Clinical laboratories are required to notify clinicians of critical laboratory levels and abnormal findings that affect patients’ prognoses. However, the immediate release of critical results of electroencephalography (EEG) depends on each laboratory, and little has been reported on this issue by clinical laboratories. We established the criteria for critical results of EEG when we satisfied the requirements for ISO 15189 (International Organization for Standardization Clinical Laboratories - Requirements for Quality and Competence). We immediately released 143 critical results of EEG from April 2015 to March 2022 at our hospital. The frequency of the immediate release of critical results was higher for patients with EEG performed in the ward than in the laboratory where many outpatients were included. Nonconvulsive status epilepticus (NCSE) and convulsive status epilepticus accounted for more than half of the cases with the immediate release of critical results, and the departments that had those results were the Advanced Critical Care and Emergency Center, Department of Neurology, and Cardiovascular Center, in which critically ill patients were admitted. Among 56 patients with NCSE, although the consciousness level had improved in 21 patients, 12 patients died and 23 showed no improvement in their consciousness level. Additionally, some patients were able to maintain their quality of life because we immediately reported the condition of the patients or their EEG results, which doctors did not expect, on the basis of our criteria of critical results. According to our investigation, the immediate release of critical results from EEG technicians may enable early treatment intervention and contribute to improving neurological prognosis.

Symptoms of transthyretin amyloid cardiomyopathy (ATTR-CM) has been known to develop peripheral neuropathy, such as carpal tunnel syndrome (CTS), earlier than cardiac. In this study, we investigated whether nerve ultrasound is useful in the diagnosis of ATTR-CM. Among 18 cases suspected of ATTR-CM at our institution, we used nerve ultrasound to compare the median nerve cross-sectional area (CSA) at the wrist and forearm, the wrist-to-forearm median nerve CSA ratio (WFR), and transthoracic echocardiographic (TTE) findings indicative of cardiac amyloidosis (CA), between 11 patients in the ATTR-CM group and 7 patients in the non-ATTR-CM group. ATTR-CM group had a significantly larger CSA at the wrist (18.0 mm² (IQR: 16.0–20.8) vs 10.0 mm² (10.0–11.0); p < 0.001) and a higher WFR (2.24 (IQR: 2.00–2.42) vs 1.16 (1.03–1.26) ; p < 0.001) compared to non ATTR-CM group, but the difference was not significant at the forearm (p = 0.457). The frequency of TTE findings for CA suspicious in the ATTR-CM group was 27% in pericardial effusion, 64% in the right ventricular wall thickness, 64% in the atrial septal thickness, 36% in the E/A ≥ 2.0, and 73% in the apical sparing, whereas WFR using nerve ultrasound was shown in all patients in the ATTR-CM group. In conclusion, our study suggests that nerve ultrasound may be a useful tool for the diagnosis of ATTR-CM.

Act on Clinical Laboratory Technicians was amended by the Medical Care Act promulgated on June 14, 2017. This clarified the standards for accuracy control at medical institutions and registered health laboratories that provide specimen testing services. According to a 2017 report, more than 90% of facilities that perform biochemical testing have internal quality control (IQC). Therefore, each laboratory measures samples of known concentration for accuracy control and confirms their accuracy. When a control sample is changed to a new lot, it is usually necessary to measure the current and new lot control samples in parallel for about one month to set a new control range, which is time-consuming and costly. In this study, when a controlled sample is changed to a new lot, we devised a method to set a control width for the new lot without spending time and money. Methods and Results: (1) There was no difference in the precision of QAP trawls from different lots. (2) The Bonferroni method was used to compare monthly IQC measurements, and significant differences were found among most of the groups. (3) The CV variability was reduced by aggregating IQC measurements over 6 months. Based on the above, we believe that this method can be used at many facilities because it is relatively easy and cost-effective for facilities that have conducted IQC and accumulated IQC data to calculate the SD relative to the target value using the CV calculated from IQC measurements for a minimum of 6 months.

