Objective: To assess the epidemiological burden and healthcare resource utilization of ANCA-associated vasculitis (AAV) in China using population-based healthcare databases from Beijing and Hainan, and to quantify the contributions of major complications to mortality and direct medical costs.Methods: AAV cases were identified from regional healthcare databases and death registries from 2017 to 2023 using ICD-10 codes and diagnostic terms. Age-standardized prevalence, incidence, mortality, and case-fatality rates were estimated. Healthcare utilization, including outpatient and inpatient costs and readmissions, was described. In the incident cohort, time-dependent Cox proportional hazards models and gamma generalized linear models were used to evaluate the impact of major complications on mortality and costs, and population attributable fractions (PAFs) were calculated.Results: A total of 4,917 patients with AAV were included (mean age, 65.56 years), of whom 30.12% died during the study period. From 2017 to 2023, age-standardized prevalence, incidence, and mortality all increased. In 2023, the age-standardized prevalence in Beijing and Hainan was 10.47 and 2.51 per 100,000, respectively; incidence was 2.94 and 0.75 per 100,000; and mortality was 0.80 and 0.26 per 100,000. Case-fatality rates fluctuated over time, ranging from 1.5%-2.8% in Beijing and 3.0%-7.9% in Hainan. Healthcare utilization were dominated by inpatient care, with mean inpatient and outpatient costs of 7,814.42 ± 14,080.71 and 815.83 ± 1,805.08 (2023 USD), respectively. The 30-day, 90-day, and 1-year readmission rates were 26.86%, 37.31%, and 46.71%. Most severe complications accumulated rapidly within 6 months after diagnosis. End-stage renal disease (ESRD), severe infection, venous thromboembolism (VTE), and interstitial lung disease (ILD) were the major drivers of mortality and costs, with PAFs for mortality of 15.17%, 11.87%, 12.13%, and 14.81%, respectively, and PAFs for direct medical costs of 12.63%, 11.59%, 8.95%, and 4.46%.Conclusion: AAV in China is characterized by high incidence, high mortality, and low prevalence, with healthcare utilization dominated by hospitalization and high readmission rates. Early identification and standardized management of severe complications may reduce both mortality risk and healthcare costs.

Introdução: Patients with childhood-onset frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS) need approved therapies to sustain clinical remission and minimise glucocorticoid burden. B-cell–depleting monoclonal antibodies, like rituximab, have established the pathogenic role of B cells in this condition. Obinutuzumab (obi), a type II anti-CD20 monoclonal antibody, depletes B cells more effectively than rituximab. The INShore study (NCT05627557) assesses obi’s efficacy and safety vs. mycophenolate mofetil (MMF) in children and young adults (aged ≥2-25 years) with childhood-onset FRNS or SDNS. Métodos: Participants in complete remission but at high relapse risk are randomized 1:1 to obi or MMF. Intravenous obi (1000 mg or 20 mg/kg for <45 kg) is infused on Day 1 and Weeks 2, 24, 26. MMF (titrated by Week 4 to 1200 mg/m²/day) is given orally b.i.d until Week 52, after which administration must be discontinued or tapered over the subsequent 3 months. Participants in either arm receiving oral glucocorticoids at randomisation follow a guided taper to achieve a target of 0 mg by Week 8. Relapse is confirmed by first-morning void urine protein-to-creatinine ratio (UPCR) lab testing and defined as: 1) UPCR ≥2 g/g, 2) dipstick urinalysis protein ≥3+ for 3 consecutive days with the most recent UPCR >0.2 g/g, or 3) dipstick urinalysis protein ≥3+ on any single day with edema and UPCR >0.2 g/g. The primary endpoint is the proportion of participants with sustained complete remission at 1 year (first-morning void UPCR ≤0.2 g/g at Week 52). Secondary endpoints include overall relapse-free survival, cumulative glucocorticoid dose, number of relapses, and proportion of participants with sustained complete remission at Week 76. Resultados: INShore is fully enrolled with 85 participants across 32 sites in 9 countries, including 30 (35.3%) females and 55 (64.7%) males; 23 (27.1%) Asian, 14 (16.5%) Black or African American, 47 (55.3%) White, and 1 (1.2%) unknown race; 38 (44.7%) have FRNS and 47 (55.3%) SDNS; 50 (58.8%) received prior non-steroid immunosuppressive therapy. At baseline, mean (SD) age was 9.9 (4.39) years and serum albumin 4.3 (0.42) g/dl; median [IQR] eGFR 120.0 [110.0, 134.0] ml/min/1.73 m2 and UPCR 0.0 [0.0, 0.1] g/g. Discussão e Conclusões: Successful enrollment and diverse demographics provide a robust basis for assessing obi versus MMF. Full results will be available after primary analysis (post-52 weeks completion).

