Let's Talk Micro

Metallo-β-lactamases (MBLs) have become an increasingly important topic in clinical microbiology and infectious diseases. While these enzymes were once encountered relatively infrequently in the United States, their epidemiology is changing, with NDM-producing organisms becoming more common. What makes metallo-β-lactamases different from other carbapenemases? Why are infections caused by MBL-producing organisms particularly challenging to treat? And what new treatment options are becoming available?

In this episode of Let's Talk Micro, Luis is joined by Dr. Ryan Shields and Dr. Emily Heil to discuss metallo-β-lactamases and their growing clinical significance. They explore the differences between serine β-lactamases and MBLs, review important enzymes such as NDM, VIM, and IMP, and discuss the challenges associated with treating infections caused by MBL-producing organisms. The conversation also covers emerging treatment options, including aztreonam-avibactam and cefepime-zidebactam, and highlights the importance of identifying specific carbapenemases to guide antimicrobial therapy.

Join us for a discussion on the evolving landscape of metallo-β-lactamases and the essential role of the clinical microbiology laboratory in patient care.

Guests:

• Ryan Shields, PharmD — University of Pittsburgh

• Emily Heil, PharmD — University of Maryland School of Pharmacy and University of Maryland Medical Center

Additional Reading:

McCreary EK, Heil EL, Aitken SL, et al. The global epidemiology and treatment of metallo-β-lactamase-producing gram-negative pathogens. JAC-Antimicrobial Resistance. 2026;8(5).

https://pubmed.ncbi.nlm.nih.gov/42876900/

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

When you open CLSI M100, what are you usually looking for? Susceptibility breakpoints? But did you know there's much more information available beyond susceptible, intermediate, and resistant interpretations?

In this episode of Micro Minutes, we explore useful information found throughout CLSI M100, including its tables, comments, and appendices. From intrinsic resistance and predicting susceptibility to other antimicrobials to understanding why certain agents should not be reported as susceptible, we highlight practical examples that can help clinical microbiology professionals interpret antimicrobial susceptibility results.

Whether you're a student or an experienced laboratory professional, join us as we take a closer look at CLSI M100 and discover what's beyond S, I, and R.

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Have you ever performed an organism identification using MALDI-TOF mass spectrometry and received a result showing multiple possible species, such as Enterobacter cloacae and Enterobacter asburiae, or Citrobacter freundii and Citrobacter werkmanii? Why does this happen? What do these organisms have in common, and why are they classified into groups or complexes?

In this episode of Micro Minutes, Luis explores bacterial groups and species complexes, why they exist, and how they relate to organism identification. He discusses several familiar and lesser-known examples, including the Enterobacter cloacae complex, Acinetobacter calcoaceticus–baumannii complex, Klebsiella pneumoniae species complex, Citrobacter freundii complex, and Pseudomonas putida group.

The episode also highlights the Burkholderia cepacia complex and why species-level identification can be particularly important in patients with cystic fibrosis.

Finally, learn why reporting an organism at the group or complex level is often appropriate, when additional identification may be necessary, and why understanding the capabilities and limitations of your identification system matters.

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

As artificial intelligence (AI) becomes increasingly integrated into biological research, the quality of the data used to develop these technologies is more important than ever. But what exactly is digital biology, and why does data quality matter?

In this episode of Let's Talk Micro, Luis is joined by Jonathan Jacobs, PhD, Senior Director of Bioinformatics at ATCC, to explore digital biology and the challenges associated with biological and genomic data. Dr. Jacobs discusses the importance of metadata, common issues with publicly available genomic databases, and why connecting digital information to authenticated biological materials is essential for reproducibility and reliable research.

The conversation also explores how data quality can affect AI models, the role of existing standards, and what researchers can do to improve the accuracy, completeness, and usefulness of the data they generate and share.

And, as always, stay until the end to hear Dr. Jacobs' favorite microorganism and what makes it so fascinating to him!