Periodic acid–methenamine silver (PAM) staining is often used for the histopathological examination of kidney tissues. However, this technique has low reproducibility, especially with thick sections, as the silver reaction is difficult to control. Therefore, we attempted to improve the staining technique by changing the sequence of the methenamine silver reaction, the actual conditions, and the endpoint of the method. We then examined the effects of these changes on staining quality. The typical target thickness of formalin-fixed paraffin-embedded kidney sections is 2 μm. Slides are placed in a heated silver solution and microwaved to achieve a stirring effect and shorten the reaction time. The silver reaction can be easily controlled at 45°C, although the reaction temperature typically reaches 65°C. The application of thiosemicarbazide after PAM staining is extremely useful in microscopy. At high temperatures, the methenamine silver reaction clearly shows the mesangium, glomerular basement membrane (GBM), and renal tubular brush border (RTBB) because of their different color tones. Optimal staining resulted in black staining of the GBM, but brown staining of the RTBB. In conclusion, optimal visualization with reproducible results is obtained by using thiosemicarbazide at high temperatures after PAM staining compared with conventional silver staining.

A blood gas analyzer that can show the respiratory and circulatory conditions as well as the general conditions of a patient can be useful for medical workers in the field. The blood gas analyzer that we used was operating normally; however, the pH of an arterial blood sample was low, and we investigated the reasons and countermeasures for this. The arterial blood sample showed a low pH of 7.282; however, the pH was 7.410 when using another type of device. The reason was that a blood clot adhered to the pH electrode, and it did not react normally with the electrode. Therefore, a blood clot detector was attached to the pH electrode so that measurements can indicate an abnormality and no measurements can be made when there is a clot. By calculating the ratio of blood clot detection using the same apparatus, we found that outpatient devices showed a significantly high ratio (p = 0.01). It is mainly used for pediatric patients, in whom blood collection and treatment are more difficult to perform. Therefore, it was considered that the rate of blood clots was higher. By attaching a blood clot detector, we can detect abnormalities in the blood gas analyzer and respond quickly. Through blood gas analysis, we can report our event as an example to introduce a technique to prevent clotting during blood sampling and a useful function for detecting clots in the apparatus.

Deproteinization is a method for removing protein components from a sample solution and is used when proteins are an obstacle for evaluating certain substances. Although several deproteinization methods have been reported, their performances have rarely been compared. In this study, we investigated the performance of each deproteinization method and evaluated whether the experimental methods were beneficial for protein detection. Deproteinization was conducted by incorporating equal amounts of one of the following solvents to the serum: ammonium saturated sulfate (AS), acetone, acetonitrile, 10% trichloroacetic acid (TCA), 1N perchloric acid, 10% sulfosalicylic acid, 10% sodium tungstate, and 2/3N sulfuric acid (TGA). Subsequently, five evaluations were conducted: confirmation of serum appearance and turbidity, Lowry method, electrophoresis, high-performance liquid chromatography (HPLC) analysis, and automated clinical chemistry. Serum treated with AS and TGA demonstrated approximately 1/2–1/3 of the protein remaining in the deproteinized samples compared to the original samples. Serum treated with TCA demonstrated excellent protein deproteinization performance, with almost no remaining proteins. The effects of deproteinization on the uric acid, urea nitrogen, and creatinine levels in the samples were minimal. Electrophoresis and HPLC evaluations were found to be superior for evaluating protein concentration in each sample compared to other evaluation methods. It is essential to select a deproteinization method that considers the effect of the treatment on the target substances in the samples.

Cardiac troponin I is a well-known selective marker of myocardial injury, and its concentration relative to the 99th percentile values of healthy subjects can predict the presence of myocardial damage. Because the high-sensitivity troponin assay is recommended by Acute Coronary Syndrome Guidelines (2018), we evaluated the performance of VITROS High-sensitivity Troponin I in this study and compared it with other high-sensitivity reagents. We obtained good results in terms of repeatability, with coefficient of variation (CV) values between 0.86% and 2.44% as well as CV values of 2.19%–4.57% for precision between days. Interference by unconjugated bilirubin occurred in a concentration-dependent decreasing trend, whereas the influence of other substances was insignificant. The correlation coefficient and 99th percentile agreement between the AIA PACK CL Troponin I were r = 0.983 and y = 0.738x − 3.39 and 92.1%, respectively, showing a good correlation. With Elecsys reagent High-sensitivity Troponin T, the respective values were r = 0.789 and y = 3.149x − 60.969 and 86.7%. Because there was a tendency of divergence around the 99th percentile value when comparing each reagent, clinical judgment based on troponin results should be considered in addition to other examination results, such as electrocardiogram. Nonetheless, VITROS High-sensitivity Troponin I was found to be the most disease specific and highly specific for acute myocardial infarction, a disease that requires immediate diagnosis.

