Hospital-Acquired
Pneumonia
Internal Medicine Mini-Lecture
Revised Jan 2016
Learning Objectives
• Definition of Hospital-Acquired Pneumonia (HAP).
• Risk factors associated with HAP.
• Current treatment guidelines
Clinical Case
68-yo female with insulin-dependent diabetes presents with 2day history of fever, cough, and pleuritic chest pain. She had
knee replacement surgery 60 days ago and spent 2 weeks at a
rehabilitation facility.
On exam, temp 101.8 F, HR 124, BP 110/76, RR 24 with O2 sat
92% on RA. She is alert and oriented with NAD. Auscultation
reveals RLL crackles. White count 18,000 with L shift, BUN 32.
CXR shows focal consolidation in RLL.
What antimicrobial treatment should be initiated?
Definitions
Hospital-acquired pneumonia, HAP
Pneumonia occurring more than 48 hours after
admission, not present at admission.
Ventilator-associated pneumonia, VAP
Pneumonia developing 48 hours after
endotracheal intubation.
Definitions
Healthcare-associated pneumonia, HCAP
Pneumonia that occurs in a patient with extensive
healthcare contact, one or more of the following:
• IV therapy, wound care, or IV chemotherapy within the
prior 30 days.
• Residence in a nursing home or long-term care facility
• Hospitalization in an acute care hospital for two or
more days within the prior 90 days
• Attendance at a dialysis clinic within the prior 30 days
Risk Factors for HAP
Modifiable
Non-modifiable
Depressed level of consciousness
Age > 70 years
Enteral nutrition
Immunosuppression
Malnutrition
Thoracic or abdominal surgery
Mechanical ventilation
Underlying chronic lung disease
Oropharyngeal colonization
Re-intubation
Stress ulcer prophylaxis
Supine position
Treatment
Empiric treatment guidelines depend on whether HAP is early or
late onset (>4 days) and risk factors for MDR pathogens present.
Risk Factors for Multi-Drug Resistant pathogens
• Antimicrobial therapy in preceding 90 days
• Onset of pneumonia after 5 days of hospitalization
• High frequency of antibiotic resistance in the community or
hospital unit
• Duration of ICU stay and mechanical ventilation
• Immunocompromised state
American Thoracic Society, Infectious Diseases Society of America. Guidelines for the
management of adults with hospital-acquired, ventilator-associated, and healthcareassociated pneumonia. Am J Respir Crit Care Med 2005; 171:388.
Treatment
For early onset with no MDR risk factors:
• Pathogens include S. pneumo, H. influenzae, MSSA, E. coli,
Enterobacter, Proteus.
• Recommended antibiotics: Ceftriaxone or Levofloxacin or
Unasyn or Ertapenem.
Source: American Thoracic Society, Infectious Diseases Society of America. Guidelines for the
management of adults with hospital-acquired, ventilator-associated, and healthcare-associated
pneumonia. Am J Respir Crit Care Med 2005; 171:388.
Treatment
For late onset or MDR risk factors present:
• Pathogens include Pseudomonas, Klebsiella ESBL,
Acinetobactor, MRSA, Legionella.
• Recommended antibiotics: Cefepime or imipenem or Zosyn
PLUS levofloxacin or gentamicin PLUS vancomycin or linezolid
Source: American Thoracic Society, Infectious Diseases Society of America. Guidelines for the
management of adults with hospital-acquired, ventilator-associated, and healthcare-associated
pneumonia. Am J Respir Crit Care Med 2005; 171:388.
Special considerations
No evidence indicates that HAP or VAP caused by Pseudomonas
species requires combination therapy or that a synergistic
combination improves outcomes.
Oral anaerobe coverage may be considered for patients with a
witnessed aspiration event or recent surgery.
All patients should be re-evaluated for clinical improvement and
review of microbiologic results at 48 to 72 hours and considered
for de-escalation (narrow spectrum or oral therapy).
