Objective To explore the clinical characteristics and risk factors of sarcopenia in elderly patients with chronic kidney disease (CKD) stage 3-4. Methods It was a single-center, retrospective observational study. CKD stage 3-4 patients aged ≥60 years old from March 2019 to March 2022 in the Geriatrics Department of the First Affiliated Hospital of Zhengzhou University were enrolled in the study. General data of the patients were collected, and laboratory indicators, muscle strength, physical function and appendicular muscle mass index (ASMI) were measured. According to the diagnostic criteria of sarcopenia, the patients were divided into no sarcopenia CKD group and sarcopenia CKD group. Baseline data between these two groups were compared. Logistic regression analysis was used to analyze the related factors of sarcopenia in elderly CKD stage 3-4 patients. Results A total of 162 CKD stage 3-4 patients were enrolled in this study, with 89 males (54.9%) and a median age of 75 (69, 82) years. Sarcopenia was diagnosed in 40 cases, and the prevalence was 24.7% (95% CI 18.1%-31.3%). Compared with no sarcopenia CKD group, age, proportion of dementia, cystatin C, urea nitrogen, C-reactive protein (CRP) and ratio of urine protein to creatinine were higher (all P<0.05), while body mass index (BMI), hemoglobin, carbon dioxide combining power, estimated glomerular filtration rate (eGFR), serum albumin and the proportion of regular exercise and using α-ketones were lower in sarcopenia CKD group (all P<0.05). Meanwhile, grip strength, walking speed, short physical performance battery score and ASMI were lower in sarcopenia CKD group (all P<0.05). Multivariable logistic regression analysis results showed that low eGFR (OR=0.824, 95% CI 0.687-0.987, P=0.036), low BMI (OR=0.463, 95% CI 0.304-0.704, P<0.001), low serum albumin (OR=0.459, 95% CI 0.263-0.802, P=0.006) and high CRP (OR=2.754, 95% CI 1.708-4.439, P<0.001) were the independent related factors of sarcopenia in elderly CKD patients. Conclusions The prevalence of sarcopenia in elderly CKD stage 3-4 patients is high. Low eGFR, low BMI, low serum albumin and high CRP are the independent risk factors for sarcopenia in elderly CKD stage 3-4 patients.

Objective To screen the incidence of proteinuria in rural areas of Shanxi province and construct a risk prediction model of proteinuria based on machine learning algorithm. Methods It was a cross-sectional investigation study. The residents ≥30 years old in rural areas of Shanxi province from April to November 2019 were screened by multi-stage stratified sampling method, and data from questionnaire surveys, physical examinations, and laboratory examinations were collected. Urine albumin/creatinine ratio ≥30 mg/g was defined as proteinuria, and the incidence of proteinuria was calculated. Subjects were divided into proteinuria group and non-proteinuria group. The machine learning binary classification model of proteinuria and non-proteinuria was constructed based on the stackable integrated logistic regression algorithm (SE-LR), logistic regression, support vector machine, decision tree, random forest and extreme gradient lift algorithms, respectively. The area under the receiver operating characteristic curve, accuracy, recall, and F1 weights were used to evaluate the predictive efficiency of the comparison models. Finally, the importance of the predictive features of the model with the best overall performance was ranked. Results There were 8 869 rural residents included in the study, aged (58.59±9.49) years old, with 3 872 males (43.66%) and 4 997 females (56.34%). The prevalence of proteinuria in rural areas of Shanxi province was 13.49% (1 196/8 869). Blood pressure, pulse, body mass index, waist circumference, proportion of obesity or overweight, proportion of hypertension, proportion of moderate to severe salt intake, glycosylated hemoglobin, uric pH value, urinary specific gravity, proportion of positive urinary occult blood, proportion of positive urinary glucose, proportion of positive urinary ketone body, proportion of urinary red blood cell count ≥5/μl, proportion of urinary white blood cell count ≥10/μl and urinary α1 microglobulin in the proteinuria group were all higher than those in the non-proteinuria group (all P<0.05). The proportions of lack of exercise and drinking history in the proteinuria group were lower than those in non-proteinuria group (both P<0.05). The overall performance of SE-LR model was the best, with the area under the curve (0.736, 95% CI 0.719-0.746) slightly lower than that of the logistic regression model (0.745, 95% CI 0.680-0.762), and the highest accuracy (0.844), recall rate (0.621) and F1 weighting value (0.801). In the SE-LR model, the orders of importance of the top 10 features were urinary α1- microglobulin, urinary occult blood, urinary sugar, uric acid basicity, smoking history,overweight or obesity, body mass index, total cholesterol, glycosylated hemoglobin and hypertension. Conclusions The prevalence of proteinuria is high in rural areas of Shanxi province. The risk prediction model of proteinuria established by machine learning algorithm can predict the risk of proteinuria and identify its risk factors, which can provide a scientific basis for disease prevention, intervention, and treatment in the community and clinic to a certain extent.