α-solanine (SO) and α-chaconine (CHA) are natural toxins of potato and often cause food poisoning. We have previously developed a polyclonal antibody (anti-Sold antibody) that bind to SO and CHA and used them in an enzyme-linked immunosorbent assay (ELISA). This ELISA has a weak point of low sensitivity in detecting SO and CHA, we have tried to improve it in this study. The SO and CHA in the samples were coated on an ELISA plate, and biotin-labeled anti-Sold antibody and peroxidase-labeled streptavidin were added to the plate. The absorbance of the samples containing SO and CHA prepared in 10 mM phosphate buffer was about 5-fold higher than that of the conventional ELISA. Furthermore, the absorbance of the samples containing SO and CHA prepared in human serum and urine was enhanced about 2.5- and 1.6-fold, respectively, compared to that of the conventional ELISA. Using this ELISA, it was also possible to measure the content of SO and CHA in extracts of potato tubers, peels, and sprouts. On the other hand, this ELISA cross-reacted with solanidine and solasodine, which have similar chemical structures to SO and CHA, and also with cholesterol in serum. Although this ELISA has a detection performance applicable to human biological samples, cross-reactivity should be fully considered when judging the results.

The (1→3)-β-D-glucan assay used as a diagnostic aid for deep-seated mycosis has been measured by the turbidimetric time analysis method. Recently, Limsave MT-7500, which can measure the β-D-glucan using a chromogenic substrate method, has been released. Here, we report the basic performance of “β-glucan single M30 test Wako” using the chromogenic synthetic substrate method measured by Limsave MT-7500 for use in clinical examination. The chromogenic synthetic substrate method showed better results in terms of repeatability, intermediate precision, linearity, limit of determination, and influence of co-existing substances. The measurement time and non-specific reactions of this method were reduced compared to those of the turbidimetric time analysis method. The correlation between the turbidimetric time analysis method and the chromogenic synthetic substrate method in the full measuring range was determined by the passing Bablok method (y = 0.917x − 0.054 and r = 0.9562). Additionally, their positive agreement rate was 84%, negative agreement rate was 100%, the concordance rate was 87%, and there were 7 cases of discordance. Based on the case histories, we considered the possibility of BDG contamination, false-positive results of the turbidimetric time analysis method due to nonspecific reactions, and false-negative results of the chromogenic synthetic substrate method. These analysis results indicated that β-glucan single M30 test Wako using the chromogenic substrate method presented useful basic performance, which should contribute to more accurate and rapid diagnosis of deep-seated mycosis than the turbidimetric time method in clinical.

The CN-6500 fully automated blood coagulation analyzer (CN-6500; Sysmex Corporation) is an instrument that combines a measurement for coagulation-fibrinolysis molecular markers. In this study, we evaluated the basic performance of the CN-6500 in measuring thrombin-antithrombin III complex (TAT), plasmin-α2 plasmin inhibitor complex (PIC), and tissue plasminogen activator-plasminogen activator inhibitor complex (tPAI-C), which are molecular markers of the coagulation-fibrinolysis. The evaluation included repeatability, reproducibility, linearity, limit of detection, influence of interfering substances, biotin addition test, and correlation evaluation between CN-6500 and HISCL-5000 (Sysmex Corporation). The results of repeatability, reproducibility, linearity and limit of detection were favorable. No influence of hemolytic hemoglobin, bilirubin C and F, or interfering substances was observed. However, the three subject items were affected by biotin as a relative value of −10% or more. The correlation between the instruments (HISCL-5000: x, CN-6500: y) was good for TAT (y = 1.013x − 0.269, r = 0.998), PIC (y = 1.026x − 0.134, r = 0.998) and tPAI-C (y = 0.944x + 0.028, r = 0.999). Although the biotin effect was partially observed, the CN-6500 is considered to be a useful analyser for in-hospital testing of molecular markers of the coagulation-fibrinolysis.

