Urinary α-GST and π-GST for prediction of dialysis requirement or in-hospital death in established acute kidney injury

Abstract

Context: Urinary α-glutathione S-transferase (α-GST) and π-glutathione S-transferase (π-GST) are promising proximal and distal tubular leakage markers for early detection of acute kidney injury (AKI).

Objective: To examine the performance of these markers for predicting the composite of dialysis requirement or in-hospital death in patients with an established diagnosis of AKI.

Materials and methods: Prospective cohort study of 245 adults with AKI. A single urinary α-GST and π-GST measurement was obtained at time of nephrology consultation.

Results: Overall, urinary π-GST performed better than α-GST for prediction of dialysis requirement (AUC 0.59 vs. 0.56), and the composite outcome (AUC 0.58 vs. 0.56). In subgroup analyses, π-GST displayed better discrimination for prediction of dialysis requirement in patients with baseline eGFR <60 mL/min/1.73 m² (AUC 0.61) and oliguria (AUC 0.72). Similarly, α-GST performed better in patients with stage-1 (AUC 0.66) and stage-2 AKI (AUC 0.80).

Conclusions: In patients with an established diagnosis of AKI, a single urinary π-GST measurement performed better than α-GST at predicting dialysis requirement or death, but neither marker had good prognostic discrimination.

Keywords::

• Acute kidney injury
• acute renal failure
• biomarker
• glutathione S-transferase
• epidemiology
• prognosis