Correspondence questions fluid balance and glucose exposure with Carry Life UF

Correspondence in the Journal of the American Society of Nephrology raises questions about a prospective, multicenter, randomized crossover study of the Carry Life UF system for steady glucose concentration peritoneal dialysis. The study assessed home treatment over four weeks and reported higher ultrafiltration volume, sodium removal, and glucose ultrafiltration efficiency than a 2.5% dextrose control exchange. The correspondence does not provide the sample size or numerical treatment effects.

The correspondents note that ultrafiltration was calculated from two home treatments per week, without reporting total weekly peritoneal ultrafiltration. They question whether substituting 1.5% for 2.5% dextrose on four days weekly could cause negative ultrafiltration in fast peritoneal transporters, potentially undermining maintenance of euvolemia. This is a concern raised by the authors, not a demonstrated outcome.

They also challenge the interpretation of reduced peritoneal glucose exposure. Although the control exchange produced a glucose peak lasting approximately 30 minutes, Carry Life UF maintained elevated dialysate glucose concentrations for longer. Their estimates from a published figure suggest a higher glucose concentration–time area under the curve with the device. The correspondence presents no new trial data and supports longitudinal studies to establish sustained fluid balance and assess potential effects on the peritoneal membrane.