RRT in TLS

Q: Which of the following Renal Replacement Therapy (RRT) is preferred in Tumor Lysis Syndrome (TLS)? (select one)

A) Continuous venovenous hemodialysis (CVVHD) 

B) Intermittent hemodialysis (iHD) 

Answer: A

CVVHD is considered better in TLS as iHD may cause rebound hyperphosphatemia after the session is over. Moreover, the threshold of initiating RRT in TLS is low. Early RRT in TLS has been shown to be beneficial. This is particularly true when rasburicase is not available or has not been used. 

Early RRT in TLS saves lives as there is a tendency for potentially rapid potassium release and accumulation. Also, complete recovery of renal function is usual when early RRT is applied which rapidly lowers uric acid and phosphate concentrations. Acute uric acid nephropathy leads to oliguria and results in complete renal failure, which can be prevented by early RRT. The response to early RRT is very robust in decreasing uric acid. In contrast, hyperphosphatemia is relatively more resistant to RRT, though still it gives excellent results.

Besides other known indications of RRT in ICU, some of the major indications of RRT in TLS are:

1. persistent hyperkalemia

2. hyperphosphatemia-induced symptomatic hypocalcemia

3. calcium-phosphate product ≥70 mg2/dL2

Complete recovery of renal function is usual when early RRT is applied which rapidly lowers uric acid and phosphate concentrations. 

#nephrology

#electrolytes

#oncology

References:

1. Tan HK, Bellomo R, M'Pis DA, Ronco C. Phosphatemic control during acute renal failure: intermittent hemodialysis versus continuous hemodiafiltration. Int J Artif Organs 2001; 24:186.

2. Cairo MS, Bishop M. Tumour lysis syndrome: new therapeutic strategies and classification. Br J Haematol 2004; 127:3.

3. Pichette V, Leblanc M, Bonnardeaux A, et al. High dialysate flow rate continuous arteriovenous hemodialysis: a new approach for the treatment of acute renal failure and tumor lysis syndrome. Am J Kidney Dis 1994; 23:591.