1.Kidney biopsy can help to predict renal outcomes of patients with type 2 diabetes mellitus
Wook-Joon KIM ; Taehoon OH ; Nam Hun HEO ; Kyungsup KWON ; Ga-Eun SHIN ; Se-Hwi JEONG ; Ji Hye LEE ; Samel PARK ; Nam-Jun CHO ; Hyo-Wook GIL ; Eun Young LEE
Kidney Research and Clinical Practice 2025;44(1):91-101
In patients with type 2 diabetes mellitus (T2DM), diabetic kidney disease (DKD) is diagnosed based on clinical features. A kidney biopsy is used only in selected cases. This study aimed to reconsider the role of a biopsy in predicting renal outcomes. Methods: Clinical and laboratory parameters and renal biopsy results were obtained from 237 patients with T2DM who underwent renal biopsies at Soonchunhyang University Cheonan Hospital between January 2000 and March 2020 and were analyzed. Results: Of 237 diabetic patients, 29.1% had DKD only, 61.6% had non-DKD (NDKD), and 9.3% had DKD with coexisting NDKD (DKD/NDKD). Of the patients with DKD alone, 43.5% progressed to end-stage kidney disease (ESKD), while 15.8% of NDKD patients and 36.4% of DKD/NDKD patients progressed to ESKD (p < 0.001). In the DKD-alone group, pathologic features like ≥50% global sclerosis (p < 0.001), tubular atrophy (p < 0.001), interstitial fibrosis (p < 0.001), interstitial inflammation (p < 0.001), and the presence of hyalinosis (p = 0.03) were related to worse renal outcomes. The Cox regression model showed a higher risk of progression to ESKD in the DKD/NDKD group compared to the DKD-alone group (hazard ratio [HR], 2.73; p = 0.032), ≥50% global sclerosis (HR, 3.88; p < 0.001), and the degree of mesangial expansion (moderate: HR, 2.45; p = 0.045 and severe: HR, 6.22; p < 0.001). Conclusion: In patients with T2DM, a kidney biopsy can help in identifying patients with NDKD for appropriate treatment, and it has predictive value.
2.Loss of Cutibacterium is responsible for chronic kidney disease-associated pruritus in patients on dialysis
Jeong Geon LEE ; Hoonhee SEO ; Seung Seob SON ; Hee Seul JEONG ; Kyung Mi LEE ; Nam-Jun CHO ; Samel PARK ; Hyo-Wook GIL ; Hyun-A PARK ; Sukyung KIM ; Eun Young LEE
Kidney Research and Clinical Practice 2025;44(1):176-188
Chronic kidney disease (CKD)-associated pruritus is a severe distressing condition that frequently occurs in patients undergoing dialysis. In this study, the profile of the skin microbiome was analyzed to understand the underlying etiology and potential treatments. Methods: Seventy-six end-stage kidney disease (ESKD) patients (hemodialysis, 40; peritoneal dialysis, 36) and 15 healthy controls were enrolled and swabbed at three sites: back, antecubital fossa, and shin. The pruritus severity of the enrolled subjects was validated by the Worst Itch Numeric Rating Scale (WI-NRS), 5-D itch scale, and Uremic Pruritus in Dialysis Patients (UP-Dial). The 16S genebased metagenomics method was applied to skin microbiome analysis. Results: In the comparison of bacterial communities of ESKD patients and the control group, there was a significant difference on back. Specifically, the average composition ratio of the Cutibacterium in the back samples was significantly lower in ESKD patients than in healthy controls (p < 0.01). In further analysis of ESKD patients, Cutibacterium was significantly lower in the high pruritus group than in the low pruritus group (p < 0.05), even though other clinical parameters such as age, calcium-phosphorus product, and intact parathyroid hormone showed no significance difference between the groups. Conclusion: In ESKD patients, the skin microbiome of the back was significantly altered, and the severity of itching was related to the reduction of Cutibacterium. This research reveals the relationship between skin microbiota and CKD-associated pruritus in multiple skin sites for the first time. The results of this study suggest a potential data basis for the diagnosis and treatment of CKD-associated pruritus.
