Prediction of the minimum amount of anti-adhesive agent required for entire intra-abdominal cavity using fluorescent dye.

PURPOSE: Studies on the appropriate amount of anti-adhesive agents for preventing postoperative adhesion are lacking. This animal study aimed to investigate the distribution of an anti-adhesive agent in the abdominal cavity and estimate the necessary amount to cover the entire cavity. METHODS: Fluorescent dye Flamma-552 was conjugated to Guardix-sol to create Guardix-Flamma, which was laparoscopically applied to the abdominal cavity of two 10-kg pigs in different amounts: 15 mL for G1 and 35 mL for G2. After 24 hours, the distribution of Guardix-Flamma was examined under the near-infrared mode of the laparoscope, and the thickness was measured in tissues from the omentum, small, and large intestine by immunohistochemistry. RESULTS: The average area of the abdominal cavity in 10 kg pigs was 2,755 cm2. Guardix-Flamma fluorescence was detected in the greater omentum, ascites in the pelvis, and right quadrant area in G1, whereas in G2, it was detected everywhere. On average, the total thickness of G1 and G2 were 12.68 ± 9.80 µm and 18.16 ± 15.57 µm, respectively. Guardix-Flamma thickness applied to the omentum, small, and large intestines of G2 were 1.31-, 1.45-, and 1.49-times thicker than those of G1, respectively, and were all statistically significant (P < 0.05). CONCLUSION: The entire abdominal cavity of the 10 kg pig was not evenly covered with 15 mL of Guardix. Although 35 mL of Guardix is sufficient to cover the same area with an average thickness of 18 µm, further studies should evaluate the minimum thickness required for an effective anti-adhesive function.

Trends in clinical outcomes of older hemodialysis patients: data from the 2023 Korean Renal Data System (KORDS).

With an increasing aging population, the mean age of patients with end-stage kidney disease (ESKD) is globally increasing. However, the current clinical status of elderly patients undergoing hemodialysis (HD) is rarely reported in Korea. The current study analyzed the clinical features and trends of older patients undergoing HD from the Korean Renal Data System (KORDS) database. The patients were divided into three groups according to age: <65 years (the young group), n = 50,591 (35.9%); 65-74 years (the younger-old group), n = 37,525 (26.6%); and ≥75 years (the older-old group), n = 52,856 (37.5%). The proportion of older-old group undergoing HD significantly increased in incidence and decreased in prevalence from 2013 to 2022. The median levels of hemoglobin, serum creatinine, albumin, calcium, phosphorus, and intact parathyroid hormone significantly decreased in the older-old group. The proportions of arteriovenous fistula creation and left forearm placement showed decreased trends with age. Although the utilization of low surface area dialyzers increased with age, the dialysis adequacy, including urea reduction ratio and Kt/V was within acceptable range in the older-old group on HD. Over the past 20 years, the mortality rate in the older-old group has increased, with cardiovascular diseases decreasing and infectious diseases increasing. The incidence of elderly patients undergoing HD has increased over time, but the high mortality of the older-old group needs to be solved. Therefore, it is imperative to develop holistic strategies based on age and individual needs for patients with ESKD.

Symmetry-breaking motility of penetrable objects in active fluids.

We investigate how a symmetric penetrable object immersed in an active fluid becomes motile due to a negative drag acting in the direction of its velocity. While similar phenomena have been reported only for active fluids that possess polar or nematic order, we demonstrate that such motility can occur even in active fluids without any preexisting order. The emergence of object motility is characterized by both continuous and discontinuous transitions associated with the symmetry-breaking bifurcation of the object's steady-state velocity. Furthermore, we also discuss the relevance of the transitions to the nonmonotonic particle-size dependence of the object's diffusion coefficient.

Status and trends in epidemiologic characteristics of diabetic end-stage renal disease: an analysis of the 2021 Korean Renal Data System.