Objective To investigate the characteristics of renal disease spectrum in children aged 0-3 years old, and to evaluate the clinical value of renal biopsy in children aged 0-3 years old with renal diseases. Methods It was a retrospective analysis study. The children aged 0-3 years old with kidney diseases receiving renal biopsy and having complete clinical data in Shanghai Children's Hospital from January 1, 2009 to December 31, 2020 were enrolled. The clinical and pathological data of the children were collected. The spectrum of renal diseases, clinical phenotype, renal pathology, and the relationship between renal pathology/genotype and clinical phenotype were analyzed. Results A total of 117 children aged 0-3 years old with kidney diseases were enrolled in the study, accounting for 6.5% (117/1 790) of all children (0-18 years old) with renal biopsies during the same period. There were 77 males and 40 females. The age was (2.20±0.51) years old (5-35 months). All cases of renal biopsies in children aged 0-3 years old were successful without serious complications. Nephrotic syndrome was the common clinical phenotype of kidney diseases in children aged 0-3 years old (59.0%, 69/117), followed by hematuria and proteinuria (29.1%, 34/117). Primary glomerular disease (69.2%, 81/117) was the major clinical type of renal diseases, followed by hereditary kidney diseases (29.1%, 34/117), in which Alport syndrome was the main hereditary kidney disease (79.4%, 27/34). Renal pathological types of children aged 0-3 years old were mainly distributed in minimal change disease (30.8%, 36/117), followed by glomerular minor lesion (26.5%, 31/117), mesangial proliferative glomerulonephritis (15.4%, 18/117), and focal segmental glomerulosclerosis (10.3%, 12/117). Among 40 children aged 0-3 years old with hematuria with/without proteinuria, 25 cases were diagnosed as Alport syndrome by abnormal immunofluorescence of type IV collagen in renal tissues. Among the 28 children with kidney diseases who underwent genetic testing, 23 cases had gene mutations, mainly in COL4A5 gene (60.9%, 14/23), among which 4 children had gene mutations in 8 children with refractory nephrotic syndrome. Among the children aged 0-3 years old with clinical manifestations of hematuria, the proportion of gross hematuria in children diagnosed with Alport syndrome (59.3%, 16/27) was significantly higher than that in children without Alport syndrome (20.0%, 3/15, χ²=5.999, P=0.014). Conclusions Primary glomerular disease is the principal type of kidney diseases in children aged 0-3 years old, followed by hereditary kidney disease. Attention should be paid to children aged 0-3 years old with gross hematuria. Renal biopsy in children aged 0-3 years old is safe and reliable, and it is an essential means for the diagnosis of renal diseases. Renal biopsy combined with gene testing can better understand the etiology of kidney diseases and guide treatment in children aged 0-3 years old.

