concordance rates. The two NAATs (RealTime II and RFMP) showed comparable performance and good agreement. However, the results of the HISCL Gr assay showed statistically significant differences with those of the NAATs.

A 12-month single arm pilot study to evaluate the efficacy and safety of sirolimus in combination with tacrolimus in kidney transplant recipients at high immunologic risk.

The optimal immunosuppressive strategy for renal transplant recipients at high immunologic risk remains a topic of investigation. This prospective single arm pilot study was undertaken to evaluate the safety and efficacy of a combined tacrolimus and sirolimus regimen in recipients at immunological high risk and to compare outcomes with a contemporaneous control group received tacrolimus and mycophenolate mofetil. Patients that received a renal allograft between 2010 and 2011 at high risk (defined as panel reactive antibodies > 50%, 4 or more human leukocyte antigen mismatches, or retransplantation) were enrolled. All patients received basiliximab induction and corticosteroids. A total of 28 recipients treated with tacrolimus and sirolimus were enrolled in this study and 69 recipients were retrospectively reviewed as a control group. The sirolimus group showed a higher, but not statistically significant, incidence of biopsy proven acute rejection and a lower glomerular filtration rate than the control group. Furthermore, sirolimus group was associated with significant increases in BKV infection (P = 0.031), dyslipidemia (P = 0.004), and lymphocele (P = 0.020). The study was terminated prematurely due to a high incidence of adverse events. A de novo tacrolimus/sirolimus combination regimen may not be an ideal choice for recipients at high immunological risk.

Development and validation of artificial intelligence models to predict urinary tract infections and secondary bloodstream infections in adult patients.

BACKGROUND: Traditional culture methods are time-consuming, making it difficult to utilize the results in the early stage of urinary tract infection (UTI) management, and automated urinalyses alone show insufficient performance for diagnosing UTIs. Several models have been proposed to predict urine culture positivity based on urinalysis. However, most of them have not been externally validated or consisted solely of urinalysis data obtained using one specific commercial analyzer. METHODS: A total of 259,187 patients were enrolled to develop artificial intelligence (AI) models. AI models were developed and validated for the diagnosis of UTI and urinary tract related-bloodstream infection (UT-BSI). The predictive performance of conventional urinalysis and AI algorithms were assessed by the areas under the receiver operating characteristic curve (AUROC). We also visualized feature importance rankings as Shapley additive explanation bar plots. RESULTS: In the two cohorts, the positive rates of urine culture tests were 25.2% and 30.4%, and the proportions of cases classified as UT-BSI were 1.8% and 1.6%. As a result of predicting UTI from the automated urinalysis, the AUROC were 0.745 (0.743-0.746) and 0.740 (0.737-0.743), and most AI algorithms presented excellent discriminant performance (AUROC > 0.9). In the external validation dataset, the XGBoost model achieved the best values in predicting both UTI (AUROC 0.967 [0.966-0.968]) and UT-BSI (AUROC 0.955 [0.951-0.959]). A reduced model using ten parameters was also derived. CONCLUSIONS: We found that AI models can improve the early prediction of urine culture positivity and UT-BSI by combining automated urinalysis with other clinical information. Clinical utilization of the model can reduce the risk of delayed antimicrobial therapy in patients with nonspecific symptoms of UTI and classify patients with UT-BSI who require further treatment and close monitoring.

Performance evaluation of LUMIPULSE G1200 autoimmunoanalyzer for the detection of serum hepatitis B virus markers.

BACKGROUND: We evaluated recently introduced automated immunoassay analyzer LUMIPULSE G1200 (Fujirebio, Inc., Tokyo, Japan) for detecting serologic hepatitis B virus (HBV) markers by comparison with the results by ARCHITECT i4000SR (Abbott, Abbott Park, IL). METHODS: Precision performance was evaluated over 20 days. HBV surface antigen (HBsAg), HBV e antigen (HBeAg), antibodies to HBV core antigen (anti-HBc), antibodies to HBeAg (anti-HBe), and antibodies to HBsAg (anti-HBs) in a total of 1,000 serum samples were assessed by the two analyzers. Discrepant results were retested by COBAS e411 (Roche Diagnostics, Mannheim, Germany). RESULTS: LUMIPULSE showed excellent precision performance of total imprecision less than 3.5% coefficient of variation. The qualitative results between the two analyzers were agreed with each other in 92.0-99.8% of the specimens according to the different HBV markers. The degrees of reactions for HBeAg were moderately correlated between the two analyzers (r = 0.60), and those of other HBV markers were well correlated (r = 0.80 or greater). However, there were 183 discrepancies among 1,000 cases, and most of them showed degree of reaction around the cutoff values. CONCLUSIONS: LUMIPULSE G1200 showed well-concordant results with ARCITHECT for hepatitis B serologic tests. However, results near the cutoff values would need to be retested with other immunoassay or molecular methods, when the serological profiles of HBV markers are unusual or are not correlated to the clinical conditions of the patient, due to discrepancies between the immunoassay analyzers.

