[Incidental Proteinuria - Interpretation and Diagnosis].

Incidental Proteinuria - Interpretation and Diagnosis Abstract. The incidental finding of proteinuria is common in daily clinical practice. In most cases, this is the result of a urinary dipstick test. When proteinuria is discovered as a coincidental finding, there are basically two scenarios: The dipstick test can be false or true positive. If the test is a true positive, a distinction needs to be made as to whether the proteinuria incidentally discovered is the result of a benign cause or a cause that requires further examinations or specific therapy. Therefore, in order to avoid unnecessary examinations, false positive results and benign causes such as contamination or extrarenal causes, temporary proteinuria or orthostatic proteinuria should be excluded in a first step. If there is persistent proteinuria with no obvious benign cause, the next step is to distinguish common from rare causes. It should always be explored whether there is diabetes mellitus, arterial hypertension or other cardiovascular risk factors that can explain the appearance of proteinuria. Regardless, when diagnosing persistent proteinuria for the first time, a basic assessment should be carried out, that includes serum creatinine, urinary sediment and sonography of the urinary tract. If the cause remains unclear, a kidney biopsy should be done without hesitation.