Download IM Anaerobic Lung Infx Presentation

Overview
• Anaerobic bacteria are the predominant component of
the bacterial flora of normal human skin and mucous
membranes and are, therefore, a common cause of
endogenous bacterial infections
• Such infections may be serious and even lifethreatening.
• They can involve all body systems and sites but most
often affect the abdominal and pelvic organs, the
respiratory system, and the skin and soft tissues
• Aspiration is the leading cause of anaerobic lung
infections
• Most common source of aspiration pneumonia are
oropharyngeal secretions or gastric contents
– Oral cavity anaerobic bacteria outnumber aerobes 10:1
Risk Factors
–
–
–
–
–
–
–
–
–
Severe periodontal or gingival disease
Depressed level of consciousness
Seizure history
General anesthesia
CNS or neuromuscular disease
Impaired swallowing
NG tube
Tracheal tube (w/ or w/o mechanical ventilation)
Poor blood supply and tissue necrosis
• Lower the oxidation-reduction potential and favor the growth of
anaerobes.
• Therefore, presence of a foreign body, malignancy, surgery, edema,
shock, trauma, colitis, or vascular disease may predispose one to
anaerobic infection.
Diagnosis
– Clinical Features
• Fever, Weight Loss, Malaise, Cough, Foul-smelling sputum
– Smell: Metabolic End-products (Organic Acids), not all produce
– Radiographic Findings
– Culture
• Polymicrobial w/ Mixed flora
• Anaerobes: Prevotella, Porphyromonas Fusobacterium,
Peptostreptococcus
• Aerobes: Beta-hemolytic & Microaerophilic Streptococci
• Isolating them requires appropriate methods of collection,
transportation, and cultivation of specimens.
Clinical Course
– Progression from pneumonitis into necrotizing
pneumonia and pulmonary abscess can occur, with or
without the development of empyema
– An anaerobic infection can itself provide a clue to and
warning of an underlying medical problem
– Lung abscess can be a clue to an underlying
bronchogenic malignancy
• Malignancy can first be detected b/c of anaerobic infx
presence
– Underlying dental infection (periodontitis or periapical
abscess) can lead to brain abscess
Treatment
– Includes proper drainage, debridement of
necrotic tissue and an antibiotic regimen
(often initially empiric) with an agent active
against anaerobic and aerobic organisms.
– Metronidazole, Clindamycin,
Chloramphenicol, Cefoxitin, Penicillin + BLactamase Inhibitor, and Carbapenems
– Often add Macrolide (Azithromycin) for S.
aureus and Aerobic Streptococci coverage