Objective To explore the clinical value of N terminal pro B type natriuretic peptide (NT-proBNP) in diagnosing or predicting heart failure in peridialysis chronic kidney disease (CKD) population. Methods It was a single-center retrospective study. Patients with peridialysis CKD who visited the Department of Nephrology, First Affiliated Hospital of Zhengzhou University from January 2021 to June 2021 were collected and divided into 4 groups according to the presence or absence of heart failure and the level of left ventricular ejection fraction (LVEF), namely the non-heart failure group, heart failure with reduced ejection fraction (HFrEF) group (LVEF<40%), heart failure with mid-range ejection fraction (HFmrEF) group (40％≤LVEF<50％), and heart failure with preserved ejection fraction (HFpEF) group (LVEF≥50％). The NT-proBNP, echocardiography and other indicators of the 4 groups were compared. The value of plasma NT-proBNP in diagnosing heart failure, HFpEF, HFmrEF and HFrEF was analyzed by drawing receiver operating characteristic curve (ROC curve). Logistic regression analysis was used to analyze the related factors of heart failure in peridialysis CKD patients. Results A total of 508 patients were included, including 11 cases in the HFrEF group, 29 cases in the HFmrEF group, 152 cases in the HFpEF group, and 316 cases without heart failure. The differences in age, 24-h urine volume, hemodialysis proportion, non-dialysis proportion, serum creatinine, estimated glomerular filtration rate, hemoglobin, serum albumin, C-reactive protein, NT-proBNP, cardiac troponin I, left ventricular internal diameter, LVEF, pulmonary artery systolic pressure, left ventricular end-diastolic volume, E/A value, septal thickness, and left ventricular posterior wall thickness among the four groups were statistically significant (P < 0.05, respectively). A two-pair comparison (all P values corrected by Bonferroni method) revealed that the 24-h urine volume was higher in the non-heart failure group than in the other three groups (corrected P<0.05, respectively), while the proportion of hemodialysis patients and the levels of NT-proBNP and C-reactive protein were lower in the non-heart failure group than in the other three groups (corrected P<0.001, respectively); the levels of hemoglobin and serum albumin were lower in the HFpEF group than in the non-heart failure group (corrected P<0.001, respectively); troponin I was lower in the non-heart failure group than in the HFpEF group (corrected P<0.001), HFmrEF group (corrected P=0.001) and HFrEF group (corrected P<0.001), and troponin I was lower in the HFpEF group than in the HFrEF group (corrected P=0.008); LVEF was higher in the non-heart failure group than in the other three groups (corrected P<0.001, respectively), and LVEF in the HFpEF group was higher than in the HFmrEF and HFrEF groups (corrected P<0.001, respectively). For patients with peridialysis CKD, the cut-off values of plasma NT-proBNP for diagnosing or predicting heart failure, HFpEF, HFmrEF and HFrEF were 4 943.33 ng/L, 4 976.83 ng/L, 14 964.5 ng/L and 17 847.55 ng/L, respectively. Multivariate logistic regression analysis showed that NT-proBNP (every 500 ng/L increase, OR=1.390, 95% CI 1.287-1.501, P<0.001), LVEF (OR=0.747, 95% CI 0.656-0.851, P<0.001) and 24-h urine volume (every 100 ml increase, OR=0.842, 95% CI 0.763-0.929, P=0.001) were independently correlated with heart failure. Conclusions The cut-off value of plasma NT-proBNP for diagnosing or predicting heart failure in peridialysis CKD patients is much higher than that in patients with normal renal function. NT-proBNP, LVEF and 24-h urine volume are independently associated with heart failure in peridialysis CKD patients.

