URINARY INTERLEUKIN-18 AS A BIOMARKER FOR EARLY DIAGNOSIS OF ACUTE KIDNEY INJURY IN INTENSIVE CARE UNIT IN ZAGAZIG UNIVERSITY HOSPITALS

BACKGROUND:Acute Kidney Injury (AKI) can occur spontaneously or iatrogenically, and rates of AKI continue to rise over the last two decades despite improvements in clinical care and development of preventive strategies. Diagnosis of AKI by serum creatinine is likely too late to prevent some of the early structural changes that characterize renal injury. Thus, there is a need for rapidly available, sensitive and specific biomarkers for AKI that would allow early prediction at a time when intensive care optimization can be performed. Currently, the detection of a reliable biomarker for early diagnosis of AKI would assist in facilitating early intervention, evaluating the effectiveness of the therapeutic intervention, and guiding pharmaceutical development. Urinary IL-18 was increased in mice with ischemic AKI compared to sham-operated mice. Thus we developed the hypothesis that IL-18 could be released from the injured tubular epithelial cells into the urine and serve as a urinary biomarker of AKI in humans. OBJECTIVE: The aim of this study is to Estimate U IL-18 in critically ill patients who will be admitted in I.C.U, to Assess validity of U IL-18 in early prediction of AKI and Compare the U IL-18 with s.creatinine (at admission, 6h and 24h after admission). METHODS: A total number of 84 patients that were critically ill who were admitted to medical ICU of Zagazig University Hospitals within 6 months and were classified into 2 groups :1) AKI group : The s.creatinine level was elevated either by 25% or more of the basal level or by ?0.3mg/dl above the basal level after 24 hours and It included 36 patients (22 males and 14 females) with age ranged from 29 years to 60 years with a mean values + SD of 47.7±8.8years. 2) Non AKI group : Rise of the s.creatinine level less than 0.3mg/dl above the basal level after 24 h. It included 48 patients (31 males and 17 females) with age ranged from 22 years to 53 years with mean values + SD of 42.6±10.6 years. S.creatinine and U IL-18 were measured basal at admission , 6 hours and 24 hours after. RESULTS: U IL-18 was significantly increased in AKI group after 6 hours compared to its basal values. Further increase of U IL-18 after 24 hours compared to both basal and 6 hours values. We also revealed that UIL-18 was higher in patients with AKI compared to patients without AKI. S.creatinine was not elevated in either groups after 6 hours. S.creatinine was significantly increased in AKI after 24 hours. We found that the sensitivity and specificity of U IL-18 at 6h from admission in ICU was 91.1% and 93.9% respectively. CONCLUSIONS: Urinary IL-18 (pg/dl) is significantly increased in AKI groups , this increase is earlier than any rise of serum creatinine in these patients . Urinary IL-18 is more specific and sensitive in prediction of AKI than serum creatinine , So urinary IL-18 can be used as an early biomarker of AKI in critically ill patients in ICU that may allow early prediction at a time when intensive care optimization can be performed and that can help in prevention of worsening of these cases and good outcome.