Korean Renal Data System (KORDS) is a nationwide end-stage renal disease (ESRD) registry database operated by the Korean Society of Nephrology (KSN). Diabetes mellitus is currently the leading cause of ESRD in Korea; this article provides an update on the trends and characteristics of diabetic ESRD patients. The KORDS Committee of KSN collects data on dialysis centers and patients through an online registry program. Here, we analyzed the status and trends in characteristics of diabetic chronic kidney disease stage 5D (CKD 5D) patients using data from 2001 to 2021. In 2021, the dialysis adequacy of hemodialysis (HD) was lower in diabetic CKD 5D patients than in nondiabetic CKD 5D patients, while that of peritoneal dialysis (PD) was similar. Diabetic CKD 5D patients had a higher proportion of cardiac and vascular diseases and were more frequently admitted to hospitals than nondiabetic CKD 5D patients, and the leading cause of death was cardiac disease. From 2001 to 2020, diabetic CKD 5D patients had a higher mortality rate than nondiabetic CKD 5D patients, but in 2021 this trend was reversed. Diabetic PD patients had the highest mortality rate over 20 years. The mortality rate of diabetic HD patients was higher than that of nondiabetic HD patients until 2019 but became lower starting in 2020. There was a decreasing trend in mortality rate in diabetic CKD 5D patients, but cardiac and vascular diseases were still prevalent in diabetic CKD 5D patients with frequent admissions to hospitals. More specialized care is needed to improve the clinical outcomes of diabetic CKD 5D patients.

Association between anxiety and skin conductance according to the intensity of shaking of virtual reality images.

Introduction: Despite the advantages of virtual reality (VR), cyber sickness makes it difficult to apply VR to those who are already anxious and in distress. Skin conductance (SC) is widely used as a bio-signal reflecting anxiety. It is positively correlated with anxiety. The objective of this study was to determine the association between SC and anxiety in VR. Methods: Healthy volunteers with moderate-to-high stress defined as a Perceived Stress Scale-10 (PSS-10) score ≥20 were enrolled. STAI-X-1 was used to measure anxiety, and galvanic skin response was used to measure SC. This study used an open, randomized, crossover design. In this study, 360° videos consisted of two types, namely, less dizzying video (G1) and more dizzying video (G2). We randomized subjects into two groups according to video exposure order: G1 after watching G2 (Order 1) and G2 after watching G1 (Order 2). Of 81 subjects, the average age (±SD) was 39.98 ± 10.94 years for the Order 1 group and 36.54 ± 12.44 years for the Order 2 group. Results: Anxiety was significantly decreased in the Order 2 group (p < 0.035) after watching videos, whereas there was no significant change in anxiety in the Order 1 group. In both groups, SC was significantly increased after exposure to a dizzying video. Mean difference (SD) between the second VR video and baseline SC was 1.61 (1.07) (p < 0.0001) in the Order 1 group and 0.92 (0.90) (p < 0.0001) in the Order 2 group, showing a significant difference between the two groups (p < 0.003). However, there was no significant difference between the two groups (p < 0.077) after baseline correction. Conclusion: Anxiety was decreased significantly in the Order 2 group. The Order 1 group showed a high rate of change in skin conductivity. It is possible to reduce SC and anxiety by viewing a less dizzying VR video first and then viewing a more dizzying video later.

Primary Bilateral Tuberculous Otitis Media After Kidney Transplantation: A Case Report.

We report a case of primary bilateral tuberculous otitis media in a patient who underwent kidney transplantation. This case presents unusual clinical features and histopathology from those of classical tuberculous otitis media. A 75-year-old woman presented at the clinic with purulent ear discharge and hearing loss in both ears. She had undergone kidney transplantation 6 years prior and had been taking immunosuppressant medications. Otoscopic examination and imaging studies suggested acute otitis media, which was irresponsive to antibiotics. The patient underwent surgery to eradicate the disease, and histopathologic examination revealed multifocal granulomas with Langhans giant cells without caseous changes. Ziehl-Neelsen staining and polymerase chain reaction confirmed the diagnosis of tuberculous otitis media. While tuberculous otitis media is a very rare manifestation of extrapulmonary tuberculosis, this case is more noteworthy in that it occurred as a primary infection rather than as a reactivation of a prior infection. In addition, it did not show the classical triad of clinical manifestations, which occurred bilaterally, and its histopathology was different from those of classical tuberculous otitis media. This case presents a new clinical variation in tuberculous otitis media.

Objective Tinnitus of Nasopharyngeal Origin.

We report a rare case of objective tinnitus induced by nasopharyngeal muscle constriction. A 49-year-old female patient presented at the clinic with unintentional sounds coming from the nasal cavity while talking or swallowing, which were similar to the lip-smacking sound. Physical examination revealed a hypertrophic posterior nasopharyngeal wall and torus tubarius at rest. With voluntary effort, the posterior pharyngeal wall protruded prominently and collided with the torus tubarius on either side, generating a sound when they were separated. Botox injection was recommended but the patient refused. The diagnosis and treatment of objective tinnitus are well established, but in some cases, it may occur under unexpected conditions. We report a novel type of objective tinnitus. A thorough physical examination for tinnitus could reveal the cause.