Polymicrobial pulmonary infections, common in immunocompromised patients, often manifest more severe symptoms than monomicrobial infections. Clinical diagnosis delays may lead to mortality, emphasizing the importance of fast and accurate diagnosis for these patients. Metagenomic next-generation sequencing (mNGS), as an unbiased method capable of detecting all microbes, is a valuable tool to identify pathogens, particularly in cases where infections are difficult to diagnosis using conventional methods. A 50-year-old male patient was admitted due to cough, expectoration and dyspnea. CT scan revealed diffuse inflammatory and cavernous lung lesion, and blood examination suggested a polymicrobial infection. However, no etiology was found by routine examination. mNGS of bronchoalveolar lavage fluid(BALF)simultaneously detected the presence of Pneumocystis jirovecii (P.jirovecii), Aspergillus fumigates (A.fumigates), Nocardia farcinica (N.farcinica), Salmonella enterica subsp. enterica (S.enterica subsp. enterica), and cytomegalovirus (CMV). The patient was successfully treated with compound sulfamethoxazole (SMZ-TMP), cefoperazone/sulbactam (SCF), moxifloxacin (MXF), voriconazole (VCZ), and ganciclovir. The patient recovered after two weeks of anti-infection therapy and maintained good health at a six-month follow-up. For immunocompromised patients with multiple infections and atypical symptoms, mNGS emerged as a reliable approach to pathogen detection and guiding antibiotic therapy.

Importance:Both tacrolimus (TAC) and mycophenolate mofetil (MMF) are recommended for children with frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). However, their comparative effectiveness and safety have not been evaluated through randomized clinical trials. Objective:To compare the effectiveness and safety of TAC and MMF in children with FRNS or SDNS. Design, Setting, and Participants:In this multicenter, open-label randomized clinical trial conducted at 12 pediatric nephrology centers across China, 270 children aged 2 to 18 years with FRNS or SDNS were allocated at a 1:1 ratio to treatment with either TAC or MMF. The study was conducted from November 2019 to July 2023, and data analysis was completed from July 2023 to March 2024. Intervention:Patients received either TAC (0.025-0.050 mg/kg, orally twice daily) or MMF (10-15 mg/kg, orally twice daily) for 1 year, along with a tapering regimen of steroids. Main Outcomes and Measures:The primary end point was 1-year relapse-free survival. Relapse frequency, cumulative steroid dosage, and safety profiles were also evaluated. Results:A total of 292 patients from 12 care centers were assessed for eligibility, and 270 patients were randomized to receive either TAC (n = 135) or MMF (n = 135). Among 270 patients, median (IQR) age was 6.91 (4.25-9.96) years, and 70 patients (25.9%) were female. Compared with MMF, the 1-year relapse-free survival rate in the TAC group was 1.86-fold higher (hazard ratio [HR], 2.86; 95% CI, 1.79-4.76; P < .001) in the intention-to-treat analysis. This difference was also significant after adjusting for the per-protocol analysis (HR, 2.78; 95% CI, 1.72-4.55; P < .001). The mean (SD) time to first relapse was significantly longer in the TAC group (323.99 [98.33] days) compared to the MMF group (263.21 [132.84] days). Furthermore, the TAC group showed a lower annual relapse rate than the MMF group (17.78% vs 41.48%) and required a significantly lower mean (SD) cumulative steroid dose (0.22 [0.10] mg/kg/day vs 0.34 [0.22] mg/kg/day). The safety profile was similar in both groups. Conclusions and Relevance:In this randomized clinical trial, compared with MMF, a 1-year course of TAC therapy significantly extended the period of relapse-free survival in children with FRNS or SDNS. Trial Registration:ClinicalTrials.gov Identifier: NCT04048161.