Objective To explore the prevalence rate of restless leg syndrome (RLS) and its related influencing factors in patients with maintenance hemodialysis (MHD) in Anhui province. Methods It was a cross-sectional study, including regular MHD patients in blood purification centers of 27 hospitals in southern, central and northern Anhui province from January to March 2020. The investigation included general demographic characteristics, primary diseases, complications, dialysis-related conditions and drug use. According to the presence or absence of RLS, the patients were divided into RLS group and non-RLS group, and the differences of clinical data between the two groups were compared. Logistic regression analysis method was used to analyze the influencing factors of RLS. Results The study included 3 025 MHD patients, aged (54.8±12.8) years old, with 1 819 males (60.1%) and 1 206 females (39.9%). The dialysis age was (5.5±3.8) years. The prevalence rates of RLS in MHD patients were 8.8% (265/3 025), of which 13.7% (77/561), 7.7% (88/1 145) and 7.6% (100/1 319) in southern, central and northern Anhui province, respectively. The prevalence rates of RLS in MHD patients in secondary and tertiary hospitals were 9.5% (55/577) and 8.6% (210/2 448), respectively. Proportion of hypertension, dialysis age, intact parathyroid hormone, alkaline phosphatase, 25(OH)D3, and proportions of secondary hyperparathyroidism, erythropoietin use, iron supplements, active vitamin D use, calcimimetic use, dialysis blood flow <250 ml/min and low-flux dialyzers in RLS group were higher than those in non-RLS group, while hemoglobin level and proportions of non-calcium-phosphorus binders and high-flux dialyzers were lower than those in non-RLS group (all P<0.05). Multivariate logistic regression analysis results showed that long dialysis age (OR=1.188, 95% CI 1.031-1.369, P=0.017) and high alkaline phosphatase (OR=1.007, 95% CI 1.001-1.013, P=0.047) were correlated with a higher risk of RLS in MHD patients. Conclusions The prevalence rate of RLS in MHD patients in Anhui province is 8.8%. The prevalence rates of RLS in MHD patients in southern, central and northern Anhui province are 13.7%, 7.7% and 7.6%, respectively. The prevalence rate of RLS in secondary and tertiary hospitals are 9.5% and 8.6%, respectively. Long dialysis age and high alkaline phosphatase are associated with a high risk of RLS in MHD patients.

Objective To investigate the role and mechanism of N⁶-methyladenosine (m⁶A) methyltransferase-like 3 (METTL3) in vascular calcification (VC) of chronic kidney disease (CKD) through apoptosis-associated protein. Methods (1) Real-time fluorescence quantitative PCR was used to test METTL3 mRNA in serum of maintenance hemodialysis (MHD) patients. (2) Western blotting was used to detect the expression of METTL3 protein in high-phosphorus stimulated vascular smooth muscle cells (VSMCs), and immunofluorescence double lable was used to observe the distribution of METTL3 and Runt-related transcription factor 2 (Runx2). The METTL3 overexpressed and knockdown plasmids were constructed and transfected into VSMCs. Alizarin red staining was used to detect calcification degree. Western blotting was used to detect the expressions of osteogenic markers [Runx2, bone morphogenetic protein-2(BMP-2), collagen Ⅰ] and apoptosis- related proteins Bax and Bcl-2. (3) SD rats were randomly divided into control group, CKD-VC group and S-adenosylhomocysteine (SAH) intervention group. The calcification of thoracic aorta was evaluated by von Kossa staining, and the protein expressions of Runx2, Bax and Bcl-2 were detected by immunohistochemistry and Western blotting. Results (1) METTL3 mRNA expression in MHD patients with VC was significantly lower than that in non-VC patients (P<0.05), and was negatively correlated with coronary artery calcium score (r=-0.65, P<0.001). (2) The expression of METTL3 in VSMCs stimulated by high phosphorus was decreased and showed a time dependence. Immunofluorescence double label showed that METTL3 and Runx2 were co-expressed in the nucleus. METTL3 was overexpressed in high-phosphorus induced VSMCs, and the expressions of Runx2, collagen I and BMP-2 were significantly decreased, accompanied by the decrease of calcified nodules and Bax/Bcl-2 ratio (all P<0.05). Conversely, METTL3 knockdown aggravated VSMCs calcification by inducing apoptosis. (3) Furthermore, METTL3 inhibitor SAH was administered in vivo, and it was found that inhibition of METTL3 expression significantly increased the calcification of rat thoracic aorta, and the Bax/Bcl-2 ratio and Runx2 expression were up-regulated. Conclusions Serum METTL3 level is reduced in MHD patients with VC. In vivo and in vitro studies demonstrate that METTL3 inhibits VC in CKD by mediating the apoptosis-related protein Bax/Bcl-2.

