Patient-specific drug-resistant bacterial pathogen

A patient-specific drug-resistant bacterial pathogen refers to a clinical isolate of bacteria from an individual patient that exhibits resistance to one or more antimicrobial agents (World Health Organization [WHO], 2023). This term describes a whole organism—such as a specific strain of Methicillin-resistant Staphylococcus aureus (MRSA) or Carbapenem-resistant Enterobacteriaceae (CRE)—rather than a single molecular target like a receptor or enzyme (Centers for Disease Control and Prevention [CDC], 2021). These pathogens are the focus of personalized medicine, where treatments like phage therapy or tailored antibiotic combinations are selected based on the isolate's unique resistance profile (Nature Reviews Microbiology, 2017). Drugs interact with these pathogens by targeting essential bacterial components, such as the cell wall, ribosomes, or DNA gyrase, to inhibit growth or cause cell death (National Institutes of Health [NIH], 2022). Because the term refers to a broad category of organisms and not a specific molecule, it is considered an incorrect or non-specific target in molecular pharmacology. Effective management requires rapid diagnostic identification of resistance markers to guide the use of last-resort therapies (Journal of Clinical Microbiology, 2019). The emergence of these pathogens is driven by selective pressure from antibiotic use and horizontal gene transfer of resistance determinants. Therapeutic challenges include the risk of systemic toxicity from potent antibiotics and the potential for the pathogen to evolve further resistance during treatment.

Other names

Multidrug-resistant organismMDROClinical isolatePatient-derived bacterial strainSuperbugDrug-resistant isolate

Antimicrobial agents target various bacterial processes including cell wall synthesis, protein synthesis (30S or 50S ribosomal subunits), nucleic acid replication, and metabolic pathways to inhibit growth or induce cell death.