Over the past decade, there has been a dramatic increase in kidney biopsy inadequacy rate. Evaluation of biopsy adequacy by pathology is often not available. This study utilizes a smartphone camera to take a photograph of the biopsy at the bedside, which is then enlarged to allow for distinction between cortex and medulla. The physician performing the procedure, most often a radiologist, can then decide if additional samples are needed. In this study, there was a high agreement rate in the determination of adequacy between pathology (using a dissecting microscope) and radiology (using a smartp ..read more

Early in the COVID-19 pandemic many wondered how COVID-19 would impact kidney function. A collaboration across multiple institutions was formed to study kidney biopsies from COVID-19 patients. This paper analyzes 284 native and transplant kidney biopsies from patients with COVID-19. Compared to a five-year pre-pandemic cohort, native kidney biopsies showed an increase in collapsing glomerulopathy, myoglobin cast nephropathy, and proliferative glomerulonephritis with monoclonal IgG deposits. Over 90% of patients with collapsing glomerulopathy had two APOL1 high-risk alleles, compared to 35% of ..read more

Approximately half of lupus patients have kidney disease, including membranous glomerulopathy. On renal biopsy, immunofluorescence shows granular capillary loop deposits, and holes are seen in the capillary loops on silver stain. Electron microscopy shows subepithelial immune complex deposits. It is important to determine an antigen in these cases, as it can be linked to patient prognosis. The most common antigen seen in membranous lupus nephritis is EXT1/2, followed by NCAM1. This study identified a new target antigen, TGFBR3, seen in approximately 6% of membranous lupus nephritis cases. TGFB ..read more

There's a new membranous lupus nephritis antigen - it's not just EXT1/2! Dr. Rebecca May and Dr. Tiffany Caza discuss neural cell adhesion molecule 1 in Episode 10 of Arkana Advances ..read more

Membranous nephropathy is a leading cause of nephrotic syndrome. On renal biopsy, immunofluorescence shows granular capillary loop deposits, and holes are seen in the capillary loops on silver stain. Electron microscopy shows subepithelial immune complex deposits. A majority of cases have autoantibodies against PLA2R and THSD7A. This study identified a new target antigen, NELL1, which was present in 1.7% of membranous cases. NELL1 can also be detected in the serum of these patients. Approximately 33% of patients with NELL1 have a known malignancy. Patients with successful treatment of the mali ..read more

Nephrocalcinosis is the finding of abundant calcium phosphate deposits within the tubulointerstitium of the kidney. This is a case report of a renal biopsy from an 11 month old male with hypercalcemia and developmental delay, who was found to have nephrocalcinosis. It is a rare diagnosis in infants, and should prompt a genetic workup. Genetic workup revealed a CYP24A1 mutation, which results in a truncated protein. This is a novel mutation in this gene. CYP24A1 is involved in Vitamin D metabolism. It is important to publish these mutations so geneticists can create databases of pathogenic muta ..read more

In patients with chronic kidney disease, toxins normally excreted by the kidney continue to circulate, leading to increased kidney damage. The gut microbiome likely plays a role in this damage and contributes to systemic inflammation. Supplementation with dietary fiber (resistant starch) may prevent this kidney damage. This study uses a mouse model of chronic kidney disease and showed that mice fed resistant starch had significantly less kidney fibrosis. A diet including resistant starch altered the gut microbiome, with changes detected in proteins involved in gut permeability and the inflamma ..read more

This discussion focuses on a review article of crystals seen in renal biopsies. Crystalline nephropathies are often associated with systemic conditions. We discuss calcium based crystals, dysproteinemia-related (such as light chain), crystal storing histiocytosis, crystalglobulin/cryocrystalglobulin, metabolic disorders, and drug associated crystals. We review the appearance of the crystals, their etiology, and the associated prognosis for the patient. This is an excellent synopsis of the most common renal crystals for both trainees and practicing renal pathologists. Read the paper: https://ww ..read more

Dr. May discusses a review article with Dr. Dvanajsack that focuses on renal intratubular casts in Episode 5 of Arkana Advances. Both benign casts, as well as six types of pathologic casts, are addressed ..read more

In Episode 4 of Arkana Advances, Dr. May interviews Dr. Cassol over her recent publication discussing viral-like inclusions in COVID-19 negative renal biopsies detected by electron microscopy ..read more