Topic Discussion: Pseudo AKI with anti cancer agents

Legend: AKI, acute kidney injury, MATE, multidrug and toxic compound extrusion; OAT, organic anion transporter; OCT, organic cation transporter

As of April 2024--most updated data on anti-cancer agents and Pseudo-AKI.

Several classes of cancer treatments are associated with pseudo-AKI.  Providers must be aware of this phenomenon, as pseudo-AKI can lead to temporary stopping and even permanent discontinuation of life-saving treatments. When patients present with increases in serum creatinine while on these drugs, checking a serum cystatin C level may help differentiate true AKI from pseudo-AKI.

Shruti Gupta and Kenar Jhaveri 

In the NEWS: Intravitreal Anti VEGF agents and Kidney disease

 Check out this twitter feed I had done on the topic of Intravitreal Anti VEGF agents and the Kidney. 

Nephro- hospitalists?- should we consider this

Not much has been written regarding the role of a nephro-hospitalists in the Nephrology literature. There is one perspective back in 2019, before the pandemic that discusses the evolution of nephrology as a medical specialty and addresses the challenges it faces, particularly the declining interest among medical trainees in pursuing careers in nephrology. The authors emphasize the importance of adapting to these challenges and propose a solution in the form of a nephrology hospitalist model.

The field of nephrology has evolved significantly from its early focus on kidney physiology to becoming an independent clinical specialty, particularly with the introduction of dialysis in the 1960s. While patient care was initially delivered primarily in hospitals, the growing population of individuals with kidney disease led to a shift in care to outpatient settings, with a recent emphasis on subspecialized training in transplantation, interventional, and critical care nephrology.

The decline in interest among medical trainees in nephrology careers is attributed to various factors, including a lack of mentorship, the complexity of kidney physiology, busy workloads, perceived lower compensation, and a perceived lack of innovation in therapies and dialysis.

To address these challenges, the authors introduce the concept of a nephro-hospitalist model, exemplified by the experience at Washington University in St. Louis. The model involves a dedicated nephrology hospitalist service comprising attending physicians focusing on inpatient care and medical education. Medical students and rotating internal medicine residents are preferentially placed on this service, and the model includes a flexible schedule of alternating periods of service.

The benefits of this model include improved teaching and mentorship for trainees, increased elective time for fellows, and the opportunity for attending physicians to foster specific interests. The authors highlight the positive impact on education and mentorship, which is crucial for attracting trainees to nephrology.

However, the authors also acknowledge the downsides to the model, including the need for an every-other-month schedule to prevent burnout and potential limitations in attracting new trainees. Financially, the model is described as roughly break-even, and the authors note that financial considerations should be weighed against the educational benefits.

The paper discusses other institutions that have adopted similar models with varying success and mentions the potential role of nephrology hospitalists in private practices, particularly to mitigate issues related to "windshield time" and electronic health record systems.

What have other fields done

Check out this regarding the role of onco-hospitalists and cancer hospitals.
Other fields such as GI and Neurology as well have adopted this model. 

It is possible that a full-time hospital-based nephrology model can be a valuable addition to nephrology education, providing increased attending contact and mentorship for residents and medical students. We should consider further exploration of innovative models to expose trainees to the unique aspects and satisfactions of nephrology, ultimately aiming to address workforce challenges and recruit future nephrologists.

CMML and the Kidney

 

This figure summarizes the various glomerular, reno-vascular and tubulointerstital disorders seen with Chronic Myelomonocytic leukelmia ( recent review in Kidney Medicine by us)

Concept Map: AKI in ECMO

 

Concept Map of pathophysiology related to AKI in a patient on ECMO- created by Dr. Purva Sharma using biorender.com 

Concept Map- Immune checkpoint inhibitors and AKI- biomarkers

 

As of 2023, this is the most updated bio-markers that have been studied at single centers around the world for AKI associated with ICI therapy. 

