Haemodialysis alters peripheral nerve morphology in end-stage kidney disease.

Abstract

We explored the nerve ultrasound (US) characteristics of 15 patients with end-stage kidney disease (ESKD) and correlated these findings with clinical severity and electrophysiological parameters of neuropathy. 15 ESKD patients on thrice-weekly high-flux haemodialysis and 15 healthy controls were enrolled. Sonographic and electrophysiologic studies were conducted before and after a single session of haemodialysis. Serial measurements of median nerve cross-sectional area (CSA) and hypoechoic fraction (HF) were performed at the same non-entrapment site in the mid-forearm. Neuropathy severity was quantified using the total neuropathy score (TNS). 86.7% of the ESKD cohort had neuropathy (TNS>1). ESKD patients had significantly higher baseline CSA (8.9±1.2mm2 vs 7.5±1.0mm2, p<0.05) and HF (56.0±1.0% vs 54.0±1.1%, p<0.05) compared with the control group. The CSA correlated significantly with TNS (r=0.826; p<0.0001) and other electrophysiological parameters. There was a reduction in both the CSA (8.3±1.4mm2; p<0.01) and HF (55.0±1.6%; p<0.05) after a single session of HD. A significant relationship was also found between the change in CSA and change in serum K+ after dialysis (r=0.782, p<0.01). This study shows that peripheral nerves in ESKD patients are larger and more hypoechoic and that these morphological abnormalities may be reversed by dialysis. US may be useful as an early marker of neuropathy in ESKD.