Table 2.
Key virulence markers among various pathotypes of Kp.
| Classical Kp (cKp) | Hypermucoviscous Kp (hmKp) | Hypervirulent (hvKp) susceptible Kp | Hypermucoviscous hypervirulent susceptible Kp | Hypervirulent multidrug-resistant Kp | |
|---|---|---|---|---|---|
| String test | − | + | +/− | + | − |
| Virulence plasmid | − | +/− | + | + | + |
| Mosaic plasmid | − | − | − | − | + |
| Wild-type rmpA | − | v | + (100%) | + (100%) |
|
| Wild-type rmpA2 | − | v | + (100%) | + (100%) | − |
| Mutated rmpA2 | − | − | − | − | + (100%) |
| Aerobactin | − | − | + (100%) | + (100%) | + (100%) |
| Salmochelin | − | − | +/− (80%) | +/− (80%) | +/− (<10%) |
| Peg-344 | − | − | + (v) | + (v) | +/− (v) |
| Phenotypic identification | Identified | Identified | Identified | Identified | unidentified |
| Genotypic identification | Not essential to designate as cKp | Not essential to designate as hmKp | Mandatory to identify as hvKp | Mandatory to identify as hvKp | Mandatory to identify as hvKp |
| Correlation with clinical features | Not essential to designate as cKp | Not essential to designate as hmKp | Mandatory to identify as hvKp | Mandatory to identify as hvKp | Mandatory to identify as hvKp |
| Clones | Diverse | Diverse | CC23, CC65 | CC23, CC65 | Regional, driven by resistance profile |
| Clinical impact | Less pathogenic; good clinical outcome; Treatment with antibiotics | Challenges antimicrobial penetration though less virulent | Fatal outcome though susceptible Good biofilm formers | Fatal outcome; poor antibiotic penetration Good biofilm formers | Fatal outcome |
Kp, Klebsiella pneumoniae; V, variable; CC, clonal complex.