Monoradiculopathy-induced abdominal pseudohernia caused by T11-12 soft disc herniation: a case report and literature review.

BACKGROUND: An abdominal pseudohernia is a rare clinical entity that consists of an abnormal bulging of the abdominal wall that can resemble a true hernia but does not have an associated underlying fascial or muscle defect. Abdominal pseudohernia is believed to result from denervation of the abdominal muscles in cases of herpes zoster infection, diabetes mellitus, lower thoracic or upper lumbar disc herniation, surgical injuries, and rib fracture. To date, nine cases of abdominal pseudohernia caused by disc herniation at the lower thoracic or upper lumbar levels have been reported. CASE PRESENTATION: A 35-year-old man with no underlying disease or traumatic event presented with chief complaints of left flank pain and a protruding left lower abdominal mass that had formed one day earlier. There was no true abdominal hernia on abdominal computed tomography (CT), although CT and magnetic resonance imaging (MRI) showed a herniated soft (non-calcified) disc into the left neural foramen at the T11-12 level. A nonsteroidal anti-inflammatory drug was prescribed for the flank pain, and the patient was followed on a regular basis for six months. Follow-up MRI taken at the last visit showed complete resorption of the herniated disc. Abdominal pseudohernia and flank pain were also completely resolved. CONCLUSION: We report a rare case of monoradiculopathy-induced abdominal pseudohernia caused by foraminal soft disc herniation at the T11-12 level. In patients who have an abdominal pseudohernia without herpes zoster infection, diabetes mellitus, or traumatic events, lower thoracic disc herniations should be included in differential diagnosis.

The Polysulfide-Cathode Binding Energy Landscape for Lithium Sulfide Growth in Lithium-Sulfur Batteries.

A cathode substrate with strong adsorption of lithium polysulfides (LiPSs) has been preferred for lithium-sulfur (Li-S) batteries. However, the recent finding that controlled growth of lithium sulfides (Li2 S) during discharge is crucial for S utilization stimulates improvement of this preference. Here, the Li2 S growth and cell capacity in the LiPS binding energy landscape of cathode substrates are investigated. Specifically, Co-based ternary oxides are employed to obtain binding energies in the range of 4.0-7.4 eV. Of these substrates, only the MnCo2 O4 substrate with moderate LiPS affinity exhibits 3D Li2 S growth. The MnCo2 O4 cells achieve high sulfur utilization up to 84% at 0.2 C and excellent performance even under high sulfur loading/lean electrolyte conditions. In contrast, weak affinity substrates such as ZnCo2 O4 and strong affinity substrates such as NiCo2 O4 and CuCo2 O4 exhibit low discharge capacity with 2D Li2 S growth. For optimal LiPS affinity driving 3D growth, a balance between promoting LiPS adsorption and diffusion limitation in the LiPS adsorption layer is suggested.

Effect of Lumbar Spinal Stenosis on Treatment of Osteoporosis: Comparison of Three Oral Bisphosphonate Therapies.

(1) Background: Lumbar spinal stenosis (LSS) causes uncomfortable neuropathic symptoms, which can negatively affect osteoporosis. The aim of this study was to investigate the effect of LSS on bone mineral density (BMD) in patients treated with one of three oral bisphosphonates (ibandronate, alendronate and risedronate) for initially diagnosed osteoporosis. (2) Methods: We included 346 patients treated with oral bisphosphonates for three years. We compared annual BMD T-scores and BMD increases between the two groups according to symptomatic LSS. The therapeutic efficacies of the three oral bisphosphonates in each group were also evaluated. (3) Results: Annual and total increases in BMD were significantly greater in group I (osteoporosis) compared to group II (osteoporosis + LSS). The total increase in BMD for three years was significantly greater in the ibandronate and alendronate subgroups than that in the risedronate subgroup (0.49 vs. 0.45 vs. 0.25, p < 0.001). Ibandronate showed a significantly greater increase in BMD than that of risedronate in group II (0.36 vs. 0.13, p = 0.018). (4) Conclusions: Symptomatic LSS may interfere with the increase in BMD. Ibandronate and alendronate were more effective in treating osteoporosis than risedronate. In particular, ibandronate was more effective than risedronate in patients with both osteoporosis and LSS.

Segmental artery injury during transforaminal percutaneous endoscopic lumbar discectomy: Two case reports.

