IATROGENIC PERIOPERATIVE HYPERVOLEMIA: A NOVEL UNRECOGNIZED ETIOLOGY OF DELAYED RENAL ALLOGRAFT FUNCTION - TWO CASE SERIES.

Introduction:

Forward heart failure and low cardiac output alone do not define the degree of renal dysfunction in cardiorenal syndrome. The term "congestive renal failure" was coined in 2012 by Ross to depict the role of renal venous hypertension in type 1 acute cardiorenal syndrome. This syndrome has also been termed congestive nephropathy (CN). Our understanding of congestive nephropathy continues to evolve: In 2024, we still do not know or fully understand the pathophysiology of CN. Furthermore, we do not have any known reports of CN, post-transplantation, in renal allografts. We present two cases of delayed graft function post-transplantation, and we hypothesize that iatrogenic perioperative hypervolemia and subsequent congestive renal allograft nephropathy represented a new unrecognized cause of delayed graft function.

Methods:

Two case series are herein described.

Results:

Case I

 A 48-yo female with ESRD from Fabry's disease received a deceased donor kidney transplant in late April 2024. There was evidence of hypervolemia and fluid retention with minimal urine output despite IV Furosemide + IV Chlorothiazide infusions.  Subsequently, urine output improved with combination IV diuretics. She later experienced an acute rejection episode that responded well to Corticosteroids and Thymoglobulin, 18 days post-transplantation. Latest creatinine, 4 months’ post-transplantation, was 1.50 mg/dL.

Case II 

A 63-yo female with ESRD from polycystic kidney disease received a deceased donor kidney in mid-August 2024. The patient continued to have slow graft function with minimal urine output and positive hypervolemia despite IV Furosemide 120 mg every 6 hours + IV Chlorothiazide 500 mg every 8 hours. With persistent hyperkalemia, unresolved hyponatremia with worsening hyperphosphatemia, she had urgent 3-hour hemodialysis treatment on post-operative day 2 with ultrafiltration. She did not need any additional hemodialysis treatment. Latest creatinine two weeks post-transplantation was 1.52 ng/dL.

Conclusions:

To our knowledge, these represent the first reports of renal allograft congestive nephropathy resulting from iatrogenic perioperative hypervolemia producing delayed graft function in new renal allografts. Our report calls for further study. 

The serum creatinine trajectory supports the speculation that both the newly transplanted renal allografts were simultaneously negatively impacted by congestive nephropathy. The response of falling creatinine down to 8.1 at last testing supports this hypothesis. Further investigation is warranted. We are putting together a series of similar presentations post-transplantation to make a very strong case for the existence of this newly previously unrecognized syndrome. We would advocate for a more nuanced and balanced approach to the perioperative use of intravenous fluid therapy post-transplantation.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.