9.3 Pulmonary Infections

Question 1

Pneumonia

Answer 1

Infection of the lung parenchyma that occurs when the normal defenses are impaired

Question 2

What are some signs of pneumonia?

Answer 2

• Fever and chills
• Yellow green sputum
• Tachypnea with pleuritic chest pain
• Decreased breath sounds and dullness to percussion

Question 3

Lobar Pneumonia

Answer 3

Consolidation in an entire lobe

Question 4

Bronchopneumonia

Answer 4

Scattered consolidation centered in bronchioles

Question 5

Interstitial Pneumonia

Answer 5

Diffuse interstitial infiltrates

Question 6

What are the common causes of lobar pneumonia?

Answer 6

Usually bacterial

• S. pneumoniae
• Klebsiella pneumoniae

Question 7

What will be seen on histology of lobar pneumonia?

Answer 7

Neutrophil infiltration

Question 8

What are the 4 classic phases of lobar pneumonia?

Answer 8

• Congestion
• Red hepatization - full of RBCs
• Grey hepatization
• Resolution

Question 9

What are the stem cells of the lung to regenerate it from damage?

Answer 9

Type II Pneumocytes

Question 10

What are the common causes of bronchopneumonia?

Answer 10

A variety of bacteria

• S. aureus
• H. influenzae
• Pseudomonas
• Moraxella catarrhalis
• Legionella

Question 11

What is the most common cause of secondary pneumonia?

Answer 11

S. aureus - wil cause pneumonia superimposed on a viral URI

Question 12

How does interstitial pneumonia present?

Answer 12

Presents with cough and low fever - more URI symptoms

Question 13

What is seen on the biopsy of interstitial pneumonia?

Answer 13

There will be little cells present in the alveolar sacs - most cells will be in the alveolar septa

Question 14

What are the common causes of interstitial pneumonia?

Answer 14

• Mycoplasma
• Chlamydia pneumoniae
• RSV
• CMV
• Influenza Virus
• Coxiella burnetti

Question 15

What is the most common cause of interstitial pneumonia in young adults?

Answer 15

Mycoplasma pneumoniae

Question 16

What is the most common cause of interstitial pneumonia in infants?

Answer 16

RSV - Respiratory Syncytial Virus

Question 17

What patients does influenza virus typically cause pneumonia in?

Answer 17

Elderly, immunocompromised or those with pre-existing lung disease

Question 18

What patients is Aspiration Pneumonia seen in?

Answer 18

• Alcoholics

- Comatose patients

Question 19

What are the common causes of aspiration pneumonia?

Answer 19

• Bacteroides
• Fusobacterium
• Peptococcus

Question 20

What is the classic presentation of aspiration pneumonia?

Answer 20

RLL abscess - right main stem bronchus is straighter and wider

Question 21

What is tuberculosis caused by?

Answer 21

Mycobacterium tuberculosis

Question 22

What are the signs of primary TB?

Answer 22

• Focal caseating necrosis in the lower lobe

- Foci will undergo fibrosis and calcification to form Ghon complex

Question 23

Ghon Complex

Answer 23

Typically a sub-pleural area of fibrosis and calcification that can be reactivated into secondary TB

Question 24

What are the signs of secondary TB?

Answer 24

Reactivation of Ghon complex due to AIDS/aging

- Occurs ar the apex with the formation of cavitary foci of caseous necrosis and can lead to bronchopneumonia

Question 25

What are the presentations of secondary TB?

Answer 25

• Fevers and night sweats
• Cough with heomptysys
• Weight loss

Question 26

What are the main tissues that TB can spread to?

Answer 26

• Meninges - at the base of the brain
• Kidneys
• Cervical Lymph Nodes
• Kidney
• Lumbar Vertebrae

Question 27

What is TB spread to the lumbar vertebrae called?

Answer 27

Pott Disease