Ch 12: Intro, Bronchi/-al Disease and Infection

Question 1

Board Review! Define: Type I Alveoli vs Type II cells. Clara cells, goblet cells, basal cells.
How many blood supplies does the lung have

Answer 1

TI: 95% epithelial cellls vs TII: make surfactant
Clara: accumulate and detox inhaled toxins
Goblet: mucus secreting
Basal: precursor cells
2 blood supplies: pulmonary (deoxygenated) and bronchial (oxygenated)

Question 2

Defense Mechanisms of the Respiratory tract?

Answer 2

Nose and trachea: warm/humidify and nose hairs trap particles greater than 10um
Mucociliary blanket: 2-10um trapped and disposed of by mucociliary escilator
Alveolar macrophages: from bone marrow, mop up the rest

Question 3

Extralobar and Intralobar sequestration

Answer 3

Extra: mass of lung not connected by bronchial tree, outside visceral pleura, abnormal artery from aorta supplies it–>detected early–>dyspnea and cyanosis
Intra: mass of lung tissue within visceral pleura, isolated from tracheobronchial tree, supplied by systemic artery–>almost always in lower lobe–>honeycomb cystic changes–>discovered in adolescent

Question 4

Long Card:
Pneumonia Signs
3 Types and associated diseases

Answer 4

Fever/chills, pleuritic chest pain from stretching pleura while breathing, cough w/ yellow/green or rusty sputum, decreased breath sounds dull to percussion and increased WBC
Lobar: Entire lobe is consolidated (Strep pneumoniae and Klebsiella pneumoniae)
Bronchopneumonia: Scattered solid foci in same or several lobes (S. aureus, Haemophilus influenza, Pseudomonas aeruginosa)
Interstitial: Diffuse alveolar damage (Mycoplasm, Chlamydia, RSV, Influenza)

Question 5

Name the 4 stages of Lobar pneumonia

Answer 5

Congestion: organisms fill alveoli
Red hepatization: Capillary congestion leads to outpouring of PMNs and intraalveolar hemorrhage into the alveoli
Grey Hepatization: Macrophages come in to clean up the PMNs and blood cells
Resolution: Type II alveolar cells proliferates and restructure lung tissue: MOST undergo resolution with ANTIBIOTICS

Question 5

What are some common causes of atelectasis

Answer 5

Deficiency of surfactant, compression of the lungs, (pneumothorax following and injury), bronchial obstruction (initial inflammatory bronchiolitis is followed by bronchiolar scarring and fibrosis)

Side Note:

• Compression of lung causes mediastinum shift away from the affected side
• Obstruction causes deviation toward the affected side

Question 7

Irreversible dilation of bronchi caused by destruction of bronchial wall muscles and elastic elements. Hemoptysis, thick mucopurulent secretions; dyspnea and wheezing variable.

Answer 7

Bronchiectasis
Commonly associated with cystic fibrosis, dyskinetic ciliary syndrome (KARTAGENERS or Radial Spoke/Sturgess syndrome), hypogammaglobulinemia (low IgG)

Question 8

Normal flora of the nasopharynx that can cause severe acute inflammation with spreading edema due to altered respiratory tract defenses (commonly following influenza in immune compromised). Protein-rich edema fluid containing numerous organisms fills the alveoli with a predominance of PMNs. Name that bug. What type of pneumonia is this bug associated with?

Answer 8

Streptococcus pneumonia (pneumococcal pneumonia).
Classic bug of Lobar pneumonia

What is the other classic lobar bug!?

Klebsiella pneumoniae: current jelly sputum!

Question 9

A patient shows a distinct cavity on chest x-ray. Histology shows a LOCALIZED accumulation of pus accompanied by destruction of pulmonary parenchyma. What do we call this pathology?

This pathology is most commonly associated with aspiration and lung cancer. What are some clinical clues/risk factors to aspiration pneumonia and are aerobic or anaerobic more common? Do these occur proximal or distal to the site of tumor blockage in a lung.

Answer 9

Pulmonary Abscess

A state of depressed consciousness predisposes the patient to aspiration (alcoholism, drug overdose, epilepsy, neuro impairment)
Anaerobic account for 90% of cases. Typically polymicrobial (fusiform bacteria and Bacteroides spp)
Distal to the site of blockage

Fun Fact: Aspiration pneumonia more common in right lower lobe

Question 10

Common complications of pneumococcal pneumonia: Pleuritis, Pleural effusion, Pyothorax, Empyema, Bacteremia
RARE complication: Pulmonary fibrosis, Lung abscess
Describe all common and pulmonary fibrosis

Answer 10

Pleuritis: inflamed pleural space causes a sharp pain
Pleural effusion: excess fluid accumulates between two pleural spaces
Pyothorax: infection of a pleural effusion
Empyema: loculated collection of pus with fibrous walls following spread of bacterial infection to PLEURAL SPACE
Bacteremia: organisms disseminate into the blood
Fibrosis: intra-alveolar exudate organizes to form intra-alveolar plugs of granulation tissue and fibrosis leads to shrunken lung

Question 11

Highly common superinfection after influenza or other viral infections. Also common in chronically ill patients prone to aspiration or who are intubated. Name that bug! Is it more commonly community acquired or nosocomial? What type of pneumonia does it cause? What is a common complication in infants?

Answer 11

Staphylococcus aureus
Bronchopneumonia
Nosocomial
Pneumatoceles: thin-walled cystic spaces lined primarily by respiratory tissue. Develops when an abscess breaks
Cavitation and pleural effusion also common

Question 12

Most opportunistic pneumonia is caused by (class). Name the two most common and what they are associated with.

