Medically Important Anaerobes
Continuing Education Credits
Objectives
- Describe the clinical significance of medically important anaerobic bacteria.
- Describe the general characteristics and growth requirements of anaerobic bacteria.
- Describe proper collection procedures and acceptable patient specimens, as well as the types of culture media and special conditions required for the propagation of medically important anaerobic bacteria.
- Explain the basic Gram stain reaction and significant differences between commonly encountered anaerobe genera: Actinomyces, Bacteroides, Bifidobacterium, Clostridium, Cutibacterium (Propionibacterium), Fusobacterium, Peptostreptococcus, Porphyromonas, Prevotella, and Veillonella.
- Compare and contrast different identification and susceptibility testing methods reserved for medically important anaerobic bacteria.
Course Outline
- Introduction to Medically Important Anaerobic Bacteria
- Discovery of Anaerobic Bacteria
- Louis Pasteur is credited with what important discovery in the late 1800s?
- Clinical Significance
- Clinical Significance
- In humans, anaerobes are part of the normal flora of all of the following body site locations except:
- Select the correct statement regarding the way anaerobic bacteria enter the body as pathogens:
- General Characteristics and Growth Requirements
- General Characteristics and Growth Requirements
- Obligate anaerobes may be subdivided into strict and moderate obligate anaerobes. Strict obligate anaerobes:
- Aerobic and anaerobic bacteria categories may overlap when describing oxygen requirements for growth. In which categorization is this overlap seen?
- Proper Specimen Collection and Transport Procedures
- Specimen Collection and Transport
- Acceptable and Unacceptable Specimens
- During the collection and transport stages of the anaerobic culturing technique, which of the following is an acceptable practice?
- Which of the following is considered an unacceptable specimen for anaerobic culture?
- Specimen Preparation, Media, and Incubation
- Visual Inspection of the Specimen Submitted for Culture
- Specimen Preparation
- Special Media
- Inoculation and Incubation
- Anaerobic Conditions
- Aerotolerance Testing
- With regard to visual inspection of a specimen submitted for anaerobic culture, the presence of sulfur granules refers to:
- All of the following may be considered ways to achieve an oxygen-free environment except:
- Some Commonly Encountered Anaerobes
- Overview of Commonly Encountered Anaerobes
- Table of Commonly Encountered Anaerobes
- What is the currently accepted nomenclature for Propionibacteria acnes?
- Actinomyces
- Actinomyces
- Bacteroides
- Bacteroides
- Bifidobacterium
- Bifidobacterium
- Clostridium
- Clostridium
- Clostridium, continued
- Spores
- Toxin production in some Clostridium species may cause extensive harm to humans. Toxin from which species is associated with lockjaw?
- Cutibacterium (Propionibacterium)
- Cutibacterium (Propionibacterium)
- Fusobacterium
- Fusobacterium
- Peptostreptococcus
- Peptostreptococcus
- Which of the following statements is true regarding the genus Peptostreptococcus?
- Porphyromonas
- Porphyromonas
- Prevotella
- Prevotella
- Veillonella
- Veillonella
- Regarding the genus known as Veillonella:
- Identification and Susceptibility Testing Methods
- Gram Reaction
- General Questions to Ask During the Workup of Anaerobic Cultures
- Workup: Basic Flow
- A Gram stain on an anaerobic blood agar plate revealed pure, large gram-negative rods with what appeared to be spores. Concurrent Gram stain quality control was acceptable. No growth was noted on the aerobic blood agar plate. The clinician was expecting a report of Clostridium. What might have gone wrong?
- Identification
- Identification Methods
- Identification Methods, continued
- One limitation of using rapid tests and disks for presumptive identification of anaerobic isolates is:
- Select the correct statement regarding the identification of anaerobes using the MALDI-TOF method:
- Susceptibility Testing
- Susceptibility Testing Methods
- In addition to using the manufacturer's standard operating procedures, a good resource to use when performing anaerobic susceptibility testing (or viewing known antibiograms) is:
- Summary
- Algorithm for Workup
- Algorithm for Workup, continued
- Final Thoughts
- References
- References
Additional Information
Level of Instruction: Basic to Intermediate
Intended Audience: Medical laboratory scientists and medical laboratory technicians in medical microbiology/bacteriology. This course is also appropriate for MLS and MLT students and pathology residents.
Author Information: Dr. Julie Ann West is certified by the American Society for Clinical Pathology (ASCP) as a Medical Laboratory Scientist (MLS) and as a Specialist in Microbiology (SM). In addition, Dr. West has earned a PhD in Public Health - Infectious Disease Epidemiology - and is Certified in Public Health (CPH) by the National Board of Public Health Examiners. Dr. West is experienced as a Technical Specialist, Safety Officer, Educator, and Lead in the Veterans Administration Healthcare System, and has prior experience as an Administrative Laboratory Director.
Reviewer Information: Hallee Waye, MS, MLS (ASCP)CM, has over 10 years of experience as a medical laboratory scientist. She has clinical experience in blood bank, microbiology, chemistry, hematology, urinalysis, and coagulation. She currently works as a clinical microbiologist and MLS Program Director for the Parkview School of Medical Laboratory Science in Pueblo, Colorado. She obtained her bachelor’s degree in microbiology from Colorado State University, attended the Colorado Center for Medical Laboratory Science to obtain her professional certificate in medical laboratory science, and completed her master’s degree in clinical laboratory science at the University of Texas Rio Grande Valley.
Course Description: This course provides a basic understanding of medically important anaerobic bacteria. Clinical significance, general characteristics, and culture growth requirements are explained. The types of acceptable patient specimens, proper specimen collection procedures, media, and special conditions/handling are described. In addition, basic Gram stain reaction and significant differences between several commonly encountered anaerobes are explained. The identification and susceptibility testing methods for medically important anaerobic bacteria are compared and contrasted.