[Differential diagnosis of acute kidney injury in critically ill patients: the nephrologist's role in identifying the different causes of parenchymal damage].

The management of acute kidney injury in the critical area is complex and necessarily multidisciplinary, but the nephrologist should maintain a pivotal role, both in terms of diagnosis and of indication, prescription and management of extracorporeal replacement therapy. The most frequent causes of AKI in the critically ill patients are correlated to sepsis and major surgery, but the incidence of different causes, of strict nephrological relevance, is probably higher than the estimate. Nephrologists have the competence to evaluate data relating to renal functions, urinary electrolytes, urinary sediment, and to identify which specific examinations can be useful to define the cause of AKI. A nephrological consultation will therefore improve the clinical management of AKI by guiding and integrating the diagnostic path with traditional or more advanced assessments, useful for the identification of the different causes of acute kidney damage and consequently of the most appropriate therapy. The etiological diagnosis of AKI will also be crucial in defining the renal prognosis and therefore an appropriate nephrological follow up.