Objective To explore the characteristics and evolution trend of renal disease spectrum in Ningxia. Methods The demographic, clinical manifestations and renal pathological examination results of patients who underwent renal biopsies in the General Hospital of Ningxia Medical University from August 1, 2008 to December 31, 2019 were collected and analyzed retrospectively. According to the time period of receiving renal biopsy, the patients were divided into 2008—2013 group and 2014—2019 group. The age and sex constituent, clinical manifestation, renal disease type, pathological types of primary and secondary glomerular disease and the main clinical manifestations of patients with diabetic nephropathy were compared between the two groups. The changing trend of renal disease spectrum in Ningxia from 2008 to 2019 was analyzed. Results A total of 3 867 patients who underwent renal biopsies were enrolled in this study, with more males (53.71%, 2 077/3 867), and age of (39.59±14.05) years old. The most common clinical manifestation of patients receiving renal biopsies was nephrotic syndrome (36.33%, 1 405/3 867). Among them, primary glomerular diseases accounted for 78.79%(3047/3 867), followed by secondary glomerular diseases (18.57%, 718/3 867), renal tubulointerstitial diseases (1.45%, 56/3 867) and hereditary nephropathy (1.19%, 46/3 867). The most common primary glomerular disease was IgA nephropathy (44.60%, 1 359/3 047), followed by membranous nephropathy (30.75%, 937/3 047). The most common secondary glomerular disease was Henoch-Sch?nlein purpura nephritis (27.44%, 197/718), followed by lupus nephritis (25.07%, 180/718). Compared with the 2008—2013 group, the proportion of membranous nephropathy increased, the proportion of mesangial proliferative glomerulonephritis (non-IgA deposition) decreased (both P<0.001), the proportions of diabetic nephropathy and hypertensive renal damage increased, and the proportions of Henoch-Sch?nlein purpura nephritis and hepatitis B virus-associated glomerulonephritis decreased in 2014—2019 group (all P<0.01). Compared with the 2008—2013 group, the proportions of acute kidney injury, chronic renal failure, simple hematuria and urinary protein≤1.0 g/24 h increased in kidney biopsy patients in 2014—2019 group, while the proportion of nephrotic syndrome decreased (all P<0.05). Compared with the 2008—2013 group, the proportion of chronic renal failure in diabetic nephropathy patients increased during renal biopsy, and the proportion of albuminuria with hematuria decreased in 2014—2019 group (all P<0.05). Conclusions Primary glomerular disease is the most common kidney disease in Ningxia. IgA nephropathy is the most common cause, and the proportion of membranous nephropathy is increasing year by year. Henoch-Sch?nlein purpura nephritis is the most common secondary glomerular disease, and the proportions of diabetic nephropathy and hypertensive renal damage are increasing year by year, suggesting that the screening of renal complications of metabolic diseases in Ningxia should be strengthened and pay more attention to the patients with mild abnormal urine test.

Objective To analyze the changes in serum metabolites of patients with uremia using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS), and provide a theoretical basis for the prevention and treatment of uremia. Methods Uremia patients from the Department of Nephrology, the Affiliated Hospital of Southwest Medical University, and the volunteers from the Health Examination Center were enrolled in this study. According to the inclusion and exclusion criteria, 20 uremia patients (experimental group) and 20 volunteers (control group) were screened out. UHPLC-MS was used to detect the metabolites in the serum of subjects from the two groups, and difference analysis was made to screen the different metabolites, followed by correlation analysis and pathway enrichment study. Results A total of 412 metabolites were identified by UHPLC-MS. Principal components analysis (PCA) proved that these metabolites could distinguish the control group and the experimental group well. The criteria [variable importance for the projection (VIP)>1, fold changes (FC)>1.25 or FC<0.8 and P value<0.05] was set to screen those significantly different metabolites. Finally, 28 significantly different metabolites were screened out, of which 18 metabolites increased significantly, the other 10 different metabolites decreased significantly. Correlation analysis results proved a certain correlation among 28 different metabolites and the experimental group and control group samples, and between the 28 differential metabolites themselves. Enrichment analysis found that 28 different metabolites might enrich the catecholamine biosynthetic pathway, and pathway analysis suggested that 28 different metabolites might affect glutamate, aspartame acid and glutamate metabolic pathways. Conclusion Based on metabonomic analysis, some metabolites in the serum of patients with uremia have changed, which can affect some metabolic pathways, thus affecting the pathophysiological process of patients with uremia.

Objective To explore the clinical and histopathologic features of lupus nephritis (LN) patients with positive antineutrophil cytoplasmic antibody (ANCA), so as to provide more theoretical basis to recognize and treat this disease. Methods Clinical data of biopsy-proven LN patients with ANCA test in the First Affiliated Hospital of Sun Yat-sen University from November 1, 2002 to September 11, 2020 were collected and analyzed retrospectively. The difference of clinical data, laboratory examination, and pathological examination of renal biopsy between ANCA-positive group and ANCA-negative group. The clinicopathological characteristics between different ANCA serotypes were compared. Results A total of 1 304 patients with LN confirmed by renal biopsy and ANCA test results were enrolled. Eighty ANCA-positive patients from 1 304 LN patients were screened. There are 55(68.8%) ANCA-positive LN patients with positive anti-myeloperoxidase antibodies (MPO). There were 14(17.5%) ANCA-positive LN patients with positive anti-proteinase 3 antibodies (PR3), and 11(13.8%) ANCA-positive patients with double positive antibodies of MPO and PR3. ANCA-positive LN patients had significantly higher serum creatinine [135.5(68.0, 361.8) μmol/L vs 88.0(64.0, 165.0) μmol/L, P=0.004] and blood urea nitrogen [12.35(6.35, 21.18) mmol/L vs 8.60(5.50, 15.70) mmol/L, P=0.026] as well as lower estimated glomerular filtration rate [45.70(13.83, 84.10) ml·min^-1·(1.73 m²)^-1 vs 66.75(38.43, 96.22) ml·min^-1·(1.73 m²)^-1, P=0.001] than ANCA-negative patients (stratified sampling of 160 patients). ANCA-positive LN patients had higher chronicity index than ANCA-negative LN patients [3(2, 7) vs 2(0, 5), P=0.006]. There were statistically significant difference in hemoglobin, serum creatinine and estimated glomerular filtration rate among ANCA-positive group, ANCA-negative group, and MPO-ANCA and PR3-ANCA double positive group. MPO-ANCA and PR3-ANCA double positive LN patients had the lowest hemoglobin and estimated glomerular filtration rate, and highest serum creatinine among the three groups (all P<0.05). Conclusions ANCA-positive LN patients have worse renal function and higher renal histological chronicity index than ANCA-negative LN patients, especially for patients with double positive MPO-ANCA and PR3-ANCA. More stringent monitoring and therapy may be needed in this subgroup of LN patients.