References:

Tertiary lymphoid structure signatures are associated with immune checkpoint inhibitor related acute interstitial nephritis

Soluble and cell-based markers of immune checkpoint inhibitor-associated nephritis

AKI in patients with immune check point inhibitors

Biomarkers, Clinical Features and rechallenge for ICI related renal immune related adverse events

Cytokines and immune cell phenotypes in AKI associated with ICI

Differentiating acute interstitial nephritis from ICI from other causes

Concept Map: Kidney Involvement in Erdheim Chester Histiocytosis

This concept map in inspired by work in this paper by Chazal et al in Kidney International

 

Concept Map: Acute Pancreatitis and AKI

 

Special post by 

Lakshmi Kannan, MBBS, MD, 

Department of Nephrology, Pikeville Medical Center

Adjunct Faculty, University of Pikeville Kentucky College of Osteopathic Medicine

Kentucky, USA

Reference is here

Concept Map: AKI in patients with Chronic Liver Disease

 

Concept map of AKI associated with chronic liver disease. Made using biorender.com 
Inspired by an article in CJASN

In the News: Vonoprazan and the Kidney

A new agent has been found to cause AKI and AIN—Vonoprazan.  A recent paper in Kidney International is the first to describe this from Japan. The authors used the National reporting database of drug toxicities in Japan to assess this and compared it to PPIs—JADER database.  See visual ab from the recent paper. 

What is vonoprazan? 

Vonoprazan, a potassium-competitive acid blocker possessing a new mechanism of action. Vonoprazan inhibits acid secretion in the cells of the gastric wall. The inhibitory effect of vonoprazan on H+, K+-ATPase is perhaps over 300 times greater than that of lansoprazole. 

In Japan, this drug was approved for use for acid reflux in 2015. In the US, this drug has been FDA approved for esophageal esophagitis in association with H pylori recently in May 2022.  A recent meta-analysis also found that vonoprazan is non inferior to PPIs as therapy for GERD but in the subgroup for severe erosive esophagitis- it was more effective.

In this recent study in KI, authors compared PPI related renal adverse events to this new agent. The total numbers of renal adverse events associated with PPIs and vonoprazan were 14149 and 2465, respectively. Surprisingly, a safety signal for vonoprazan and a drug associated AIN —was detected, which was similar to that obtained for PPI. Interestingly. a safety signal for AKI caused by PPIs and vonoprazan were not detected.

The mechanism of action of vonoprazan is that it competes with potassium ions for the reversible inhibition of H+- K+-ATPase, whereas PPIs act by binding covalently to the gastric H+, K+-ATPase via disulfide bonds.  Having a H+, K+-ATPASe in the kidney have any impact? Not sure?

Another interesting finding from another study showed increase tacrolimus levels when this agent is used- a caution in our GN and transplant patients.

As we learn more about this agent in the US, we need to be vigilant!

Topic Discussion: CDK4/6 inhibitors and the Kidney

Selective estrogen receptor inhibitors and aromatase inhibitors are the mainstay of therapy for hormonal receptor-positive (HR+) breast cancer; however, most metastatic HR+, human epidermal growth factor receptor 2-negative (HER2-) progress and acquire resistance to endocrine therapies. Cyclin-dependent kinase 4/6 inhibitors (CDK4/6 inhibitors) comprise a new class of drugs that overcome this resistance.  Three CDK4/6 inhibitors—palbociclib, ribociclib, and abemaciclib—have been approved for HER2-negative metastatic breast cancers, usually in combination with hormone therapy. 

Interestingly, the renal community has seen elevated serum creatinine associated with these agents. Several early trials of palbociclib and ribociclib did not describe the incidence of AKI, whereas clinical trials of abemaciclib have reported that up to 25% of patients experienced a rise in creatinine. In vitro studies of abemaciclib have shown that the drug and its major metabolites inhibit renal transporters like organic cation transporter-2, multidrug and toxin extrusion-1 (MATE-1), and MATE2-K, potentially leading to a reversible rise in creatinine without actually changing GFR. Cases have been described that show this pseudo-AKI. 

