Antimicrobial Testing–Are We Doing it Wrong?

Antibiotic resistance is a huge concern for microbiologists. In addition to stewardship programs and regulating agricultural use of antibiotics, is it time to re-examine clinical testing paradigms?

A recent study suggests that the typical way microbiologists test for antibiotic susceptibility–meuller-hinton plates and antibiotic disks–might be fallible. When his team tested Salmonella against polymyxin using typical methods, the organism tested sensitive; when the tested the same organism against the same antibiotic using medium that more closely resembled human cells, the organism tested resistant.

Bloomberg Business discusses the paper here. The article is worth your time, even if the info-graphic gives erroneous information (it mentions meuller-hinton broth instead of meuller-hinton agar plates).

An Interactive Tool to See Antibacterial Resistance Over Time

Do you need to know the percentage of Salmonella Typhi resistant to nalidixic acid in California in 2001? A resource now exists that can give you that answer.

The Centers for Disease Control (CDC) has released a tool called National Antimicrobial Resistance Monitoring System (NARMS) Now: Human Data, and it allows users to access antimicrobial resistance data based on year and geographical region. The interactive site tracks resistance for four bacteria that cause foodborne illness: Salmonella, Shigella, Campylobacter, and E. coli O157.

Using Evolution to Thwart Resistance

The very act of using antibiotics contributes to antibiotic resistance. Bacteria are exposed to an antimicrobial agent and develop genetic strategies to survive repeated exposures. But what if using antibiotics in a certain sequence could revert resistant strains to the wild type? Researchers from California and Washington DC tested that theory and discovered some promising results.

You can read the PLOS ONE study and the Scientific American article to learn more.

NIH Funds Antimicrobial Resistance Diagnostics Projects

As I mentioned in a previous post, diagnostic uncertainty drives antibiotic use, so getting answers to clinicians faster is an important piece of the antimicrobial stewardship pie. NIH is stepping up and funding several efforts around the country. From the press release:

“The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, has awarded more than $11 million in first-year funding for nine research projects supporting enhanced diagnostics to rapidly detect antimicrobial-resistant bacteria.”

The funded researchers include a mix of companies and academic centers including BioFire Diagnostics, LLC and Brigham Young University in Provo, Utah.

Read the full press release here.

 

Swails

Kelly Swails, MT(ASCP), is a laboratory professional, recovering microbiologist, and web editor for Lab Medicine.

 

 

The Future Cost of Antimicrobial Resistance

Over on Superbug, Maryn McKenna (are you following her yet? No? If you’re into infectious disease, you should) discusses a recent report on the global ramifications of antimicrobial resistance. In it, the authors project by 2050, 10 million deaths a year will be attributed to infections caused by six resistant organisms. (Those are: Klebsiella pneumoniae, E. coli, MRSA; HIV, TB and malaria.) These deaths will cause an estimated loss of 100 trillion dollars of lost gross national product.

So what can laboratory professionals and pathologists do to help stop these predictions from coming true? For starters:

  • Advocate for and implement antibiotic stewardship programs.
  • Educate the public about proper antibiotic use.
  • Practice good laboratory safety practices.

What else can labs, microbiologists, and pathologists do to stem the tide of antibiotic resistance?

Swails

Kelly Swails, MT(ASCP), is a laboratory professional, recovering microbiologist, and web editor for Lab Medicine.