Pulmonary Pathology II Flashcards
Clinical findings of IPF
Basilar infiltrates, leading to honeycombing
Dyspnea
Velcro rales
Restrictive pattern on PFT (dec. DLco, FVC)
Contributing factors to development of IPF
Environment - industrialized places, smoking.
Genetics
Age >50 y/o
How is IPF DX?
High-res CT or pulmonary BX.
What will a pulmonary BX show in IPF?
Usual interstitial pneumonia
- normal areas
- inflammation
- fibroblast foci
- peripheral honeycombing
How long do patients die after receiving DX of IPF?
Approx 3-5 years from respiratory DZ
What are some therapies to treat IPF? (2)
Lung transplant
Meds to arrest fibrosis (tyrosine kinase inhibitors and TGF-beta inhibitors)
Non-specific interstitial pneumonia (NSIP) develops how?
What is its histology?
What is the prognosis?
Idiopathic.
Has unique histology:
- uniform infiltrates (uniform inflammation/fibrosis)
- no hetergeneity
- no fibroblast foci
- no granulomata
Better than usual interstitial pneumonia (UIP).
Cryptogenic organizing pneumonia (COP or BOOP) presentation:
What is seen on histology?
How is it DX?
What is the prognosis?
Pneumonia-like consolidation. 5th/6th decades of life.
Fibroblast foci (Masson bodies) - organizing plugs of CT.
DX of exclusion - not infections, drug or toxin induced or related to CT DOs.
Prognosis is good, and pts. tend to fully recover w/ steroids.
Which Autoimmune or CT DZs can manifest as ILD? (3)
Which ILDs? (3)
RA, Systemic sclerosis, SLE
UIP, NSIP, Organizing pneumonia (BOOP)
What determines the prognosis of an autoimmune-related cause of ILD?
The underlying AI DZ.
Sarcoidosis def:
Clinical presentation:
Systemic DZ manifesting non-caseating (non-necrotizing) granulomata.
Presentation is usually incidental on CXR or dyspnea.
What is seen on histology in a patient w/ sarcoidosis?
Granuloma inclusions including:
- asteroid bodies
- Schaumann bodies
What is the demographic for pts. w/ Sarcoidosis?
What is the COD?
<40 y/o
10x many in AA
COD may be from pulmonary, cardiac or neurologic involvement.
What enzyme is elevated in a pt. w/ Sarcoidosis?
ACE
Hypersensitivity pneumonitis may mean prior exposure to: (3)
Immune reaction to inhaled Ag
- Pigeon-feeder’s lung
- Farmer’s lung: Actinomycetic spore in hay
- Hot-tub lung: reaction to mycobacterium avium complex (MAC)
What typically exists in a patient w/ Hypersensitivity pneumonitis?
DX of HP requires:
Airway-centered granulomata w/ associated lymphocytes
Hx
Desqaumative interstitial pneumonia (DSIP) presents in what age/patient?
What kind of lung DZ is it?
What does histology show?
What is the prognosis?
Tx?
Smokers in 4th-5th decades.
Restrictive lung DZ.
Histology shows characteristic “stuffed” alveolar spaces full of Mo.
Good prognosis, >95% survival at 5 yrs.
Smoking cessation, corticosteroids.
Respiratory Bronchiolitis-Interstitial Lung DZ (RB-ILD):
What age/patient does it present in?
How is DX made?
Part of a spectrum w/ DSIP, but less symptomatic and earlier presentation.
Smokers in 3rd-4th decades.
CXR abnormalities prompt BX for DX.
What 3 features exist in the histology of RB-ILD?
Is it reversible?
Mo present to lesser extent than DSIP.
Peribronchiolar metaplasia (abnormally located ciliated cells).
Possible fibrosis in advanced stage.
Can be reversible w/ smoking cessation if caught early enough.
Langerhans cell histiocytosis presents in what patient population?
What is the pathologic progression?
What exists on histology?
Reversible?
Young smoker w/ stellate lung lesions
Progressive scarring leads to cysts. Cysts may rupture and present w/ PTX.
Eosinophils, Langerhans cells, varying fibrosis and cysts.
Possible w/ smoking cessation
Pulmonary alveolar proteinosis def:
What accumulates?
Tx?
Impairment of surfactant metabolism due to defect in granulocyte-macrophage colony stimulating factor (GM-CSF). Can be AI (most common), secondary or hereditary (rare).
Surfactant accumulates throughout alveoli and airspaces.
Tx w/ subQ GM-CSF.
Pulmonary infarct gross appearance
Wedge-shaped lesions. Begins as hemorrhagic, then fibrosis sets in.
What setting can cause a bone marrow embolism?
Trauma
What patients do talc embolism occur?
IV drug users
How can IE lead to embolism?
A vegetation from a valve can break off and get lodged in the pulmonary vasculature
What is the definition of pulmonary HTN?
Pulmonary artery pressure greater than 25 mmHg
What are the WHO subgroups of pulmonary HTN? (5)
Pulm. arterial HTN (PAH) - primary vascular DZ
Secondary to LHF
Secondary to chronic pulm parenchymal DZ or hypoxia
Secondary to thromboembolic pulm DZ
Multifactorial
2 major histological features of pulmonary HTN
Plexiform lesions
Medial hypertrophy (SM in small arteries)
Goodpasture syndrome tends to occur in what patients?
What is the pathogenesis?
What is the clinical DZ a result of?
Males in their 2nd-3rd decades.
Abs against non-collagenous subunit of collagen IV.
Clinical DZ results from AB-mediated damage to basement membranes in lung and kidney.
What type of hypersensitivity is Goodpasture syndrome?
Type 2
What is the leading COD in children >5 y/o?