Answer 12

Gram negative bacteria!
E.coli: Gastrointestinal and urogenital surgery
P.aeruginosa: immunocompromised, burns, CYSTIC FIBROSIS!!! (bronchopneumonia)

Question 13

An insidious pneumonia with a prolonged course and minimal respiratory symptoms is called as:
What are the two main causes.
Classify the pneumonia.

Answer 13

Atypical pneumonia
Mycoplasma (lack rigid cell wall) and viral infections
Interstitial pneumonia

Question 14

In a question stem, they seem to keep focusing on the fact that the patient is an avid bird lover with pneumonia. What are the three most common bugs that should be going through your mind. What if the patient is immune compromised too!?

Answer 14

Chlamydia psittaci, Histoplasmosis and Cryptococcus
Cryptococcus in immune compromised (thick mucoid capsule seen on mucicarmine stain (India Ink))

Side note: Histoplasmosis, Coccidioidmycosis, and Blastomycosis both act like TB with ghon complex resembling lesions. H and C have granulomatous nodules while C and B have purulent center in their granulomas

Question 15

This disease has a primary and secondary stage. It remains in the system due to an inability of macrophages cannot readily kill the bacteria.
What is the lesion called in primary disease?
What do we call these lesions when they enlarge and associate with a lymph node?
What mights happen in young children who are immunosuppressed

Answer 15

Mycobacterium tuberculosis.
Ghon lesions: peripheral parenchymal granuloma (often in UPPER lobes; MACROPHAGES)
Ghon complex forms when they enlarge and associate with a lymph node–> well circumscribed and centrally necrotic, later becomes fibrotic and calcified
Young: Progressive primary TB: central liquefaction and dissemination of primary disease

Side note: Primary TB usually relatively asymptomatic

Question 16

Explain how secondary TB occurs. Describe the lung morphology.
Name some complications of secondary TB.
What are the common symtoms of secondary TB?

Answer 16

Reactivation of primary TB due to immunosuppression (AIDS, elderly commonly).
Diffuse, fibrotic, calcified caseous necrosis (granuloma formation by macrophages).
Complications: Miliary TB (mulitple small granulomas), Hemoptysis, bronchoplueral fistula, laryngitis, intestinal TB, ASPERGILLOMA (more later!)
Fever, night sweats, cough with hemoptysis

Pathoma Facts: Can spread to meninges, cervical lymph nodes, kidney (sterile pyuria), pott disease (vertebral lumbar)

Question 17

The invasive form of this disease is typically an opportunistic infection following AIDS or other causes of immune suppression.
The non-invasive form normally fill cavities left behind by tuberculosis.
What other underlying disease predisposes someone to the bronchopulmonary form?

Answer 17

This is Aspergillosis!
The invasive form can invade the blood vessels and cause infarction of lung tissue
The non-invasive form forms a aspergilloma or “fungus ball”
Asthmatics are predisposed to bronchopulmonary form
Clinical signs: wheezing, chest pain, cough, thick mucous plugs

Question 18

Single, dark, basophilic nuclear inclusion with peripheral halo and multiple, indistinct cytoplasmic, basophilic inclusions. Common in infants/neonates or immune compromised.

Answer 18

Cytomegalovirus

Question 19

Symptoms are similar to those of tuberculosis and result in an extensive infiltrate of macrophages in AIDS patients

Answer 19

Mycobacterium Avium-Intracellulare

Question 20

This organism multiples in macrophages following phagocytosis and are then released to infect other macrophages. What type of environment do we find these in? What is the time course of the symptoms?

Answer 20

Legionella Pneumonia
Thrive in aquatic environments (contaminated water in air-conditioning cooling towers, evaporative condensers and construction sites)
Abrupt onset of malaise, fever, muscle aches, and (strangely) abdominal pain

Question 21

This fungus contains an interstitial infiltrate of PLASMA CELLS AND LYMPHOCYTES with diffuse alveolar damage and hyperplasia of type II pneumocytes.
Common in AIDS patients.

Answer 21

Pneumocystis jiroveci
Most common cause of pneumonia in AIDS patients
Alveoli filled with a FOAMY EXUDATE with organisms appearing as small bubbles in a background of proteinaceous exudate
Silver impregnation makes cysts appear as a round/indented CRESENT MOON

Question 22

Pneumonia class which includes mycoplasm, chlamydia, and most viral illnesses (RSV and Influenza)

Answer 22

Interstitial Pneumonia: Hyaline membrane formation with necrosis of type I pneumocytes and hyperplasia of type II pneumocytes
Little intraalveolar cells (can have edema in later stages)

Side Note: RSV causes most damage in infants
Influenza: huge cause of superinfection with bacteria following illness

Question 23

Buzzword Bingo!!

1. Eosinophilic nuclear inclusions surrounded by a clear halo and SMUDGE CELLS
2. Filamentous bacteria, small lung abscesses, SULFUR GRANULES
3. Beaded, thin filaments that branch at RIGHT ANGLES
4. Epiglottitis with respiratory infection

Answer 23

1. Adenovirus
2. Actinomycosis
3. Nocardia
4. Haemophilus influenzae (A Bronchopneumonia of importance from Pathoma)

Question 24

1. Rare condition in which alveoli are filled with a granular, proteinaceous, eosinophilic material that is PAS-positive.
2. Hyaline membranes form with thickening of the alveolar walls and loose connective tissue presence. Associated with diffuse alveolar damage beginning 1 week after initial injury. Heavy fibroblast proliferation in alveolar walls.
3. Nonspecific pattern of reaction to injury of alveolar epithelial and endothelial cells from a variety of insults. Relation with acute respiratory distress syndrome.

Answer 24

1. Alveolar Proteinosis
2. Pulmonary fibrosis
3. Diffuse alveolar damage