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Many microbiology professionals are familiar with ATCC strains used for quality control, validation, and verification—but what happens before those biological materials reach the laboratory? ATCC, the American Type Culture Collection, maintains biological materials used by scientists and laboratories around the world.

In this episode of Let's Talk Micro, Luis is joined by Dr. Shahin Ali, Senior Scientist at ATCC, to take a closer look at the work behind biological reference materials. Dr. Ali discusses how ATCC identifies and acquires microorganisms, what characteristics are considered when adding them to the collection, and how materials are authenticated, characterized, preserved, and maintained over time.

The conversation also explores expert curation and complete provenance, why authenticated reference materials are important for laboratory quality and reproducibility, and how individual strains of the same species can have meaningful differences. Luis and Dr. Ali also discuss antimicrobial resistance, the growing importance of genomic and metadata quality, and how curated biological collections may support AI-driven research in the future.

And, as always, stay until the end to hear Dr. Ali's favorite microorganism—and the personal connection behind his answer.

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Originally published on September 28, 2022, this episode returns to the Let's Talk Micro feed in recognition of World Rabies Day.

Dr. Rodney Rohde joins the podcast to discuss rabies and his extensive experience working with the virus in public health. We start with the basics: What is rabies? How is it transmitted? What are the signs and symptoms? From there, we discuss potential exposures, post-exposure prophylaxis, vaccination, and ways to prevent rabies. Dr. Rohde also shares his experience working in rabies diagnostics and molecular epidemiology, as well as his involvement with wildlife rabies vaccination efforts.

We also discuss the importance of recognizing potential exposures, the role of wildlife—particularly bats—and considerations when traveling to areas where rabies may be more prevalent.

Finally, what is World Rabies Day, and why is it observed on September 28? Dr. Rohde discusses the history and significance of the day and the importance of education, prevention, and collaboration in the fight against rabies.

Tune in as we revisit this conversation and learn more about rabies.

Resources

World Rabies Day: https://rabiesalliance.org/world-rabies-day

Dr. Rohde's rabies book: https://www.elsevier.com/books/rabies/wilson/978-0-323-63979-8

Dr. Rohde's website: https://rodneyerohde.wp.txstate.edu/

Related publication: https://pubmed.ncbi.nlm.nih.gov/33659941/

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

MAD-ID (Making a Difference in Infectious Diseases) and the Society of Infectious Diseases Pharmacists (SIDP) have joined forces to create a new annual meeting focused on antimicrobial therapeutics, stewardship, infectious diseases, and more.

In this episode of Let's Talk Micro, Luis is joined by Dr. Erin McCreary and Dr. Mike Rybak to discuss the history of MAD-ID and SIDP, what brought the two organizations together, and highlights from their 2026 meeting. They also discuss sessions relevant to clinical microbiology, practical approaches to applying new science, opportunities for networking and trainees, and what attendees can expect as the meeting moves forward under its new name: Antimicrobials Conference.

MAD-ID: https://www.mad-id.org/

Society of Infectious Diseases Pharmacists (SIDP): https://sidp.org/

Information on upcoming Antimicrobials Conference meetings: https://sidp.org/annualmeetings

Want to check out the Breakpoints podcast? https://breakpoints-sidp.org/

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Group A Streptococcus (GAS) is a common cause of pharyngitis, but deciding who should be tested and which testing method to use isn't always straightforward. In 2025, the Infectious Diseases Society of America (IDSA) released updated guidelines on Group A streptococcal pharyngitis, bringing renewed attention to diagnostic stewardship and the use of clinical scoring systems to help guide testing decisions.

In this episode of Let's Talk Micro, Dr. Christopher Doern returns to the podcast to break down the updated IDSA guidelines and what they may mean for clinical practice. We discuss clinical scoring systems such as Centor and McIsaac, antigen testing, culture, molecular diagnostics, and point-of-care testing. We also explore turnaround time and cost considerations, GAS carriage and the interpretation of positive results, and how diagnostic decisions connect with antimicrobial stewardship.

