Laboratory Preparation for Digital Medicine in Healthcare 4.0: An Investigation Into the Awareness and Applications of Big Data and Artificial Intelligence.

Background: Healthcare 4.0. refers to the integration of advanced technologies, such as artificial intelligence (AI) and big data analysis, into the healthcare sector. Recognizing the impact of Healthcare 4.0 technologies in laboratory medicine (LM), we seek to assess the overall awareness and implementation of Healthcare 4.0 among members of the Korean Society for Laboratory Medicine (KSLM). Methods: A web-based survey was conducted using an anonymous questionnaire. The survey comprised 36 questions covering demographic information (seven questions), big data (10 questions), and AI (19 questions). Results: In total, 182 (17.9%) of 1,017 KSLM members participated in the survey. Thirty-two percent of respondents considered AI to be the most important technology in LM in the era of Healthcare 4.0, closely followed by 31% who favored big data. Approximately 80% of respondents were familiar with big data but had not conducted research using it, and 71% were willing to participate in future big data research conducted by the KSLM. Respondents viewed AI as the most valuable tool in molecular genetics within various divisions. More than half of the respondents were open to the notion of using AI as assistance rather than a complete replacement for their roles. Conclusions: This survey highlighted KSLM members' awareness of the potential applications and implications of big data and AI. We emphasize the complexity of AI integration in healthcare, citing technical and ethical challenges leading to diverse opinions on its impact on employment and training. This highlights the need for a holistic approach to adopting new technologies.

Delta check limits for thyroid function tests adjusted for clinical settings.

BACKGROUND: This study aimed to determine practical delta check limits (DCLs) for thyroid function tests (TFTs) to detect sample misidentifications across various clinical settings. METHODS: Between 2020 and 2022, 610,437 paired TFT results were collected from six university hospitals. The absolute DCL (absDCL) was determined using the 95th percentile for each clinical setting from a random 60 % of the total data. These absDCLs were then tested within and across different settings using the remaining 40 % of the data, alongside mix-up datasets for result and sample comparisons. The sensitivities of absDCL were calculated within and across groups in the mix-up datasets. RESULTS: Health screening absDCLs were notably lower than in other settings (2.58 vs. 5.93-7.08 for thyroid-stimulating hormone; 4.12 vs. 8.24-10.04 for free thyroxine; 0.49 vs. 0.82-0.91 for total triiodothyronine). The proportion of results exceeding absDCL of health screening differed from those of other clinical settings. Furthermore, sensitivity between health screening and other clinical settings was significantly different in both the result mix-up and sample mix-up datasets. CONCLUSIONS: This study determined practical DCLs for TFTs and highlighted differences in absDCLs between health screening and other settings. These findings emphasize the importance of tailored DCLs in improving the accurate reporting of TFTs.

Machine learning-based delta check method for detecting misidentification errors in tumor marker tests.

OBJECTIVES: Misidentification errors in tumor marker tests can lead to serious diagnostic and treatment errors. This study aims to develop a method for detecting these errors using a machine learning (ML)-based delta check approach, overcoming limitations of conventional methods. METHODS: We analyzed five tumor marker test results: alpha-fetoprotein (AFP), cancer antigen 19-9 (CA19-9), cancer antigen 125 (CA125), carcinoembryonic antigen (CEA), and prostate-specific antigen (PSA). A total of 246,261 records were used in the analysis. Of these, 179,929 records were used for model training and 66,332 records for performance evaluation. We developed a misidentification error detection model based on the random forest (RF) and deep neural network (DNN) methods. We performed an in silico simulation with 1 % random sample shuffling. The performance of the developed models was evaluated and compared to conventional delta check methods such as delta percent change (DPC), absolute DPC (absDPC), and reference change values (RCV). RESULTS: The DNN model outperformed the RF, DPC, absDPC, and RCV methods in detecting sample misidentification errors. It achieved balanced accuracies of 0.828, 0.842, 0.792, 0.818, and 0.833 for AFP, CA19-9, CA125, CEA, and PSA, respectively. Although the RF method performed better than DPC and absDPC, it showed similar or lower performance compared to RCV. CONCLUSIONS: Our research results demonstrate that an ML-based delta check method can more effectively detect sample misidentification errors compared to conventional delta check methods. In particular, the DNN model demonstrated superior and stable detection performance compared to the RF, DPC, absDPC, and RCV methods.

Practical delta check limits for tumour markers in different clinical settings.

