Riassunto esame Pneumologia, prof. Centanni, libro consigliato Lung Pathology, Robbins

• anti-inflammatory therapy: administration of local or systemic glucocorticoids

• surgery or lung transplantation: they might be considered in refractory or advanced cases;

Complications:

• recurrent infections and repeated courses of antibiotics → microbial resistance → combination of antibiotics

• “ “ may lead to injury of the superficial mucosa → bleeding or requiring intubation-hemoptysis

• Prognosis:

• outcomes vary widely with the underlying etiology

• PFs are: frequency of exacerbations; specific pathogens involved;

• Prevention:

• reversal of the underlying immunodeficient state and vaccination

• smoking cessation

• administration of antibiotics daily 1-2 w per month (rotating schedule of antibiotics)

Lung abscess refers to a microbial infection of the lung resulting in necrosis of the pulmonary

parenchyma.

Classification (clinical and pathologic features):

• tempo of progression:

- acute vs chronic: threshold is at 4-6 weeks

• presence or absence of underlying lesion:

- if occurring during tumors or systemic conditions are defined as secondary, if not primary;

• microbial pathogen responsible:

- if no pathogens are recovered from the sputum → nonspeficic lung abscess

- if putrid lung abscess (foul-smelling breath, sputum or empyema fluid) → anaerobic bacteria are the cause for it

Etiology:

• variety of microbial pathogens cause lung abscess

• M. Tubercolosis → very important cause of pulmonary infections and abscess formation

• S. Aureus → especially in a young, previously healthy patient and in conjunction with influenza;

• K. Pneumoniae → in an immunecompromised host

• if multiple lung abscesses result from septic emboli (tricuspid valve endocarditis)

• pulmonary infarction, bronchiectasis, necrotizing carcinoma and cycsts may resemble lung abscess at imaging

Clinical features:

• usually is an indolent infection evolving over several days or weeks

• periodontal infection is a common feature

• symptoms are:

- fatigue, cough, sputum production and fever;

- usually with weight loss and anemia;

o putrid smelling sputum → anaerobic bacteria due to production of short-chain fatty acids

- pleuritis sometimes due to involvement of the pleura → it may be the symptom prompting medical evaluation

• CT reveals the evolution of the lesion from pneumonitis to cavitation (requiring 7-14 days)

Diagnosis:

• standard imaging, chest x-ray and CT, is required with the latter clearly preferred

• microbiologic studies (stain and culture) → anaerobes are not detected in expectorated sputum culture even if they are

the most common causes of primary lung abscesses

• pleural fluid specimens promptly obtained by thoracentesis and BAL for anaerobes;

• transthoracic needle aspiration CT-guided is also performed to avoid contamination by the flora of the upper airways;

Treatment: