Which laboratory technique is most commonly used to identify bacterial infections?

Culture and sensitivity testing is the preferred laboratory technique for identifying bacterial infections due to its ability to isolate and grow microorganisms from a clinical specimen. This method involves placing a sample on a growth medium that supports bacterial growth, allowing the laboratory technician to identify the specific type of bacteria present based on colony morphology, color, and other characteristics. Additionally, sensitivity testing can determine which antibiotics are effective against the identified bacteria, providing crucial information for treatment decisions.

This technique is foundational in microbiology because it not only helps confirm the presence of a bacterial pathogen but also informs about its susceptibility to various antimicrobial agents, thereby guiding appropriate therapy. While methods like polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA) provide valuable information, they are often used for specific purposes—PCR for detecting bacterial DNA and ELISA for measuring immune responses, respectively. Western blotting is primarily a technique for detecting proteins and is not typically employed for direct bacterial identification.