Low-density lipoprotein cholesterol (LDL-C) estimates can be calculated on the basis of the levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG). Using the Friedewald formula, we calculated LDL-C as follows: LDL-C = (TC) − (HDL-C) − (TG/5). In most patients, the difference between TC level and HDL-C, LDL-C, and TG levels multiplied by 0.15 converges to a value of around 0 mg/dL. However, some cases show differences deviating significantly from this value. In the present study, we randomly selected patients who had their lipid profile (TC, HDL-C, LDL-C, and TG) examined between December 2019 and November 2021 and whose TC level difference ranged beyond (n = 58) and within (n = 8) 0 ± 25 mg/dL. Lipid patterns were examined by the electrophoretic analysis of lipoproteins based on the Chol/TG and LipoPhor system to measure the levels of phospholipids and free cholesterol. Of the 48 patients whose TC level difference was above ±25 mg/dL, the results indicated the presence of lipoprotein-X (LP-X) in 16 patients and either LP-X or LP-Y in 19 patients. Slow-alpha was identified in the serum of one patient, and the presence of abnormal lipoproteins could not be confirmed in 12 patients. The TG level was over 300 mg/dL in all 10 patients whose TC level difference was below 25 mg/dL. A TC level difference above ±15 mg/dL also contributed to the measurement failures and the detection of abnormal HDL-C in other patients. Our findings indicate that monitoring of the TC level difference not only contributes to the detection of abnormal lipoproteins but also in guaranteeing the quality of data on the four lipid profiles.

Venous thromboembolism, including deep vein thrombosis (DVT), often develops after surgery and childbirth, and thus, perioperative management is important. However, there are few reports related to the perioperative period of percutaneous catheter ablation (CA). We investigated and analyzed the incidence of and factors for DVT after CA by ultrasonography and determined the usefulness of lower extremity venous ultrasonography (LEUS) after CA. Of 195 consecutive patients who underwent CA for non-atrial fibrillation and LEUS on the day after surgery, 104 patients who did not receive oral anticoagulants were included in this study. We investigated the presence and location of DVT by LEUS and statistically analyzed the patient background characteristics, preoperative blood test values, and CA procedure. Eight of the 104 patients (7.7%) had DVT. The sites of DVT were the right femoral vein (FV) in two patients, the left and right soleus veins (SVs) in one patient, the left SV in four patients, and the right SV in one patient. Distal DVT was found in six patients, and proximal DVT in two patients. All proximal DVTs were on the right FV, which occurred at the same site as the puncture site. Compared with the non-DVT group, the DVT group had more patients aged 70 years or over and more patients with a history of DVT, higher D-dimer levels, and longer postoperative bed rest (p < 0.05). The occurrence of DVT in the perioperative period of CA is related to age, history of DVT, D-dimer level, and postoperative bed rest duration. LEUS is useful for the early diagnosis of DVT after CA.

We evaluated the performance of two analyzers, namely, TRCReady-80^® (TOSOH Co., TRC) and GeneXpert^® (Beckman Coulter Inc., GX), and an outsourcing test to detect the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) gene using TaqPath^® reagent (Thermo Fisher Scientific K.K., TaqPath). EDX SARS-CoV-2 Standard^® (Bio-Rad Co.) was used to determine the detection limits. It was diluted with saline and the concentrations of the SARS-CoV-2 gene were determined to be 4.3, 17, 34, 43, 170, 340, and 1,700 copies/mL. Each sample was analyzed using TRC and GX within the day. The detection limits of TRC and GX were 430 and 170 copies/mL, respectively. Nasopharyngeal swab samples were collected from 15 non-infected subjects and 13 infected subjects. Two samples were collected from each subject. The first sample was placed in universal viral transport media for analysis using GX and TaqPath. The second one was stirred well in the dedicated denaturing reagents for TRC. All the samples were measured using TRC or GX within the day and the TaqPath test was performed on the next day. All the results collected from the non-infected subjects were negative. As for the infected subjects’ samples, the SARS-CoV-2 gene was detected using GX but there were three false negatives and ten positives in the analysis using TRC or TaqPath. The samples with the discrepancy between GX and TRC or TaqPath results had high Ct values (> 35). The discrepancies seemed to be caused by the detection limit performance and the fragmentations of the SARS-CoV-2 gene in the samples. We should choose the analyzers on the basis of the difference in their characteristics.

