Klebsiella pneumoniae

Is K. pneumoniae gram - or gram +?

It is gram -

What shape is K. pneumoniae?

encapsulated rod

Is K. pneumoniae motile or non motile?

Non-motile

Is K. pneumoniae and anaerobe or aerobe?

It is a facultative anaerobe

Is K. pneumoniae oppurtunistic?

Yes, it is an opportunistic pathogen.

What does CRE stand for?

Carbapenem resistant Enterobacteriaceae

What group of highly resistant bacteria is K. pneumoniae in?

CRE (carbapenem resistant enterobacteriaceae)

What do bacteria that are carbapenem resistant have?

They have ESBLs (Extended spectrum beta-lactamase enzymes) which cleave penicillins and can be treated with carbapenem however, bacteria resistant to carbapenem cannot be treated with it. This makes K. pneumoniae virtually untreatable.

What are ESBLs?

Extended spectrum beta-lactamase enzymes which cleane penicillins and require carbapenem antibiotic to treat.

What is Klebsiella pneumoniae reservoir?

Mouth, skin, GI tract of humans and animals, soil, water, food

How is K. pneumoniae transmitted?

oral-fecal; direct contact; person to person (feces)

How is K. pneumoniae NOT transmitted?

It is not transmitted through the air.

What are some specific scenarios where K. pneumoniae can be transmitted?

• contaminated hands (healthcare personnel)

• medical devices (catheter/ ventilator)

• enter wounds (injury/ surgery)

What diseases does K. pneumoniae cause?

• Pneumonia

• UTI

• Sepsis

What are the main symptoms of pneumonia?

Fever, cough, chest pain, difficulty breathing

What are the main symptoms of a UTI?

pain during urination, cloudy or bloody urine

What could increase your risk of getting pneumonia from a K. pneumoniae infection?

ventilators

What could increase your risk of getting a UTI from a K. pneumoniae infection?

urinary catheters

What could increase your risk of getting sepsis from a K. pneumoniae infection?

IV catheters (sepsis is in blood)

Can long term or short term antibiotics increase your risk of a K. pneumoniae infection?

Yes, long-term Abx increases your chance of getting infected.

What are the general steps of pathogenesis for K. pneumoniae (causing pneumonia)?

• colonization of oropharynx (middle part of throat behind mouth)

• inhalation into lung, growth and proliferation

• production of biofilms

• onset of pneumoniae; bacteremia (bacteria in blood)/ sepsis

What are the virulence factors of K. pneumoniae?

• polysaccharide capsule (>80 serotypes like Sreptococcus pneumoniae)

• pili: adherence to host tissues: biofilm formation in bladder and abiotic surfaces (medical devices)

• siderophores: iron-scavenging proteins, allows bact. to steal iron from host protein (iron is essential for bacteria growth)

• colibactin: cytotoxin: gut colonization/ mucosal invasion

  • crosslinks host DNA causing double-strand breaks, leads to cell cycle arrest and cell death (cytotoxic/ mutational)

How do biofilms help bacteria survive?

By protecting them from antibiotics and host immune defenses.

What two bacteria are colibactin mainly associated with?

E. coli and Klebsiella pneumoniae

What is hypervirulent Klebsiella pneumoniae (hvKP)?

It is a distinct pathotype from regular KP. While KP is an opportunistic pathogen that causes disease in at-risk individuals, hvKP can cause severe and invasive infections in healthy individuals.

What is KP diagnosis based on?

Diagnosis is based on location of infection/ symptoms.

What is the main treatment for KP? What is the biggest challenge?

The main treatment is Abx, the problem is carbapenem resistance.

How can KP be prevented?

Strict hygiene by healthcare personnel.