3.A machine learning-based approach for predicting renal function recovery in general ward patients with acute kidney injury
Nam-Jun CHO ; Inyong JEONG ; Yeongmin KIM ; Dong Ok KIM ; Se-Jin AHN ; Sang-Hee KANG ; Hyo-Wook GIL ; Hwamin LEE
Kidney Research and Clinical Practice 2024;43(4):538-547
Acute kidney injury (AKI) is a significant challenge in healthcare. While there are considerable researches dedicated to AKI patients, a crucial factor in their renal function recovery, is often overlooked. Thus, our study aims to address this issue through the development of a machine learning model to predict restoration of kidney function in patients with AKI. Methods: Our study encompassed data from 350,345 cases, derived from three hospitals. AKI was classified in accordance with the Kidney Disease: Improving Global Outcomes. Criteria for recovery were established as either a 33% decrease in serum creatinine levels at AKI onset, which was initially employed for the diagnosis of AKI. We employed various machine learning models, selecting 43 pertinent features for analysis. Results: Our analysis contained 7,041 and 2,929 patients’ data from internal cohort and external cohort respectively. The Categorical Boosting Model demonstrated significant predictive accuracy, as evidenced by an internal area under the receiver operating characteristic (AUROC) of 0.7860, and an external AUROC score of 0.7316, thereby confirming its robustness in predictive performance. SHapley Additive exPlanations (SHAP) values were employed to explain key factors impacting recovery of renal function in AKI patients. Conclusion: This study presented a machine learning approach for predicting renal function recovery in patients with AKI. The model performance was assessed across distinct hospital settings, which revealed its efficacy. Although the model exhibited favorable outcomes, the necessity for further enhancements and the incorporation of more diverse datasets is imperative for its application in real- world.
4.Genome-wide association study and fine-mapping on Korean biobank to discover renal trait-associated variants
Dong-Jin LEE ; Jong-Seok MOON ; Dae Kwon SONG ; Yong Seok LEE ; Dong-Sub KIM ; Nam-Jun CHO ; Hyo-Wook GIL ; Eun Young LEE ; Samel PARK
Kidney Research and Clinical Practice 2024;43(3):299-312
Chronic kidney disease is a significant health burden worldwide, with increasing incidence. Although several genome- wide association studies (GWAS) have investigated single nucleotide polymorphisms (SNP) associated with kidney trait, most studies were focused on European ancestry. Methods: We utilized clinical and genetic information collected from the Korean Genome and Epidemiology Study (KoGES). Results: More than five million SNPs from 58,406 participants were analyzed. After meta-GWAS, 1,360 loci associated with estimated glomerular filtration rate (eGFR) at a genome-wide significant level (p = 5 × 10–8) were identified. Among them, 399 loci were validated with at least one other biomarker (blood urea nitrogen [BUN] or eGFRcysC) and 149 loci were validated using both markers. Among them, 18 SNPs (nine known ones and nine novel ones) with 20 putative genes were found. The aggregated effect of genes estimated by MAGMA gene analysis showed that these significant genes were enriched in kidney-associated pathways, with the kidney and liver being the most enriched tissues. Conclusion: In this study, we conducted GWAS for more than 50,000 Korean individuals and identified several variants associated with kidney traits, including eGFR, BUN, and eGFRcysC. We also investigated functions of relevant genes using computational methods to define putative causal variants.
5.Indoxyl sulfate induces apoptotic cell death by inhibiting glycolysis in human astrocytes
Seung-Hyun JEONG ; Samel PARK ; Jae-sung CHOI ; Nam-Jun CHO ; Jong-Seok MOON ; Hyo-Wook GIL
Kidney Research and Clinical Practice 2024;43(6):774-784
Neurologic complications, such as cognitive and emotional dysfunction, have frequently been observed in chronic kidney disease (CKD) patients. Previous research shows that uremic toxins play a role in the pathogenesis of CKD-associated cognitive impairment. Since astrocytes contribute to the protection and survival of neurons, astrocyte function and brain metabolism may contribute to the pathogenesis of neurodegeneration. Indoxyl sulfate (IS) is the most popular uremic toxin. However, how IS-induced astrocyte injury brings about neurologic complications in CKD patients has not been elucidated. Methods: The rate of extracellular acidification was measured in astrocytes when IS (0.5–3 mM, 4 or 7 days) treatment was applied. The hexokinase 1 (HK1), pyruvate kinase isozyme M2 (PKM2), pyruvate dehydrogenase (PDH), and phosphofructokinase (PFKP) protein levels were also measured. The activation of the apoptotic pathway was investigated using a confocal microscope, fluorescence- activated cell sorting, and cell three-dimensional imaging was used. Results: In astrocytes, IS affected glycolysis in not only dose-dependently but also time-dependently. Additionally, HK1, PKM2, PDH, and PFKP levels were decreased in IS-treated group when compared to the control. The results were prominent in cases with higher doses and longer exposure duration. The apoptotic features after IS treatment were also observed. Conclusion: Our results showed that the inhibition of glycolysis by IS in astrocytes leads to cell death via apoptosis. Specifically, longterm and higher-dose exposures had more serious effects on astrocytes. Our results suggest that the glycolysis pathway and related targets could provide a novel approach to cognitive dysfunction in CKD patients.
