SARS-CoV-2 Infection in Patients on Dialysis: Incidence and Outcomes in the Lazio Region, Italy

Patients with end-stage kidney disease represent a frail population and might be at higher risk of SARS-CoV-2 infection. The Lazio Regional Dialysis and Transplant Registry collected information on dialysis patients with a positive swab. The study investigated incidence of SARS-CoV-2 infection, mortality and their potential associated factors in patients undergoing maintenance hemodialysis (MHD) in the Lazio region. Method: The occurrence of infection was assessed among MHD patients included in the RRDTL from 1 March to 30 November 2020. The adjusted cumulative incidence of infection and mortality risk within 30 days of infection onset were estimated. Logistic and Cox regression models were applied to identify factors associated with infection and mortality, respectively. Results: The MHD cohort counted 4942 patients; 256 (5.2%) had COVID-19. The adjusted cumulative incidence was 5.1%. Factors associated with infection included: being born abroad, educational level, cystic renal disease/familial nephropathy, vascular disease and being treated in a dialysis center located in Local Health Authority (LHA) Rome 2. Among infected patients, 59 (23.0%) died within 30 days; the adjusted mortality risk was 21.0%. Factors associated with 30-day mortality included: age, malnutrition and fever at the time of swab. Conclusions: Factors associated with infection seem to reflect socioeconomic conditions. Factors associated with mortality, in addition to age, are related to clinical characteristics and symptoms at the time of swab.

Metabolomics Profiling of Cystic Renal Disease towards Biomarker Discovery

Cystic renal disease (CRD) comprises a heterogeneous group of genetic and acquired disorders. The cystic lesions are detected through imaging, either incidentally or after symptoms develop, due to an underlying disease process. In this study, we aim to study the metabolomic profiles of CRD patients for potential disease-specific biomarkers using unlabeled and labeled metabolomics using low and high-resolution mass spectrometry (MS), respectively. Dried-blood spot (DBS) and serum samples, collected from CRD patients and healthy controls, were analyzed using the unlabeled and labeled method. The metabolomics profiles for both sets of samples and groups were collected, and their data were processed using the lab’s standard protocol. The univariate analysis showed (FDR p < 0.05 and fold change 2) was significant to show a group of potential biomarkers for CRD discovery, including uridine diphosphate, cystine-5-diphosphate, and morpholine. Several pathways were involved in CRD patients based on the metabolic profile, including aminoacyl-tRNA biosynthesis, purine and pyrimidine, glutathione, TCA cycle, and some amino acid metabolism (alanine, aspartate and glutamate, arginine and tryptophan), which have the most impact. In conclusion, early CRD detection and treatment is possible using a metabolomics approach that targets alanine, aspartate, and glutamate pathway metabolites.

Genetic Architecture of Childhood Kidney and Urological Diseases in China

Kidney disease is manifested in a wide variety of phenotypes, many of which have an important hereditary component. To delineate the genotypic and phenotypic spectrum of pediatric nephropathy, a multicenter registration system is being implemented based on the Chinese Children Genetic Kidney Disease Database (CCGKDD). In this study, all the patients with kidney and urological diseases were recruited from 2014 to 2020. Genetic analysis was conducted using exome sequencing for families with multiple affected individuals with nephropathy or clinical suspicion of a genetic kidney disease owing to early-onset or extrarenal features. The genetic diagnosis was confirmed in 883 of 2256 (39.1%) patients from 23 provinces in China. Phenotypic profiles showed that the primary diagnosis included steroid-resistant nephrotic syndrome (SRNS, 23.5%), glomerulonephritis (GN, 32.2%), congenital anomalies of the kidney and urinary tract (CAKUT, 21.2%), cystic renal disease (3.9%), renal calcinosis/stone (3.6%), tubulopathy (9.7%), and chronic kidney disease of unknown etiology (CKDu, 5.8%). The pathogenic variants of 105 monogenetic disorders were identified. Ten distinct genomic disorders were identified as pathogenic copy number variants (CNVs) in 11 patients. The diagnostic yield differed by subgroups, and was highest in those with cystic renal disease (66.3%), followed by tubulopathy (58.4%), GN (57.7%), CKDu (43.5%), SRNS (29.2%), renal calcinosis /stone (29.3%) and CAKUT (8.6%). Reverse phenotyping permitted correct identification in 40 cases with clinical reassessment and unexpected genetic conditions. We present the results of the largest cohort of children with kidney disease in China where diagnostic exome sequencing was performed. Our data demonstrate the utility of family-based exome sequencing, and indicate that the combined analysis of genotype and phenotype based on the national patient registry is pivotal to the genetic diagnosis of kidney disease.

Acquired cystic renal disease in hemodialysis patients.

Objectives: Acquired cystic renal disease is known complication of End stage renal disease and hemodialysis and is also a precursor to renal cell carcinoma in patients who are on long term maintenance hemodialysis. Study Design: Cross Sectional study. Setting: Bahawal Victoria Hospital, Bahawalpur-Pakistan. Period: Jan 2019 to June 2019. Material & Methods: Patients on maintenance hemodialysis were evaluated using ultrasound for acquired cystic renal disease. Results: The study included 220 patients who were on maintenance hemodialysis. The male to female ratio was 2.01:1. Most common causes of renal failure were Diabetes Mellitus and Renal stone Disease (22.3%) each. Acquired cystic renal disease was found in 45 (20.5%). The difference of frequency of acquired cystic renal disease was statistically significant in age groups & anemia. Conclusions: Acquired cystic renal disease is common complication of End stage renal disease and maintenance hemodialysis. Regular monitoring with ultrasound needs to be done for those patients who are on maintenance hemodialysis for more than 3 years.

Clinical and Pathological Features of a Newborn With Compound Heterozygous ANKS6 Variants

We report a term female infant born to nonconsanguineous parents who presented with renal failure at birth, hypothyroidism, cholestasis, and progressive cardiac dysfunction. Multigene next-generation sequencing panels for cholestasis, cardiomyopathy, and cystic renal disease did not reveal a unifying diagnosis. Whole exome sequencing revealed compound heterozygous pathogenic variants in ANKS6 (Ankyrin Repeat and Sterile Alpha Motif Domain Containing 6), which encodes a protein that interacts with other proteins of the Inv compartment of cilium ( NEK8, NPHP2/INVS, and NPHP3). ANKS6 has been shown to be important for early renal development and cardiac looping in animal models. Autopsy revealed cystic renal dysplasia and cardiomyocyte hypertrophy, disarray, and focal necrosis. Liver histology revealed cholestasis and centrilobular necrosis, which was likely a result of progressive cardiac failure. This is the first report of compound heterozygous variants in ANKS6 leading to a nephronopthisis-related ciliopathy-like phenotype. We conclude that pathogenic variants in ANKS6 may present early in life with severe renal and cardiac failure, similar to subjects with variants in genes encoding other proteins in the Inv compartment of the cilium.