Direct acting antivirals (DAA) therapy offers a cure for most chronic hepatitis C cases, underscoring the importance of identifying undiagnosed patients. To enhance viral hepatitis elimination, our institution introduced an HCV antibody-positive alert system in February 2018. However, initially, the system lacked the ability to effectively identify patients with hepatitis C. Since September 2022, our hepatology specialist and clinical laboratory technician team has implemented the Hepatitis Patrol system to identify patients with hepatitis C. Together with an automatic alert system, this integrated approach has significantly improved the appropriate management rate for patients with positive hepatitis C virus antibodies ordered by non-hepatology specialists, increasing it from 67% to an impressive 99%. Moreover, the system has successfully detected six previously undiagnosed hepatitis C patients, highlighting the valuable contribution of the automatic alert and Hepatitis Patrol systems in capturing cases and facilitating DAA therapy initiation. Overall, this refined system shows great promise in enhancing hepatitis C detection and treatment, delivering substantial benefits to clinical practice.

In July 2007, our hospital’s laboratory department achieved ISO 15189 accreditation. While maintaining and managing the ISO 15189 accreditation, it became a problem that the number of indications related to equipment management in internal audits did not decrease. Therefore, we developed an equipment management system to manage equipment easily and appropriately. We constructed our own relational database (RDB) using Microsoft Access installed in our hospital’s medical terminal and developed an application using Visual Basic for Applications (VBA) attached to it. When constructing the RDB, we were aware that the requirements of ISO 15189 could be managed just enough, and in order to make it possible to easily check the change history, we adopted a generation management mechanism for some tables. The constructed equipment management system was put into operation in June 2019, and so far it has worked with repeated version upgrades. Regarding the number of nonconformities related to equipment management in internal audits, the number of nonconformities decreased from 13 in 2013 before the implementation of the equipment management system to 7 in 2022 after the implementation. It is believed that the implementation of the equipment management system has made it possible to manage devices appropriately. It is also believed that the system is easy to maintain as it has been developed independently, so it is easy to fix bugs and add features, and it is easy to maintain a system that is appropriate for the current laboratory.

In recent years, Large Language Models (LLM) have gained worldwide attention in various fields. LLM are language models built using extensive datasets and deep learning techniques. LLM have garnered global attention due to their ability to exhibit human-like fluency in speech and achieve high accuracy in various natural language-based processes. In this study, we examined whether LLM could correctly solve the National Clinical Laboratory Technician Examination for the past three years. We used ChatGPT (GPT-3.5 and GPT-4), one of the LLM developed by OpenAI. The results showed that GPT-3.5 had an average correct response rate of 51.4% over the past three years, which did not reach the passing level of 60%. On the other hand, GPT-4 had an average correct response rate of 79.8%. These findings indicate that ChatGPT has potential to evolve as an effective advisor in the field of clinical laboratory science. However, the 20% of incorrect answers in this study included answers that could lead to misdiagnosis when diagnosing patients, suggesting that further improvement of the accuracy of the ChatGPT is essential. We believe that this validation will contribute to the development of various applications of ChatGPT in LLM in the clinical laboratory field, and we look forward to its further development.

It is known that β₂MG becomes a falsely low value due to acidic protease when urine pH is below 5.5. Therefore, the submission conditions for outsourced testing also state that “submit at pH 5.5 to 7.5,” but no method for pH adjustment is provided. Therefore, we aimed to clarify the relationship between urine β₂MG and pH and evaluate the appropriate submission method. The subjects were 26 outpatient specimens. Conditions for pH adjustment and differences in preservation methods (room temperature, refrigeration, freezing) were set, and compared the rate of decrease in urine β₂MG levels due to differences in the elapsed time until measurement. For samples with pH between 6.0 and 7.5, the rate of decrease in β₂MG after 24 hours was small. For samples with a pH of 4.7 to 5.5, the rate of decrease in β₂MG after 24 hours was greater in the order of room temperature storage, refrigerated storage, and frozen storage. These results indicate that urine β₂MG with a pH of 6.0 or higher is not easily affected by acid proteases, while urine β₂MG with a pH of 5.5 or lower is susceptible. In addition, in acidic urine, β₂MG decomposition was fastest when stored at room temperature, and it was thought that storage under freezing and then refrigerated storage would be less susceptible to the effects of acid proteases. Therefore, it was suggested that measurements should be taken promptly or urine pH should be confirmed immediately, and specimens should be processed and submitted for testing approp.

