Acute renal failure (ARF) is a frequent problem in the intensive care unit and is associated with a high mortality. Early recognition could help clinical management, but current indices lack sufficient predictive value for ARF. Therefore, there might be a need for biomarkers in detecting renal tubular injury and/or dysfunction at an early stage before a decline in glomerular filtration rate is noted by an increased serum creatinine. A MEDLINE/PubMed search was performed, including all articles about biomarkers for ARF. All publication types, human and animal studies, or subsets were searched in English language. An extraction of relevant articles was made for the purpose of this narrative review. These biomarkers include tubular enzymes (alpha- and pi-glutathione S-transferase, N-acetyl-glucosaminidase, alkaline phosphatase, gamma-glutamyl transpeptidase, Ala-(Leu-Gly)-aminopeptidase, and fructose-1,6-biphosphatase), low-molecular weight urinary proteins (alpha1- and beta2-microglobulin, retinol-binding protein, adenosine deaminase-binding protein, and cystatin C), Na+/H+ exchanger, neutrophil gelatinase-associated lipocalin, cysteine-rich protein 61, kidney injury molecule 1, urinary interleukins/adhesion molecules, and markers of glomerular filtration such as proatrial natriuretic peptide (1-98) and cystatin C. These biomarkers, detected in urine or serum shortly after tubular injury, have been suggested to contribute to prediction of ARF and need for renal replacement therapy. However, excretion of these biomarkers may also increase after reversible and mild dysfunction and may not necessarily be associated with persistent or irreversible damage. Large prospective studies in human are needed to demonstrate an improved outcome of biomarker-driven management of the patient at risk for ARF.

Acute renal failure (ARF) necessitating renal replacement therapy is a common problem associated with high morbidity and mortality in the critically ill. Hypotension, followed by resuscitation, is the most common etiologic factor, mimicked by ischemia/reperfusion (I/R) in animal models. Although knowledge of the pathophysiology of ARF in the course of this condition is increasingly detailed, the intracellular and molecular mechanisms leading to ARF are still incompletely understood. This review aims at describing the role of cellular events and signals, including collapse of the cytoskeleton, mitochondrial and nuclear changes, in mediating cell dysfunction, programmed cell death (apoptosis), necrosis and others. Insight into the molecular pathways in the various elements of the kidney, such as vascular endothelium and smooth muscle and tubular epithelium leading to cell damage upon I/R will, hopefully, open new therapeutic modalities, to mitigate the development of ARF after hypotensive episodes and to promote repair and resumption of renal function once ARF has developed.

Objective To determine if mycophenolate mofetil (MMF) diminishes skin and muscle disease activity in children with juvenile dermatomyositis (DM), thereby permitting a decrease in corticosteroid dose. Methods A retrospective data review for 50 children with juvenile DM (mean ± SD age 12.2 ± 5.0 years) who had received MMF for 12 months identified the following characteristics: 38 (76%) were girls, 39 (78%) were white, 10 (20%) were Hispanic, and 1 (2%) was African American. The MMF dose and frequency, type of infection, white blood cell (WBC) count, corticosteroid dose, and the validated disease activity score (DAS) subscores for skin (DAS‐S) and muscle (DAS‐M) were obtained. Results Twelve months after the start of MMF, the mean ± SD DAS‐S decreased from 5.24 ± 0.29 to 3.72 ± 0.29 (P = 0.001), and the mean ± SD DAS‐M decreased from 2.44 ± 0.39 to 1.17 ± 0.28 (P = 0.002). The mean ± SD prednisone dosage decreased from 0.39 ± 0.06 to 0.23 ± 0.02 mg/kg/day (P = 0.0001), with resumption of linear growth (P = 0.008). The WBC/lymphocyte count was unchanged over the 12 months on MMF. The infection rate was assessed in a subset of 26 children with juvenile DM who were observed for 12 months before the start of MMF and then compared with the ensuing 12 months of MMF therapy. There was no significant difference between the pretreatment period and the first 6 months of MMF therapy (P = 0.44), but the infection rate decreased in months 7–12 (P = 0.001). Conclusion MMF appears to be worthy of consideration as an additional therapeutic modality for treatment of children with juvenile DM. These data suggest that the use of MMF decreases skin and muscle disease activity and is steroid sparing. MMF appears to be well tolerated, but patients should be monitored for infection.