Mycobacterium abscessus exhibits intrinsic resistance to most antibiotics, hence leading to infections that are difficult to treat. To address this issue, the identification of new molecular targets is essential for the development or repositioning of therapeutic agents. This study demonstrated that the MAB_2362-knockout strain, Mab(Delta 2362), became significantly susceptible to a range of antibiotics, not only in vitro but also exhibited susceptibility to rifabutin, bedaquiline, and linezolid in vivo. While the bacterial burden of the wild-type M. abscessus (Mab(Wt)) increased by over 1 log(10) CFU/lung in a murine infection model 16 days post-infection, that of Mab(Delta 2362) strain decreased by more than 1 log(10) CFU/lung, which suggests that the disruption leads to attenuation. Bioinformatics analysis revealed that MAB_2362 shares the highest similarity (41.35%) with SteA, a protein known to influence cell division in Corynebacterium glutamicum, suggesting that MAB_2362 might be involved in cell division. Mab(Delta 2362) cells exhibited a median length of 2.62 mu m, which was substantially longer than the 1.44 mu m recorded for Mab(Wt) cells. Additionally, multiple cell division septa were observed in 42% of Mab(Delta 2362) cells, whereas none were seen in Mab(Wt) cells. An ethidium bromide uptake assay further suggested a higher cell envelope permeability in Mab(Delta 2362) compared to Mab(Wt). Collectively, these findings underscore the role of MAB_2362 in intrinsic resistance and virulence of M. abscessus possibly through the regulation of cell division. Thus, MAB_2362 emerges as a promising candidate for targeted interventions in the pursuit of novel antimicrobials against M. abscessus.

Objectives Amikacin is crucial for treating Mycobacterium abscessus (Mab) infections, with resistance primarily attributed to rrs gene mutations. The correlation between specific mutations and amikacin susceptibility, along with the associated fitness cost, requires further investigation.Methods We isolated spontaneous amikacin-resistant mutants in vitro and identified their mutation sites in the rrs gene via Sanger sequencing, which were then compared with existing reports. Using CRISPR/Cas12a-assisted recombineering, we engineered Mab strains with specific rrs mutations. The growth rate and fitness costs in vitro were evaluated, in conjunction with drug susceptibility testing to determine the relationship between rrs mutations and amikacin resistance.Results The mutation frequency of Mab for amikacin resistance ranged from 4.68 x 10(-7) to 9.38 x 10(-9). Three rrs mutation sites (A1375G, C1376T, G1458T) were identified, with A1375G being the most prevalent. Two additional sites, T1373A and T1465A, have been reported previously but not detected in this study. The five gene-edited strains demonstrated resistance to amikacin and cross-resistance to other aminoglycosides, and all exhibited slower in vitro growth rates than the wild-type Mab. Competitive experiments revealed that T1373A and T1465A have high fitness costs, while C1376T and G1458T have weak fitness costs and A1375G shows no fitness costs.Conclusions Our findings confirm that rrs mutations confer high-level amikacin resistance, with the limited mutation spectrum in clinical isolates possibly linked to higher spontaneous mutation frequency and lower fitness costs.

Mycobacterium abscessus (Mab) poses serious therapeutic challenges, largely due to its intrinsic resistance to many antibiotics. The development of targeted therapeutic strategies necessitates the identification of bacterial factors that contribute to its reduced susceptibility to antibiotics and/or to the killing by its host cells. In this study, we discovered that Mab strains with disrupted mtrA, mtrB or both, or a gene-edited mtrA encoding MtrA with Tyr102Cys mutation, exhibited highly increased sensitivity to various drugs compared to the wild-type Mab. In a murine model, three antibiotics inactive against the wild-type Mab demonstrated efficacy against the mtrA and mtrB knockout strains, significantly reducing pulmonary bacterial burdens compared to untreated controls. Notably, the virulence of all the mtrA, mtrB and mtrAB knockout mutants was highly diminished, evidenced by a reduced bacterial load in mouse lungs, undetectable level in spleens, and defective growth in macrophage RAW264.7. Morphological analysis revealed elongated cell length and multiple septa in knockout strains, suggesting both MtrA and MtrB regulate cell division of Mab. Furthermore, the absence of mtrA, mtrB or both significantly increased cell envelope permeability and reduced biofilm formation. Transcriptome sequencing showed altered expression levels of multiple genes related to plasma membrane, fatty acid metabolism and biosynthesis pathways in wild-type Mab and mtrA knockout strain. In summary, this study suggests that MtrA and MtrB play a crucial role in the intrinsic resistance and virulence of Mab by affecting cell division and altering cell permeability. Consequently, MtrA and MtrB represent promising targets for the discovery of anti-Mab drugs.

