A method for (i) diagnosing or monitoring kidney function in a subject or (ii) diagnosing kidney disease or renal complications prior to the onset of kidney degeneration in a subject or (iii) predicting or monitoring the risk of an adverse event in a subject with kidney disease wherein said adverse event is selected from the group comprising worsening of kidney dysfunction including kidney failure, loss of kidney function, development of related comorbid condition, end-stage kidney disease, or death, or (iv) predicting or monitoring the success of a therapy or intervention in a subject with kidney disease, the method comprising:
- (a) measuring a level or amount of prouroguanylin (proUGN) in a biological sample, (b) comparing the measurement to a control reference range or threshold value, (c) determining whether the measurement of proUGN is above the control reference range or threshold value, and if so, (d) providing clinical care and treatment to the subject or according to (iv), modifying the therapy or intervention.