It was a retrospective study. The patients with type 2 diabetes mellitus (T2DM) who underwent renal biopsy in the Department of Nephrology, the First Affiliated Hospital of Xi'an Jiaotong University from 2015 to 2021 were enrolled to analyze the pathological and clinical manifestations of kidney. There were 483 patients enrolled, including 136 patients who had no history of diabetes mellitus, newly diagnosed as T2DM according to an oral glucose tolerance test. The age was (52.80±13.13) years old. There were 337 males (69.77%). Based on the renal biopsy, the patients were classified as diabetic kidney disease (DKD, 22.15%, 107/483), DKD+non-diabetic kidney disease (NDKD)(6.63%, 32/483), and NDKD (71.22%, 344/483). Membranous nephropathy was the most common pathology in patients with NDKD (40.41%, 139/344) and DKD+NDKD (34.38%, 11/32). In the 136 newly diagnosed T2DM patients, there were 3 patients (2.21%) with DKD, 2 patients (1.47%) with DKD+NDKD, and 131 patients with NDKD (96.32%). The proportions of DKD in patients with diabetes history ≤3 months, 3-12 months, 1-5 years, 5-10 years and ≥10 years were 10.53% (6/57), 25.00% (16/64), 26.53% (26/98), 41.56% (32/77) and 47.06% (24/51), respectively. The proportions of DKD+NDKD in patients with diabetes history ≤3 months, 3-12 months, 1-5 years, 5-10 years and ≥10 years were 3.51% (2/57), 3.13% (2/64), 10.20% (10/98), 9.09% (7/77) and 17.65% (9/51), respectively. Multivariate logistic regression analysis results showed that, the duration of diabetes history (OR=1.130, 95% CI 1.057-1.208, P<0.001), diabetes retinopathy (OR=12.185, 95% CI 5.331-27.849, P<0.001), urinary red blood cell count (OR=0.987, 95% CI 0.974-0.999, P=0.039), glycosylated hemoglobin (OR=1.482, 95% CI 1.119-1.961, P=0.006) as well as hemoglobin (OR=0.973, 95% CI 0.957-0.990, P=0.001) were independently correlated with DKD. The proportions of DKD and DKD+NDKD increase with the prolongation of diabetes history. Membranous nephropathy is the most common pathology in NDKD and DKD+NDKD patients. Even in patients newly diagnosed with T2DM, it is necessary to screen for DKD. The duration of diabetes history, diabetes retinopathy, urinary red blood cell count, glycosylated hemoglobin and hemoglobin may be used to identify DKD from NDKD.

This paper reports a case of peritonitis caused by Campylobacter fetus in a continuous ambulatory peritoneal dialysis (CAPD) patient. The patient was a middle-aged man, with chronic kidney disease stage 5 secondary to chronic glomerulonephritis, and had been on CAPD for 6 years. He was admitted to our department with a 7 day history of abdominal pain and cloudy effluent. Peritoneal effluent culture was negative and metagenomic next-generation sequencing suggested Campylobacter fetus. Intraperitoneal treatment with amikacin was failed. Peritoneal dialysis catheter was removed and hemodialysis treatment was performed. After treatment of erythromycin oral for 4 weeks, the patient's symptoms was improved and discharged.

