In critical units, prediction of outcome is of vital importance to the intensivist. It allows planning of early therapeutic interventions, optimal resource allocation and appropriate counselling of the family and/or patient. Critical illnesses are more often characterised by the Systemic Inflammatory Response Syndrome (SIRS), the host response to an acute insult. SIRS is a common finding in the ICU patients, which when severe can lead to Multiple System Organ failure (MSOF) and finally death. A very early feature of inflammation is increased capillary permeability to plasma proteins which occur within few minutes of injury and usually returns to normal within 6-12 hours. A severe and sustained inflammatory reaction induces rapid and profound changes in the endothelium resulting in the loss of barrier integrity leading to systemic capillary leak. In the Kidneys these manifests as altered glomerular permeability culminating in increased renal albumin excretion in the urine. The degree of albuminuria is variable and in most instances may not be clinically detectable using rapid dipstick testing. Such low rates albumin excretion (<300 mg/day) are termed Microalbuminuria.