Freely Filtered, a NephJC Podcast

Bypass surgery continues to be the laboratory where we test the most innovative ideas on the prevention of AKI

The Filtrate

Joel Topf @kidney_boy

Swapnil Hiremath @hswapnil.medsky.social

Vipin Varghese

Sophia Ambruso

Special Guests

Rahul Ganatra Deputy Editor NEJM Clinician. https://clinician.nejm.org/editors/AU3406

Jay Koyner Professor of Medicine, University of Chicago. https://www.uchicagomedicine.org/find-a-physician/physician/jay-koyner

Editing

Vipin Varghese

The Kidney Connection written and performed by Timothy Yau

Show Notes

Back to the Future: https://youtu.be/BDuZqYeNiOA?is=r-RE2DgIDBazRAlW

Amino Acids for AKI: The PROTECTION Study NephJC: Trial by Combat: Do Amino Acids provide PROTECTION to the Kidneys?

In 2016 the FDA posted a warning that SGLT2i could induce AKI. This Nature Reviews Nephrology explores possible mechanisms for the AKI: Acute kidney injury from SGLT2 inhibitors: potential mechanisms https://www.nature.com/articles/nrneph.2016.159

But by 2019 the SMART-C Collaboration was looking at the risk of AKI in the large RCTs and found Flozins to be protective: SGLT2 inhibitors for the prevention of kidney failure in patients with type 2 diabetes: a systematic review and meta-analysis. https://www.thelancet.com/journals/landia/article/PIIS2213-8587(19)30256-6/abstract

If you are actually looking for the best data you should look at the updated meta-analysis from 2025 which extends the findings to patients with and without diabetes and to patients with and without CKD: SGLT2 Inhibitors and Kidney Outcomes by Glomerular Filtration Rate and Albuminuria https://pmc.ncbi.nlm.nih.gov/articles/PMC12595549/

2012 KDIGO AKI Guidelines: https://kdigo.org/wp-content/uploads/2016/10/KDIGO-2012-AKI-Guideline-English.pdf

The 2025/2026 AKI Draft guidelines: https://kdigo.org/wp-content/uploads/2026/03/KDIGO-2026-AKI-AKD-Guideline-Public-Review-Draft-March-2026.pdf

Meta-analysis of frusemide to prevent or treat acute renal failure https://www.bmj.com/content/early/2005/12/31/bmj.38902.605347.7C

Euglycemic Diabetic Ketoacidosis: A Potential Complication of Treatment With Sodium–Glucose Cotransporter 2 Inhibition https://diabetesjournals.org/care/article-abstract/38/9/1687/37246/Euglycemic-Diabetic-Ketoacidosis-A-Potential

Topic of this podcast, the MERCURI-2 trial: Dapagliflozin and Acute Kidney Injury Following Cardiac Surgery https://jamanetwork.com/journals/jama/article-abstract/2852324 | NephJC: Too sweet to be true? Prophylactic SGLT2 inhibitors before cardiac surgery https://www.nephjc.com/news/2026/8/18/mercuri2

MERCURI-1 Pilot trial is described here. Looks like it was only published as a pre-print. The first link provides a glimpse at MERCURI-3
https://abrahamhulst.com/research/mercuri-1/

https://www.medrxiv.org/content/10.1101/2024.03.27.24304998v1.full.pdf

Vipin Varghese used to believe in the urinalysis: Diagnostic Utility of Serial Microscopic Examination of the Urinary Sediment in Acute Kidney Injury https://pubmed.ncbi.nlm.nih.gov/35373012/

MERCURI-2 in ClinicalsTrials.gov: proMoting Effective Renoprotection in Cardiac sURgery Patients by Inhibition of SGLT-2 (MERCURI-2)   https://clinicaltrials.gov/study/NCT05590143

Roger Rodby’s 4 favortite equations in Nephrology from Channel Your Enthusioasm: https://pca.st/episode/abff985f-6a87-41f9-bcc9-80b8a85c2441?t=3257.0

IDEAL ICU Timing of Renal-Replacement Therapy in Patients with Acute Kidney Injury and Sepsis https://www.nejm.org/doi/full/10.1056/NEJMoa1803213?referrer=https%3A%2F%2Fwww.google.com%2F

Rethinking the definition of oliguria: Identification of an optimal threshold to define oliguria in critically ill patients: an observational study https://pubmed.ncbi.nlm.nih.gov/37254158/

Editorial on MERCURI-2 in JAMA by Wolfgang Winkelmayer and  Glenn Chertow https://jamanetwork.com/journals/jama/fullarticle/2852331

Tubular Secretion

Swapnil Spider Noire Amazon Prime

Sophia Bernadoodle via Starlight Bernadoodle https://starlightbernedoodles.com

Rahul Derry Girls on Netflix

Vipin Tennis Cincinnati Open and the US Open. The death of the one handed backhand.