OBJECTIVES: Few studies have reported on delta checks for tumour markers, even though these markers are often evaluated serially. Therefore, this study aimed to establish a practical delta check limit in different clinical settings for five tumour markers: alpha-fetoprotein, cancer antigen 19-9, cancer antigen 125, carcinoembryonic antigen, and prostate-specific antigen. METHODS: Pairs of patients' results (current and previous) for five tumour markers between 2020 and 2021 were retrospectively collected from three university hospitals. The data were classified into three subgroups, namely: health check-up recipient (subgroup H), outpatient (subgroup O), and inpatient (subgroup I) clinics. The check limits of delta percent change (DPC), absolute DPC (absDPC), and reference change value (RCV) for each test were determined using the development set (the first 18 months, n=179,929) and then validated and simulated by applying the validation set (the last 6 months, n=66,332). RESULTS: The check limits of DPC and absDPC for most tests varied significantly among the subgroups. Likewise, the proportions of samples requiring further evaluation, calculated by excluding samples with both current and previous results within the reference intervals, were 0.2-2.9% (lower limit of DPC), 0.2-2.7% (upper limit of DPC), 0.3-5.6% (absDPC), and 0.8-35.3% (RCV99.9%). Furthermore, high negative predictive values >0.99 were observed in all subgroups in the in silico simulation. CONCLUSIONS: Using real-world data, we found that DPC was the most appropriate delta-check method for tumour markers. Moreover, Delta-check limits for tumour markers should be applied based on clinical settings.

Humoral response to vaccination against SARS-CoV-2 in patients undergoing dialysis.

Patients undergoing maintenance dialysis have a higher mortality rate associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and response rates to vaccination against SARS-CoV-2 vary from 29.6% to 96.4% in such patients. This study aimed to assess the immunogenicity of SARS-CoV-2 vaccination in Korean patients undergoing dialysis. We enrolled 70 SARS-CoV-2-vaccinated patients undergoing dialysis, with 11 healthcare workers serving as healthy control subjects. Thirty-two patients had received a third vaccination, whereas 38 had received 2 vaccinations. The healthy control subjects completed the second vaccination. Immunoglobulin G (IgG) antibodies targeting the receptor-binding domain of the S1 subunit of the SARS-CoV-2 spike protein were measured The vaccination responder rates were 86% (37/43), 96% (26/27), and 91% (10/11) in the patients undergoing hemodialysis and peritoneal dialysis and healthy controls, respectively. IgG antibody levels were significantly higher when a third dose was administered, independent of the type of vaccine or the time interval between vaccination and the subsequent blood sampling date. When a third dose of vaccine was administered, there was no difference in IgG antibody levels between those receiving cross-vaccination or a single vaccine. There was no significant difference in IgG antibodies between healthy controls and patients undergoing dialysis. Patients on dialysis exhibited a sufficient antibody-related response to vaccination against SARS-CoV-2, even in those receiving cross-vaccination, and the antibody titer was higher after a third vaccination. Therefore, it is necessary to administer a third vaccine dose to Korean patients undergoing dialysis.

Immunosuppressant and SARS-CoV-2 Vaccine Antibody Response After Lung Transplantation.

BACKGROUND: There are insufficient reports on the immunogenicity and safety of the COVID-19 vaccination after lung transplantation in Korea. METHODS: Between April and September 2021, lung transplant recipients (n = 52) and healthy controls (n = 22) underwent vaccination. The levels of antibodies were assessed prospectively at 4 weeks after priming and second dose. RESULTS: Of a total of 52 lung transplant recipients, there were 84.6% nonresponders, 15.4% second-dose responders, and 0% primary dose responders. Among healthy controls, 63.6% were priming responders, and 18.2% were second-dose responders, and 18.2% were nonresponders. Compared with the control group, lung recipients were less likely to develop antibodies (P < .001). Antibody formation tended to be higher in recipients more than 1 year after transplantation (0 vs 20.5%, P = .076). No major safety events were reported, and the adverse symptoms were mild and consistent with those of the general population. In a multivariate regression analysis, mycophenolic acid levels (µg/mL) (odds ratio 0.25, P = .005) and tacrolimus level (ng/mL) (odds ratio 0.65, P = .035) were significantly associated with antibody formation. CONCLUSIONS: The immunogenicity of the second dose of COVID-19 vaccination with various combinations was substantially low in lung transplants. A booster of the COVID-19 vaccine is warranted in lung transplants, especially a year later.

Impacts of Side Effects to BNT162b2 and the First Dose of ChAdOx1 Anti-SARS-CoV-2 Vaccination on Work Productivity, the Need for Medical Attention, and Vaccine Acceptance: A Multicenter Survey on Healthcare Workers in Referral Teaching Hospitals in the Republic of Korea.

