Risk Factors and Early Diagnosis of Acute Renal Impairment in Patients with Sepsis

Abstract

AKI is a serious and common clinical problem in the ICU, even mild forms of AKI are associated with high mortality rates. The term AKI has replaced ARF, with the understanding that the spectrum of AKI is broad and includes different degrees of severity. A new classification system, known as the RIFLE system, can be used to identify kidney injury and outcome. New biomarkers are being studied to replace conventional markers such as urea and creatinine, but although the markers appear to hold promise in identifying kidney injury, they still are not commonly available and require more study. Methods to prevent AKI include maintenance of fluid volume, renal perfusion pressure, avoidance of nephrotoxic agents, and treatment of AKI by dialysis methods after careful assessment of the patient and the clinical picture. Use of a variety of methods to prevent AKI, including renal replacement therapies, may improve the outcome from AKI. Sepsis is a severe and dysregulated inflammatory response to infection characterized by end-organ dysfunction distant from the primary site of infection. Development of acute kidney injury (AKI) during sepsis increases patient morbidity, predicts higher mortality, has a significant effect on multiple organ functions, is associated with an increased length of stay in the intensive care unit, and hence consumes considerable healthcare resources. When compared with AKI of nonseptic origin, septic AKI is characterized by a distinct patho-physiology and therefore requires a different approach. Despite impressive advances in several fields of medicine, the patho-physiology, diagnostic procedures, and appropriate therapeutic interventions in sepsis are still highly debatable. Numerous immune-modulatory agents showing promise in preclinical studies fail to reduce the over-whelmingly high mortality rate of sepsis and provoke AKI when compared with other critically ill patients. Major impediments to progress in understanding, early diagnosis, and application of appropriate therapeutic modalities in sepsis-induced AKI include limited histo-pathologic information, few animal models that closely mimic human sepsis, and a relative shortage of specific diagnostic tools.