The impact of nephrectomy on liver and contralateral kidney volume in patients with ADPKD; a case series.

Abstract

Purpose: A substantial number of patients with autosomal dominant polycystic kidney disease (ADPKD) undergo nephrectomy. A decrease in intra-abdominal pressure after nephrectomy might hypothetically accelerate the growth of other polycystic organs and accelerate the rate of eGFR decline of the remaining kidney. In this case-series, we investigated the change in kidney and liver volume in patients before and after nephrectomy, and in a control group without nephrectomy.

Methods: In this retrospective case series kidney and liver volumes were measured using an automated stereological approach (MRI) or manual tracing (CT). Additionally, change in eGFR was investigated in patients before and after nephrectomy in whom this procedure did not result in an immediate need to start kidney replacement therapy (KRT).

Results: Twelve patients were included in the nephrectomy-KRT group and ten in the KRT-only control group. Kidney volume growth rates before start of KRT were similar between both groups (nephrectomy-KRT: 6.3 [95% CI: 4.0 to 8.4]; KRT-only: 6.7 [3.5 to 9.7] %/year, difference p = 0.8). After start of KRT, kidney volume significantly decreased in both groups (nephrectomy-KRT: -3.7 [-6.3 to -0.7]; KRT-only: -5.2 [-8.9 to -1.3] %/year, difference p = 0.5). The change in liver volume was not statistically different between both groups. In four additional patients in whom nephrectomy did not immediately lead to the start of KRT, the rate of eGFR decline of the remaining kidney did not change after the procedure.

Conclusion: In patients who did and did not undergo nephrectomy at the time they reached the need for KRT, kidney volume seemed to decrease after the procedure. In the two patients who had a nephrectomy of a functional kidney without direct start of KRT, nephrectomy did not seem to lead to accelerated eGFR decline of the remaining kidney. Due to the small sample size of this case series, these results have to be validated preferably in a large prospective multicenter study.