Gene expression profiling and biomarkers in ARDS

I. Genomic and Proteomic Approaches to the Study of ARDS Although the cute respiratory distress syndrome (ARDS) was described 40 years ago, the advances in diagnostic and treatment options have been progressing slowly. Part of the reason for this slow pace is due to the difficulty in establishing a method for the unbiased diagnosis of this syndrome. Currently, the diagnosis of ARDS/acute lung injury (ALI) is clinical, and is described according to the American-European Consensus Conference (AECC) definition by a series of clinical findings including acute onset, severe hypoxemia, the presence of bilateral pulmonary infiltrates, and no evidence of heart failure (1). However, there are several problems with the current clinical criteria for diagnosis. One problem is that there has been found to be a large degree of interobserver variability in applying the radiographic criteria to the diagnosis of ARDS (2). This large degree of variability makes it difficult to identify subsets of patients with the potential to benefit from more targeted therapy, and also makes it difficult to select patients for ongoing clinical trials. Furthermore, the difficulty in identifying patients with the disease makes it difficult to further the understanding of the pathogenesis of this disease in certain groups of patients, such as those with sepsis, trauma, pancreatitis, and certain types of surgery. Another problem with the AECC clinical diagnosis of ARDS is that attempts to validate the clinical criteria by comparison with pathologic findings have revealed that the accuracy of the clinical diagnosis is only moderate when compared to the pathologic diagnosis of diffuse alveolar damage (3).