Jay Slow Horses on Apple TV and Adults on Hulu

Joel Silo season three. Mountain biking.

Please give 🙏🏽 here: https://www.nephjc.com/news/2026/9/8/nephjc-fall-pledge-drive

The Filtrate

Joel Topf @kidney_boy

Swapnil Hiremath @hswapnil.medsky.social

Natalie Freidin Program director at Medical University of South Carolina

AC @medpeedskidneys.bsky.social

Special Guests

Fernando Fervenza Professor of Medicine, The Mayo Clinic

Editing

Vip Vergues

The Kidney Connection written and performed by Timothy Yau

Show Notes

MENTOR NephJC | NEJM | Freely Filtered episode 7

PLA2r in 2009 M-Type Phospholipase A2 Receptor as Target Antigen in Idiopathic Membranous Nephropathy NEJM

MAJESTY NephJC | NEJM Obinutuzumab or Tacrolimus in Primary Membranous Nephropathy

Giuseppe Remuzzi discovers rituximab works in primary membranous. Rituximab for idiopathic membranous nephropathy The Lancet 2002

Fervenza’s 15-person study of Rituximab treatment of idiopathic membranous nephropathy Kidney International 2008.

Larry Beck’s NEJM PLA2r study M-Type Phospholipase A2 Receptor as Target Antigen in Idiopathic Membranous Nephropathy NEJM 2009

2011 (not 2010) JASN paper where using banked serum from two prior rituximab studies in membranous nephropathy, Beck and Fervenza showed that declines in anti-PLA2R antibodies preceded reductions in proteinuria and predicted subsequent clinical remission, establishing the concept that immunologic remission precedes clinical remission. Rituximab-Induced Depletion of Anti-PLA2R Autoantibodies Predicts Response in Membranous Nephropathy PubMed

The National Institute of Animal Health…a Fervenza fiction

Robert A. Star, M.D. NIH

Daniel C. Cattran, M.D. NephCure

Tubular Secretions

Swap do not go to see Mandalorian and Grogu or Supergirl

AC doing nothing

Natalie The Wealth Ladder by Nick Maggiulli (amazon)

Fernando South Portugal and GlomCon Hawaii

Joel The Boundary Waters Canoe Area

The Filtrate

Joel Topf@kidney_boy

Vipin Verghese@vipvargh.bsky.social

Nayan Arora @captainchloride

Special Guests

David Goldfarb Professor of Medicine, NYU (COI)

Megan Prochaska Assistant professor of medicine at University of Chicago

John Asplin Medical Director Consultant LithoLink (Twitter)

Editing

Anna Gaddy

The Kidney Connection written and performed by Timothy Yau

Show Notes

Kidney Treks, University of Chicago. For medical students.

The Push Trial: Prevention of urinary stones with hydration: a randomised clinical trial of an adherence intervention NephJC Short | The Lancet

Charlie Pak trial showing increased urine volume reduced risk of kidney stones. Evidence justifying a high fluid intake in treatment of nephrolithiasis PubMed

The Borghi Trial: Urinary volume, water and recurrences in idiopathic calcium nephrolithiasis: a 5-year randomized prospective study PubMed

Medical Management of Kidney Stones: AUA Guideline (2026)

Weird little trial Asplin mentioned with amlodipine. But it was actually verapami. By Kemal Sarical: The effect of calcium channel blockers on stone regrowth and recurrence after shock wave lithotripsy PubMed

Borghi’s other giant study in kidney stones: Comparison of Two Diets for the Prevention of Recurrent Stones in Idiopathic Hypercalciuria NEJM

The No Stone Trial: Hydrochlorothiazide and Prevention of Kidney-Stone Recurrence NephJC | NEJM

Gary Curhan epidemiologic data from the Nurses Health Study and the Health Professionals Follow-up Study: Twenty-four-hour urine chemistries and the risk of kidney stones among women and men PubMed

