Related Subjects: Asthma
|Acute Severe Asthma
|Exacerbation of COPD
|Pulmonary Embolism
|Cardiogenic Pulmonary Oedema
|Pneumothorax
|Tension Pneumothorax
|Respiratory (Chest) infections Pneumonia
|Fat embolism
|Hyperventilation Syndrome
|ARDS
|Respiratory Failure
|Diabetic Ketoacidosis
⚠️ Klebsiella pneumoniae is a major cause of hospital-acquired pneumonia. Rising antibiotic resistance, including carbapenem resistance, makes it a critical healthcare challenge.
📖 About
- Originally called Friedländer's bacillus, part of the Enterobacteriaceae family.
- Lactose-fermenting Gram-negative bacillus 🦠.
- Large polysaccharide capsule is the main virulence factor → protects against phagocytosis and immune clearance.
- Capsule-deficient strains are far less virulent.
🌍 Source
- Normal flora in the GI tract and oropharynx.
- Opportunistic pathogen in hospitals → respiratory & urinary tract infections.
- High virulence and resistance → major concern in nosocomial outbreaks.
🔬 Characteristics
- Gram-negative, encapsulated rods.
- Aerobic / facultative anaerobe.
- Ferments glucose & lactose → pink colonies on MacConkey agar 🎨.
- Oxidase-negative, catalase-positive, reduces nitrates to nitrites.
🩺 Clinical Presentation
- Respiratory: Severe lobar pneumonia, currant jelly sputum (thick, bloody), dyspnoea, fever, sepsis.
- High-risk groups: 🍺 alcoholics, 🩸 diabetics, ventilated patients, chronic lung disease.
- May show bulging fissure sign on CXR (due to lobar expansion).
⚠️ Pathogenicity
- Pneumonia: Classically affects debilitated or alcoholic patients → necrotising, cavitating infection.
- UTIs: Associated with long-term catheterisation or diabetes.
- Pyogenic Liver Abscess: Invasive syndrome with bacteremia, especially in diabetics or immunocompromised.
🧪 Resistance
- ESBLs: Extended-spectrum beta-lactamases → resistant to many penicillins & cephalosporins.
- Carbapenem resistance: Carbapenemase-producing strains (KPC, NDM) → highly resistant, limited options.
- Multidrug resistance to fluoroquinolones, aminoglycosides, etc. is increasingly common.
💊 Management
- Supportive care: Oxygen, airway management, chest physiotherapy, HDU/ICU support if severe.
- Antibiotics: Guided by microbiology & sensitivity results:
- Non-resistant strains → 3rd-gen cephalosporins (ceftriaxone), fluoroquinolones, aminoglycosides.
- ESBL-producing strains → carbapenems (meropenem, imipenem) 🚑.
- Carbapenem-resistant strains → combination regimens: colistin, tigecycline, fosfomycin, ± ceftazidime-avibactam.
- Prognosis: Mortality remains high (30–50%), especially in elderly, diabetic, or immunosuppressed patients.