Tune in as we take a practical look at what's changing in Group A strep testing and how laboratories and clinicians can approach these updated recommendations.

This podcast episode is sponsored by Cepheid. The views and opinions expressed by the interviewer in this interview are their own and do not necessarily reflect the position of Cepheid.

IDSA Clinical Practice Guideline Update on Group A Streptococcal (GAS) Pharyngitis: IDSA 2025 Group A Streptococcal Pharyngitis Guideline

Current Laboratory and Point-of-Care Pharyngitis Diagnostic Testing and Knowledge Gaps: https://pubmed.ncbi.nlm.nih.gov/39688598/

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Artificial intelligence is changing how healthcare professionals access and use clinical information. But what does that look like at the point of care?

In this episode of Let's Talk Micro, Luis is joined by Dr. Declan Kelly, physician, software engineer, and founder of Eolas Medical, to discuss the role of AI in clinical decision support. Dr. Kelly shares how challenges accessing institutional guidelines and clinical knowledge led to the development of Eolas Medical and how AI can help healthcare professionals find the information they need when making clinical decisions.

The conversation explores the importance of local guidelines, the connection between the clinical microbiology laboratory and antimicrobial stewardship, and how AI can help bridge the gap between laboratory data, institutional knowledge, and patient care. They also discuss evidence supporting these technologies, concerns surrounding AI hallucinations and clinical safety, and how clinical decision support may evolve in the years ahead.

Tune in to learn how AI is changing the way clinical knowledge is accessed and what that could mean for the future of healthcare.

This episode is brought to you in collaboration with Eolas Medical.

Eolas Medical is a clinical knowledge platform founded by physician Dr. Declan Kelly, who saw firsthand how hard it can be to find trusted guidance at the point of care. Using AI grounded exclusively in an organization's own approved protocols and guidelines, Eolas gives clinicians fast, accurate answers instead of generic search results. It is used across 90% of acute NHS trusts and 600+ sites globally, including Stanford and Mass General Brigham. For antimicrobial stewardship, a peer-reviewed study published in Nature Portfolio's npj Antimicrobials and Resistance found prescribing accuracy improved from 47% to 100% with Ask Eolas at the point of care.

Resources

Eolas Medical: https://www.eolasmedical.com/

Study — Enhancing quality of antimicrobial prescribing through 'Ask Eolas' (language model): a user-testing and simulation evaluation: https://www.nature.com/articles/s44259-026-00187-7

Summary of study: Eolas Medical — Summary of the study and implications for antimicrobial stewardship

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi

Let's Talk Micro is back for a new season! In this season premiere, Luis is joined by Dr. Megan Amerson-Brown to discuss the important connection between clinical microbiology and infection prevention.

Dr. Amerson-Brown shares her career journey from the microbiology bench to infection prevention and ultimately laboratory leadership. She discusses how microbiologists contribute to infection prevention through surveillance, diagnostic stewardship, outbreak investigations, and collaboration with infection prevention teams.

The conversation also explores how laboratorians can become more involved in infection prevention while remaining in the laboratory, resources and certifications for those interested in the field, the importance of mentorship, and potential career pathways for microbiologists considering a transition into infection prevention.

Tune in to the season premiere and learn more about the role microbiologists play in infection prevention and the opportunities available both at and beyond the bench.

• a-IPC™ (Associate – Infection Prevention and Control) Examination — Information about the entry-level infection prevention and control certification discussed during the episode.

• CIC® (Certification in Infection Control and Epidemiology) Examination — Information about the CIC certification examination.

• APIC – Association for Professionals in Infection Control and Epidemiology — Education, career development, and other resources for infection prevention professionals.

Stay connected with Let's Talk Micro:

• Website: letstalkmicro.com

• Questions or feedback? Email me at [email protected]

• Interested in being a guest on Let's Talk Micro? Fill out the form here: https://forms.gle/V2fT3asjfyusmqyi8

Support the podcast:

• Venmo

• Buy me a Ko-fi