Nosocomial Pneumonia Flashcards
Types of nosocomial pneumonias
- HAP (hospital-acquired pneumonia)
- VAP (ventilatory assoc. pneumonia)
- HCAP (Health care assoc. pneumonia)
HAP
develops more than 48 hours after admission to the hospital
VAP
Development of pneumonia in a mechanically ventilated pt 48 hours after enrtracheal intubation
HCAP
development of pneumonia in an outpt setting in an individual with extensive health care contact -> ex: dialysis
What is so scary about nosocomial pneumonia?
mortality: 20-50%
second most common cause of infection among hospitalized patients (behind UTIs)
Risk factors for HCAP
- abx in last 3 months
- hosp. in last 3 months of at least 2 days duration
- resident of a nursing home or extended care facility
- home infusion therapy within the last month
- long term dialysis
- home wound care
- family member with an infection involving a multiple drug resistant pathogen
- immunosuppression (disease or therapy)
What makes nosocomial pneumonia different from CAP?
- change in normal flora: flora develops different resistant patterns
- different pathogens
- High frequency of drug resistance
- patients have worse underlying health status
pathophysiology of nosocomial pneumonia
- colonization of the stomach and the pharynx : on NG tubes or ventilators
- within 48 hours of admission 75% of seriously ill patients will have upper airway colonization with organisms from the hospital
Organisms associated with nosocomial pneumonia?
- strep pneumo: often drug resistant
- staph aureus: MSSA and MRSA
- gram - rods: non-ESBL, ESBL: Klebsiella pneumonia, E. coli, Enterobacter
- pseudomonas aeruginosa
- Acinetobacter species
organisms associated with HAP?
- staph aureus
- Pseudomonas aeruginosa
- gram - rods: enterobacter, Klebsiella pneumonia, E. coli
organisms associated with VAP?
- MRSA 18%
- P. aeruginosa 18%
- MSSA 9%
- stenotrophomonas maltophilia 7%
- Acinetobactor sp 8%
- other spp: 9%
HCAP associated organisms
- all the common organisms that are more likely to be drug resistant
Signs and symptoms of nosocomial pneumonia
- same as with community acquired pneumonia but more severe
- appear acutely ill
- fever
- may have hypothermia (elderly)
- tachypnea
- tachycardia
- decreasd SpO2
- rales/crackles (inspiratory )
- bronchial breath sounds
- dullness to percussion
Diagnostic clues to nosocomial pneumonia?
- strep pneumoniae: rust colored sputum
- pseudomonas, Haemophilus and pneumococcal species: may produce green sputum
- Klebsiella species pneumonia: red currant-jelly sputum
- anaerobic infections: often produce foul-smelling or bad tasting sputum
RFs and features of Klebsiella pneumonia?
RFs: elderly, alcoholics, debilitated hospital pts
Features: gram - member of Enerobacteriacae, can cause extensive pulmonary necrosis, cavitations (holes) seen on X-ray, abscess formation (empyema), pleural adhesions
- potentially fatal, up to 5% of pneumonia cases may be Klebsiella
Presentation of Klebsiella pneumonia
- rapid onset of severe symptoms
- high fever and chills
- Flulike symptoms
- cough productive of “Currant jelly” like sputum (bloody)
Klebsiella radiographic clues
- extensive lobar consolidation
- air bronchograms
- bulging fissure sign
- cavitary lesions (gas filled space in an area of consolidation)
Tx of Klebsiella pneumonia
- usually extended spectrum b-lactamase positive so resistant to B-lactam and B-lactamase inhibitors, co-resistance to all FQs and often aminoglycosides
- use: imipenem-cilastatin
or meropenem
legionella characteristics, and tx
- GI sxs, especially diarrhea
- neurologic findings, especially confusion
- Fever > 39 C
- gram stain of resp. secretions shows many neutrophils, but few, if any, microorganisms
- hyponatremia
- hepatic dysfunction
- hematuria
- failure to respond to b-lactam and/or amino glycoside abx
- not transmitted from person to person
- from contaminated water supply
- macrolides or resp. FQ for tx
staph aureus pneumonia
- often seen post influenza
- secondary bacterial infections typically establish during the second week of a viral infection. During viral clearing and recovery data suggest susceptibility is due to impaired innate immunity against bacterial infection following adaptive immune response to viral infection
- MRSA assoc. with high mortality and necrotizing pneumonia
Pseudomonas pneumonia
- 2nd most common cause of nosocomial pneumonia
- gram -
- cough productive of purulent sputum, dyspnea, fever, chills, confusion, and severe systemic toxicity
- characteristic sweet, grape-like odor
- elaboration of green pigment
RFs of pseudomonas pneumonia
- Bronchiectasis (cystic fibrosis)
- repeated abx use
- prolonged oral glucocorticoid use in pts with structural lung disease (COPD, pulmonary fibrosis)
- immunocompromised
- previous hospitalizations
General tx for nosocomial PNA
Imipenem or meropenem: if suspect Legionella add Levofloxacin or Moxifloxacin
if suspect MRSA -> + Vanco
if suspect pseudomonas:
Imipenem, or cefepime, or piperacillin tazobactam (Zosyn) + cipro or Tobramycin
Prevention of nosocomial pneumonia?
- avoid acid-blocking meds (use sulfcralfate instead in hospitalized pts - coats gastric lining w/o altering pH) - decontamination of oropharynx -> mouthwash - pt positioning - subglottic drainage (Special ETT) - preventing aspiration - handwashing - clean equipment
Group A strep?
rare in US but especially deadly. GAS can cause a fulminant pneumonia with early empyema formation even in young, immunocompetent hosts
- acute and rapidly progressive respiratory failure and pulmonary hemorrhage