In recent years, the quality assurance of clinical testing has attracted attention in Japan, and the acquisition of third-party accreditation has rapidly been emphasized. Accordingly, the number of facilities that have acquired ISO 15189 certification is increasing. On the other hand, in the United States, due to the implementation of CLIA’88 (Clinical Laboratory Improvement Amendments Act 1988), all clinical laboratories that handle human specimens must be certificated by a clinical laboratory accreditation organization approved by the some government agencies. The largest and most traditional of these is the Laboratory Accreditation Program (LAP) provided by the College of American Pathologists (CAP). The National Cancer Center Hospital East has maintained ISO 15189 accreditation since 2013. Furthermore, in order to achieve our vision of “creating new world-class cancer care”, we have been aiming to obtain CAP accreditation since 2019. After about three years of preparation, we acquired CAP accreditation in August 2022. Based on our experience, we will report on the outline of CAP, the usefulness of the proficiency test, the efforts in the pathology laboratory for the inspection, the responses during the inspection, the corrective actions after the inspection, and issues identified in continuously maintaining CAP.

Introduction: Severe hyperkalemia contains risk of cardiac arrest of requiring early treatment. Our hospital sets serum potassium level exceeding 6.0 mmol/L as extreme values, and it is announced immediately to the attending physician. In this study, we investigated the response of physicians to reports and the adequacy of the current reporting system. Methods: The subjects were 131 outpatients of one-year period with hyperkalemia extreme values. We investigated the response of physicians, hyperkalemia triggers and previous treatment, emergency treatment, electrocardiographic findings, potassium level, and potassium changes. Results: Chronic kidney disease, excessive potassium intake, and the medicament side effects accounted for 80% of trigger. 20 patients required emergency procedures. Most of the patients who were treated emergently showed exceed 7.0 mmol/L or elevated above 1.5 mmol/L. When we announced hyperkalemia to the physician, eight patients had already left the hospital. Six of eight patients responded by telephone, and one of six patient required emergency treatment. Six of 29 who required electrocardiography indicated 2.0 mmol/L higher level of potassium changes. Moreover, by the analyses of biochemical items, it was revealed that the urea nitrogen changes and the creatinine changes were useful to evaluate emergent treatment requirement. Conclusions: The hyperkalemia extreme values reporting in the outpatient were evaluated to be useful by the response of physicians. For the prediction of the patients who required emergency treatment, it was necessary to fix hyperkalemia extreme values report procedure.

[Introduction] For ISO 15189-accredited laboratories, “high-quality” internal audits are very important. The competence of the personnel conducting the internal audits is an important factor; however, declining competence has become a problem. This report describes an analysis of the current status of internal audits and an evaluation of competence after the implementation of countermeasures. [Methods] From FY2019 onward internal audit committee members have played a leading role in auditing. To understand the current level of competence, we performed a statistical analysis that compared evaluations of lead auditors whose competence had been certified in FY2018 to committee members certified from FY2019 onward. We conducted the same evaluation in the first half and the second half of the two audits for the committee members. [Results] We found that the average score of the lead auditors was 41.4 and CV% was about 26%. In the evaluation of the first half of the internal audit, the committee members had improved average score (49.1) and CV% (about 13%). Moreover, one member (11.1%) had a high score. In the second half, the average score was 55.7, and five committee members (about 56.6%) had a high score. The results showed a significant difference. [Conclusion] By analyzing the results of competence and taking countermeasures, we were able to improve the competence of committee members. We will continue to carry out internal audits and improve quality consistently through continuous practice by updating evaluation criteria.

We conducted a longitudinal study on the serological IgG type SARS-CoV-2 antibody levels in healthy individuals following COVID-19 vaccination. The study included a total of seven participants, comprising men and women aged 28 to 58 years, who received their first dose of the Moderna COVID-19 vaccine (mRNA-1273) in July 2021. The second vaccination was administered one month later and the third eight months later. Post-vaccination antibody levels were measured weekly until the peak was reached, and then at four-week intervals up to 24 weeks post-vaccination. Furthermore, additional assessments were conducted for one participant who received a fourth dose and two participants who became infected with the Omicron variant. The peaks in antibody levels after the second and third doses were observed at one to two weeks and two to three weeks post-vaccination, respectively. While the antibody levels in each individual declined at a steady rate with a certain half-life, the rate of decline was slower after the third dose. In the case of individuals who were infected or received a fourth dose, the half-life further increased. This suggests that changes in immune dynamics occur due to frequent immunization, regardless of vaccination or viral infection. Additionally, graphing the antibody levels using logarithmic transformation allowed for prediction of the antibody level trends. Although multiple measurements are required, they are important for confirming vaccine efficacy and determining the timing of additional vaccinations, especially when abnormalities in antibody acquisition are suspected due to factors such as age, underlying conditions, and individual constitution.

