By: Lourdes Trinidad Miranda Dominguez, MD, Fellow, Pathology & Laboratories
Laboratory automation has been a tremendous help in the advancement of the laboratory technology. It has been applied to different areas of laboratory processes such as instrumentation, hardware and software systems, data storage and retrieval, and other methodologies that facilitate, expedite and increase the efficiency in the delivery of services. This is especially true for laboratories with high demand in diagnostic testing.
Bacteriologic studies have long been done manually with tedious procedures and long turnaround times to perform microbial identification and sensitivity studies. With the advancement in laboratory technology, this has prompted the introduction of automation in the field of microbiology to lessen the laborious procedures and shorten the turnaround time.
MakatiMed’s Section of Clinical Microbiology of the Department of Pathology & Laboratories has recently shifted to automation with the acquisition of new machines that utilize improved technology.
VirtuO™ BacT/ALERT is an automated blood culture incubator that follows a colorimetric principle (a method of determining the concentration of a chemical element or compound in a solution with the aid of a color reagent) which has the following advantages: it has a visual growth indicator, which shows a noticeable permanent change in color once positive for bacterial growth. The color change is more stable, where continuous reading proceeds even when there is a delay in loading the bottle inside the machine. It uses safe, lightweight and unbreakable bottles. The culture bottles contain APB (Adsorbent Polymeric Beads) that can neutralize toxic blood components and neoplastic drugs that can interfere with testing. These features also provide enhanced recovery of pathogenic microorganisms on patient’s samples who are undergoing therapy and patients who are immune-compromised.
Previ™ Isola is an automated agar plate sample streaker that provides a standardized method of plate inoculation. Streaking is a technique used to isolate a pure strain from bacteria or other microorganisms, which can then be identified and tested. The automated streaker allows better and reproducible isolation of bacteria. It also offers flexibility in the process flow by allowing simultaneous handling of various types of samples and sample containers. There is no cross-contamination since it uses individualized sterile tips and applicator, which are disposed with each use on each plate. It also has additional built-in bar-code labels for easy traceability.
Samples sent for Gram stain evaluation, which is a test to identify the cause of bacterial infection, can now be done using the Previ™ Color Gram. This is a fully automated staining machine starting from fixation, staining, to drying of slides that is finished in 5 minutes. Staining is standardized, with less cross-contamination and with a cleaner background that provides better visualization of samples for microbial evaluation.
Rapid and timely identification of the pathogenic organism causing the infection is very important in the treatment and recovery of the patient. Vitek MS™ is a microbial identification method based on mass spectrometry that uses MALDI-TOF (Matrix Assisted Laser Desorption Ionization Time-of-Flight) technology. It can identify a wide array of organisms such as bacteria, yeasts, molds and Mycobacterium species through comparison of the isolate information with that stored in its broad databank. Vitek MS™ can deliver its result in 15 minutes, which shortens the identification testing process to 24 hours, from the previous 48-hour waiting period. With the rapid identification of microbial pathogens, clinicians can deliver swift treatment decisions for their patients.
Antimicrobial susceptibility tests, also called sensitivity testing or drug resistance testing, are used to determine which specific antibiotics will be effective in stopping the infection. The result can then guide the clinicians as to what type of antimicrobial can be given to the patient. Vitek 2™ XL is a fully automated sensitivity testing method based on the Minimum Inhibitory Concentration (MIC) technique. Traditionally, MICs are determined through a tedious and time-consuming process. With automation, interpretation is standardized, thus minimizing differences in analysis that may occur during manual reading and interpretation of results. Vitek 2™ XL conforms to the EUCAST and CLSI antibiotic susceptibility testing MIC-based reference standards. It can produce results after 16 to 24 hour standard incubation of an organism taken from a well-isolated 24-hour-old colony. It has a bar coding system that saves time in encoding patient information and provides traceability of the patient isolates and test cards when retrieval is needed.
Definitely, automation is a major advancement in the process flow of the microbiology laboratory. It has improved the standardization of the processing of samples as well as the interpretation of results. It has shortened the turn-around time in the identification of isolated pathogenic organisms, which now gives a more definitive treatment option for clinicians and their patients.