Klebsiella pneumoniae
One-Sentence Definition
Klebsiella pneumoniae is a Gram-negative, usually heavily encapsulated Enterobacterales rod causing pneumonia, UTI, and invasive disease — notorious for carbapenemase-producing MDR clones.
Taxonomy & Morphology
- Gram-negative bacillus; lactose fermenter; non-motile
- Mucoid colonies from prominent Capsule
- Gram Stain: pink rods ± capsule halo impression
Virulence Highlights
- Capsule (hypervirulent strains: liver abscess, metastatic spread)
- Siderophores; LPS
- Hospital adaptation + plasmid AMR
Clinical Syndromes
- HAP/VAP, UTI, bacteremia, wound infection
- Hypervirulent pathotype: community liver abscess (esp. in Asia; increasingly global)
Diagnosis
- Culture + ID (MALDI/biochemicals)
- AST critical; molecular carbapenemase detection where available
- WGS for outbreak tracing
Treatment Notes (conceptual)
- Directed by AST; carbapenem-resistant isolates need specialist regimens (ceftazidime-avibactam, etc. — region-specific)
- Source control for abscesses
AMR
- ESBL common; CRE with KPC, NDM, OXA-48-like enzymes — typically Plasmid / Conjugation
- Core organism for MOC - Antimicrobial Resistance (AMR) and Paper - AMR Database M.Centner 2026
Related Notes
- Escherichia coli · Capsule · Whole-Genome Sequencing
- MOCs: MOC - Bacteriology · MOC - Clinical Microbiology · MOC - Antimicrobial Resistance (AMR)
Active Recall
- What colony clue suggests a heavy capsule?
- Name two carbapenemase families seen in Klebsiella.
- Hypervirulent vs classical MDR Klebsiella — clinical difference?