Muscle mass has a greater impact on serum creatinine levels in older males than in females.

Background and aims: We analyzed the effects of age and sex on the relationship between muscle mass and serum creatinine levels in an apparently healthy population, including older adults. Materials and methods: We retrospectively evaluated 1,502 individuals from the Korea National Health and Nutrition Examination Survey (KNHANES) and 4,586 individuals from the Health Check (HC) groups. We utilized data from the KNHANES and HC groups on serum creatinine levels and skeletal muscle mass index (SMI), determined using dual X-ray absorptiometry or bioelectric impedance analysis. Results: A significant negative correlation between SMI and age was observed in both the KNHANES and HC groups in males but not in females. In males, serum creatinine levels showed a significant negative correlation with age in both the KNHANES (r = -0.522, P < 0.0001) and HC groups (r = -0.451, P < 0.0001). In females, there was no significant correlation between serum creatinine levels and age in the KNHANES (r = -0.016, P = 0.5985) and HC group (r = -0.011, P = 0.5618). Conclusions: Serum creatinine levels decrease more significantly in older males than in older females due to sex-specific muscle mass decline.

A single-center experience on long-term clinical performance of a rapid SARS-CoV-2 Antigen Detection Test, STANDARD Q COVID-19 Ag Test.

The COVID-19 pandemic in Korea has dynamically changed with the occurrence of more easily transmissible variants. A rapid and reliable diagnostic tool for detection of SARS-CoV-2 is needed. While RT-PCR is currently the gold standard for detecting SARS-CoV-2, the procedure is time-consuming and requires expert technicians. The rapid antigen detection test (RADT) was approved as a confirmatory test on 14 March 2022 due to rapid dissemination of the Omicron variant. The benefits of the RADT are speed, simplicity, and point-of-care feasibility. The aim of our study was to evaluate the clinical performance of RADT compared to RT-PCR in a single center over 15 months, fully covering the SARS-CoV-2 'Variants of Concern (VOC).' A total of 14,194 cases was simultaneously tested by RT-PCR and RADT from January 2021 to March 2022 in Gangnam Severance Hospital and were retrospectively reviewed. PowerChek SARS-CoV-2, Influenza A&B Multiplex Real-time PCR Kit, and STANDARD Q COVID-19 Ag Test were used. Positive rates, sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) were estimated for five periods (3 months/period). Receiver operator characteristic curve (ROC) analysis was performed, and Spearman's rank test assessed the correlation between RT-PCR Ct values and semi-quantitative RADT results. The overall positive rate of RT-PCR was 4.64%. The overall sensitivity and specificity were 0.577 [95% confidence interval (CI) 0.539-0.614] and 0.991 [95% CI 0.989-0.993], respectively. ROC analysis resulted in an area under the curve of 0.786 (P < 0.0001, Yuden's index = 0.568). The PCR positive rates were estimated as 0.11%, 0.71%, 4.51%, 2.02%, and 13.72%, and PPV was estimated as 0.045, 0.421, 0.951, 0.720, and 0.798 in Periods 1, 2, 3, 4, and 5, respectively. A significant and moderate negative correlation between PCR Ct values and semi-quantitative RADT results was observed (Spearman's ρ = - 0.646, P < 0.0001). The RADT exhibited good performance in specimens with low Ct values (Ct ≤ 25.00) by RT-PCR. The PPV was significantly higher in Periods 3 and 5, which corresponds to rapid dissemination of the Delta and Omicron variants. The high PPV implies that individuals with a positive RADT result are very likely infected with SARS-CoV-2 and would require prompt quarantine rather than additional RT-PCR testing. The sensitivity of 0.577 indicates that RADT should not replace RT-PCR. Nonetheless, given the high PPV and the ability to track infected persons through rapid results, our findings suggest that RADT could play a significant role in control strategies for further SARS-CoV-2 variants.

Calf Circumference as an Indicator for Cystatin C Testing in Hospitalized Elderly Male Patients for Detecting Hidden Renal Impairment.

