A prospect of current microbial diagnosis methods

An accurate identification and characterization of pathogens is crucial in disease management. The appropriateness and effectiveness of the microbial diagnosis method influence the choice of the antimicrobial agent to be used in the treatment of infection. Traditionally, bacterial diagnosis is based on conventional and culturing-dependent approaches, such as culture and counting methods, generally coupled to morphological and physiological characterization. Currently, rapid technological advances in bacterial identification methods are occurring providing a bewildering wide range of techniques to detect, identify and differentiate bacteria. Molecular methods, such as ELISA and PCR, had introduced great improvements in bacterial identification as they contributed to speed up the analysis and the reduction of handling. However, it has been demonstrated that heterogeneous microbial communities are the main cause of several human infections. This genetic and phenotypic heterogeneity is crucial to microorganisms achieving adaptation to human host, and it might reflect distinct pathogenicity potential. The aforementioned molecular methods and new emergent methods, such as MALDI-TOF MS, have still limitations in full identification and differentiation of microbial heterogeneity. Therefore, a new generation of diagnosis methods able to detect and characterize microbial heterogeneity should be developed. Microbial infections are like dynamic systems and it is essential that diagnosis methods and technologies rapidly evolve to detect and measure changes occurring at individual and population level. This new kind of methods will allow a relevant shift about infection development understanding, as well about microbial mechanisms of resistance to antibiotics and human defences and persistence ability in human host that culminate in better medical decisions about antimicrobial therapy.