To establish a successful anti-SARS-CoV-2 vaccination strategy, it is necessary to take possible tradeoffs into account. We conducted a survey on vaccinated healthcare workers (HCWs) inthree referral teaching hospitals in the Republic of Korea. We investigated the frequency of vaccination side effects (SEs), the impact on their work productivity, the need for medical attention, and vaccine acceptance. Three groups of HCWs were surveyed: 1406 who had received the first dose of BNT162b2 (BNT162b2#1), 1168 who had received the second dose of BNT162b2 (BNT162b2#2), and 1679 who had received the first dose of ChAdOx1 (ChAdOx1#1). More SEs and impact on work productivity were reported in ChAdOx1#1 than in the other two groups. However, among individuals aged ≥40 years, no significant difference of absence from work was found between ChAdOx1#1 and BN162b2#2 (4.4%, 31/699 vs. 3.0%, 12/405; p = 0.26), and none were hospitalized. Older HCWs in ChAdOx1#1 showed intention to receive the second dose of the vaccine. Although the incidence of SEs and their impacts were greater after the first dose of ChAdOx1 than BNT162b2 in young people, significant impact of SEs seemed to be rare in individuals aged ≥40 years, regardless of the vaccine they received.

Risk factors for isolation of multi-drug resistant organisms in coronavirus disease 2019 pneumonia: A multicenter study.

OBJECTIVES: Superimposed multi-drug resistant organisms (MDROs) co-infection can be associated with worse outcomes in patients with severe coronavirus disease 2019 (COVID-19), even if these patients were managed with strict airborne and contact precautions. Identifying risk factors for isolation of MDROs is critical to COVID-19 treatment. METHODS: All eligible adult patients with confirmed COVID-19 pneumonia from 10 hospitals in the Republic of Korea between February 2020 and May 2020 were retrospectively enrolled. Using this cohort, epidemiology and risk factors for isolation of MDROs were evaluated. RESULTS: Of 152 patients, 47 with microbial culture results were included. Twenty isolates of MDROs from 13 (28%) patients were cultured. Stenotrophomonas maltophilia (5 isolates) was the most common MDRO, followed by methicillin-resistant staphylococcus aureus (4 isolates). MDROs were mostly isolated from sputum samples (80%, 16/20). The median time from hospitalization to MDRO isolation was 28 days (interquartile range, 18-38 days). In-hospital mortality was higher in patients with MDRO isolation (62% vs 15%; P = .001). Use of systemic corticosteroids after diagnosis of COVID-19 (adjusted odds ratio [aOR]: 15.07; 95% confidence interval [CI]: 2.34-97.01; P = .004) and long-term care facility (LTCF) stay before diagnosis of COVID-19 (aOR: 6.09; 95% CI: 1.02-36.49; P = .048) were associated with MDRO isolation. CONCLUSIONS: MDROs were isolated from 28% of COVID-19 pneumonia patients with culture data and 8.6% of the entire cohort. Previous LTCF stay and adjunctive corticosteroid use were risk factors for the isolation of MDROs. Strict infection prevention strategies may be needed in these COVID-19 patients with risk factors.

Compound Heterozygous PIGT Mutations in Multiple Congenital Anomalies-Hypotonia-Seizures Syndrome: First Case in Korea and Characterization by Persistent Hypophosphatasia.

Mutations of phosphatidylinositol glycan biosynthesis class T (PIGT), which encodes a subunit of the glycosylphosphatidylinositol (GPI) transamidase complex, can lead to multiple anomalies, including seizures, intellectual disabilities, facial dysmorphism, and various congenital malformations. We performed whole-exome sequencing in a patient with seizures, intellectual disabilities, truncal ataxia, facial dysmorphism, and persistent hypophosphatasia without rickets or bone mineralization defects, and identified two heterozygous mutations in PIGT, c.250G>T (p.Glu84*) and c.1582G>A (p.Val528Met). GPI-linked protein analyses found no abnormalities. Although the patient's hypophosphatasia persists, no skeletal, urological, or dental abnormalities were found. The seizures disappeared after administering antiepileptic drugs. PIGT mutations should be considered in patients with multiple congenital symptoms and persistent hypophosphatasia.

Promotion of healthcare personnel vaccinations among newly employed doctors and nurses: Evidence-guided strategy.