Serum creatinine is used to measure the estimated glomerular filtration rate (eGFR); however, it is influenced by muscle mass and may therefore overestimate renal function in patients with sarcopenia. We examined calf circumference (CC) as a convenient muscle mass evaluation tool that can potentially indicate the need to test for cystatin C instead of creatinine in elderly inpatients. We retrospectively reviewed the electronic health record of 271 inpatients aged 65 or over. CC was determined by measuring the thickest part of the nondominant calf. eGFRcys and eGFRcr were calculated using cystatin C and creatinine levels, respectively. We evaluated optimum CC cutoff values using the eGFRcys/eGFRcr ratio for detecting hidden renal impairment (HRI, defined as eGFRcr ≥ 60 mL/min/1.73 m2 but eGFRcys < 60 mL/min/1.73 m2). CC showed a significant positive correlation with the eGFRcys/eGFRcr ratio in both sexes. The areas under the receiver operating characteristic curve were 0.725 and 0.681 for males and females, respectively. CC cutoffs with a sensitivity or specificity of 90% or 95% might be used to detect HRI in males. In conclusion, utilizing the optimum cutoff, CC could be a cost-effective screening tool for detecting HRI in elderly male patients using cystatin C as an add-on test.

Reference ranges for HE4 and CA125 in a large Asian population by automated assays and diagnostic performances for ovarian cancer.

Human epididymis protein 4 (HE4) is a new biomarker for the detection of ovarian cancer. We evaluated the analytical performance of a novel automated HE4 assay and established reference ranges of HE4 and CA125. We also compared the diagnostic performance of both biomarkers for ovarian cancer. Precision performances and linearity of the HE4 assay were assessed. Serum samples from 2,182 healthy and 72 pregnant women were also assayed for HE4 and CA125, and the 95%, 97.5% and 99% reference limits for both markers were calculated. Additionally, sera from 66 ovarian cancer and 257 benign gynecologic disease patients were tested to validate reference ranges and diagnostic performances. The total precision of the HE4 assay was <5% coefficient of variation for most of the levels evaluated. The linearity range of this assay was from 15.0 to 1100.0 pmol/L. The 97.5% upper reference limits for HE4 and CA125 were 33.2 pmol/L (95% confidence interval [CI], 32.2-34.0) and 38.3 U/mL (95% CI, 35.1-41.5), respectively. Using these values as cutoff points, the sensitivity and specificity of HE4 for differentiating ovarian cancer from benign gynecologic diseases and healthy individuals were 90.9% and 94.1%, and those of CA125 were 72.7% and 94.4%. The receiver operating characteristic-area under the curve values of HE4 and CA125 for discriminating ovarian cancer from age-matched control were 0.94 and 0.86, respectively, and they were statistically different (p = 0.0095). The new automated HE4 assay showed good analytical and diagnostic performances. The reference limits established in our study could be used as cutoff levels to facilitate more accurate diagnosis of ovarian cancer in Asian population.

Comparison of the Abbott RealTime High-Risk Human Papillomavirus (HPV), Roche Cobas HPV, and Hybrid Capture 2 assays to direct sequencing and genotyping of HPV DNA.

Infection with high-risk (HR) human papillomavirus (HPV) genotypes is an important risk factor for cervical cancers. We evaluated the clinical performances of two new real-time PCR assays for detecting HR HPVs compared to that of the Hybrid Capture 2 test (HC2). A total of 356 cervical swab specimens, which had been examined for cervical cytology, were assayed by Abbott RealTime HR and Roche Cobas HPV as well as HC2. Sensitivities and specificities of these assays were determined based on the criteria that concordant results among the three assays were regarded as true-positive or -negative and that the results of genotyping and sequencing were considered true findings when the HPV assays presented discrepant results. The overall concordance rate among the results for the three assays was 82.6%, and RealTime HR and Cobas HPV assays agreed with HC2 in 86.1% and 89.9% of cases, respectively. The two real-time PCR assays agreed with each other for 89.6% of the samples, and the concordance rate between them was equal to or greater than 98.0% for detecting HPV type 16 or 18. HC2 demonstrated a sensitivity of 96.6% with a specificity of 89.1% for detecting HR HPVs, while RealTime HR presented a sensitivity of 78.3% with a specificity of 99.2%. The sensitivity and specificity of Cobas HPV for detecting HR HPVs were 91.7% and 97.0%. The new real-time PCR assays exhibited lower sensitivities for detecting HR HPVs than that of HC2. Nevertheless, the newly introduced assays have an advantage of simultaneously identifying HPV types 16 and 18 from clinical samples.

