Identification of diagnostic urinary biomarkers for acute kidney injury.
Acute kidney injury (AKI) is an important cause of death among hospitalized patients. The 2 most common causes of AKI are acute tubular necrosis (ATN) and prerenal azotemia (PRA). Appropriate diagnosis of the disease is important but often difficult. We analyzed urine proteins by 2-dimensional gel electrophoresis from 38 patients with AKI. Patients were randomly assigned to a training set, an internal test set, or an external validation set. Spot abundances were analyzed by artificial neural networks to identify biomarkers that differentiate between ATN and PRA. When the trained neural network algorithm was tested against the training data, it identified the diagnosis for 16 of 18 patients in the training set and all 10 patients in the internal test set. The accuracy was validated in the novel external set of patients where conditions of 9 of 10 patients were correctly diagnosed including 5 of 5 with ATN and 4 of 5 with PRA. Plasma retinol-binding protein was identified in 1 spot and a fragment of albumin and plasma retinol-binding protein in the other. These proteins are candidate markers for diagnostic assays of AKI.
Varghese
Sanju A
SA
Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, USA.
Powell
Thomas B
TB
Janech
Michael G
MG
Budisavljevic
Milos N
MN
Stanislaus
Romesh C
RC
Almeida
Jonas S
JS
Arthur
John M
JM
D058186:Acute Kidney Injury / Q000209:etiology / Q000652:urine*; D000465:Algorithms; D053099:Azotemia / Q000150:complications / Q000652:urine*; D015415:Biomarkers / Q000097:blood / Q000652:urine*; D003937:Diagnosis, Differential; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D006801:Humans; D007683:Kidney Tubular Necrosis, Acute / Q000150:complications / Q000652:urine*; D008297:Male; D008875:Middle Aged; D016571:Neural Networks, Computer; D011237:Predictive Value of Tests; D040901:Proteomics; D015203:Reproducibility of Results; D054839:Retinol-Binding Proteins, Plasma / Q000032:analysis; D012709:Serum Albumin / Q000032:analysis; D016482:Urinalysis / Q000379:methods
D015415:Biomarkers; D054839:Retinol-Binding Proteins, Plasma; D012709:Serum Albumin