How Visual Tools Help Learners Conquer Clinical Microbiology
Microbiology is a beautiful science: swimming trypanosomes, sporulating fungi, colorful agar and bacteria that "rocket," "tumble" and "splash." But there's a lot to know about these tiny organisms, and those starting careers in microbiology can be understandably daunted by the steep learning curve. It takes just one look at the Manual of Clinical Microbiology (now ClinMicroNow) or Bergey's Manual of Systematic Bacteriology: endless pages of tables with biochemical test results and obscure species. So, where does one start to advance from novice to expert?
In a field as visual as microbiology, visuals can themselves be highly effective tools to build expertise. Bloom's Taxonomy depicts knowledge progression as a pyramid, starting with "remembering" and "understanding" and advancing to higher-order skills, such as "evaluating" and "creating." Consider which skills the unenviable task of memorizing textbook tables builds: this approach expands base knowledge, but expertise comes from climbing the pyramid. There are strategic ways to do this. Like many others, I learn trends and exceptions more easily than I memorize tables. When I approach daunting new topics, I transform information into visual summaries, creating a tangible new product. "Creating" is the pinnacle of Bloom’s Taxonomy, and creating a visual tool strengthens each skill below. The process helps me build an increasingly complete understanding of clinical microbiology and was invaluable in my fellowship. The resulting visuals demonstrate how anyone can strategically learn (or teach) clinical microbiology, without memorizing the textbooks.
Visual tools can help learners climb the pyramid by precisely addressing the traits that distinguish experts from novices. According to How People Learn from the National Research Council, experts can identify patterns, organize their knowledge, identify when certain information is useful and retrieve it without great effort. Visuals are intuitive tools to develop all 4 of these traits, and thereby build expertise. Furthermore, at the educator and institution levels, visuals can be valuable tools to teach microbiology, as even the most well-meaning experts in microbiology may not be experts in pedagogy. The following framework explores how expert traits can be strategically addressed by visual tools to help learners build a practical microbiology understanding that is directly transferable to the many careers in the field.
1. Identify Patterns to Simplify Complex Information
Given an information-dense table, experts can identify what information is meaningful, whereas novices struggle. Visuals can be excellent tools to identify patterns when learning, or to illustrate them when teaching. The following is an example of a visual that highlights the meaningful methods to differentiate clinically relevant Pseudomonas species (versus the dense original source material). To create and teach this content, I included only the key tests and highlighted the most important ones (e.g., pyoverdin production), excluding tests that are rarely used for this purpose. By further clustering species into meaningful groups, the visual becomes even more digestible. As a result, a novice can more easily identify the meaningful patterns to distinguish pseudomonads and retrieve this knowledge more fluently, while the source remains available for more detailed learning or reference.
In this second example, prolific microbiology teacher and co-creator of PathElective.com Cullen Lilley, M.S., MB(ASCP), MDxT(AAB), has illustrated 3 traits to differentiate microfilarial nematode worms: sheath, nuclei and shape. Because these traits are seen in the tail, Lilley excludes the rest of the worm from the image to focus on the meaningful differences. By organizing this information into a flowchart, Lilley provides a clear approach. Finally, he "cues" the learner on when this information is relevant, based on the specimen type where each worm would be found. As a result, this tool is a helpful guide both for learners and at the parasitology bench.
2. Organize Knowledge to Connect Related Concepts
A second learnable expert trait is the organization of knowledge according to key concepts and relatedness to other concepts. The visual below organizes arthropod-borne bacterial genera according to their phylogenetic relatedness. Related concepts are connected using icons and arrows to link each species group with the diseases they cause and their arthropod vectors. The visual selectively distills information on nearly 50 species by defining meaningful groups and demonstrating connections between vectors, zoonoses and diseases. As an advancing novice, creating visuals like this helps me approach my own learning strategically. For instance, this visual helps exceptions that are not tick-borne stand out more clearly, such as the louse-borne Borrelia spp., or the flea-borne member of the spotted fever Rickettsia.
3. Cue Information As It Becomes Relevant to Build a Better Differential Diagnosis
Microbiologists commonly organize bacteria by their appearance on Gram stain. Infectious diseases physician Dr. Varun Phadke uses this framework to illustrate an approach to bacteria detected in blood cultures that he learned from his microbiology mentor, Dr. Colleen Kraft. When a microbe is first detected from a patient's blood culture, an expert can use information like the Gram stain to begin to intuit whether the microbe seen is most likely causing disease or merely a skin contaminant introduced during sample collection. This process is based on learned connections and context, but it can be challenging to teach a novice the precise "condition-action" pairs, or "if-then" statements, to develop this skill themselves.
To teach this "intangible" skill, Phadke organized his knowledge to create this straightforward visual tool, first illustrating the possible preliminary microbiology reports (i.e., Gram stain results), then introducing each row of the table in gradually increasing complexity. Phadke identifies which parameters matter more or less, providing "if-then" pairs to review bacterial shape in more detail, growth in the anaerobic vial or the time to positivity, as relevant. As a result, a novice can organize their knowledge by Gram stain and learn to cue the appropriate knowledge accordingly.
