Newer diagnostic tests for bacterial diseases

In diagnosing bacterial infections, the rapid identification of bacteremia at an early stage of the disease is critical for a favorable outcome. Furthermore, it is important that exact information be obtained on the stage of the disease rapidly in order to choose and initiate the appropriate therapy. In recent years many new techniques have been added in the diagnostic tools. During the past decade, there has been unprecedented progress in molecular biology as well as in the application of nucleic acid technology to the study of the epidemiology of human infection. Highly sensitive molecular techniques are found to be capable of detecting minute amounts of specific microbial DNA sequences and their complex genetic variations. Moreover, altered levels of biomarkers such as procalcitonin, C-reactive protein, tumor necrosis factor alpha, and several interleukins are also found to be promising to define systemic inflammatory response syndrome as indirect evidences of bacterial infections. Lastly, many rapid culture methods are coming up to achieve faster bacterial diagnosis. In this review we will focus on these three newer methods for the early diagnosis of bacterial infections. These approaches will help to expedite the diagnosis of especially early infections and might be a further step towards the improvement of therapeutic methods.