More recently, biopsy proven cases of acute tubular injury also have been noted- 6 cases with tubular and interstitial damage.

Finally, a search of the FAERs database revealed that, in addition to AKI, metabolic disturbances like hypokalemia, hyponatremia, and hypocalcemia may occur while on CDK4/6 inhibitors. Hyponatremia has been reported with ribociclib and with abemaciclib and grade 2 hypokalemia was reported in 20.8% of patients taking abemaciclib. 

In summary, the common renal associations with CDK4/6 inhibitors are

Pseudo AKI, ATI, hyponatremia, hypokalemia and hypocalcemia

Detective Nephron: Next Venture Oct 2021

 Here is the next DN case of AKI

http://onlinedigeditions.com/publication/?m=15191&i=724592&p=36&ver=html5

In the NEWS: Immunotherapy and the Kidney( new data in 2021)- AKI and electrolytes

Immune checkpoint inhibitors (ICI) are a novel class of immunotherapy drugs that have vastly improved cancer care for patients. Data on AKI has been evolving. 

In a multicenter international study just published in JITC by Gupta et al involving 30 sites across 10 countries, researchers collected data on 429 patients with ICI-AKI and 429 control patients who did not develop ICI-AKI. Armed with the largest ICI-AKI database to date, the team of researchers was able to identify predictors, recovery potential and survival outcomes of those patients with ICI-AKI.

One of the most important findings from the two-year study reveals that among patients who take ICI again – even after an episode of ICI-AKI – only 16.5 percent developed recurrent ICI-AKI, which shows that most patients can still take these life-saving medications safely.

Additional findings show that in renal-recovery occurs in approximately two-thirds of patients with ICI-AKI. Early treatment with corticosteroid is associated with a higher likelihood of renal recovery. Lower baseline kidney function, proton pump inhibitor use and extrarenal immune-related adverse events are independent risk factors for developing ICI-AKI.

A related paper recently published in the journal Kidney International by Wanchoo et al looking at the scope of electrolyte disorders that are seen with ICI. Hyponatremia, hypokalemia and hypercalcemia were the most common findings. SIADH is the most common cause of hyponatremia and adrenal disorders led the way in the cause of hypercalcemia. 

Concept Map: Methotrexate Renal Toxicity

 

Picture created using biorender.com
Pathology pic obtained from google: Arkana lab collection. 

Concept Map: Anorexia Nervosa and the Kidney

 

IN the News: Pediatric AKI related with COVID19 and MISC- tale of two NY centers

 

A recent study published in Kidney International looked at a single health system 4 hospital admissions of AKI with COVID19 and MISC in children in NY. It was during the first wave in 2020.  

Over 150 patients met inclusion criteria; 97 (63.8%) with acute-COVID-19 and 55 (36.2%) with MIS-C, AKI occurred in 11.8% of the cohort; 8 with acute-COVID-19 and 10 with MIS-C.  All but one patient with AKI were admitted to a pediatric intensive care unit (PICU). There was no significant difference in age, or ethnicity in those with and without AKI. Those who identified as black had 2.86 times higher odds of AKI (p=0.042; 95%CI 1.04-7.93). 

Majority of AKI occurred early in the course of hospitalization, 72% (N=13) within 24 hours of admission. MIS-C patients with AKI had greater rates of systolic dysfunction, compared to those without AKI (80% vs 49%, p= 0.038).  AKI, in unadjusted models, was associated with a lower serum albumin level (OR 0.17)and higher white blood cell counts (OR 1.11). In addition, patients with AKI had 8.4 day greater length of stay. Major Limitations: 1. Small sample size precluded adjustment for confounders 2. As this was an observational study, we are unable to determine causal associations. 3. Single health system/region of the country
Strengths of this study: One of the largest, detailed cohorts of pediatric patients at the epicenter of the COVID-19 outbreak and represents a diverse racial, ethnic and socioeconomic population.

