Lecture 60 - Dx and Tx of PNA

Question 1

Define PNA:

Answer 1

• “an abnormal inflammatory condition of the parenchyma of the lung ”

Question 2

What are the classifications of PNA?

Answer 2

CAP: Typical vs Atypical

Nosocomial: HAP, VAP, HCAP

Aspiration

Opportunisitic (Immunocompromised host)

Question 3

PNA in general (CAP typical?) — symptoms?

Signs?

Answer 3

Symptoms
§ Cough – productive vs non productive, +/- hemoptysis

§ Chest pain – pleuritic vs non-descript

§ Dyspnea - SOB –

§ Constitutional – malaise, fever, weight loss, night sweats, anorexia

Signs:
Tachypnea, tachycardia, hypoxemia, crackles
consolidation (dullness to percussion, egophony)

Question 4

Differentiate signs and symptoms of PNA vs Acute Bronchitis

Answer 4

PNA - cough, fever, ABN VITALS, Tachypnea, crackles, consodlidaiton
Opacities CXR

Acute Bronchtiis –
cough (+/- fever),
Normal vitals
Rhonchi, wheezes, crackles

Normal CXR

Question 5

Imaging – CXR findings of

• lobar PNA
• Atypical PNA
• Aspiration PNA

Answer 5

Lobar – consolidation to 1 or more lobes

Atypical – NO CONSOLIDATION; increased marking of the interstitium; diffusely

Aspiration – consolidation of dependent lobes (RLL, RML)

Question 6

Are PFTs used for the dx of PNA?

how is the clinical Dx of PNA made?

Answer 6

No – not very useful

Clinical dx is made on CXR

Question 7

what are some predisposing risk factors for PNA?

How can bacteria reach the lungs?

Answer 7

redisposing factors:
• Loss or suppression of cough reflex; injury or defect to mucociliary, impairment of the phagocytic process, pulmonary congestion; accumulation of secretions

Bacteria can enter the lungs via inspiration, aspiration, hematogenous

Question 8

what are some predisposing risk factors for a nosocomial PNA?

Answer 8

host factors, prior antibotics, invasive devices, medications altering gastric pH

Question 9

what are some common pathogens that cause typical CAP ?

Answer 9

S. Pneumonia (majority) 
S. Aureus -- IVDU, foreign body, 
Klebsiella 
H flu 
Catarrhalis

Question 10

what are some bacterial causes for atypical pneumonia?

Answer 10

Mycoplasma pneumonia

Legionella

Chlamydia

Question 11

What viruses are known to cause atypical PNA

Answer 11

CMV
RSV
Influenza
Parainfluenza

Question 12

Causes of Nosocomial PNA:

early onset vs late onset

Answer 12

Early Onset: S. Pneumo, MSSA, H flu, anaerobes

Late Onset – Pseudomonas, klebsiella, serratia, enterobacter, MRSA

Question 13

Who needs to be cultured to purse a definitive etiology?

Answer 13

Severe CAP, failure of out patient threapy, nosocomial, pt has structureal disease, liver disease, alcohol abuse, asplenia

Question 14

Causes of aspiration PNA?

CXR?

Answer 14

Anaerobes (Bacteroides, fusobacter)

CXR – dependent lobar opacities

Question 15

Fungal PNA –

causes-

endemic vs opportunisits

Answer 15

Inhalation or hematogenous spread

endemic: histo, blasto, cocci

Opportunistic – candida, aspergillus, cryptococcus,

Question 16

where is coccidiodes found?

where is histoplasma cfound?

Answer 16

Cocci – SW USA

histo – bat/birds droppings, caves