Abstract
Medical microbiology involves the identification of microorganisms for the diagnosis of infectious diseases and the assessment of likely response to specific therapeutic interventions. Major categories of organisms include bacteria, mycobacteria, fungi, viruses, and parasites. Microbiological methods combined with clinical symptoms, additional laboratory tests, and imaging techniques are used in combination to distinguish a true disease-associated infection from colonization with normal flora or other conditions, such as malignancies, inflammatory disorders, or autoimmune disorders, all of which have unique therapies and prognoses for the patient. Laboratories combine the use of traditional microscopy and culture methods, with a rapidly evolving set of molecular and proteomic techniques. Given the increase in immunocompromised patients due to an increase in transplantations, the human immunodeficiency virus epidemic, and the use of immunosuppressive agents to treat autoimmune disorders, diagnosis of microbial infections continues to be essential for many patients.