Chapter 122 - Lung abscess Flashcards
Lang Abscess can be single or multiple but usually are marked by a single dominant cavity ____ in diameter
> 2cm
Definition of a primary abscess
Usually arises from ____
Principally caused by _____
Occur in ____
- usually arise from aspiration
- principally caused by anaerobic bacteria
Occur in the absence of an underlying pulmonary or systemic condition
Primary lung abscess is comprised of how many percent of cases?
80%
Two settings wherein secondary abscesses arise
Postobstructive process (foreign body or tumor )
Systemic process (HIV, immunocompromising condition)
Duration of an acute lung abscess
<4-6 weeks
How many percent of cases comprise chronic abscess
40%
Major risk factor for primary lung abscess
Aspiration
Age group and and gender commonly affected by primary lung abscess
Middle aged men
Important risk factors associated with the development of lung abscess
- Colonization of the gingival crevices by anaerobic bacteria or microaerophilic streptococci
- risk of aspiration
Causative agent causing septic emboli from tricuspid valve endocarditis
Staphylococcus aureus
Septic theombophlebitis resulting from an infection beginning in the pharynx spreading to the neck and the carotid sheath.
Syndrome & causative agent
Lemierre’s syndrome
Fusobacterium necrophorum
Most common locations of primary lung abscesses
Posterior upper lobes
Superior lower lobes
Right most commonly bec right mainstem bronchus is less angulated
True or False
Knowing the identity of the causative anaerobic isolate alters the response to treatment
False
In how many percent of primary lung abscesses will cultures turn out negative ?
40%
Term used when no pathogens are isolated from a primary lung abscess
Nonspecific lung Abscess
Refers ro cases with foul smelling breath, sputum, empyema
Putrid lung abscess
Location of secondary abscess
Varies with underlying cause
Moat common organism causing secondary lung abscess
Pseudomonas aeruginosa and other gram (-) rods
Obtaining culture material is of special i importance in which type of abscess?
Secondary
Microorganism causing lung abscess associated with high fevers and a fulminant course
Non-anaeroic such as Staphylococcus aureus
In which imaging will a thick walled cavity with an air fluid level be detected
Chest radiograph
Imaging that permits better delineation andnprovide earlier evidence of cavitation
CT scan
Recommended regimen for primary lung abscess
- Clinda 600mg IV TID
2. BL/BLIC IV
Treatment duration for lung abscess
3-4 weeks to 14 weeks
Why is metronidazole not effective as a single agent?
Does not cover microaerophilic streptococci
Size of abscess that is less likely to respond to antibiotic therapy
> 6-8cm
Mortality rate of primary lung abscess
2%
Mortality rate of secondary lung abscess
75%
Poor prognostic factors for lung abscess
Age >60 Aerobic bacteria Sepsis Sx >8weeks Size >6cm