Similar to reports in other PICU patients, pediatric COVID-19-related AKI was associated with longer lengths of stay published in Kidney360 also from NY area. In that study, 57 children who met inclusion criteria, 46% (26/57) were found to have AKI.  All patients had resolution of AKI at discharge, with 61% achieving recovery by day 2. One patient required dialysis. When compared to those without renal injury, the AKI cohort was older (p < 0.001) and with higher median peak values of CRP (p <0.001), IL-6 (p <0.05), ferritin (p < 0.001), and procalcitonin (p <0.05). More patients with AKI had left ventricular systolic dysfunction (p < 0.001) and lymphopenia (p <0.01), when compared to those without AKI. No differences in Body Mass Index or sex were found. 

These findings may reflect the inflammatory cascade’s complex role in development and perpetuation of COVID-19 related AKI. In addition, decreased intravascular volume and distributive/cardiogenic shock may have contributed to AKI in the MIS-C cohort. 

Check out the tweetorial by Abby Baselely 

Topic Discussion: Acute Peritoneal Dialysis during COVID-19

 As the NYC area had seen surge of cases in all health systems in March, April, May 2020, need for creative solutions to do dialysis was essential. NYU and Weill Cornell in NYC were two centers that really pioneered this method during the COVID-19 pandemic. 

This manuscript published in Kidney360 highlights 39 acute catheter placements and use of PD in the acute setting. Almost 40% even had recovery of AKI. 

Here is the Cornell data of 11 patients published in KI reports, 6 patients recovered.

Two concerns that most would have is:

1. Entering the rooms to do cycler and exchanges.
2. Can PD be done in prone ventilation as proning helped COVID19 patients recover?

See this picture from the NYU series

The figure shows placement of the cycler outside the ICU room and using longer connectors. Drain bags were used to obliviate use of drain line. The room was also HEFA filtered for airborne isolation.

Another series of patients in NYU was published in PD International on how they were able to do successful PD in vented patients with proning. Although the mortality was 100%, the venting was not effected and relative clearance was good. 

Perhaps, the silver lining of COVID19 related AKI-- return of Acute PD...

Topic Discussion: Outcomes of AKI in COVID-19

 As COVID19 surged the NY area, March-May 2020 is when the AKI surge happened at most northeast hospitals. Initial reports from us and others showed that the incidence of AKI was high- close to 40%. 

At that time, almost 39% of patients were still admitted. Now there are 99% discharged allowing for complete outcome analysis. Here is our data on the outcomes of AKI in AJKD when all have been discharged. 

The aim of this study was to investigate in-hospital death and kidney outcomes among hospitalized patients with COVID-19 and AKI.  We reviewed health records of 9657 patients hospitalized with #COVID-19 between March1- April 27^th, 2020, and followed up to the day of discharge/death. The data was from 13 hospitals. To investigate the impact of AKI on in-hospital death, we performed cox regression using AKI as a time-varying exposure and in-hospital death as the outcome.

In the cohort 40% of patients developed AKI (incidence rate of 38.3 per 1000 patient-days). Those who developed AKI had higher proportion with DM, heart disease, chronic kidney disease and had a more severe illness. The death rate was much higher in the AKI requiring dialysis( 6.4 times more) compared to AKI not requiring dialysis (3.4 times more) compared to no AKI. 

What matters to us is what happens to patients who survived? - how many had CKD, how many were sent on dialysis?  The big finding-- Among patients with AKI non-dialysis requiring who had survived, 74% had kidney recovery at the time of discharge. For patients with AKI-on dialysis and survived, 67% had kidney recovery at discharge. For the remainder who did not have kidney recovery, 91.7% remained on dialysis at the time of discharge.  Among those with AKI-on dialysis who survived, the presence of chronic kidney disease was the only independent risk factor associated with need for dialysis at discharge. 60 and 90 day outcomes are lacking and will be eventually useful. 

