Continuous renal replacement therapy in critically ill patients does not affect urinary neutrophil gelatinase-associated lipocalin levels

Failure 1 (5.5%) In the present study, we assessed urinary neutrophil gelatinase-associated lipocalin (uNGAL) during 24-hour continuous renal replacement therapy (CRRT) in critically ill patients. The study was performed in accordance with the Declaration of Helsinki and was approved by the Scientific Council and the Ethics Committee of Evangelismos Hospital in Athens, Greece. Informed consent was provided by family members of the patients included in the study. Eighteen critically ill patients (13 men and five women with a mean age of 69 ± 14 years) in an interdisciplinary intensive care unit underwent continuous veno-venous hemodiafiltration (CVVHD). Three had oliguria (urine output of less than 200 mL per 12 hours). Patient characteristics at enrollment are shown in Table 1. uNGAL was determined before CRRT onset and at 6 and 24 hours during CVVHD. uNGAL was measured by using a chemiluminescent assay with ARCHITECT technology (Abbott Diagnostics Inc., Abbott Park, IL, USA). For CVVHD, pump-driven machines from Prisma (a brand of Gambro, Deerfield, IL, USA), Kimal (Dormagen, Germany), or Nephro-Tech (Shawnee, KS, USA) were used with a 0.9 m polysulfone filter. uNGAL levels did not change, whereas serum creatinine and serum cystatin C significantly decreased (Table 2). No correlation was found between uNGAL levels and the illness severity scores at inclusion. In a study by Schilder and colleagues [1] in a previous issue of Critical Care, plasma NGAL (pNGAL) in critically ill patients was similarly not affected by RRT. No net removal of pNGAL was established, although absorption by the filter with concomitant production could not be