6.Indoxyl sulfate induces apoptotic cell death by inhibiting glycolysis in human astrocytes
Seung-Hyun JEONG ; Samel PARK ; Jae-sung CHOI ; Nam-Jun CHO ; Jong-Seok MOON ; Hyo-Wook GIL
Kidney Research and Clinical Practice 2024;43(6):774-784
Neurologic complications, such as cognitive and emotional dysfunction, have frequently been observed in chronic kidney disease (CKD) patients. Previous research shows that uremic toxins play a role in the pathogenesis of CKD-associated cognitive impairment. Since astrocytes contribute to the protection and survival of neurons, astrocyte function and brain metabolism may contribute to the pathogenesis of neurodegeneration. Indoxyl sulfate (IS) is the most popular uremic toxin. However, how IS-induced astrocyte injury brings about neurologic complications in CKD patients has not been elucidated. Methods: The rate of extracellular acidification was measured in astrocytes when IS (0.5–3 mM, 4 or 7 days) treatment was applied. The hexokinase 1 (HK1), pyruvate kinase isozyme M2 (PKM2), pyruvate dehydrogenase (PDH), and phosphofructokinase (PFKP) protein levels were also measured. The activation of the apoptotic pathway was investigated using a confocal microscope, fluorescence- activated cell sorting, and cell three-dimensional imaging was used. Results: In astrocytes, IS affected glycolysis in not only dose-dependently but also time-dependently. Additionally, HK1, PKM2, PDH, and PFKP levels were decreased in IS-treated group when compared to the control. The results were prominent in cases with higher doses and longer exposure duration. The apoptotic features after IS treatment were also observed. Conclusion: Our results showed that the inhibition of glycolysis by IS in astrocytes leads to cell death via apoptosis. Specifically, longterm and higher-dose exposures had more serious effects on astrocytes. Our results suggest that the glycolysis pathway and related targets could provide a novel approach to cognitive dysfunction in CKD patients.
7.Indoxyl sulfate induces apoptotic cell death by inhibiting glycolysis in human astrocytes
Seung-Hyun JEONG ; Samel PARK ; Jae-sung CHOI ; Nam-Jun CHO ; Jong-Seok MOON ; Hyo-Wook GIL
Kidney Research and Clinical Practice 2024;43(6):774-784
Neurologic complications, such as cognitive and emotional dysfunction, have frequently been observed in chronic kidney disease (CKD) patients. Previous research shows that uremic toxins play a role in the pathogenesis of CKD-associated cognitive impairment. Since astrocytes contribute to the protection and survival of neurons, astrocyte function and brain metabolism may contribute to the pathogenesis of neurodegeneration. Indoxyl sulfate (IS) is the most popular uremic toxin. However, how IS-induced astrocyte injury brings about neurologic complications in CKD patients has not been elucidated. Methods: The rate of extracellular acidification was measured in astrocytes when IS (0.5–3 mM, 4 or 7 days) treatment was applied. The hexokinase 1 (HK1), pyruvate kinase isozyme M2 (PKM2), pyruvate dehydrogenase (PDH), and phosphofructokinase (PFKP) protein levels were also measured. The activation of the apoptotic pathway was investigated using a confocal microscope, fluorescence- activated cell sorting, and cell three-dimensional imaging was used. Results: In astrocytes, IS affected glycolysis in not only dose-dependently but also time-dependently. Additionally, HK1, PKM2, PDH, and PFKP levels were decreased in IS-treated group when compared to the control. The results were prominent in cases with higher doses and longer exposure duration. The apoptotic features after IS treatment were also observed. Conclusion: Our results showed that the inhibition of glycolysis by IS in astrocytes leads to cell death via apoptosis. Specifically, longterm and higher-dose exposures had more serious effects on astrocytes. Our results suggest that the glycolysis pathway and related targets could provide a novel approach to cognitive dysfunction in CKD patients.
