Validation of peritoneal neutrophil gelatinase-associated lipocalin as a biomarker for peritonitis: A comparison between laboratory-base method and rapid stick test

Abstract

Neutrophil gelatinase-associated lipocalin (NGAL) is a multifunctional protein with roles beyond biomarker status, influencing critical processes. This study aimed to assess dipstick test for NGAL (NGALds), a novel dipstick test, against the established laboratory-based NGAL (NGALlab) method for early peritonitis detection, focusing on peritoneal fluid analysis to provide a rapid and cost-effective diagnostic tool for peritonitis management. Conducted at San Bortolo Hospital, Italy, this retrospective study collected samples from suspected or confirmed peritonitis cases between May 1, 2021, and December 31, 2021. Samples included peritoneal dialysate effluents (PDE) and underwent white blood cell counts, NGALds, NGALlab, and effluent culture. The study analyzed 27 peritonitis cases, involving 133 PDE samples from 22 patients. NGALds exhibited a strong correlation (Rs = 0.732, P < 0.05) with NGALlab, particularly for medium to high-risk peritonitis cases, with a 98% accuracy rate. NGALds effectively aligns with NGALlab for peritonitis diagnosis, offering a valuable diagnostic tool, particularly suitable for point-of-care and resource-limited healthcare settings. Further research should investigate its correlation with neutrophil levels in PDE, solidifying NGALds as an accessible and efficient resource for peritonitis management.