Half of all hospital patients receive at least one antibiotic, and up to 50% of these may be

inappropriately prescribed.^1,2
 

To successfully manage bacterial infections and further our fight against resistance, prompt and accurate identification of the responsible pathogen is key.^3,4 Coordinated efforts, in line with the principles of stewardship, will help in our quest for judicious antibiotic use.⁵
 

Read more about actions we can take against antibiotic resistance (ABR).


 

WHO SAYS HOW
 

In 2019, the WHO’s (World Health Organization) report on diagnostic defenses against

antibacterial resistance, highlighted unmet needs and priorities for the future.⁵

Current ways to identify bacterial infections include:⁵

• Phenotypic identification : e.g. bacterial cultivation, microscopy, etc.
• Immunoassay
• Molecular methods : e.g. hybridization or amplification
• Sequencing

WHO also outlines new tools that are required to fill diagnostic gaps:⁵

• Rapid tests that distinguish between bacterial and viral infections
• New tests for pathogen identification
• New tests for antimicrobial susceptibility patterns

NO STAIN, NO GAIN?

Of the available approaches, the Gram stain has remained the most frequently used rapid

diagnostic test for differentiating bacterial infections for over a century. The stain divides

bacteria into two groups – Gram-negative and Gram-positive - based on their cell wall and

membrane permeability to organic solvents.³
 

Yet, cell culture followed by evaluation to identify particular strains and species, is the gold standard. This method is cost-effective and usually has specificity but is limited by long

turnaround times and can lack sensitivity. Modern mass spectrometry methods can reduce the time needed for identification (from hours to several minutes), but often still require bacterial cultivation as a first step.⁴
 

Read about newer approaches for diagnosing different types of bacterial infections below.

The urgent threat of antibacterial resistance means we need appropriate tools and

prescribing. Existing diagnostics are a start, but we must ensure they are used diligently to

identify targeted treatment in our fight against this ever-evolving global health threat.