The KDIGO 2021 Clinical Practice Guideline for the Management of Glomerular Diseases represents the first update to this set of recommendations since the initial set of KDIGO guideline recommendations was published in 2012. The pace of growth in our molecular understanding of glomerular disease has quickened and a number of newer immunosuppressive and targeted therapies have been introduced since the original set of guideline recommendations, making such an update necessary. Despite these updates, many areas of controversy remain. In addition, further updates since the publication of KDIGO 2021 have occurred which this guideline does not encompass. With this commentary, the KDOQI work group has generated a chapter-by-chapter companion opinion article that provides commentary specific to the implementation of the KDIGO 2021 guideline in the United States.

The podocyte is a key cell in maintaining renal filtration barrier integrity. Several recent studies have analyzed the genome and transcriptome in the podocyte at deep resolution. This avenue of \"podocyte-ome\" research was enabled by a variety of techniques, including 1) single-cell transcriptomics, 2) FACS with and without genetically encoded markers, and 3) deep proteomics. However, data across various omics techniques and studies are currently not well integrated with each other. Here, we aimed to establish a common, simplified knowledge base for the mouse podocyte-ome by integrating bulk RNA sequencing, bulk proteomics of FACS-sorted podocytes, and single-cell transcriptomics. Three publicly available datasets of each omics technique from different laboratories were bioinformatically integrated and visualized. Our approach not only revealed conserved processes of podocytes but also sheds light on the benefits and limitations of the used technologies. We identified that high expression of glycan glycosylphosphatidylinositol anchor synthesis and turnover, as well as retinol metabolism, were relatively understudied features of podocytes. In addition, actin-binding molecules were organized in a podocyte-specific manner, as evidenced by differential expression in podocytes compared with other glomerular cells. We compiled a Web-based \"PodIent\" application that illustrates the features of the integrated dataset. This enables user-driven exploratory analysis by querying genes of interest for podocyte identity in absolute and relative quantification while also linking to functional annotation using keywords, Gene Ontology terms, and gene set enrichments. This consensus draft is a first step toward common molecular omics knowledge of kidney cells.NEW & NOTEWORTHY Podocytes are key components of glomerular filtration and are affected in various kidney diseases. Here, we present an integrated, robust definition of molecular identity across proteomic, single-cell transcriptomics, and bulk transcriptomic studies on native mouse podocytes. We created the \"PodIdent\" app, a novel knowledge base promoting access to the presence and expression of specific proteins for podocytes.

During pregnancy, CKD increases both maternal and fetal risk. Adverse maternal outcomes include progression of underlying renal dysfunction, worsening of urine protein, and hypertension, whereas adverse fetal outcomes include fetal loss, intrauterine growth restriction, and preterm delivery. As such, pregnancy in young women with CKD is anxiety provoking for both the patient and the clinician providing care, and because the heterogeneous group of glomerular diseases often affects young women, this is an area of heightened concern. In this invited review, we discuss pregnancy outcomes in young women with glomerular diseases. We have performed a systematic review in attempt to better understand these outcomes among young women with primary GN, we review the studies of pregnancy outcomes in lupus nephritis, and finally, we provide a potential construct for management. Although it is safe to say that the vast majority of young women with glomerular disease will have a live birth, the counseling that we can provide with respect to individualized risk remains imprecise in primary GN because the existing literature is extremely dated, and all management principles are extrapolated primarily from studies in lupus nephritis and diabetes. As such, the study of pregnancy outcomes and management strategies in these rare diseases requires a renewed interest and a dedicated collaborative effort.