Serum neutrophil gelatinase-associated lipocalin and interleukin-18 as predictive biomarkers for delayed graft function after kidney transplantation.

BACKGROUND: Early biomarkers for acute kidney injury after kidney transplantation have been studied because delayed graft function (DGF) is associated with increased risk of acute rejection and graft loss. We investigated the usefulness of serum neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-18 (IL-18) for the prediction of DGF after kidney transplantation. MATERIALS AND METHODS: Fifty-nine kidney transplant recipients were included and they were separated into DGF and immediate graft function (IGF) groups. Serum samples were collected on the preoperative day as well as days 1, 5, and 14 after the transplantation, and assayed for NGAL and IL-18. RESULTS: After transplantation, serum levels of NGAL were significantly higher at any time in patients with DGF compared to those with IGF. Serum concentrations of IL-18 were not different between both groups. The receiver operating characteristics(ROC)-area under the curve (AUC) values of NGAL, IL-18, and creatinine on day 1 for the discrimination of DGF from IGF were 0.86, 0.63, and 0.65. On POD1, the sensitivities of NGAL and creatinine were respectively 78.6%, and 50.0% at 77.8% specificity, and the AUC values for any combinations including NGAL and that for NGAL alone were higher than that of creatinine. CONCLUSION: Serum NGAL is an early and sensitive marker of graft dysfunction in kidney transplantation, while serum IL-18 showed limited values.

Serum cytokine levels in chronic hepatitis B patients receiving peginterferon alpha-2a therapy.

BACKGROUND: The relationship between cytokines and responses to peginterferon alpha-2a treatment in chronic hepatitis B patients has not yet been fully elucidated. We analyzed the serum levels of interleukin (IL)-1alpha, IL-1beta, IL-2, IL-4, IL-6, IL-8, IL-10, vascular endothelial growth factor, interferon-gamma, tumor necrosis factor-alpha, monocyte chemotactic protein-1 (MCP1) and epidermal growth factor during the treatment with peginterferon alpha-2a. METHODS: Ninety-three serum samples from 20 chronic hepatitis B patients were collected before, during and after 48 weeks of peginterferon therapy and were assayed for 12 cytokines. The patients were categorized as either virologic responders (VRs) or non-responders (NRs) according to their HBV DNA levels taken at 6th month during treatment. The Evidence Investigator (Randox, Antrim, UK), a protein chip analyzer, was used to quantify cytokines. RESULTS: Among the 12 cytokines, the levels of MCP1 were increased and the levels of IL-4 were decreased during the treatment in VRs. However these cytokines were not significantly changed in NRs in the treatment phases. Area under the receiver operating characteristic curve (AUROC) value of HBV DNA measured before the treatment was 0.81 in predicting VRs, and that of the baseline MCP1 was 0.76. IL-6 levels at 3rd and 6th months during the treatment also showed AUROC values 0.85 and 0.78 respectively in predicting sustained VRs. CONCLUSION: Serum cytokine levels reflect the pathological differences of individual treatment phases and could also be useful in monitoring responses to peginterferon treatment in chronic hepatitis B patients.

Impact of urinary tract infection-causative microorganisms on the progression to bloodstream infection: A propensity score-matched analysis.

OBJECTIVES: We aimed to determine the risk factors for the progression of urinary tract infection (UTI) to bloodstream infection (BSI) and to evaluate the mortality-associated factors in patients with urinary tract-related BSI (UT-BSI). METHODS: A propensity score-matched study was conducted using clinical data from all adult patients with UTIs in two South Korean hospitals. RESULTS: A total of 84,406 patients with UTIs were enrolled. The relative incidence of UTIs caused by Escherichia coli decreased along with an increase in the incidence of Candida species infections during the study period. UTI caused by E. coli, Klebsiella pneumoniae, Staphylococcus aureus, and Candida species had a relatively high rate of progression to BSI. UT-BSI caused by Candida species (adjusted odd ratio 5.67; 95% confidence interval 3.97-8.11; p < 0.001) was significantly associated with high 30-day mortality. CONCLUSIONS: UTI-causative microorganisms were associated with both progression to UT-BSI and 30-day mortality in patients with UT-BSI. Considering the trend of increasing age of patients and more frequent use of indwelling urologic devices, UT-BSIs caused by other microorganisms than E. coli could be a more serious medical burden in the future.