BACKGROUND: Since Kambin experimentally induced arthroscopy to treat herniated nucleus pulposus, percutaneous endoscopic lumbar discectomy (PELD) has been developed. The branch of the segmental artery around the neural foramen may be damaged during PELD using the transforaminal approach. We report 2 rare cases in which segmental artery injury that occurred during PELD was treated with emergency embolization. CASE SUMMARY: In case 1, a 31-year-old man was transferred to our emergency department with left lower quadrant abdominal pain after PELD at a local hospital. Lumbar spine magnetic resonance imaging after the surgery showed a hematoma of the left retroperitoneal area and the psoas muscle area. Under suspicion of vascular injury, arteriography was performed. Pseudoaneurysm and blood leakage from the left 4th lumbar segmental artery into the abdominal cavity were identified. Emergency transarterial embolization was performed using fibered microcoils for bleeding of the segmental artery. In case 2, a 75-year-old woman was transferred to our emergency department with low blood pressure, right flank pain, and drowsy mental status after PELD at a local hospital. When the patient arrived at the emergency room, the blood pressure decreased from 107/55 mmHg to 72/47 mmHg. Low blood pressure persisted. Under suspicion of vessel injury, arteriography was performed, and the right 4th lumbar segmental artery rupture was confirmed. Emergency transarterial embolization was performed for bleeding of segmental artery. CONCLUSION: We were able to find the bleeding focus by angiography and treat the injury of the segmental artery successfully through emergency transarterial embolization.

Lumbar Interbody Fusion and Osteobiologics for Lumbar Fusion.

Lumbar interbody fusion (LIF) is an excellent treatment option for a number of lumbar diseases. LIF can be performed through posterior, transforaminal, anterior, and lateral or oblique approaches. Each technique has its own pearls and pitfalls. Through LIF, segmental stabilization, neural decompression, and deformity correction can be achieved. Minimally invasive surgery has recently gained popularity and each LIF procedure can be performed using minimally invasive techniques to reduce surgery-related complications and improve early postoperative recovery. Despite advances in surgical technology, surgery-related complications after LIF, such as pseudoarthrosis, have not yet been overcome. Although autogenous iliac crest bone graft is the gold standard for spinal fusion, other bone substitutes are available to enhance fusion rate and reduce complications associated with bone harvest. This article reviews the surgical procedures and characteristics of each LIF and the osteobiologics utilized in LIF based on the available evidence.

A Study on the Factors Affecting Anger in Patients With Post-traumatic Stress Disorder.

OBJECTIVE: To identify the factors affecting anger in post-traumatic stress disorder (PTSD) patients who underwent Clinician-Administered PTSD Scale (CAPS) and Minnesota Multiphasic Personality Inventory-2 (MMPI-2). METHODS: We retrospectively reviewed patients who underwent CAPS and MMPI-2 at Veteran Health Service Medical Center, Seoul, Korea. Based on the CAPS score, the patients were divided into the PTSD group (n=46) and the trauma exposed without PTSD group (n=29). After checking the correlation between anger, CAPS, and MMPI-2 scales, logistic regression analysis was performed to identify the risk factors for clinically relevant symptoms. RESULTS: The PTSD group showed significant differences in schizophrenia-related symptoms, ideas of persecution, aggressiveness, psychoticism, and anger scales compared to the trauma-exposed without PTSD group. There was a significant correlation between anger, CAPS, and MMPI-2 except masculinity/femininity, disconstraint, and MacAndrew Alcoholism-Revised. In particular, anger has been shown to have a substantial connection with paranoia, schizophrenia-related symptoms, ideas of persecution, aberrant experiences, and psychoticism. Multiple regression analysis identified that the only significant risk factor for anger was the negative emotionality/neuroticism scale (odds ratio=1.152, p<0.001). CONCLUSION: The PTSD group had increased anger compared to the trauma-exposed without PTSD group, and that negative emotions may be a risk factor for PTSD.

A Machine-Learning-Algorithm-Based Prediction Model for Psychotic Symptoms in Patients with Depressive Disorder.

