Chronic Interstitial Lung Diz - Pathology Flashcards
Define chronic interstitial pulmonary disease
inflammation & fibrosis of the interstitium
(many unknown causes & pathogenesis)
chronic interstitial pulmonary disease accounts for ______% of noninfectious pulmonary diseases
15
Clinical and pathologic features of chronic intersitial lung disease that is shared with restrictive lung disease (3).
- decreased compliance
- decreased TLC
- decreased diffusing capacity
“honeycomb lung”
advanced stages of chronic interstitial fibrosis
(cor pulmonale is a possible complication)
General pathophysiology of idiopathic pulmonary fibrosis
injured/activated alveolar pneumocytes & activated immune cells release profibrogenic cytokines → fibrosis
Genetic factors associated w/idiopathic interstitial lung disease (3)
- telomerase mutation (25%)
- increased MUC5B→increased mucin → cell injury (30%)
- increased signaling in the PI3K/AKT pathway
IFP
(note the fibrosis of the lower lobes, subpleural areas and interlobular septa)
IFP: yellow arrows: dense fibrosis
(early lesions have fibroblasts, late have collagen)
Usual Interstitial Pneumonia
(fibroblasts, infiltrates, “honeycombing” & dilated air spaces lined by bronchiolar epithelium)
“honeycomb lung”: cystically dilated air spaces
(end-stage lung disease)
IPF tx
lung transplant
IPF: Prognosis
4 years
IPF sx
- early: dyspnea on exertion, dry cough
- late: hypoxemia, cyanosis, clubbing
Age of presentation: IPF
55-75 yo
“cryptogenic”
cause unknown
(ex: cryptogenic organizing pneumonia)
define cryptogenic organizing pneumonia
loose organizing CNT fills alveoli & lumen of bronchioles
_______ (3) are conditions associated w/cryptogenic organizing pneumonia.
- bacterial & viral pneumonia
- inhaled toxins, drugs
- CNT disorders
loose organizing CNT tissue
(aka “masson bodies”; note: alveoli are relatively normal)
Cryptogenic organizing pneumonia: clinical presentation (2)
- cough
- dyspnea
Cryptogenic organizing pneumonia: diagnostic findings (2)
- patchy subpleural or peribronchial areas of consolidation on CXR
- pulmonary function studies = restrictive pattern
define sarcoidosis
noncaseating granulomas in many tissues
(MC lungs & lymph nodes)
Sarcoidosis usually occurs in _______ (pt population)
- black adults > 40 yo
Sarcoidosis pathogenesis
exaggerated CD4+ T cell response to environmental antigen
(no evidence that it is infectious)
Sarcoidosis genetic factors (2)
- HLA-A1
- HLA-B8
Organs mainly affected by sarcoidosis include ______.
- hilar & mediastinal lymph nodes
- lungs
non-caseating granulomas w/scattered multinucleated giant cells (Langhans type at the arrow)
Sarcoidosis: lung bx; numerous noncaseating granulomas, some of which involve the wall of a bronchus.
The noncaseating granulomas in sarcoidosis frequently involve the walls of bronchi (found with bronchoscopic biopsy)
Sarcoidosis: noncaseating granuloma (no necrosis).
- Blue arrow: foreign body type giant cell w/overlapping nuclei in the central portion of the cell. Langhans giant cells MC.
- Yellow arrow: Asteroid bodies (star-shaped crystalline structures) are present within the foreign body type giant cell. (They are characteristically seen in sarcoidosis; however, they are not specific for sarcoidosis)
Clinical outcomes of sarcoidosis
- 70% full recovery
- 20%: lung or eye dysfunction
- 10-15% die
Sarcoidosis: general & lung specific sx
- General: Fever, Fatigue, Weight loss, Night sweats
- Lung: SOB, cough, chest pain, hemoptysis
Sarcoidosis Lab Findings (3)
- CXR: bilateral hilar lymphadenopathy (w/pulm infiltrates)
- bronchoalveolar lavage: CD4+ T cells, ⇡ TNF
- ⇡ ACE levels
(also: anergy to common skin test Ags & polyclonal hypergammaglobulinemia)