Introduction:Large-scale trials showed positive outcomes of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in adults with chronic kidney disease (CKD). Whether the use of SGLT2i is safe and effective in patients with the common hereditary CKD Alport syndrome (AS) has not yet been investigated specifically in larger cohorts. Methods:This observational, multicenter, international study (NCT02378805) assessed 112 patients with AS after start of SGLT2i. The study's primary end point was change of albuminuria in albumin/g creatinine from the start of therapy. Results:Compared to randomized trials investigating the effect of SGLT2i in CKD, the adult patients in this study were younger (aged 38 ± 14 years) and had a better estimated glomerular filtration rate (eGFR, 63 ± 35 ml/min per 1.73 m2; n = 98). Maximum follow-up was 32 months. Compared to baseline, at the first 3 follow-up visits (months 1 to 3, 4 to 8, and 9 to 15) after initiation of SGLT2i therapy, a significant reduction of albuminuria in mg albumin/g creatinine (>30%) was observed. Mean loss of eGFR was 9 ± 12 ml/min per 1.73 m2 almost 1 year after initiation of SGLT2i therapy (n = 35). At a total of 71 patient-years at risk, 0.24 adverse events (AEs) per patient-year on SGLT2i were reported. Conclusion:This study indicates that, additive to renin-angiotensin system (RAS)-inhibition (RASi), SGLT2i have the potential to reduce the amount of albuminuria in patients with AS. Future studies are needed to investigate the long-term effects of SGLT2i on CKD progression in patients with AS to assess whether the observed reduction in albuminuria translates to a delay in kidney failure (KF).

Introduction: The calcineurin inhibitor cyclosporine A (CsA) has been shown to effectively reduce proteinuria. However, its precise mechanism is still not fully understood. Our previous study showed that CsA reduced proteinuria by directly stabilizing the foot process (FP) cytoskeletal structure via cofilin-1, suggesting that synaptopodin, a podocyte-specific actin protein, is not the sole target of CsA in podocytes. Methods: In this study, we established an adriamycin (ADR)-induced nephropathy rat model and a cultured podocyte injury model. We employed Western blotting and immunofluorescence techniques to assess the expression and distribution of transgelin, Krüppel-like factor-4 (KLF-4), nephrin, and synaptopodin. Results: We observed a significant increase in proteinuria levels accompanied by loss of normal FP structure in the ADR-induced nephropathy rat model. The levels of the actin cross-linking protein transgelin were increased significantly, while those of the podocyte-specific molecules nephrin and synaptopodin were decreased in vivo. Treatment with CsA effectively reduced proteinuria while restoring FP effacement stability in ADR-induced nephropathy models and restoring the expression of transgelin, nephrin, and synaptopodin both in vivo and in vitro. Furthermore, CsA treatment dose-dependently decreased transgelin levels while significantly increasing KLF-4 expression in injured podocytes. In addition, CsA failed to downregulate transgelin when KLF-4 was specifically knocked down. Conclusion: Our findings suggest that CsA protects against podocyte injury by downregulating abnormally high levels of transgelin via upregulation of KLF-4 expression.