In medical facilities, it is challenging to handle all types of specimen tests in-house due to their extensive range. Outsourced clinical testing through external service providers allows medical institutions to contract with these companies for various clinical tests. While this approach offers a broad range of test capabilities, drawbacks exist in the time required for reporting results and methods for tracking progress. In 2020, SRL Inc. developed the Solution K system aimed at automating test result retrieval, digitizing urgent fax reports, and enhancing visibility of test completion dates. However, each medical institution has its own policy for managing medical information systems. Challenges also arise in the establishment of network infrastructure, coupled with the increasing complexity of network management and security measures. To improve our clinical department’s support services, our hospital engaged in repeated discussions with the medical information department to secure network management and security. As of September 2023, we have commenced the rapid and transparent reporting of outsourced clinical test results via the in-house implementation of the Solution K system. This paper aims to detail the process of integrating the Solution K system within our facility.

At our hospital, all 15 blood collection tables are in operation from 8:00 am, and an average of about 700 people per day are being collected. Conventionally, the waiting time for blood collection was always more than 60 minutes in the morning, and alleviating congestion was an issue for hospitals. As an improvement, we introduced a “blood collection system that matches the appointment time for examinations and examinations” and made effort to adapt to the environment of the blood collection room. After the introduction of this system, the average waiting time was 10 minutes, shortening by about 30 minutes.

Ensuring the quality of clinical laboratory testing requires effective management and maintenance of processes from blood collection to laboratory analysis. This study aimed to validate the utility of hemolysis monitoring by focusing on factors contributing to hemolysis in the pre-examination process and providing concrete examples. Based on measured serum data, hemolysis was categorized into four levels, namely, 0, 1+, 2+, and > 2+, and corresponding counts and hemolysis rates were calculated. Cases with high hemolysis rates because of centrifuge damage enabled the early detection of centrifuge malfunctions through a comparison of hemolysis rates between two centrifuges and daily monitoring. In another case where a change in the manufacturer of butterfly needles led to reduced hemolysis rates, the potential to observe the effect of alterations on pre-examination processes, such as modifications in blood collection tools and techniques, was emphasized. Another case had high hemolysis rates caused by an elevated silicone coating on needles during butterfly needle manufacturing, highlighting the effectiveness of monitoring as an objective indicator for early anomaly detection. Additional cases revealed low hemolysis rates through adjustments in the blood collection volume concerning vacuum blood collection tube capacity. Collecting more than half of the tube’s capacity resulted in a significant reduction in hemolysis rates, a reduction that was further decreased using smaller vacuum collection tubes. These examples underscore the value of monitoring hemolysis rates in the test samples for the early detection of anomalies in pre-examination processes.

The reform of work styles of physicians and other healthcare workers is in full swing. As a result of conducting a survey of the clinical departments and nursing department at our hospital regarding their expectations of the laboratory for task shifting/sharing, early morning blood draw in the wards was cited as high demand. Therefore, we carried out an early morning blood draw with the highest number of blood samplings as trial wards for six months. To verify the effectiveness of the trial wards, we conducted a questionnaire survey before, during, and after the implementation of this project for the nursing department. To evaluate the usefulness of this project, we compared the number of re-drawn blood samplings in the target wards before and after blood sampling by our department began. The results showed that to assist in blood collection in the wards was highly effective, for example, the enhancement of patient care by nurses in the early morning hours. In particular, a significant improvement was observed in the number of re-drawn blood. Furthermore, staff in charge for the project could move up their work hours by two hours, which was also found to be effective in their respective work-life balances. In conclusion, support for blood collection in hospital wards by clinical laboratory not only reduces the blood sampling duties of nurses, but also useful for patients, and has the potential to raise the level of medical care at this hospital and to provide better and safer medical care.