Gary Curhan epidemiologic data on sugar sweetened beverages and risk of kidney stones. Soda and other beverages and the risk of kidney stones PubMed

Eric Topol’s tweet:

NephJC in 2014 on the ACP Kidney Stone Guidelines NephJC

Goldfarb’s scathing editorial on said guidelines, not on NephJC as I said but, on Fred Coe’s website at the University of Chicago. Link

Tubular Secretions

Nayan: Shrinking on Apple TV Wikipedia

David: The deaths of Sonny Rollins (Wikipedia) and James Blood Ulmer (Wikipedia)

Megan: Sri Lanka for travel (National Geographic)

Vipin: Memory Eternal: Living with Grief as Orthodox Christians (Amazon)

John: A History of Rock Music in 500 Songs (Link) Patty Smith’s memoir, Just Kids (Amazon)

Joel: This is How You Lose The War by Amal El-Mohtar and Max Gladstone (Amazon) for the second time, and Acquired PodCast (Link)

The Filtrate

Joel Topf kidneyboy.bsky.social

Swapnil Hiremath @hswapnil.medsky.social

Natalie Freidin Program director at Medical University of South Carolina

Sophia Ambruso @sophia_kidney

AC @medpeedskidneys.bsky.social

Special Guests

Carla Nester, Professor of Medicine, Professor of Pediatrics, University of Iowa. Senior author of Valiant

Editing

Natalie Freidin

The Kidney Connection written and performed by Timothy Yau

Show Notes

Trial of Pegcetacoplan in C3 Glomerulopathy and Immune-Complex MPGN NEJM | NephJC

Tubular Secretions

Swapnil: City of Last Chances by Adrian Tchaikovsky (Amazon)

Natalie: Heated Rivalry, the books by Rachel Reid

Carla: Rowing and gold fiber embroidery

AC: Audiobooks, that are appropriate for children: The Giver and Tuck Everlasting

Sophia: Greeking Out podcast and the Wheel of Time by Robert Jordan (Wikipedia)

Joel: This is How You Lose The War by Amal El-Mohtar and Max Gladstone (Amazon)

The Filtrate

Joel Topf kidneyboy.bsky.social

Swapnil Hiremath @hswapnil.medsky.social

Pedro Teixeira @nephcrit.bsky.social

Special Guests

Ewout J. Hoorn, Professor of Medicine Erasmus MC, Netherlands. One of the primary authors.

Harish Seethapathy, Assistant physician at Massachusetts General Hospital

Editing

Vipin Verghese

The Kidney Connection written and performed by Timothy Yau

Show Notes

A Randomized Trial of Targeted Hyponatremia Correction in Hospitalized Patients in NEJM Evidence, in PubMed, in NephJC

Seethapathy: Severe Hyponatremia Correction, Mortality, and Central Pontine Myelinolysis in NEJM Evidence

MacMillan: Osmotic Demyelination Syndrome in Patients Hospitalized with Hyponatremia in NEJM Evidence

SALSA: Risk of Overcorrection in Rapid Intermittent Bolus vs Slow Continuous Infusion Therapies of Hypertonic Saline for Patients With Symptomatic Hyponatremia: The SALSA Randomized Clinical Trial in JAMA Internal Medicine

SALT 1 and 2: Tolvaptan, a Selective Oral Vasopressin V2-Receptor Antagonist, for Hyponatremia in NEJM

Hyponatremia registry: Current treatment practice and outcomes. Report of the hyponatremia registry in Kidney International

The Richard Sterns’ article on the lower mortality with more severe hyponatremia: Mortality and Serum Sodium: Do Patients Die from or with Hyponatremia? in CJASN

The European Hyponatremia Guidelines: Clinical practice guideline on diagnosis and treatment of hyponatraemia in The European Journal of Endocrinology

The American Hyponatremia Guidelines: Diagnosis, Evaluation, and Treatment of Hyponatremia: Expert Panel Recommendations in American Journal of Medicine

Treating hyponatremia: damned if we do and damned if we don't by Tom Berl in Kidney International

Prospective (clamp) versus reactive (rescue) DDAVP in hyponatremia: Safety and efficacy of proactive versus reactive administration of desmopressin in severe symptomatic hyponatremia: a randomized controlled trial in Nature Scientific Reports and as covered in PBFluids