Background Nephritis is a common manifestation of IgA vasculitis and is morphologically indistinguishable from IgA nephropathy. While MEST-C scores are predictive of kidney outcomes in IgA nephropathy, their value in IgA vasculitis nephritis has not been investigated in large multiethnic cohorts. Methods Biopsies from 262 children and 99 adults with IgA vasculitis nephritis ( N =361) from 23 centers in North America, Europe, and Asia were independently scored by three pathologists. MEST-C scores were assessed for correlation with eGFR/proteinuria at biopsy. Because most patients ( N =309, 86%) received immunosuppression, risk factors for outcomes were evaluated in this group using latent class mixed models to identify classes of eGFR trajectories over a median follow-up of 2.7 years (interquartile range, 1.2–5.1). Clinical and histologic parameters associated with each class were determined using logistic regression. Results M, E, T, and C scores were correlated with either eGFR or proteinuria at biopsy. Two classes were identified by latent class mixed model, one with initial improvement in eGFR followed by a late decline (class 1, N =91) and another with stable eGFR (class 2, N =218). Class 1 was associated with a higher risk of an established kidney outcome (time to ≥30% decline in eGFR or kidney failure; hazard ratio, 5.84; 95% confidence interval, 2.37 to 14.4). Among MEST-C scores, only E1 was associated with class 1 by multivariable analysis. Other factors associated with class 1 were age 18 years and younger, male sex, lower eGFR at biopsy, and extrarenal noncutaneous disease. Fibrous crescents without active changes were associated with class 2. Conclusions Kidney outcome in patients with biopsied IgA vasculitis nephritis treated with immunosuppression was determined by clinical risk factors and endocapillary hypercellularity (E1) and fibrous crescents, which are features that are not part of the International Study of Diseases of Children classification.

Early-onset polyhydramnios during pregnancy can be caused by X-linked transient antenatal Bartter syndrome. Most of the reported cases were molecularly diagnosed after birth, whereas few cases were diagnosed in the fetus period. We received a pregnant woman who had polyhydramnios detected by ultrasound imaging at 25 weeks of gestation, and treated with magnesium sulfate, indomethacin and an amnioreduction at 30 weeks of gestation, whereas amniotic fluid decreased spontaneously since 32 weeks of gestation. Prenatal molecular testing showed the fetus carried MAGED2 hemizygous variant c.967C>T [p. (Asp323*)] inherited from the mother. The preterm boy did not present with polyuria and electrolytes and acid-base imbalance in the early neonatal period, and had good development without polyuria at the age of 20 months. We presented the phenotypes of a Chinese case with a prenatal diagnosis of X-linked transient antenatal Bartter syndrome and his response to prenatal indomethacin treatment. Early identification of the condition helps to provide appropriate prenatal genetic counseling and postnatal management.

Introduction: Genetic diagnosis of Alport syndrome (AS), which results from pathogenic variants in COL4A3, COL4A4, or COL4A5 genes, is hindered by large numbers of unclassified variants detected using next-generation sequencing (NGS). We examined the impact on splicing of variants of uncertain signifi- cance in COL4A3 to COL4A5.Methods: Nine unrelated patients with clinical diagnosis or suspicion of AS were enrolled according to the criteria. Their clinical and genetic data were collected. Blood and urine samples were obtained from the patients and their family members. Sanger sequencing was used to confirm the 9 COL4A3 to COL4A5 unclassified variants identified by NGS. COL4A3 to COL4A5 mRNAs from urine were analyzed using targeted reverse transcription polymerase chain reaction and direct sequencing.Results: Nine COL4A3 to COL4A5 unclassified variants were found to alter mRNAs splicing. Skipping of an exon or an exon fragment was induced byvariants COL4A3 c.828 thorn 5G>A; COL4A4 c.3506-13_3528del; and COL4A5 c.451A>G (p. [Ile151Val]), c.2042-9 T>G, c.2689 G>C (p. [Glu897Gln]) and c.1033-10_1033-2delGGTAATAAA. Retention of an intron fragment was caused by variants COL4A3 c.3211-30G>T, and COL4A5 c.4316-20T>A and c.1033-10 G>A, respectively. The 9 families in this study obtained genetic diagnosis of AS, including 3 with autosomal recessive AS and 6 with X-linked AS.Conclusions: Our findings demonstrate that urine mRNA analysis facilitates the identification of abnormal splicing of unclassified variants in Alport genes, which provides evidence of routine use of RNA analysis to improve genetic diagnosis of AS.