Implications of accurate pseudomonad identification for patient care, antimicrobial stewardship, and outbreak investigations

Abstract

In low-resource clinical microbiology laboratories, the identification of non- fermenting, oxidase-positive Gram-negative bacilli remains a significant challenge. Due to limited diagnostic capabilities, there is a pervasive tendency to report all such organisms simply as Pseudomonasspecies, often implicitly considered Pseudomonas aeruginosa. This practice overlooks the vast diversity within the Pseudomonadaceae family, which includes numerous genera such as Burkholderia, Stenotrophomonas, Achromobacter, Ochrobactrum, Ralstonia, and many non-aeruginosa Pseudomonas spp. This misidentification poses serious clinical consequences, as intrinsic antibiotic resistance profiles vary dramatically across these species, leading to inappropriate therapy and treatment failure. Furthermore, it curtails effective epidemiological surveillance and source investigation during outbreaks. This paper delineates the scope of this problem, its impact on patient care and public health, and proposes a multifaceted, feasible way forward for laboratories constrained by resources. With this, the author calls for the adoption of stratified, algorithmic approaches using basic biochemical tests and enhanced training, as well as the strategic development of affordable, context-specific diagnostic solutions.

Keywords

Pseudomonads / Gram-negative bacilli / Antimicrobial resistance / Outbreak investigation / Diagnostic stewardship / Antimicrobial stewardship / Clinical microbiology / Low-resource settings

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