8.Indoxyl sulfate induces apoptotic cell death by inhibiting glycolysis in human astrocytes
Seung-Hyun JEONG ; Samel PARK ; Jae-sung CHOI ; Nam-Jun CHO ; Jong-Seok MOON ; Hyo-Wook GIL
Kidney Research and Clinical Practice 2024;43(6):774-784
Neurologic complications, such as cognitive and emotional dysfunction, have frequently been observed in chronic kidney disease (CKD) patients. Previous research shows that uremic toxins play a role in the pathogenesis of CKD-associated cognitive impairment. Since astrocytes contribute to the protection and survival of neurons, astrocyte function and brain metabolism may contribute to the pathogenesis of neurodegeneration. Indoxyl sulfate (IS) is the most popular uremic toxin. However, how IS-induced astrocyte injury brings about neurologic complications in CKD patients has not been elucidated. Methods: The rate of extracellular acidification was measured in astrocytes when IS (0.5–3 mM, 4 or 7 days) treatment was applied. The hexokinase 1 (HK1), pyruvate kinase isozyme M2 (PKM2), pyruvate dehydrogenase (PDH), and phosphofructokinase (PFKP) protein levels were also measured. The activation of the apoptotic pathway was investigated using a confocal microscope, fluorescence- activated cell sorting, and cell three-dimensional imaging was used. Results: In astrocytes, IS affected glycolysis in not only dose-dependently but also time-dependently. Additionally, HK1, PKM2, PDH, and PFKP levels were decreased in IS-treated group when compared to the control. The results were prominent in cases with higher doses and longer exposure duration. The apoptotic features after IS treatment were also observed. Conclusion: Our results showed that the inhibition of glycolysis by IS in astrocytes leads to cell death via apoptosis. Specifically, longterm and higher-dose exposures had more serious effects on astrocytes. Our results suggest that the glycolysis pathway and related targets could provide a novel approach to cognitive dysfunction in CKD patients.
9.Machine learning approaches toward an understanding of acute kidney injury: current trends and future directions
Inyong JEONG ; Nam-Jun CHO ; Se-Jin AHN ; Hwamin LEE ; Hyo-Wook GIL
The Korean Journal of Internal Medicine 2024;39(6):882-897
Acute kidney injury (AKI) is a significant health challenge associated with adverse patient outcomes and substantial economic burdens. Many authors have sought to prevent and predict AKI. Here, we comprehensively review recent advances in the use of artificial intelligence (AI) to predict AKI, and the associated challenges. Although AI may detect AKI early and predict prognosis, integration of AI-based systems into clinical practice remains challenging. It is difficult to identify AKI patients using retrospective data; information preprocessing and the limitations of existing models pose problems. It is essential to embrace standardized labeling criteria and to form international multi-institutional collaborations that foster high-quality data collection. Additionally, existing constraints on the deployment of evolving AI technologies in real-world healthcare settings and enhancement of the reliabilities of AI outputs are crucial. Such efforts will improve the clinical applicability, performance, and reliability of AKI Clinical Support Systems, ultimately enhancing patient prognoses.
10.Clinical Practice Guidelines for Oropharyngeal Dysphagia
Seoyon YANG ; Jin-Woo PARK ; Kyunghoon MIN ; Yoon Se LEE ; Young-Jin SONG ; Seong Hee CHOI ; Doo Young KIM ; Seung Hak LEE ; Hee Seung YANG ; Wonjae CHA ; Ji Won KIM ; Byung-Mo OH ; Han Gil SEO ; Min-Wook KIM ; Hee-Soon WOO ; Sung-Jong PARK ; Sungju JEE ; Ju Sun OH ; Ki Deok PARK ; Young Ju JIN ; Sungjun HAN ; DooHan YOO ; Bo Hae KIM ; Hyun Haeng LEE ; Yeo Hyung KIM ; Min-Gu KANG ; Eun-Jae CHUNG ; Bo Ryun KIM ; Tae-Woo KIM ; Eun Jae KO ; Young Min PARK ; Hanaro PARK ; Min-Su KIM ; Jungirl SEOK ; Sun IM ; Sung-Hwa KO ; Seong Hoon LIM ; Kee Wook JUNG ; Tae Hee LEE ; Bo Young HONG ; Woojeong KIM ; Weon-Sun SHIN ; Young Chan LEE ; Sung Joon PARK ; Jeonghyun LIM ; Youngkook KIM ; Jung Hwan LEE ; Kang-Min AHN ; Jun-Young PAENG ; JeongYun PARK ; Young Ae SONG ; Kyung Cheon SEO ; Chang Hwan RYU ; Jae-Keun CHO ; Jee-Ho LEE ; Kyoung Hyo CHOI
Journal of the Korean Dysphagia Society 2023;13(2):77-106
Objective:
Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one’s physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia.
Methods:
Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology.
Results:
Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended.
Conclusion
This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

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