Singh Pathology of Respiratory System #4

Question 1

What is the most common cause of sepsis and septic shock?

Answer 1

Pneumonia

Question 2

What are the stages of lobar pneumonia?

Answer 2

1. Congestion with vascular engorgement
2. Red hepatization with red cells and inflammation
3. Grey hepatization with inflammation and debris
4. Resolution with fibrosis and macrophage clean up

Question 3

Complications of lobar pneumonia?

Answer 3

Abscess

Empyema

Bacteremia

Question 4

What is the most common cause of community acquired pneumonia?

Answer 4

• Streptococcus pneumoniae
  
  • pairs and chains of lancet shaped gram positive diplococci

Question 5

What are 3 other bacterial causes of CAP besides S.pneumonia? What are their characteristics?

Answer 5

• Haemophilus influenzae
  
  • virulent pneumonia in kids
• S. aureus
  
  • abscess forms
  • IV drug user
• K. pneumoniae
  
  • alcoholics
  • currant jelly sputum

Question 6

What characterizes typical pneumonia?

Answer 6

• abrupt onset
• respiratory sx predominate
• Consolidation on CXR
• Older adults or young kids

Question 7

What characterizes Atypical (walking) pneumonia?

Answer 7

• Slow onset
• Systemic symptoms predominate
• Patchy infiltrates on CXR
• Young adults teens

Question 8

What bacteria are responsible for atypical pneumonia?

Answer 8

• Mycoplasma pneumoniae
• Legionella pneumophila
• Chlamydia pneumonia
• Chlamydia psittaci

Question 9

Describe Legionella pneumophila?

Answer 9

• Gram negative bacillus
• Gros in warm freshwater
  
  • air conditioning units
  • misters
  • hot tubs
• Airborne

Question 10

What is the most common viral CAP?

Answer 10

• Influenza

Question 11

What two proteins make up influenza virus?

Answer 11

• Hemagglutinin
  
  • attaches to cells
• Neuraminidase
  
  • allows release of replicated virus from cell

Question 12

What is antigenic drift?

Answer 12

• minor changes to proteins that are just enough to allow increased spread (epidemic)
• Similar enough to original virus to allow for some immunity

Question 13

What is antigenic shift?

Answer 13

• Genomic alterations with major resulting change to protein structures
• Naïve immunity for almost all people
• Pandemics
• Picked up from animal gene products

Question 14

What kind of virus is COVID-19?

Answer 14

Positive sense ssRNA

Question 15

How does COVID 19 lead to ARDS?

Answer 15

Induces a cytokine storm

Question 16

How does COVID 19 induce coagulopathy? How do you test for it?

Answer 16

• Venous and arterial thrombi
• Megakaryocyte activation
• D dimer predictive value

Question 17

What causes neonatal bacterial pneumonia?

Answer 17

• Group B strep
• Gram - bacilli
• Listeria

Question 18

What are the viral and bacterial causes of pneumonia in kids less than 1 month old?

Answer 18

• RSV
• Parainfluenza virus
• Influenza A and B
• Adenovirus
• Rhinovirus
• S. pneumoniae
• H. influenzae
• M. catarrhalis
• S. aureus

Question 19

Signs and sx of influenza?

Answer 19

• Abrupt onset
• Fever 3-4 days
• Severe aches
• Chills
• Fatigue and weakness
• Headache common

Question 20

Which type of viral class has the most direct route to viral proteins?

Answer 20

• ssRNA + sense virus
• they go straight to ribosome and begin translation

Question 21

RSV Pneumonia symptoms?

Answer 21

• paramyxovirus
• Rhinorrhea and cough
• Wheezing dyspnea
• Tachypnea
• Cyanosis

Question 22

Presentation of bacterial pneumonia?

Answer 22

• Abrupt onset
• Not associated with epidemics
• may have bacteremia
• High grade fever
• Crackles
• Lobar or consolidated appearance
• May involve pleura

Question 23

Viral presentation of pneumonia?

Answer 23

• gradual onset
• epidemics are common
• Not associated with viremia
• No fever or low grade
• Wheezes
• Diffuse infiltrates on CXR
• Doesn’t involve pleura
• Self limiting

Question 24

Complication of pneumonia?

Answer 24

• Lung abscess
• Aspiration

Question 25

Why would the right middle and lower lobes be preferentially afcted?

Answer 25

* The right main bronchi has a steeper slope making it more favorable for anything to fall that way

Question 26

What is a ghon complex?

Answer 26

Caseating granulomata is found in the hilar lymph nodes and at the parenchyma

Question 27

What diseases cause pulmonary granulomatas?

Answer 27

* TB * Sarcoidosis * Hypersensitivity pneumonia * Vasculitis (GPA)

Question 28

What is chronic pneumonia? What is the biggest cause?

Answer 28

* Pneumonia lasting for months in a immunocompetent patient * Fungal infections are the most common cause * Histoplasma * Blastomycosis * Coccidiomycosis

Question 29

Histoplasma Capsulatum, where is it endemic and what is the characteristic?

Answer 29

* Endemic in Midwest and Caribbean (ohio and mississippi river valleys) * Characteristic yeast shows pumpkin seed morphology * Subclinical infection with granulomatous response * calcification or coil lesion on CXR

Question 30

Blastomyces dermatitides endemic and characteristics?

Answer 30

* Endemic in ohio and mississippi river valley * Infections gives granulomatous response * Characteristic yeast shows broad based buds

Question 31

Coccidiodes immitis?

Answer 31

* Endemic in SW US and Mexico * Granulomatous response with eosinophils * Subclinical and self limited * Can produce disseminated infection especially with immunocompromised

Question 32

Pneumocystis jiroveci (carinii) pneumonia characteristics?

Answer 32

* Opportuinistic fungal infection * AIDS defining illness * Characteristic cup shaped yeast forms * can be diffuse or focal

Question 33

CMV Pneumonia?

Answer 33

* Opportunistic viral infection * AIDS defining illness * Characteristic inclusions in image “Cowdry”

Question 34

Mycobacterium avium complex?

Answer 34

* Immunocompromised or elderly * Thin mycobacteria seen as slender red forms on acid fast staining