Biochemical markers in the prediction of contrast-induced acute kidney injury

: For many years clinicians have been searching for “kidney troponin”- a simple diagnostic tool to assess risk of acute kidney injury (AKI). Recently, the rise in the variety of contrast-related procedures (contrast computed tomography [CT], percutaneous coronary intervention [PCI] and angiography) have resulted in increased number of contrast-induced acute kidney injuries (CI-AKI). CI-AKI remains important cause of overall mortality, prolonged hospitalization and it increases total costs of therapy. The consequences of kidney dysfunction affect the quality of life and they may lead to disability as well. Despite extensive worldwide research, there are no sensitive and reliable method of CI-AKI prediction. Kidney Injury Molecule 1 (KIM-1) and Neutrophil Gelatinase Lipocalin (NGAL) have been considered as kidney specific molecules. High concentrations of these substances before the implementation contrast-related procedures have been suggested to enable the estimation of kidney vulnerability to CI-AKI and they seem to have predictive potential for cardiovascular events and overall mortality. According to other authors, routine determination of known inflammation factors (e.g. CRP, WBC, neutrophil count) may be helpful in prediction of CI-AKI. However, the results of clinical trials provide contrasting results. The pathomechanism of contrast-induced nephropathy remains unclear. Due to its prevalence, the evaluation of the risk of acute kidney injury remains serious problem to be solved. This paper reviews pathophysiology and suggested optimal markers facilitating the prediction of contrast-induced acute kidney injury.