Helbert Rondon’s RCT of urea Urea for Chronic Hyponatremia on ClinicalTrials.gov

Tubular Secretions

Swapnil: Catfishing on CatNet: A Novel by Naomi Kritzer (Amazon)

Harish: Disney Cruise

Edward: Flesh: A Novel (Booker Prize Winner) by David Szalay (Amazon)

Pedro: Scrubs reboot (IMDB)

Joel: KIDNEYcon

The Filtrate

Joel Topf kidneyboy.bsky.social

Special Guests

Dr. Samir Parikh, President of the American Society of Nephrology

Prof. Donal Reddan, President, Irish Nephrology Society

Prof. Catherine Godson

Editing

Joel Topf

The Kidney Connection written and performed by Timothy Yau

Show Notes

Tubular Secretions

Joel Topf, the Dublin Port Greenway Link

Catherine Godson: never heard of the Dublin Port Greenway

Samir Parikh: Trinity College Dublin and specifically the Eavan Boland Library, named after the Irish poet.

Donal Reddan: Something about rugby

The Filtrate

Joel Topf kidneyboy.bsky.social

Pedro Teixeira @nephcrit.bsky.social

Nayan Arora @captainchloride.bsky.social

Anna Gaddy @annagaddy.bsky.social

Swapnil Hiremath @hswapnil.medsky.social and on LinkedIn

Special Guests

Ian McCoy, MD @NephroNinja study author and UCSF

Chi-yuan Hsu Senior author and Chief of the Division of Nephrology at UCSF

Samuel Silver Associate Professor at Queens University in Canada

Editing

Vipin Verghese and Joel Topf

Show Notes

NephJC Discusion: Dialyze Less, Recover More? AKI’s Chance to Get LIBERATE-D

Manuscript: A Conservative Dialysis Strategy and Kidney Function Recovery in Dialysis-Requiring Acute Kidney InjuryThe Liberation From Acute Dialysis (LIBERATE-D) Randomized Clinical Trial JAMA | PubMed

Ben’s pilot study: RAD-AKI Pilot study: Recovery After Dialysis-Requiring Acute Kidney Injury (RAD-AKI) (ClinicalTrials.gov)

STARRT-AKI NephJC

Editorial in JAMA: A-E-I-O-U and Sometimes Why—Dialysis in Acute Kidney Injury (JAMA)

What Is Dialytrauma? (Nephrology Times)

How Fragile Are the Results of a Trial? The Fragility Index (PubMedCentral)

Shiffl Trial: Daily Hemodialysis and the Outcome of Acute Renal Failure (NEJM)

AKIKI: Initiation Strategies for Renal-Replacement Therapy in the Intensive Care Unit (NEJM)

AKIKI2: How Late it was, How Late! (NephJC)

Sam Silver’s study: Promoting Kidney Recovery After Acute Kidney Injury Receiving Dialysis (Recover-AKI) (ClinicalTrial.Gov)

Marie Kondo (Wikipedia)

Tubular Secretions

Swap: The smutty dragon novels of novels of Rebecca Yarros (Wikipedia) Specifically The Empyrean series

Anna: Brisket recipes

Pedro: The Naked Gun (Wikipedia) with Liam Neeson

Ian: ASN Kidney Health Guidance on the Outpatient Management of Patients with Dialysis-Requiring Acute Kidney Injury (PubMed) he really doesn’t get Tubular Secretions.

Nayan: Tilt: A Novel by Emma Pattee (Amazon)

Chi: The Year of Magical Thinking by Joan Didion (Wikipedia) and Innovations in Nephrology (Springer Nature)

Sam: Monopoly Super Electronic Banking Board Game (Amazon)

Joel: Song Sung Blue (Wikipedia)

The Filtrate

Joel Topf (kidneyboy.bsky.social)

AC (@medpeedskidneys.bsky.social)NephMadness

Anna Gaddy (@AnnaGaddy)

Vipin Verghese (@vipvargh.bsky.social)

Natalie Freidin Program director at Medical University of South Carolina

Special Guests

Anna Vinnikova (@kidneywars.bsky.social) Long time game maker for NephMadness and Associate Professor at Virginia Commonwealth University

Autumn Harris Associate Professor of Veterinary Medicine at NC State

Sarah Street MD PhD Assistant Professor of Medicine at Virginia Commonwealth University

Editing

Joel Topf

Show Notes

Animal House scouting report

Autumn Harris on Team Cat

Cheese!

