Determination of the value of neutrophil gelatinase-related lipocalin and renal resistive index in the diagnosis and prognosis of sepsis-associated acute kidney injury

Objective: In our study, the values of NGAL, RRI, PI and PVI were examined in predicting the presence/development of AKI and mortality in patients followed up with sepsis in the ICU. Materials-methods: 158 patients hospitalized in the ICU with the diagnosis of sepsis were followed for five days in terms of the development of AKI according to the KDIGO criteria, and they were divided into two groups as those who developed AKI and those who did not. On the first and fifth days of sepsis diagnosis, blood samples were taken for NGAL levels, RRI was measured with Doppler USG, and PI and PVI values were recorded. Besides demographic data, 28-day mortality was also recorded. Results: The study was completed with 101 patients, and 66 (65,3%) of the patients developed AKI. Age, presence of additional disease and malignancy, APACHE II, SOFA score, vasopressor use and mortality rate were higher in patients who developed AKI (p<0,05). On the first day, NGAL, RRI and PVI levels were found to be significantly higher in patients with AKI, while PI was lower (p<0,05). On the fifth day, RRI and PVI were significantly higher in patients with AKI than those without (p<0,05). RRI and PVI levels were significantly higher on the first and fifth days, and PI levels were significantly lower in patients who were mortal than those who did not (p<0,05). It was observed that all four parameters measured on the first day were significant in predicting AKI, but RRI was superior to the others, and RRI and PVI values were significant on the fifth day (p<0,05). It was observed that RRI, PI and PVI values were significant in both periods, being more significant on the fifth day in demonstrating mortality (p<0,05). Conclusions: While RRI is an important predictor of AKI in the early stages of sepsis and mortality in the early and late stages, NGAL is a biomarker that can only be used to predict AKI. PI and PVI can be used to predict mortality as they are affected by fluid and perfusion status, but their role for AKI is questionable. Key words: acute kidney injury, neutrophil gelatinous associated lipocalin (NGAL), mortality, perfusion index, pleth variability index, renal resistive index, sepsis