Principles of microscopy, culture and serology-based diagnostics

The increasing rates of antibiotic resistance justify the need for microbiological investigations of patients with infections. Despite rapid advances in molecular diagnostics, traditional methods of microscopy, culture and serology still play a major role in the diagnosis of infectious diseases. Developments in differential media and the introduction of automated techniques for identification, susceptibility testing and serological diagnosis have improved efficiency. Many specimens are now examined using a combination of these older techniques and newer molecular methods. This article gives an overview of the use of microscopy, culture, antimicrobial susceptibility testing, serology and antigen detection techniques, with examples of how these methods are combined in the analysis of specimens.