Interstitial Lung Dz/fibrosis Flashcards
3 ways in which lung is affected in ILD
1 parenchyma (tissue) is damaged
- Walls of alveoli become inflamed (bronchioles or capillaries may be involved)
- Scarring (FIBROSIS) begins in the interstitium (tissue bwt alveoli) and LUNGS BECOME STIFF
Is ILD malignant or infectious
no
Which other dzs is ILD associated with
sarcoidosis
exposure to asbestos, coal dust, aluminum
drugs: macrobid, minocycline, amiodarone (JG), STATINS
2 main sx of ILD
and PE findings
NONPRODUCTIVE dry cough and SOB Wheezing and CP UNCOMMON PE: crackles (lower lung bases) COR PULMONALE (late) Cyanosis (late) Digital Clubbing (late) ERYTHEMA NODUSUM in sarcoidosis
Abnormal CXR shows which 3 characteristic findings
GROUND GLASS APPEARANCE (Brds!) early: Hazy opacity (ass with inflam)
RETICULAR (netlike) MOST COMMON, nodular or mixed pattern
HONEYCOMBING (small cyst spaces) is POOR PROGNOSIS
What do you expect to see on PFT?
RESTRICTIVE = interstitial:
decreased TLC
decreased FEV1 and FVC but both changes so ratio is NORMAL (or increased)
TLC
Spirometry
total amt of air in lung after full inspiration
normal is 80%
Spirometry:
FEV1 - forced expiratory volume (FEV) in 1 second )80% normal)
FVC - forced vital capacity - amnt forcefully exhaled after max inhale: all air you can exhale
ratio - normal 70-80%
what do you expect in restrictive PFT
TLC decreased
FVC decreased because can’t breath in
ratio normal
what do you expect in obstructive PFT
TLC increased (bc can't breath out?) FVC normal
Ratio is DECREASED
DLCO in ILD is
decreased (maybe the only finding in early stage)
Diffusing capacity = ability of gas to cross from air to interstitium to blood
Measure body’s ability to absorb CO from signle inhalation
Diffusing capacity of Lung for CO.
ABG
normal resting but severe exercise or sleep induced hypoxemia (may need serial excercise testing with ABGs)
or repiratory alkalosis (Low Pco2 because hyperventilating and losing CO2, so losing Hs)
GOld standard to Dx ILD
Lung biopsy to make definite Dx or to stage indicated 1) r/o CA or inf 2) to provide spec dx when: -atypical or progressive sx - <50 yo -fever, wgt loss, hemoptysis to r/o? -sx wtih normal or atyp CXR -need to confirm dx before staring serious therapy - unexplained extrapulm manifest (erythema NODOsus) - unexpl. pulm HTN, or cardiomegaly -rapid clin deterioration -sudden change in CXR
Types of lung biopsy
fiberoptic BRONCHOSCOPY with transbronchial lung biopsy:
less invasive but less tissu
often initial proceedure of CHOICE, esp if sarcoidosis, infec suspected
- Thoracoscopy
- open lung biopsy
Complications of ILD
- pulm HTN - Cor Pulmonale (R ventricular hypertrophy) - R hrt failure:
jvd, hepatomegaly, pedal edema (peripheral= R sided HF) - pneumothorax (collapsed lung)
- high CA risk
-progr resp insufficiency
Cardiac blood flow to L V is from
LUNGS:
from lungs to LV - to Aorta - to tissues to RA/RV - to pulm arteries (r and l) - to lungs
If blood backs up in LV - back up to lung and get pulm edema
If blood backs up in RV - back up to tissues and get periph edema
ILD overview
Inflammations -> fibrosis (scarred lung tissues)
Sx: DOE, dry cough
CXR: bilat opacities, reticular most common
PFT: can’t expand: restrictive - decreased TLC but ratio normal
DLCO low
Hypoxemia, Resp Alkalosis (low Pco2)
ILD classes
Known cause: occupational and envir exposures: inorganic dust (asbestos, silica, hard metals) organic dust (bacreria, animal proteins0 gases, fumes
Drugs and poisons
- chemo med
- ABx: macrobid (rare)
- radiation CA tx
Infections
IDL classes
Dur to known dz: Sarcordosis CT or autoimm dz: - scleroderma -SLE, RA -Polymyositis/Derma.... -Syst Vasculitis
ILD due to unknown/idiopathic cause:
Idio Interstitial pneumonias (PNA)
Idio Pulm Fibrosis (IPF)
PneumoCONIOSIS
any dz of resp tract due to inhalation of dust particles:
ASBESTOSIS, SILICOSIS
ASBESTOSIS
M>F
occupation hx: construction, plumbers, welders, janitor, shipyard, auto mechanics
linked to cancer and mal mesothelioma: smoking greatly increasis risk
Mesothelioma
Ca ass’d with ASBESTOS exposure:
may be short term 1-2 yrs
CA in mesothelium (protective lingin that covers most organs)
MOST COMMON IN PLEURA (lining of lungs and chest)
can occur in peritonium or pericardium
NOT CAUSED BY SMOKING
poor prognosis and rare
PE of Asbestosis
No spec sx
insidious sudden onset - SOB, reduced exc tolerance
usu DRY cough
insp crackler
DIGITAL CLUBBING (40%) - no severity correlation
Asbestosis dx studies
CXR - opacities in LOWER lungs, thickened pleura and plaques
(HX, PE, SX AND CXR -> suggest Dx)
Open lung biopsy - definite dx but not indicated
histology will show fibrosis and asbestos through microscope
ASbestosis PFTs
Restrictive: can’t inhale :
decreased TLC
decrease FEV1
normal ratio
