Pathology of Restrictive Lung Disease Flashcards
restrictive also known as
interstitial
interstitium of the lung is the
connective tissue space around the airways and vessels and the space between the basement membranes of the alveolar walls
restrictive lung disease has a …… FEV1 and a ……. FV and a therefore a …….. FEV1/FVC ratio
low FEV1
low FVC
normal FEV1/FVC ratio
Characteristic of restrictive lung disease
reduced gas transfer (diffusion abnormality)
Ventilation/perfusion imbalance
Diffuse lung disease presentation
discovery of abnormal CXR
Dyspnoea
Respiratory failure (type 1)
heart failure
DAD
Diffuse alveolar damage
Diffuse alveolar damage
histological pattern in lung disease
DAD is associated with…
major trauma
chemical injury/ toxic inhalation
circulator shock
drugs
infection
(but can sometimes be idiopathic)
Histological features of DADs
Protein rich oedema
fibrin
hyaline membranes
denuded basement membranes
epithelial proliferation
fibroblast proliferation
scarring (interstitial and airspaces)
Sarcoidosis
A multisystem granulomatous disorder of unknown aetiology
commonly effects young adults (F>M)
Sarcoidosis presnetation
Young adult
incidental abnormal CXR (but no symptoms)
SOB, cough, abnormal CXR
If persistent (after 2 or 3 years) sarcoidosis is treated with
corticosteroids
Sarcoidosis investigation
imaging
serum calcium and ACE
biopsy
pulmonary function tests
blood/urine/ECG eye exam
Hypersensitivity pneumonitis definition
an inflammation of the alveoli within the lung caused by hypersensitivity to inhaled organic dusts
also known as extrinsic allergic alveolitis
Hypersensitivity pneumonitis (the antigens)
thermophilic actinomycetes
brid/animal proteins
fungi
chemicals
Hypersensitivity pneumonittis
Acute presentation
fever, cough, malaise
chills (4-9 hours)
crackles, tachyopnoea, wheeze
Hypersensitivity presentation
malaise, SOB, Cough
low grade illness
crackles some wheeze
can lead to respiratory failure (low gas transfer also)
Histopathology of hypersensitivity pneumonitis
immune complex mediates combined type III and type IV hypersensitivity reaction
Usual interstitial pneumonitis (UIP)
is a form of lung disease characterized by progressive scarring of both lungs
UIP can be seen in
connective tissues diseases
drug reactions
post infection
industrial exposure (asbestos)
(progressive disease -most dead in about 5 years)
Histopathology of UIP
patchy, interstitial chronic inflammation
type II pneumocyte hyperplasia
smooth muscle and vascular proliferation
UIP clinical symptoms
dyspnoea
cough
basal crackles
cyanosis
clubbing
UIP
basal and posterior fibrosis with honeycombing
Type I respiratory failure is PaO2 less than
8kPa
Type II respiratory failure is PaCO2 greater than
6.5 kPa
Hypoxaemia
alveolar hypoventilation
shunt
V/Q imbalance
diffusion impairment
Fall in PaO2 due to HYPOventilation is corrected by raising
FIO2 (fraction of inspired air which is oxygen)
Shunt
blood passing from right to left side of heart WITHOUT contacting ventilated alveoli
3 main types of interstitial lung disease are
idiopathic pulmonary fibrosis
sarcoidosis
hypersensitivity pneumoitis
Pleural causes of interstitial lung disease
pleural effusion
pneumothorax
pleural thickening
Muscles causes of interstitial lung disease
Amyotrophic lateral sclerosis
sub-diaphragmatic causes of interstitial lung disease
obesity
pregnancy
skeletal causes of interstitial lung disease
Kyphscoliosis
Rib fractures
Thoracoplasty
Sarcoidosis histological hallmark
non-caveating granuloma
Sarcoidosis further investigation
bronchoscopy
including biopsies and ultrasound
