Iupac Automation and Mechanization in Clinical Microbiology

It is widely recognized that the diagnostic clinical laboratory has been revolutionized during recent years by extraordinary progress and instrumentation in automation. The microbiology and immunology laboratories have not developed until quite recently a sophisticated instrumentation and automation methodology. However, such advances are dependent on both modification and expansion of conventional techniques and on development of refined equipment to perform many of the time consuming but necessary manual operations. A variety of newer automated technologies are briefly described and discussed. It is quite apparent that a clinical microbiology and immunology laboratory depends not only upon application of modern technology but also interpretive ability and rational decision making as to what are clinically relevant determinations. Like many of the other clinical laboratory specialties, the clinical microbiology laboratory provides a diagnostic function by evaluating results obtained with clinical specimens as well as comparing these results with expectations and knowledge about infectious diseases. Microbiology per se has been one of the most difficult of the clinical laboratory specialties to adjust to automation and/or instrumentation. There are many reasons for this. Firstly, micro— organisms responsible for human diseases often require multiple testing for identification; these necessary tests are often difficult to mechanize and/or automate. In addition, the microbiologist must obtain information concerning morphology, clonal characteristics, and other features of the organism. Also, one must know about the source of the specimen, the patient's medical history and any other pertinent information which will assist diagnosis. Additionally, many specimens obtained from tissues or fluids may contain normal microbial flora necessitating the separation of these micrQorganisms from those which may be pathogenic or opportunistic. The identification of pathogens also usually demands considerably more information than provided by a single or even a few tests. Different methodologies are typically required to completely characterize any given bacterial isolate, including growth requirements, chemical reactivity and serologic typing. Instruments designed to detect the growth of a microorganism or for identification cannot be made universally applicable, since growth requirements of such microbial groups as aerobic versus anaerobic bacteria as well as nonfastidious versus fastidious organisms are often quite different. In addition, among the problems complicating instrumental isolation and identification of microorganisms are that disease producing microbes in patient specimens are often present in insufficient number to insure their identification through the usual instruments without resorting to enhancement or propagation of their growth through culture. Besides this, many microorganisms replicate so slowly that they require days or even weeks rather than hours for colony formation, delaying the completion time of a given test. Because of this, much of the effort in developing instrumentation for microbiology has focused on methods for detecting organisms in a specimen that should only be sterile, such as blood, cerebrospinal fluid or urine, rather than identifying these organisms. Other instrumentation, for determining whether organisms in a positive isolate are susceptible to antibiotics has been developed, and automated equipment providing relatively rapid antibiotic susceptibility tests are now available. Finally, instruments designed to identify microorganisms by various biochemical and physico—chemical tests are now being developed and there is substantial hope that they may be found useful in the clinical microbiology laboratory. An additional approach to identification of microorganisms or microbial infections involves the use of specific antibodies. Thus, in terms of infectious diseases, serology and clinical inununology have developed parallel to classic microbiology. In recent years, it has become quite clear that a wide variety of immunologic tests are available not only for infectious diseases, but also for many immunopathologic conditions, including autoinimune and inununodeficiency diseases and even for cancer. Yet, although the earliest immunologic tests were based on assays that could be detected by instrumentation or automation, it has