Objective To analyze the incidence and risk factors of acute kidney injury (AKI) in patients undergoing neurosurgery. Methods This study was a single center and retrospective research. The patients hospitalized in the general neurosurgery ward of Xuanwu Hospital, Capital Medical University, due to intracranial tumors and intracranial vascular diseases from January 1, 2017 to December 31, 2020 were enrolled. Demographic, clinical data and laboratory examination results of the selected patients were collected. The patients were divided into AKI group and non-AKI group according to AKI diagnosis criteria, and the differences of clinical parameters and medication between the two groups were compared. Logistic regression analysis method was used to analyze the risk factors of AKI in neurosurgical patients. Results Among 4 509 patients undergoing neurosurgery with age of (51.93±16.03) years old, 2 361 males and 2 148 females, 152 patients (3.37%) had AKI. The incidence of AKI in patients undergoing intracranial tumor surgery was 3.69%(84/2 278), and the incidence of AKI in patients undergoing intracranial cerebrovascular surgery was 3.05%(68/2 231). The length of hospital stay (t=4.897, P<0.001) and operation time (t=5.496, P<0.001) in AKI group were significantly longer than those in non-AKI group. The proportions of diabetes mellitus, preoperative serum creatinine, blood urea nitrogen, glycosylated hemoglobin, lactic acid, fibrinogen, and systolic pressure levels in AKI group were significantly higher than those in non-AKI group (all P<0.05); the hemoglobin level in AKI group was significantly lower than that in non-AKI group (P<0.05). The proportions of patients using angiotensin converting enzyme inhibitors/angiotensinⅡreceptor antagonists, cephalosporins, proton pump inhibitors, mannitol, and nonsteroidal anti-inflammatory drugs in AKI group were also significantly higher than those in non-AKI group (all P<0.05). Multivariate logistic regression analysis results showed that hemoglobin<110 g/L (OR=4.252, 95%CI 1.569-11.527, P=0.004), elevated blood urea nitrogen (OR=1.304, 95%CI 1.139-1.492, P<0.001) and application of nonsteroidal anti-inflammatory drugs (OR=2.342, 95%CI 1.044-5.253, P=0.039) were independent risk factors of AKI in neurosurgical patients. Conclusions The incidence of AKI in patients in neurosurgery general ward is 3.37%. Anemia, elevated blood urea nitrogen and application of nonsteroidal anti-inflammatory drugs are independent risk factors of AKI in patients undergoing neurosurgery.

Objective To investigate the role of survival motor neuron (SMN) gene knockout in mice with cisplatin-induced acute kidney injury (AKI). Methods A mouse model (C57BL/6) of cisplatin-induced AKI was constructed. Twenty male wild type (WT) and SMN^+/- mice weighing 22-24 g were randomly divided into four groups: WT mice with saline injection group (WT vehicle, n=5), SMN^+/- mice with saline injection group (SMN^+/- vehicle, n=5), WT mice with cisplatin injection group (WT cisplatin, n=5) and SMN^+/- mice with cisplatin injection group (SMN^+/- cisplatin, n=5). Mice were injected intraperitoneally with 20 mg/kg cisplatin or 0.9% saline. 72 hours later, the mice were sacrificed, and serum and kidney tissues were collected. The real time PCR and Western blotting were used to measure the expression levels of SMN mRNA and protein. The sarcosine oxidation and urease method were used to measure serum creatinine (Scr) and blood urea nitrogen (BUN) levels. Renal pathologic changes were observed by PAS staining. TUNEL immunofluorescence assay was used to detect the level of apoptosis. Western blotting and immunohistochemistry were used to detect the protein expression levels of apoptosis index poly (ADP-ribose) polymerase (PARP) and endoplasmic reticulum stress index CHOP. Results Compared with WT mice, SMN mRNA and protein expression levels were lower in SMN^+/- mice, and the expression level of SMN mRNA and protein was further decreased after intraperitoneal cisplatin injection (all P<0.05). Compared with WT mice with saline injection group, WT mice with cisplatin injection group had higher levels of Scr, BUN, tubular damage scores, TUNEL positive cell numbers, PARP and CHOP, while the expression levels of above indexes in the SMN^+/- mice with cisplatin injection group were higher than those in the WT mice with cisplatin injection group (all P<0.05). Conclusions SMN gene knockout can aggravate renal pathological damage and apoptosis of renal tubular epithelial cell in cisplatin-induced AKI mice. SMN may be a potential therapeutic target of AKI.