Background Protein energy wasting (PEW) is common in patients undergoing maintenance hemodialysis (MHD) and closely associated with poor outcomes. Insulin resistance and associated alterations in amino acid metabolism are potential pathways leading to PEW. We hypothesized that the measurement of leucine disposal during a hyperinsulinemic- euglycemic-euaminoacidemic clamp (HEAC) procedure would accurately measure the sensitivity to insulin for its actions on concomitant carbohydrate and protein metabolism in MHD patients. Methods We examined 35 MHD patients and 17 control subjects with normal kidney function by hyperinsulinemic-euglycemic clamp (HEGC) followed by HEAC clamp procedure to obtain leucine disposal rate (LDR) along with isotope tracer methodology to assess whole body protein turnover. Results The glucose disposal rate (GDR) by HEGC was 5.1 ± 2.1 mg/kg/min for the MHD patients compared to 6.3 ± 3.9 mg/kg/min for the controls (p = 0.38). The LDR during HEAC was 0.09 ± 0.03 mg/kg/min for the MHD patients compared to 0.11 ± 0.05 mg/kg/min for the controls (p = 0.009). The LDR level was correlated with whole body protein synthesis (r = 0.25; p = 0.08), with whole body protein breakdown (r = −0.38 p = 0.01) and net protein balance (r = 0.85; p < 0.001) in the overall study population. Correlations remained significant in subgroup analysis. The GDR derived by HEGC and LDR correlated well in the controls (r = 0.79, p < 0.001), but less so in the MHD patients (r = 0.58, p < 0.001). Conclusions Leucine disposal rate reliably measures amino acid utilization in MHD patients and controls in response to high dose insulin.

"If you can look into the seeds of time, and say which grain will grow and which will not, speak then unto me." -William Shakespeare. Macbeth. Act 1 scene 3.Because of reliable technology over several decades of experience and apparent cost effectiveness and safety, many in the dialysis industry would have assumed that dialyzer reuse would be a continuing fixture. But dialyzer reuse has become less common in favor of a single-use. In 1997, 82% of dialysis facilities practiced dialyzer reuse for some or all of their patients, but by 2005 this figure had declined to 39% (1, 2). Is there is a continuing role for dialyzer reuse in ESRD programs in the US? To address this, we briefly review the outcomes seen historically and presently between the practices of reuse vs. single-use, and then we discuss the factors that likely contributed to the decline of reuse across the US over the last decade and their implications in making a decision to reuse or not.