Internal Medicine · Year 3 · from Internal Medicine
Case 2: Hospital-Acquired Pneumonia
Patient Presentation
A 72-year-old woman developed fever and increased oxygen requirements on hospital day 5. She was admitted for hip fracture repair and has been mobilizing slowly due to pain. She has a history of diabetes and chronic kidney disease. She has been receiving DVT prophylaxis and has a peripheral IV.
Vital Signs
- Blood Pressure: 108/62 mmHg
- Heart Rate: 105 bpm
- Respiratory Rate: 26/min
- Oxygen Saturation: 88% on 4L NC (was 96% on room air yesterday)
- Temperature: 39.1°C
Physical Examination
- General: Appears ill, somewhat confused
- Pulmonary: Decreased breath sounds at right base, coarse crackles
- Cardiovascular: Tachycardic
- Skin: Surgical incision clean
Laboratory and Imaging
- WBC: 18,500/μL with 15% bands
- Creatinine: 2.1 mg/dL (baseline 1.5)
- Chest X-ray: New right lower lobe infiltrate
- Blood cultures: Pending
- Sputum culture: Pending (purulent sputum obtained)
Clinical Image
Figure 2: Chest X-ray showing new right lower lobe infiltrate developing in a hospitalized patient, consistent with hospital-acquired pneumonia.
Image Source: Educational illustration for teaching purposes.
Questions
- What defines hospital-acquired pneumonia (HAP)?
- A) Any pneumonia in a hospitalized patient
- B) Pneumonia occurring ≥48 hours after hospital admission, not incubating at admission
- C) Pneumonia in a patient with recent hospitalization
- D) Pneumonia requiring ICU care
- What are the most common pathogens in HAP?
- A) Streptococcus pneumoniae and Haemophilus influenzae
- B) MRSA, Pseudomonas aeruginosa, and other gram-negative bacilli
- C) Mycoplasma and Legionella
- D) Influenza virus
- What is the appropriate empiric antibiotic regimen for HAP?
- A) Azithromycin alone
- B) Antipseudomonal beta-lactam; add MRSA coverage if risk factors present
- C) Fluoroquinolone alone
- D) Ampicillin-sulbactam
- What are risk factors for multidrug-resistant (MDR) pathogens in HAP?
- How does VAP differ from HAP in definition and management?
Answers
- B) Pneumonia occurring ≥48 hours after hospital admission, not incubating at admission - HAP is defined as pneumonia that develops ≥48 hours after hospital admission and was not incubating at the time of admission. This distinguishes it from CAP that becomes apparent after admission.
- B) MRSA, Pseudomonas aeruginosa, and other gram-negative bacilli - HAP pathogens differ from CAP:
- Pseudomonas aeruginosa
- MRSA
- Klebsiella, Acinetobacter, Enterobacter
- S. pneumoniae is less common in HAP
- B) Antipseudomonal beta-lactam; add MRSA coverage if risk factors present - Empiric therapy:
- Antipseudomonal beta-lactam (piperacillin-tazobactam, cefepime, or meropenem)
- Add vancomycin or linezolid if MRSA risk factors present
- Add second gram-negative agent if high risk for MDR or high mortality risk
- Risk factors for MDR pathogens:
- Prior IV antibiotic use within 90 days
- Hospitalization >5 days before HAP onset
- Prior MRSA infection or colonization
- Structural lung disease (bronchiectasis, COPD)
- High local prevalence of MRSA or resistant gram-negatives (>10-20%)
- Septic shock
- ARDS before HAP
- Acute renal replacement therapy
- Recent hospitalization (within 90 days)
- VAP vs. HAP:
- VAP definition: Pneumonia developing >48 hours after endotracheal intubation
- VAP pathogens: Similar to HAP but higher rates of Pseudomonas and Acinetobacter
- VAP prevention: HOB elevation, daily sedation interruption, oral chlorhexidine, early mobilization, VAP bundles
- VAP diagnosis: Can be challenging; clinical pulmonary infection score (CPIS) may help
- Management: Similar empiric coverage; strongly consider MDR coverage