Pneumonia
Pneumonia is the most common cause of:
Sepsis and septic shock (50%)
4 stages of lobar pneumonia
- Congestion: vascular engorgement.
- Red hepatization: red cells and inflammation.
- Grey hepatization: inflammation and debris.
- Resolution: fibrosis, Mo clean-up.
What are some complications of lobar pneumonia?
Abscess
Empyema
Bacteremia
Community-acquired bacterial pneumonia can be from what pathogens?
S. pneumoniae H. influenzae S. aureus K. pneumoniae P. aeruginosa L. pneumophilia M. pneumoniae
Most common cause of commuity-acquired bacterial pneumonia is:
What do these bacteria look like?
What is the vaccine recommendation?
S. pneumoniae
Lancet-shaped G+ diplococci
Vaccination recommended for infants, pts. >65 y/o and in respiratory DZ/smoking Hx.
H. influenzae is more prevalent among:
Vaccine recommendation?
Most prevalent amongst kids.
Vaccine recommended for type B for kids <5 y/o.
S. aureas can cause ______ formation.
What patients is it seen in most?
Abscess formation.
Mostly seen in IV drug users.
K. pneumoniae is seen most in what patients?
What does the sputum look like?
Alcoholics.
Currant jelly sputum.
P. aeruginosa is seen in tandem w/ what DZ?
CF
Typical pneumonia
Onset:
SX:
On CXR:
Pt. pop:
Onset: abrupt
SX: respiratory predominate
On CXR: consolidation
Pt. pop: older adults or young kids
“Atypical” or Walking Pneumonia
Onset:
SX:
On CXR:
Pt. pop:
Onset: slower
SX: systemic SX predominate
On CXR: patchy infiltrates
Pt. pop: young adults, teens, older kids
Common causes of atypical “walking” pneumonia
Mycoplasm pneumoniae
Legionella
Chlamydia pneumonia
Chlamydia psittaci
What is unique about Mycoplasma pneumoniae?
Smallest free-living, self-replicating microorganisms known.
No cell wall.
Legionella Gram stain:
Where is it found?
G+ bacillus
Warm freshwater, or airborne
Hemagglutinin
Neuramidase
Protein that attaches to cells.
Allows release of replicated virus from cells.
Antigenic drift
Epidemics.
Minor changes to proteins (Ags) on virus allowing increased spread.
Can be similar enough to other viruses to allow for some immunity.
Antigenic shift
Pandemics.
Genomic alterations w/ major protein changes.
No immunity for almost everyone.
Severe acute respiratory syndrome (SARS) is from what virus?
Where did it originate?
When was the outbreak?
Coronavirus
China
Worldwide outbreak from 2002-2004
3 most common causes of bacterial neonatal pneumonia
Grp B Strep
G- bacillus
Listeria
What are the most common causes of viral pneumonia in children > 1 mo?
RSV* Parainfluenze virus Influenze A/B Adenovirus Rhinovirus
What are the most common causes of bacterial pneumonia in children > 1 mo?
S. pneumoniae
H. influenzae
M. catarrhalis
S. aureus
RSV is caused by:
SX?
Paramyxovirus
Rhinorrhea, cough, wheezing, dyspnea, tachypnea, cyanosis.
Histologically, where do bacteria invade in pneumonia vs. viruses?
Bacteria invade in the alveolar spaces.
Viruses invade the interstitium.
With which 2 pneumonias can lung abscesses occur?
S. aureus
K. pneumoniae
What 3 scenarios might an aspiration pneumonia occur?
Can aspiration pneumonia lead to lung abscesses?
Chronic alcoholics
Elderly pts. (stroke)
Anaerobic bacteria
Yes
When was the Swine Flu epidemic?
What country?
Death count?
2009
Mexico
> 200K
How do bacterial vs. viral infections differ on CXR?
Bacterial: lobar or consolidated appearance.
Viral: diffuse infiltrates.
In what type of infection are epidemics more common?
Viral
3 fungi common in chronic pneumonia
Histoplasma
Blastomycosis
Coccidiomycosis
Histoplasma capsulatum is endemic in which areas?
What is the course of the infection generally?
What is the unique fungal characteristic seen on morphology?
Can it ever be more aggressive?
Midwest and Caribbean.
Usually subclinical infection w/ granulomatous response (calcifications or coin lesions on CXR).
Yeast forms “pumpkin seed” morphology.
It can have a more aggressive course in the immunocompromised.
Blastomyces dermatitides is endemic in which areas?
What does the infection cause?
What is the unique yeast form on morphology?
Where else (besides) lungs can it infect?
Central and SE US.
Granulomatous response.
Broad-based budding.
Skin, but rarely becomes disseminated infection.
Coccidiodes immitis is endemic in which areas?
What kind of infection does it cause?
What is the course?
Can it ever become disseminated?
SW US and Mexico.
Granulomatous infection w/ eosinophils.
Usually subclinical and self-limited.
Can be disseminated in the immunocompromised.
Pneumocystis jiroveci (carinii) features:
Characteristic morphology:
How does it look on CXR?
Opportunistic fungal infection. AIDS-defining illness.
Cup-shaped yeast forms.
Can be diffuse or focal or anything else.
Mycobacterium avium complex (MAC) is found mostly in what patients?
What does it look like on histology?
Immunocompromised elderly pts.
Thin mycobacterium look slender red on acid-fast stain.
What most impacts the differential for the cause of a pneumonia infection?
Setting/method of acquisition
In lung transplant patients, rejection shows which features on histology?
Mononuclear infiltrates around vessels.
What is the unique cell marker for Langerhan’s cell Histiocytosis?
What cell type is abundant on histology?
CD1a
Eosinophils clump
