Drug-induced nephrotoxicity accounts for 20% of hospital and community-acquired acute kidney injury (AKI). Nephrotoxic drugs could induce tubular cell necrosis and renal failure. Few studies have evaluated AKI and its consequences in patients with acute poisoning. This study aimed to assess the urinary tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein-7 (IGFBP-7) as diagnostic and prognostic markers of AKI in critically ill, acutely poisoned patients.

We conducted a prospective study including all critically ill poisoned adult patients admitted to the ICU of the Poison Control Centre, Ain-Shams University Hospitals from September 2022 to June 2023.

TIMP-2, IGFBP-7, and their multiplication product (TIMP×IGFB/1000) can differentiate between AKI and non-AKI with an AUC of 0.996, 0.990, and 0.995, respectively. They were significantly higher in AKI, stage 3. TIMP-2 was significantly higher among patients who required mechanical ventilation (n=26, 65%). Both biomarkers and their product were significantly higher among the non-survivors (27.5%). They showed a positive correlation with serum BUN, creatinine levels, length of ICU stay, poisoning severity score, as well as sequential organ failure assessment (SOFA) and Simplified Acute Physiology Score (SAPS II) scores. TIMP-2, IGFBP-7, and TIMP×IGFB/1000 are useful in the early prediction of the development and progression of AKI in acutely intoxicated patients.

Combining clinical scores with biomarkers helps in stratifying the severity and mortality risk associated with AKI.