OBJECTIVE: Healthcare personnel vaccinations are important to prevent vaccine-preventable diseases in hospitals. We evaluated the seroprevalence, vaccination rates, and barriers to vaccination among newly employed nurses and doctors. METHODS: A cross-sectional study was conducted at a university hospital in the Republic of Korea from 2017 to 2020. The immune status for hepatitis B virus (HBV), varicella zoster virus (VZV), and hepatitis A virus (HAV) was tested. HBV, VZV, measles, mumps, and rubella (MMR) vaccinations were mandatory. HAV and tetanus-diphtheria-pertussis (Tdap) vaccinations were also recommended by specialists. A web-based survey on factors affecting vaccination completion was conducted. RESULTS: For the 668 participants, the mean age was 26 ± 2 (±SD) years. Seroprevalence was 86% for HBV, 93% for VZV, and 59% for HAV. Vaccine completion rates were 40% for HBV, 70% for VZV, 65% for MMR, 42% for HAV, and 70% for Tdap. Overall compliance for mandatory vaccines was 54%. A total of 402 subjects who had worked for over one year were surveyed, with a 22% response rate. More than 50% of respondents gave the following reasons for not receiving recommend vaccines: 1) they were busy (77%), 2) vaccination process was complicated (68%), and 3) they simply forgot about vaccination (55%). Healthcare personnel agreed to be frequently informed of immunization requirements and for monitoring of vaccination rates. CONCLUSION: Vaccination compliance among newly employed doctors and nurses was 54%. Active interventions such as simplifying the vaccination process and frequent notifications are needed to achieve optimal immunization rates.

Clinical Course and Molecular Viral Shedding Among Asymptomatic and Symptomatic Patients With SARS-CoV-2 Infection in a Community Treatment Center in the Republic of Korea.

IMPORTANCE: There is limited information about the clinical course and viral load in asymptomatic patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). OBJECTIVE: To quantitatively describe SARS-CoV-2 molecular viral shedding in asymptomatic and symptomatic patients. DESIGN, SETTING, AND PARTICIPANTS: A retrospective evaluation was conducted for a cohort of 303 symptomatic and asymptomatic patients with SARS-CoV-2 infection between March 6 and March 26, 2020. Participants were isolated in a community treatment center in Cheonan, Republic of Korea. MAIN OUTCOMES AND MEASURES: Epidemiologic, demographic, and laboratory data were collected and analyzed. Attending health care personnel carefully identified patients' symptoms during isolation. The decision to release an individual from isolation was based on the results of reverse transcription-polymerase chain reaction (RT-PCR) assay from upper respiratory tract specimens (nasopharynx and oropharynx swab) and lower respiratory tract specimens (sputum) for SARS-CoV-2. This testing was performed on days 8, 9, 15, and 16 of isolation. On days 10, 17, 18, and 19, RT-PCR assays from the upper or lower respiratory tract were performed at physician discretion. Cycle threshold (Ct) values in RT-PCR for SARS-CoV-2 detection were determined in both asymptomatic and symptomatic patients. RESULTS: Of the 303 patients with SARS-CoV-2 infection, the median (interquartile range) age was 25 (22-36) years, and 201 (66.3%) were women. Only 12 (3.9%) patients had comorbidities (10 had hypertension, 1 had cancer, and 1 had asthma). Among the 303 patients with SARS-CoV-2 infection, 193 (63.7%) were symptomatic at the time of isolation. Of the 110 (36.3%) asymptomatic patients, 21 (19.1%) developed symptoms during isolation. The median (interquartile range) interval of time from detection of SARS-CoV-2 to symptom onset in presymptomatic patients was 15 (13-20) days. The proportions of participants with a negative conversion at day 14 and day 21 from diagnosis were 33.7% and 75.2%, respectively, in asymptomatic patients and 29.6% and 69.9%, respectively, in symptomatic patients (including presymptomatic patients). The median (SE) time from diagnosis to the first negative conversion was 17 (1.07) days for asymptomatic patients and 19.5 (0.63) days for symptomatic (including presymptomatic) patients (P = .07). The Ct values for the envelope (env) gene from lower respiratory tract specimens showed that viral loads in asymptomatic patients from diagnosis to discharge tended to decrease more slowly in the time interaction trend than those in symptomatic (including presymptomatic) patients (ß = -0.065 [SE, 0.023]; P = .005). CONCLUSIONS AND RELEVANCE: In this cohort study of symptomatic and asymptomatic patients with SARS-CoV-2 infection who were isolated in a community treatment center in Cheonan, Republic of Korea, the Ct values in asymptomatic patients were similar to those in symptomatic patients. Isolation of asymptomatic patients may be necessary to control the spread of SARS-CoV-2.

Pre-Transplant Angiotensin II Type 1 Receptor Antibodies and Anti-Endothelial Cell Antibodies Predict Graft Function and Allograft Rejection in a Low-Risk Kidney Transplantation Setting.