I know 2026 feels like it ihas been here for months, but only a few weeks ago we were celebrating the nephrology accomplishments of 2025. The New Filtrate came together to review the year.

The Filtrate

Joel Topf‍ ‍@kidneyboy.bsky.social‬ (COI)

Swapnil Hiremath @hswapnil.medsky.social and on LinkedIn Editor in Chief of Kidney International Case Reports

Anna Gaddy (@AnnaGaddy) Winner of NephJC Rookie of the Year 2020

Nayan Arora (@CaptainChloride.bsky.social)

AC (@medpeedskidneys.bsky.social)

Vipin Verghese (@vipvargh.bsky.social) co-winner of NephJC Engaged Scientist of the Year in 2021

Brian Rifkin (@brianrifkin.bsky.social) Co-Editor in Chief NephJC. Winner of NephJC Rookie of the Year 2021

Cristina Popa (@NephroSeeker) Co-Editor in Chief NephJC. Wwinner of NephJC Rookie of the Year 2022 and MVP 2023

Editing and Show Notes by

Anna Gaddy and Joel Topf

The Kidney Connection written and performed by Tim Yau

Show Notes

Top Stories in Nephrology 2025 (NephJC)

First Top sories in Nephrology 2010! (Renal Fellow Network)

Links to all of the Top Stories in Nephrology, hosted on NephJC since 2017 (NephJC)

1. IgA Nephropathy

VISIONARY: Sibeprenlimab in IgA Nephropathy — Interim Analysis of a Phase 3 Trial (NEJM)

ORIGIN 3: A Phase 3 Trial of Atacicept in Patients with IgA Nephropathy (NEJM)

APPLAUSE-IgA Alternative Complement Pathway Inhibition with Iptacopan in IgA Nephropathy (NEJM)

Aliza M. Thompson, MD, MS (ASN)

2. Lupus Nephritis

REGENCY: Efficacy and Safety of Obinutuzumab in Active Lupus Nephritis (NEJM)

3. Nobel prize winner and peripheral immune tolerance

4. Xenotransplantation

5. GLP1ra Revolution

Remodel REMODELing mechanistic trials for kidney disease: a multimodal, tissue-centered approach to understand the renal mechanism of action of semaglutide (Kidney International)

SURPASS-CVOT Tirzepatide vs. Dulaglutide Is Associated with Reduced Major Kidney Events in Patients with Type 2 Diabetes, CVD, and Very High-Risk Kidney Diseases (Kidney Week abstract in JASN)

Poll: 1 in 8 Adults Say They Are Currently Taking a GLP-1 Drug for Weight Loss, Diabetes or Another Condition, Even as Half Say the Drugs Are Difficult to Afford (KFF survey)

6. GDMT implementation in CKD: lessons learnt from CONFIDENCE and MIRO-CKD

Confidence Finerenone with Empagliflozin in Chronic Kidney Disease and Type 2 Diabetes (NEJM)

MIRO-CKD Balcinrenone in combination with dapagliflozin compared with dapagliflozin alone in patients with chronic kidney disease and albuminuria: a randomised, active-controlled double-blind, phase 2b clinical trial (The Lancet)

7. Flozin Meta analysis

SMART-C. SGLT2 Inhibitors and Kidney Outcomes by Glomerular Filtration Rate and Albuminuria. A Meta-Analysis (JAMA)

SMART-C. Effects of Sodium Glucose Cotransporter 2 Inhibitors by Diabetes Status and Level of Albuminuria. A Meta-Analysis (JAMA)

8. Paradigm Shift: Aiming for CKD Remission

9. Fish Oil and Dialysis

PISCES Fish-Oil Supplementation and Cardiovascular Events in Patients Receiving Hemodialysis (NEJM)

10. Decline in Dialysis Patients in the United States

USRD 2025 Annual Data Report (USRDS)

Tubular Secretion

Swapnil Hiremath Alien Earth on FX Hulu (Wikipedia)

AC A Christmas Carol by Charles Dickens (Wikipedia) and The Muppet Christmas Carol (Wikipedia)

Anna Monty Don (Wikipedia)

Nayan Back Street Boys at The Sphere (Wikipedia)

Brian Marty Supreme (Wikipedia)

Cristina The Yellow Tie (Wikipedia)

Vipin Stranger Things, good for a four year old? (Wikipedia)

Joel Crash Course: The Universe with Katie Mack and John Green (Apple PodCasts)