Regardless of need for dialysis or kidney recovery at discharge, hospitalized COVID-19 patients who experienced any form of AKI should be followed closely post-discharge to assess ongoing kidney function.  Our 13 hospital sites were all in metropolitan NY during the early part of the pandemic; is the major limitation.  

So in patients hospitalized with #COVID-19, those with AKI was associated with higher risk of death, particularly among those who needed dialysis. Most surviving patients with AKI had kidney recovery upon discharge.

Another recent study from a NY metro area showed similar findings in JASN.  Of 3993 hospitalized patients with COVID-19, AKI occurred in 1835 (46%) patients; 347 (19%) of the patients with AKI required dialysis. Of survivors with AKI who were discharged, 35% had not recovered to baseline kidney function by the time of discharge. An additional 36% patients who had not recovered kidney function at discharge did so on posthospital follow-up.

Finally, a research letter in CJASN showed some outcomes data from yet another NY center. Patients with AKI had higher mortality than patients without AKI (40% versus 8%).  Among the patients with AKI, 48% recovered to their baseline kidney function. Among the 52% who did not recover to their baseline kidney function, 43 received dialysis, among which 34 were dialysis dependent and 26 died (60%), and 111 did not receive dialysis, among which 80 (72%) died.  

Topic Discussion: COVID and Kidneys- the biopsy experience

As we expand our understanding of COVID-19 related AKI, in the last few weeks, more studies are emerging on what might be the main kidney biopsy findings with COVID related AKI.
We have now established the incidence being around 30-40% in the US.

What is exactly going on in the kidney? Is the virus attacking the kidney or is the renal disease a consequence of "being sick" and or  "inflammatory state".

This figure from an article in JASN summarizes the potential way the SARS-Cov2 might be effecting the kidney



Two recent biopsy series from Columbia and Northwell Nephrology showed the variety of pathology reported in COVID-19



In addition, an autopsy series (specific) to the kidneys showed ATN only.  Finally, in KI, a series of anti GBM were reported in UK related to COVID-19

All recent papers added interesting few things to the ongoing literature.

1. ATN is by far the most common presentation for AKI( if not pre renal)- even in transplanted kidney. Pigment nephropathy from myoglobin or hemoglobin is rare. Vitamin C overdose induced oxalate nephropathy is rare.
2. Podocytopathies( MCD and cGN) are the most common glomerular findings
3. Other glomerular diseases are a varied amount( TMA, ANCA, Membranous GN, anti GBM)
4. The virus was not found in the kidney with immunohistochemistry in all 3 studies.

Does the kidney get infected?- time will tell.. data is mixed

In the News: AKI in COVID-19 patients, a study and a story ( pics and words)

(Our fearless fellows during COVID-19)

As we tackle the world of COVID-19, at Northwell, we faced a lot of AKI related to COVID-19.
We were able to gather this data and publish a large 13 hospital dataset from US looking at AKI related to COVID-19. The data was just released in Kidney International today. This study is dedicated to all the patients and families we helped treat and our fearless warriors in this fight- our faculty, fellows, nurses, and all nephrology division staff at the two main campuses of North Shore University Hospital and LIJ at Northwell. Without their hard work, this study wouldn't be possible. We wanted to share some of our data here ( as a summary) with some personal faculty/fellows pics from the last 2 months of hard work.

1. When NY became the epicenter of COVID-19, nephrologist across NY noticed an alarming number of patients who developed AKI, at rates higher than reported in China. Our study reports the AKI rate and describes the presentation and risk factors of AKI in this population. We reviewed health records of patients hospitalized with COVID-19 between March1- April 5th, 2020, and followed up through April 12th. The data was from 13 hospitals. Our final cohort had 5449 patients.

