The systems approach to diagnostic microbiology.

"Classical" and "conventional" methods for microbial identification are still utilized in clinical microbiology laboratories; however, significant advances in methodology have taken place in the last two decades. In the transition from classical to contemporary methodologies, the reference point has changed from multistep procedures to unitary procedures with marked emphasis on standardization, speed, reproducibility, and most recently, mechanization and automation. The most evident expression of this transition is the adaptation or streamlining of classical methods in the form of "miniaturized identification systems" and their commercial availability. This review analyzes the development of the underlining principles that make the systems approach to diagnostic microbiology possible.