The Clinical Problem Solvers team takes a similar approach in building clinical schemas for various syndromes. Below, emergency physician Dr. Rabih Geha presents a visual approach to a patient presenting with a fever following travel. By organizing this as a flowchart, he provides a logical framework to a multifactorial reasoning process, starting with travel-related versus -unrelated causes of fever. Importantly, this schema highlights specific contexts that whittle down a long differential diagnosis to one that is a more focused by considering location(s), host status, exposure and time since travel. This approach activates other knowledge, including red flags for particular pathogens of concern, by explicitly tying these pathogens and contexts into the schema.
Geha expands upon this static visual by providing a dynamic framework with a "spotlight" approach, shown below and explained stepwise in his tutorial. This spotlight approach demonstrates how context can change a differential diagnosis, noting that "common things are common," and demonstrating how other contexts might change—or rather, add to—a differential. This spotlight approach provides a flexible framework to tackle new situations and allows the learner to better cue their knowledge, as appropriate, and critically evaluate the relative risk of certain pathogens.
4. Retrieve Knowledge More Efficiently to Stay Current with the Constantly Changing Taxonomy
Microbiologists work in a knowledge economy where—thanks to DNA sequencing and mass spectrometry—taxonomy is constantly changing. As instrument databases begin to report results with current nomenclature and interpret results so that physicians receive meaningful results, visual aids can help microbiologists stay current with updates to microbial taxonomy.
For instance, many changes were recently made to the Enterobacteriaceae, a family of human pathogens now spread across the Enterobacterales order. Important genera were placed in new families and important species were assigned to different genera. These changes will affect those who, for example, may no longer immediately recognize Klebsiella (formerly Enterobacter) aerogenes as a producer of a chromosomal AmpC beta-lactamase, which can directly impact the antibiotic selection and management of a patient with this infection (after all, there’s no "K" in "SPICE-HAM" or "SPACE," common acronyms used prior to the change). The visual below depicts the previous organization of the family and highlights the content and context of the recent changes using arrows. Consequently, these changes may be easier to retrieve, which is helpful when updating laboratory algorithms and interpreting results.
Bringing These Strategies Into Practice
New taxonomy, new techniques, new pathogens: microbiologists are true life-long learners, and experts in any field must continually update their knowledge. Visual tools can help novices and experts alike become better microbiologists, communicators and educators. Visual tools help both educators and learners of all stages to climb the Bloom’s Taxonomy pyramid by precisely addressing the traits that distinguish experts from novices: identifying patterns, organizing knowledge, cueing information when relevant and retrieving it fluently. Visuals can help instructors deliver the most effective learning tools, focusing on the high-yield takeaways that help novices strategically build understanding and expertise. Finally, while "creating" is the pinnacle of Bloom’s Taxonomy, creating visuals isn’t the only way to build knowledge. Many people and groups freely share their visuals, making this knowledge more accessible and transferable to the many careers in the field.
Where to Find Visual Tools for Clinical Microbiology
Finding effective learning tools has becoming increasingly important during the pandemic, when many learners (students, residents, fellows or life-long) have found both formal and casual learning settings harder to access. Several groups and approaches have effectively democratized these resources:
- Twitter: Resources shared on Twitter do not require an account to find or access them.
- My continually updated compilation of high-yield clinical microbiology visual tweets & tools.
- A pre-made feed from recommended Twitter accounts for Microbiology Bench Rounds, featuring dedicated educators like Clinical Microbiology Lab Director at Providence Sacred Heart Medical Center, Dr. Rich Davis.
- Excellent individual Twitter accounts to follow for microbiology visuals: @cullen_lilley, @LizzyHastie, @RichDavisPhD and @NMoore07.
- For clinical reasoning and medical education, follow @CPSolvers, @MedEdModels and @IDSAMedEdCOP (the medical education community of practice for the Infectious Diseases Society of America).
- Find new content by searching the hashtags #MicroMedEd, #MicroRounds, #IDTwitter and #MedEd.
- Massive open online courses (MOOCs): Sites like Coursera.org and FutureLearn.com have growing lists of free, high-quality microbiology courses.
- ‘Stories of Infection’ from Dr. Maya Adam, faculty at Stanford's Center for Health Education, uses a story-telling format to develop visual 1-pagers on important infections.
- Medical education websites:
- PathElective.com is a free resource with excellent modules on clinical bacteriology, mycology, virology and parasitology. It was created by Cullen Lilley and Dr. Kamran Mirza.
- To learn and continually practice clinical diagnostic reasoning skills (e.g., creating a differential diagnosis), the Clinical Problem Solvers (@CPSolvers) have dozens of visual tools on their website, linking to Twitter tutorials, schemas and more. As part of this team, Kara Lau (@ytk_lau) has created phenomenal "thought trains" to visualize key diagnostic problem-solving pathways, including important concepts such as abdominal pain and nausea and vomiting.
- GrepMed.com (“The Image Based Medical Reference”) is a tagged, searchable bank of images related to medicine. Searches for "microbiology" or "antibiotics" are a good place to get started.
- The Journal of General Internal Medicine’s Exercises in Clinical Reasoning include schemas & background on clinical diagnostic reasoning.