pathology of restrictive lung disease Flashcards
what is the interstitium of the lung
the conective tissue soace around the airways and vessels and the soace between the basement membtanes of alveolar walls
what are the featires of restrictive diffuse interstitial lung disease
reduced lung compliance - stiff lungs
low FEV1 and low FVC but FEV1/FVC normal ratio
reduced gas transfer (Tco or Kco)
- diffusion abnormality
ventilation/perfusion imbalance
- when small airways affected by pathology
how does diffuse lung disease present
discovery of abnormal CXR or CT
dyspnoea
- shortness of breath on exertion
- shortness of breath at ready
resp failure - type 1
heart failure
what are chronic responses as a resukt to parenchymal (interstitial) lung injury
usual intersitial pneumonitus (UIP)
granulomatous responses
other patterns
what is an example of an acute response
diffuse alveolar damage (DAD)
what is DAD associated with
makor truama chemical injury/toxic inhalatjon circulatory shock drugs infection including viruses auto(immune) disease radiation
what are histological features of DAD
protein rich oedema fibrin hyaline membranes denudes basement membranes epithelial proliferation fribroblast proliferation scarring - interstitium and airspaces
what are examplea of acite granulomatous response
sarcoidosis
hypersensitivity pneumonitis
what is sarcoidosis
a multisystem granulomatous disorder of unknown aetiology
what is the histopathology of sarcoidosis
epitheliod and giant cell granulomatous necrosis/ caseation very unusual little lymphoid infiltrate variable associated fibrosis type 4 hypersensitivity
what organs are involved in sarcoidosis
lymph nodes lung spleen liver skin, eyes, skeletal muscle bone marrow salivary glands
how does sarcoidosis present
acute arthralgia erythema nodosum bikateral hikar lymphadenopathy incidental abnormal CXR or CT SOC, cough and abnormal CXR
how do you disgnose sarcoidosis
clinical findings imaging serum calcium and ACE biopsy kveim test tuberculin test
what is hypersensitivity pneumonitis
reaction to organic molecules or antigens thermophilic actinomycetes - farmers lung - micropolyspora faeni - thermoactinomyces vulgaris bird animal proteins - faces and bloom fingu - asoergillus spp chemicals others
what is the acute oresentation of hypersensitivity pneumonitis
fever drt cough myalgia chills 4-9 hds aftr ag exposure crackles, tacgypnoea, wheeze precipitating antibody
what is the chronic presentation of hypersensitivity pneumonitis
insidious malaise SOB cough low grade illness crackles and some wheeze
what is the histopathology of hypersensitivity pneumonitis
immune complex mediated combined type 3 and 4 hypersensitive reactjon
soft centriacinar epitheliod granulomata
interstitial pneumonitis
foamy histoocytes
bronchiolitis obliterans
upper zone disease
what is a thoe of UIP
isiopathic pulmonary fibrosis
wbere is UIP found
may be seen in connective tissue disease
drug reaction
post infection
industrial exposure
most are idiopathic - hence idiopathic fibrosis
what do chronsic reactions lead to in restrictive lung disease
honeycomb lung
what is the histopathology of UIP
patchy interstitual chronic inflammation type 2 pneumocyte hyoerplasia smooth muscle amd vascukar proliferagion evidence of old and recent injiry - temporal heterogeneity - spatial heyerogeneity
proliferating fibroblastjc foci
clinicak presentations of UIP
over 50s dyspnoea cough basal crackles cyanosis clubbing progressuve disease most dead in 5 yrs Cxr restruced PFT and reduced gas trabsger poor prognosis
