Kidney injury molecule-1 as an early detection tool for acute kidney injury and other kidney diseases.

INTRODUCTION: Although change in serum creatinine is the standard metric tool for the detection of renal injury, its lack of sensitivity has made the early diagnosis of acute kidney injury (AKI) very difficult. In fact, the absence of sensitive AKI biomarkers has impaired progress in the nephrology field and had a detrimental effect on the design and outcome of AKI clinical trials. Recently, several proteins have shown potential in the early detection of acute and chronic kidney injuries. AREAS COVERED: This review discusses the current status of kidney injury molecule-1 (KIM-1) as a potential diagnostic tool in patients with various acute and chronic kidney diseases. The focus is limited to human studies from January 2002 to July 2010. The review clarifies the clinical conditions for which KIM-1 has the greatest potential utility for early detection of kidney injury. It also demonstrates to the reader the barriers to the successful use of KIM-1 and other biomarkers in clinical practice, and the future trials that will be needed to validate their use. EXPERT OPINION: Despite the early promise of biomarkers such as KIM-1 for the early detection and prognosis of kidney disease, more studies are required to establish their utility in clinical practice. Indeed, the published clinical studies of urine KIM-1 so far are small and insufficient to support urinary KIM-1 as an effective AKI diagnostic test in humans. It is suggested, through the heterogeneity of AKI and existing published data, that more than one biomarker may be necessary to obtain sufficient sensitivity and specificity for AKI screening.