2. Out of 5449 patients, 1993 (37%) developed AKI (stage 1-47%, stage 2- 22% and stage 3- 31%).
Up to 14% of all AKI patients required renal replacement therapy. At the time of this writing, among patients with AKI, 694 died (35%), 519 (26%) were discharged and 780 (39%) were still hospitalized.

3. AKI occurred early in the course of hospitalization, with 37% either arriving with AKI or developing within 24 hours of admission.

4. AKI was primarily seen in Covid-19 patients with respiratory failure, with 89.7% of patients on mechanical ventilation developing AKI compared to 21.7% of non-ventilated patients.
276/285 (96.8%) of patients requiring RRT were on ventilators.

                                           (Our LIJ renal team with Dept of Medicine Chair)


5. We found that independent risk factors for AKI included older age, diabetes mellitus, cardiovascular disease, Black race, hypertension, vasopressor medications and need for ventilation. In our study, baseline ACE-inhib use and BMI were not risk factors for AKI.

6. Around 66% of the patients had a urine Na of <35, suggestive of a prerenal state. In urinalysis, 46% had +ve blood and 42% had +ve protein. Unfortunately, we do not have accurate data on urethral catheters and baseline proteinuria.

                                            ( Our North Shore Inpatient rounding teams)

7.Why was our AKI rate higher (37%) than the study reported (5%) by Cheng et al?
We cannot completely explain this difference, but their patients had lower rates of comorbidities and ventilation needs than our patients. Our rates seem consistent with reports from US hospitals that are going to be published soon. In a recent preprint from Mt Sinai in NY- AKI rate was also 40%. Another US study also published at the same time from New Orleans found a rate of 28%.

8. We found a close temporal relationship between AKI and timing of intubation. It is possible that these patients developed ATN during systemic collapse. Since the 66% of AKI patients had urine Na of <35, they could have prerenal AKI.

9. Although not a primary purpose of this study, among the 285 on dialysis, 55% died, 42% still in the hospital and 3% were discharged.

                                            (Our North Shore Inpatient rounding teams)

10. It is important to note that because of early censoring and incomplete hospital disposition data, we cannot make definitive inferences about outcomes. We will do an update on full outcomes in 30 days. This study to define the rate of AKI, timing and risk factors.

11 The goal of this study was a broad description of AKI in COVID-19 patients. We believe that it is very important this information becomes available rapidly for clinicians. A full assessment of all patients’ outcomes will require a longer period of time to allow for disease processes to fully play out.

                                               (Our chief and associate chief in action)

12 What limitations do we have? 1. The cause of AKI were not fully elucidated. 2. Since this is an observational study, we will not be able to make causal inferences between exposures and AKI. 3. CKD could not be assessed given EHR data mining.

13 What are the strengths of the study? This is the largest cohort to date of hospitalized patients with COVID-19 with a focus on AKI. Our identification of AKI is consistent with guidelines, well-validated and automatically calculated in real-time for almost 1 year.

Cause of AKI- likely ischemic ATN( but AKI can come in various variants as noted on my prior post but a recent NEJM article also highlights potential involvement of ACE2 and renal tropism in AKI seen with COVID-19. In addition, there is an excellent CPC this week in NEJM on AKI with COVID-19.

Check out the above updates and tweetorial by first author Jia Ng, MD

I want to share our new paper “Acute kidney injury in patients hospitalized with COVID-19”. @kidney_int @hofstrakidney @hofstramed @jam_hirsch @danielwross4 @purvasharma821 @hiteshhshah Richard Barnett @gracezra1 @sfishbane @kdjhaveri https://t.co/XzvPa1vKtk

[THREAD] pic.twitter.com/Rq24N6XrLR

— Jia Hwei Ng, MD, MSCE (@jiahweing) May 14, 2020

The real heroes of our renal fight against COVID-19- our dialysis nurses and technicians!