In the NEWS: The New Kidney Health Order

Few weeks ago, there was an executive order signed to advance kidney health in the US. This is an historic event for the field of Nephrology and for kidney patients. The above image is a visual abstract that summarizes the changes that might be coming in 2020. This image is courtesy of Dr Tejas Desai @nephondemand

The goal of this order is to increase home dialysis options, increase organ transplantation and promote kidney health and keep patients "away from dialysis".  In addition, several incentives have been built in to allow for improved compensation for physicians and what looks like better options for patients. What does this mean for Nephrology?- Time will tell but this is a huge improvement in terms of patient care and patient choices. Hope this also sparks some more interest in the field of nephrology where we are still struggling for trainees.

Concept Map: Oral Agents to treat Hyperkalemia- a summary

This is a concept map of the 3 oral GI agents used to treat hyperkalemia.

Topic Discussion: Amyloidosis and Renal Infarction

Usually when we think of amyloidosis in the kidney- we think of paraprotein mediated amyloidosis (AL or AH) leading to nephrotic syndrome and in some rare cases- vascular amyloid presenting as AKI.

A recent study published in Mayo Clinic Proceedings suggests that renal infarction might be a common finding in patients with cardiac amyloidosis. Three groups of patients were identified according to the underlying amyloidosis disorder: AL amyloidosis in 24 patients, mutated-transthyretin amyloidosis in 24 patients, and wild-type transthyretin amyloidosis in 39 patients. Patients with AL amyloidosis had significantly higher N-terminal pro-B-type natriuretic peptide levels (P=.02) and were more likely to have nephrotic syndrome (P<.001). Renal infarction was detected in 18 patients (20.7%), at similar frequencies in the various groups. The likelihood of RI diagnosis was 47.1% (8 of 17) in the presence of AKI and 14.5% (10 of 69) in its absence (P=.003).  Renal infarction (defined by defect(s) on the DSMA scan) was reported in 20.7% of patients with and 25% without evidence of cardiac amyloidosis. Prior studies have not really shown any association like this before of amyloidosis and infarction. Renal infarcts were described in an autopsy study in 3 kidneys that had either cast nephropathy, plasma cell nodules, or autolysis but not with amyloid deposits. Dang et al interesting are reporting is a high percentage of abnormal DSMA scans in patients with wild-type transthyretin amyloidosis (wtATTR) and mutant transthyretin amyloidosis (mATTR) amyloidosis.

These findings are intriguing. The 20% to 25% prevalence reported by Dang and colleagues was therefore unexpected. Renal involvement in ATTR is thought to be rare, especially in patients with wtATTR amyloidosis. Recent drugs used to treat this form of amyloidosis might lead to a glomerulonephritis( my recent post). The finding from the current study suggests that we may be vastly underestimating the prevalence of kidney involvement in ATTR amyloidosis. These patients usually don’t present with nephrotic range proteinuria but more with AKI and subacute AKI. Perhaps, instead of labeling all of these as cardio-renal syndrome, we should consider looking for renal infarction in these patients. And as I have always thought about ruling out amyloidosis in young males who present with renal infarction, I usually stop at AL-AH amyloidosis testing. Given the above findings, perhaps an amyloid scan to look for wtATTR and mATTR might be important as perhaps renal infarction could be a potential relationship here. 

Quite an interesting association!!

Topic Discussion: Tumor Lysis Syndrome with immunotherapy

At this point the nephrology and oncology community is very aware of the AIN, glomerular diseases including vasculitis and ATN seen with check point inhibitors… but we might not be aware of tumor lysis syndrome that this drug can entice in certain patients. 

In the last 2 years, I found several published reports of TLS with check point inhibitors.

Here is a table I created to help with the theme on this one

Immunotherapy	Age	Gender	Cancer type	Time to TLS	Dialysis needed?	Outcome	Reference
Nivolumab	76	Male	Melanoma	5	Yes but declined	Disease progression-death	http://www.alliedacademies.org/articles/acute-tumor-lysis-syndrome-after-antipd1-immunotherapy-nivolumab-for-metastatic-melanoma-8038.html
Atezolizumab	77	Female	GU cancer	14	Yes	Disease progression-death	http://www.acanceresearch.com/cancer-research/tumor-lysis-syndrome-following-a-single-atezolizumab-infusion-for-metastatic-urothelial-carcinoma-involving-both-upper-and-lower-t.php?aid=18193
Atezolizumab	-	-	Solid tumor	-	-	-	https://www.ncbi.nlm.nih.gov/pubmed/25428504
Atezolizumab	-	-	Solid tumor	-	-	-	https://www.ncbi.nlm.nih.gov/pubmed/25428504
Ipilumumab	73	Male	Melanoma	6	No	Death	https://www.ncbi.nlm.nih.gov/pubmed/27256718
Nivolumab	74	Male	RCC	2	No	Death	https://medcraveonline.com/JCPCR/JCPCR-08-00271.php

Based on this, it is seen with PD-1, PDL1 and CTLA4 inhibitors and melanoma and urological cancers. A recent review in JON showed a case of a patient getting TLS with melanoma.  So it’s hard to tell if these agents are causing it or is it the burden of tumor- usually solid tumors in these cases.

Concept map: Hyponatremia in the cancer patient

This concept map was adapted and inspired by Umut Selamet and Ala Abudayyeh, both onconephrologists.

Consult Rounds: Causes of Osmotic Demyelination unrelated to hyponatremia correction

Osmotic Demyelination syndrome (ODS) is classically been associated with rapid correction of hyponatremia. But sometimes, in some rare cases, we observe other causes of this syndrome.
Here is a list that encompasses other known causes of ODS

Hyperglycemia
Hypernatremia( acute formation)
Hypoglycemia
Hypokalemia( this is well known entity causing it)
Alcoholism( This is probably the most important one)
Liver disease and liver transplantation
Malnutrition( another important one)
Hypophosphatemia
Use of CNI( not sure of the mechanism of this one)
Lithium use

This article from AJKD is an amazing reference.

Detective Nephron: Next Venture

Check out the next episode of Detective Nephron in ASN Kidney News

https://www.kidneynews.org/kidney-news/fellows-corner/detective-nephron/detective-nephron-june-2019