Psychotic symptoms are rarely concurrent with the clinical manifestations of depression. Additionally, whether psychotic major depression is a subtype of major depression or a clinical syndrome distinct from non-psychotic major depression remains controversial. Using data from the Research on Asian Psychotropic Prescription Patterns for Antidepressants, we developed a machine-learning-algorithm-based prediction model for concurrent psychotic symptoms in patients with depressive disorders. The advantages of machine learning algorithms include the easy identification of trends and patterns, handling of multi-dimensional and multi-faceted data, and wide application. Among 1171 patients with depressive disorders, those with psychotic symptoms were characterized by significantly higher rates of depressed mood, loss of interest and enjoyment, reduced energy and diminished activity, reduced self-esteem and self-confidence, ideas of guilt and unworthiness, psychomotor agitation or retardation, disturbed sleep, diminished appetite, and greater proportions of moderate and severe degrees of depression compared to patients without psychotic symptoms. The area under the curve was 0.823. The overall accuracy was 0.931 (95% confidence interval: 0.897-0.956). Severe depression (degree of depression) was the most important variable in the prediction model, followed by diminished appetite, subthreshold (degree of depression), ideas or acts of self-harm or suicide, outpatient status, age, psychomotor retardation or agitation, and others. In conclusion, the machine-learning-based model predicted concurrent psychotic symptoms in patients with major depression in connection with the "severity psychosis" hypothesis.

Delayed Recovery in Idiopathic Sudden Sensorineural Hearing Loss.

Sudden hearing loss is an easily encountered disease in clinics, but its prognosis has not been completely elucidated. In the present study, we investigated the long-term prognosis of sudden hearing loss with 130 patients who were diagnosed based on strict criteria and provided uniform treatment. The patients with incomplete recovery were reevaluated after 2 months without receiving additional treatment. Hearing levels at different time points were compared. Moreover, the associated factors affecting the degree of hearing improvement over time were evaluated using stepwise multiple linear regression. After treatment, 73 out of the 130 (56.1%) patients attained incomplete recovery and were reevaluated after 2 months. Seventeen out of the seventy-three (23.3%) patients showed a grade promotion, fifty-four (74%) were constant, and two (2.7%) were aggravated. The mean interaural hearing differences (IHDs) showed significant improvement. Old age, poor initial IHD, and poor recovery grade were significantly associated with a profitable delayed hearing gain. Poorer hearing level at the time of onset might be a sign for slower recovery rather than a poorer prognostic factor. The treatment outcome of idiopathic sudden sensorineural hearing loss (ISSNHL) should be evaluated at least 2 months after treatment completion, and counseling is required due to the need for long-term follow-up in patients with ISSNHL.

Novel Polymorphisms and Genetic Characteristics of the Shadow of Prion Protein Gene (SPRN) in Cats, Hosts of Feline Spongiform Encephalopathy.

Prion diseases are transmissible spongiform encephalopathies (TSEs) caused by pathogenic prion protein (PrPSc) originating from normal prion protein (PrPC) and have been reported in several types of livestock and pets. Recent studies have reported that the shadow of prion protein (Sho) encoded by the shadow of prion protein gene (SPRN) interacts with prion protein (PrP) and accelerates prion diseases. In addition, genetic polymorphisms in the SPRN gene are related to susceptibility to prion diseases. However, genetic polymorphisms in the feline SPRN gene and structural characteristics of the Sho have not been investigated in cats, a major host of feline spongiform encephalopathy (FSE). We performed amplicon sequencing to identify feline SPRN polymorphisms in the 623 bp encompassing the open reading frame (ORF) and a small part of the 3' untranslated region (UTR) of the SPRN gene. We analyzed the impact of feline SPRN polymorphisms on the secondary structure of SPRN mRNA using RNAsnp. In addition, to find feline-specific amino acids, we carried out multiple sequence alignments using ClustalW. Furthermore, we analyzed the N-terminal signal peptide and glycosylphosphatidylinositol (GPI)-anchor using SignalP and PredGPI, respectively. We identified three novel SNPs in the feline SPRN gene and did not find strong linkage disequilibrium (LD) among the three SNPs. We found four major haplotypes of the SPRN polymorphisms. Strong LD was not observed between PRNP and SPRN polymorphisms. In addition, we found alterations in the secondary structure and minimum free energy of the mRNA according to the haplotypes in the SPRN polymorphisms. Furthermore, we found four feline-specific amino acids in the feline Sho using multiple sequence alignments among several species. Lastly, the N-terminal signal sequence and cutting site of the Sho protein of cats showed similarity with those of other species. However, the feline Sho protein exhibited the shortest signal sequence and a unique amino acid in the omega-site of the GPI anchor. To the best of our knowledge, this is the first report on genetic polymorphisms of the feline SPRN gene.

Balancing Electrolyte Donicity and Cathode Adsorption Capacity for High-Performance LiS Batteries.