Special considerations
The duration of therapy for HAP and VAP is generally 7 to 8 days
except in cases caused by Pseudomonas or Acinetobacter spp.,
for which treatment should continue for 14 days.
Patients who do not improve within 72 hours of appropriate
antimicrobial therapy should be evaluated for infectious
complications (e.g. empyema or lung abscess), an alternate
diagnosis (e.g. PE, ARDS, neoplasm), or another site of infection
(e.g. C. diff colitis, pleural effusion) to explain the clinical picture.
Clinical Case
68-yo female with insulin-dependent diabetes presents with 2day history of fever, cough, and pleuritic chest pain. She had
knee replacement surgery 60 days ago and spent 2 weeks at a
rehabilitation facility.
On exam, temp 101.8 F, HR 124, BP 110/76, RR 24 with O2 sat
92% on RA. She is alert and oriented with NAD. Auscultation
reveals RLL crackles. White count 18,000 with L shift, BUN 32.
CXR shows focal consolidation in RLL.
What antimicrobial treatment should be initiated?
Clinical Case
Patient was started on Cefepime, Levofloxacin, and Vancomycin
for HCAP with MDR risk factors. She is at risk for MDR pathogens
due to her history of diabetes and recent knee surgery with
subsequent rehab.
On hospital day 3, sputum culture grew MRSA. Cefepime and
Levofloxacin stopped. After a 10-day course of Vancomycin,
patient improved and was sent home.
Summary
• Prompt, appropriate, broad-spectrum antimicrobial therapy
should be started for all patients with suspected HAP.
• Patients with HCAP need therapy for MDR pathogens.
• De-escalation of antibiotics should be considered once the
results of culture and patient’s clinical response are known.
• Nonresponding patient should be evaluated for possible MDR
pathogens, extrapulmonary sites of infection, and
noninfectious causes.
References
• American Thoracic Society, Infectious Disease Society of
America. Guidelines for the management of adults with
hospital-acquired, ventilator-associated, and healthcareassociated pneumonia. Am J Respir Crit Care Med 2005;
171:388.
• American College of Physicians. MKSAP 17: Infectious
Disease. 2015: 82-84.
MKSAP question
59-yo man is evaluated in the ICU for fever and leukocytosis. He
was admitted 13 days ago with respiratory failure resulting from
Guillain-Barre syndrome. He was intubated and mechanically
ventilated.
On hospital day 9, he developed fever without an increase in
secretions or change in oxygenation. A new left lower lobe
infiltrate was seen on chest X-ray, and his leukocyte count was
17,500. Sputum culture grew MSSA. Nafcillin was started.
Medical history is otherwise unremarkable. Medications are
nafcillin and IVIG.
MKSAP question
On exam, temp is 100.8 deg F, blood pressure is 132/84 mm Hg,
pulse is 94/min, and respiratory rate is 18/ min. Lung exam
reveals decreased breath sounds in the left lower lung field.
Lab studies show a leukocyte count of 17,300. Sputum gram
stain reveals 1+ leukocytes and 1+ gram-positive cocci in
clusters. Remainder of the exam is noncontributory.
A new moderate left pleural effusion is seen on chest X-ray, but
no increase in the LLL infiltrate. CT scan shows LLL consolidation
with air bronchograms and a moderate left pleural effusion.
MKSAP question
Which of the following is the most appropriate next step in
management?
(A)
(B)
(C)
(D)
Add gram-negative antimicrobial coverage
Change nafcillin to vancomycin
Perform bronchoscopy with bronchoalveolar lavage
Perform thoracentesis
MKSAP answer
Answer: (D) perform thoracentesis
This patient should undergo thoracentesis to determine why he
is not improving with treatment. In patients who do not respond
to appropriate treatment after 72 hours, it is imperative to
search for another explanation (such as infectious compication,
another site of infection, or an alternate diagnosis). A new or
increasing pleural effusion could represent a parapneumonic
effusion, empyema, or a lung abscess. Thoracentesis and pleural
fluid examination should be performed because the results
could significantly alter management.