BACKGROUND: Non-HLA antibodies, anti-angiotensin II type 1 receptor antibodies (anti-AT1R) and anti-endothelial cell antibodies (AECA), are known to play a role in allograft rejection. We evaluated the role of both antibodies in predicting post-transplant outcomes in low-risk living donor kidney transplantation (LDKT) recipients. METHODS: In 94 consecutive LDKT recipients who were ABO compatible and negative for pre-transplant HLA donor-specific antibodies, we determined the levels of anti-AT1Rs using an enzyme-linked immunosorbent assay and the presence of AECAs using a flow cytometric endothelial cell crossmatch (ECXM) assay with pre-transplant sera. Hazard ratio (HR) was calculated to predict post-transplant outcomes. RESULTS: Pre-transplant anti-AT1Rs (≥11.5 U/mL) and AECAs were observed in 36 (38.3%) and 22 recipients (23.4%), respectively; 11 recipients had both. Pre-transplant anti-AT1Rs were a significant risk factor for the development of acute rejection (AR) (HR 2.09; P=0.018), while a positive AECA status was associated with AR or microvascular inflammation only (HR 2.47; P=0.004) throughout the follow-up period. In particular, AECA (+) recipients with ≥11.5 U/mL anti-AT1Rs exhibited a significant effect on creatinine and estimated glomerular filtration rate (P<0.001; P=0.028), although the risk of AR was not significant. CONCLUSIONS: Pre-transplant anti-AT1Rs and AECAs have independent negative effects on post-transplant outcomes in low-risk LDKT recipients. Assessment of both antibodies would be helpful in stratifying the pre-transplant immunological risk, even in low-risk LDKT recipients.

Identification of a novel HLA-DQB1*05 variant allele, HLA-DQB1*05:247 by next-generation sequencing.

The new allele, HLA-DQB1*05:247 differs from HLA-DQB1*05:02:01:01 by one nucleotide substitution at codon 35.

Identification of a novel HLA-B*40 variant allele, B*40:405 by next-generation sequencing.

The new allele, HLA-B*40:405 differs from B*40:02:01:01 by one nucleotide substitution at codon 304.

Case Report of Kidney Paired Donation (KPD) with Desensitization: the Strategy and Experience of 3-Way KPD in Samsung Medical Center.

As the need for the organ donation increases, strategies to increase kidney transplantation (KT) through expanded living donation have become essential. These include kidney paired donation (KPD) programs and desensitization in incompatible transplantations. KPD enables kidney transplant candidates with incompatible living donors to join a registry with other incompatible pairs in order to find potentially compatible living donor. Positive cross match and ABO incompatible transplantation has been successfully accomplished in selective cases with several pre-conditionings. Patients who are both difficult-to-match due to broad sensitization and hard-to-desensitize because of donor conditions can often be successfully transplanted through a combination of KPD and desensitization. According to the existing data, KPD can increase the number of KTs from living donors with excellent clinical results. This is also a cost-effective treatment as compared with dialysis and desensitization protocols. We carried out 3-way KPD transplantation with one highly sensitized, positive cross match pair and with two ABO incompatible pairs. Herein we report our first successful 3-way KPD transplantation in a single center. To maximize donor-recipient matching and minimize immunologic risk, KPD programs should use proper algorithms with desensitization to identify optimal donor with simultaneous two-, three- or more complex multi-way exchanges.

Comparison of AdvanSure HPV GenoBlot and Hybrid Capture 2 assays for detection of HPV infection.

BACKGROUND: We sought to compare the performance of the AdvanSure assay to the Hybrid Capture (HC) 2 for the detection of high-risk human papillomavirus (HR HPV). METHODS: A total of 855 cervical swab specimens were obtained. We submitted all specimens for HR HPV detection with HC2 and the AdvanSure assay. We subsequently analyzed discordant results and specimens that were positive on both assays using restriction fragment mass polymorphism (RFMP) genotyping analysis. RESULTS: HC2 yielded positive results in 12.0% of specimens, while the AdvanSure assay detected one of 13 HR HPV types in 11.5% of specimens. The overall agreement rate between the assays was 98.5% with a kappa coefficient of 0.928. Discordant results between these two assays were observed in 12 cases, seven were positive only on HC2 and five were positive only on AdvanSure. RFMP analysis of the 12 discordant cases revealed three false-positive results using HC2, and one false-positive and five false-negative results using AdvanSure. CONCLUSIONS: Considering the high agreement rate with HC2 and the ability to differentiate 35 HPV genotypes including HPV 16/18, the AdvanSure assay could be used as a laboratory testing method for HPV infection screening.