Bardet-Biedl syndrome (BBS) is an autosomal recessive hereditary rare disease with high heterogeneity in clinical phenotypes, which can affect multiple systems, such as six fingers/digits deformity, mental impairment, retinopathy, polycystic kidney, etc, and is easily diagnosed according to a single system disease, resulting in misdiagnosis. The paper reports a case of BBS, diagnosed with "renal cyst, developmental delay, chondrosis, and left foot hexadactylism" at 5 years old, "anemia, renal insufficiency, distal renal tubule poisoning, renal osteodystrophy" at 7 years old. At 10 years old, the patient received hemodialysis treatment for uremia. Cloudy vision appeared in both eyes at 14 years old. Because of the prominent manifestation of kidney damage, the patient was misdiagnosed as "polycystic kidney" for a long time, and other systemic damages were ignored. The result of gene sequencing showed that chromosome 16 NM_031885.5 exon17 had one homozygous nonsense mutation. Therefore, the patient was accurately diagnosed as BBS. This paper is the first report of BBS in Li nationality in China. The relevant literature of BBS were reviewed to strengthen clinicians' understanding of the disease and improve patients' prognosis.

Targeted therapy and immunotherapy have achieved great success in treating various solid and non-solid tumors, but the incidence of drugs-related adverse events is relatively high. The paper reports a case of renal thrombotic microangiopathy in an intrahepatic cholangiocarcinoma patient who underwent targeted therapy combined with immunotherapy. During the treatment, the tumor burden relieved continuously, but the patient developed proteinuria, edema and hypertension. The ADAMTS13 activity and inhibitors were normal, while the antiphospholipid antibody was positive. The patient was finally diagnosed as glomerular thrombotic microangiopathy with immune complex deposition by renal biopsy. After the cease of the antineoplastic agents and treatment with "cordyceps preparations" and "α-keto acids", the patient's blood pressure dropped to normal, her urine protein turnned to weakly positive, and her renal function remained stable.

Renal fibrosis (RF) is the key pathological feature for the progression of chronic kidney disease to end-stage renal failure. It has been an important scientific issue to understand its mechanism of RF in the field of kidney diseases in the past near two centuries. The progress of science and technology has not only provided a strong tool for RF research, but also given us many new ideas for RF prevention and treatment. The paper briefly reviews the key histories of RF research, with focuses on early studies of renal fibrosis, application of renal biopsy technology, establishment of RF animal models, advancements in cell and molecular biotechnology, and exploration into mechanisms underlying RF, to clarify future directions for chronic kidney disease prevention and treatment research.

Systemic lupus erythematosus (SLE) is an autoimmune disease that causes damage to multiple vital tissues and target organs, and lupus nephritis (LN) is a serious complication of SLE involving the kidneys. The use of glucocorticoids and immunosuppressants has been dominant in the treatment strategy of LN, while their adverse effects have also raised concerns. In recent years, the development and use of biologics have provided new ideas for the treatment of LN and have also achieved positive efficacy in several clinical trials in SLE and LN. Biologics can be divided into monoclonal antibodies and recombinant proteins, which exert therapeutic effects on SLE and LN through a variety of mechanisms at the cellular-molecular level. In this article, we review recent research advances in the treatment of SLE and LN from the perspective of the different mechanisms of action of biologics.

Diabetic kidney disease (DKD) is a primary cause of chronic kidney disease and end-stage renal disease, as well as one of the most common microvascular consequences of diabetes mellitus. Obesity, as a metabolic disease, has a substantial impact on the onset and progression of DKD. Epidemiological studies have revealed obesity is a risk factor of DKD and end-stage renal disease, which can promote the occurrence and progression of DKD through various mechanisms, including alterations in hemodynamics, metabolic regulation, and chronic inflammation. Clinical researches also have demonstrated the importance of various weight loss interventions in the prevention and management of DKD. Therefore, gaining a deeper understanding of the correlation between obesity and DKD will contribute to improving the prognosis and quality of life of individuals with diabetes mellitus. The paper reviews the relationship between obesity and DKD on the epidemiological characteristics of obesity and DKD, the potential mechanism of obesity affecting DKD and the influence of obesity intervention on DKD.