LiS batteries with high theoretical capacity are attracting attention as next-generation energy storage systems. Much effort has been devoted to the introduction of cathode materials with strong adsorption to sulfide species, but it is presented that this selection should be refined in the application of high donicity electrolytes. The oxides with different adsorption capacities are explored while controlling the electrolyte donicity, confirming the trade-off effect between the donicity and the adsorption capacity for sulfur conversion. Specifically, a cathode substrate containing oxide nanoparticles of MgO, NiO, Fe2 O3 , Co3 O4 , and V2 O5 is prepared with spectra in adsorption capacity as well as low and high donicity electrolytes by controlling the concentration of LiNO3 salt. Strong adsorbent oxides such as Co3 O4 and V2 O5 cause competitive adsorption of electrolyte salts in high donicity electrolytes, resulting in poor cell performance. High cell performance is achieved on weakly adsorbing oxides of MgO or NiO with high donicity electrolytes; the MgO-containing cathode cell delivers a high discharge capacity of 1394 mAh g-1 at 0.2 C. It is believed that understanding the interactions between electrolytes and adsorbent substrates will be the cornerstone of high-performance LiS batteries.

Shared genetic architectures of subjective well-being in East Asian and European ancestry populations.

Subjective well-being (SWB) has been explored in European ancestral populations; however, whether the SWB genetic architecture is shared across populations remains unclear. We conducted a cross-population genome-wide association study for SWB using samples from Korean (n = 110,919) and European (n = 563,176) ancestries. Five ancestry-specific loci and twelve cross-ancestry significant genomic loci were identified. One novel locus (rs12298541 near HMGA2) associated with SWB was also identified through the European meta-analysis. Significant cross-ancestry genetic correlation for SWB between samples was observed. Polygenic risk analysis in an independent Korean cohort (n = 22,455) demonstrated transferability between populations. Significant correlations between SWB and major depressive disorder, and significant enrichment of central nervous system-related polymorphisms heritability in both ancestry populations were found. Hence, large-scale cross-ancestry genome-wide association studies can advance our understanding of SWB genetic architecture and mental health.

Clinical Approaches to Late-Onset Psychosis.

Psychosis can include schizophrenia, mood disorders with psychotic features, delusional disorder, active delirium, and neurodegenerative disorders accompanied by various psychotic symptoms. Late-onset psychosis requires careful intervention due to the greater associated risks of secondary psychosis; higher morbidity and mortality rates than early-onset psychosis; and complicated treatment considerations due to the higher incidence of adverse effects, even with the black box warning against antipsychotics. Pharmacological treatment, including antipsychotics, should be carefully initiated with the lowest dosage for short-term efficacy and monitoring of adverse side effects. Further research involving larger samples, more trials with different countries working in consortia, and unified operational definitions for diagnosis will help elaborate the clinical characteristics of late-onset psychosis and lead to the development of treatment approaches.

Korean Society of Nephrology hemodialysis unit accreditation report (2016-2020) and future directions.

BACKGROUND: Patients receiving hemodialysis have various complications with a high mortality rate and require specialized treatment at an institution equipped with an appropriate workforce, equipment, and facilities. The Korean Society of Nephrology (KSN) is conducting hemodialysis unit accreditation to manage the quality of hemodialysis institutions, present standard treatment guidelines, and establish a network between regional medical institutions for the safe treatment of hemodialysis patients. This study aimed to summarize the previous accreditation results and discuss future directions. METHODS: After the proposal of hemodialysis unit accreditation in 2009, pilot projects were undertaken for hemodialysis units and dialysis subspecialist training hospitals in the metropolitan area for 5 years. Since 2016, five hemodialysis unit accreditation projects have been conducted. RESULTS: The cumulative number of participating units was 599, and the number of accredited units was 473 (average accreditation rate, 79.0%). The participating units consisted of clinics (58.6%), non-university hospitals (28.2%), and university hospitals (13.2%). Overall, 92.4% of university hospitals, 81.2% of clinics, and 68.0% of non-university hospitals were accredited. Over 5 years, new units were added annually to apply for accreditation, and the rate of previous participants applying for reaccreditation was high (77.7%). However, considering that the total number of member institutions of the KSN is 637, the number of units with valid accreditation as of 2020 was low (267 [41.9%]). CONCLUSION: The efforts of the KSN and its members, as well as institutional support from the government, are required for quality management of hemodialysis units through hemodialysis unit accreditation.