restrictive lungdiseases
DESCRIPTION
This ppt is mainly designed for UG pathology teaching.TRANSCRIPT
Restrictive Diseases
Dr.CSBR.Prasad, M.D.
Chronic restrictive diseases
Restrictive diseases due to chest wall disorders
Restriction due to interstitial and infiltrative
diseases.
Restrictive - chest wall disorder
1. Kyphoscoliosis
2. Ankylosing spondilosis
3. Poliomyelitis
4. Severe obesity
5. Pleural diseases
Interstitial and infiltrative diseases
1. Pneumoconiosis
2. Immunologic lung diseases
3. Collagen vascular diseases
4. Sarcoidosis
Infiltrative - Radiologic term
• Chest radiograph - ground glass shadow
• Diffuse infiltration by nodules/lines
Clinical features
1. Dyspnoea
2. Tachypnoea
3. Cyanosis
4. No wheezing
Pneumoconiosis
• Lung disease caused by inhalation of dust
• Synonyms:
• Dust diseases
• Occupational lung diseases
• Dusts –Inert
Predispose to TB
Predispose to neoplasia
Factors determining - disease
1. Size / shape of particles
2. Solubility
3. Amount of dust retained in lungs
4. Effect of other irritants - ex Smoke
5. Host factors:
Clearance mechanism
Immune status
Size of dust
• Particles larger than 5µm may reach
– Terminal airway
– Ingestion by alveolar macrophage
• Smaller than 1µm may
– Reach alveoli
– Stimulate macrophage
– Result in fibrosis
In the nose, the hair at the external
nares filter out the larger particles,
trapping almost all particles larger than
5µm.
In the trachea and bronchi, 90% of the
particles larger than 3-5µm are caught.
Particles between 0.5 and 2µm reach
the alveolar ducts and alveoli.
Solubility and cytotoxicity
• Smaller particles:
– Pulmonary fluid
– Rapid toxic levels
– Cause acute lung injury
• Larger particles:
– Resist dissolution
– Persist in lung for years
– Evoke fibrosis ex silicosis
Physiochemical reactivity
• Quartz particles
• Direct injury to tissue and cell membrane
• Can trigger proinflammatory / profibrosing
reaction
Systemic response
• Particles reach LN by macrophages
• Initiate immune response / amplifies local
reaction
• Particles translocate to blood
• Evokes systemic inflammation.
Host tissue response
1. Fibrous nodules ex coal workers
pneumoconiosis, silicosis.
2. Interstitial fibrosis ex asbestosis.
3. Hypersensitivity ex.berylliosis.
Pneumoconiosis
(inorganic dusts)
• Coal dust
• Silica
• Asbestose
• Berylium
• Iron oxide
• Simple coal w p
• PMF
• Caplan’s syndrome
• Silicosis
• Caplan’s syndrome
• Asbestosis
• Pleural disease
• Pleural tumors
• Beryliosis
• Pulmonary siderosis
Pneumoconiosis
(biologic dusts)
• Mouldy hay
• Bagasse
• Cotton, flax, hempdust
• Bird droppings
• Mushroom compost dust
• Mouldey barley, malt dust
• Mouldy maple bark
• Silage fermentation
• Farmers’ lung
• Bagassosis
• Byssinosis
• Bird breeders disease
• Mushroom workers lung
• Malt workers lung
• Maple-bark disease
• Silo fillers’ disease
One form of hypersensitivity pneumonitis is known as farmer's lung - the farmer
inhales thermophilic actinomycetes in moldy hay that set off the reaction
"silo filler's disease" which is an acute chemical pneumonitis due to toxic
gases released from fermenting silage into the atmosphere inside the silo
Coal workers’s pneumoconiosis
1. Asymptomatic
2. Simple coal worker’s pneumoconiosis
3. Complicated CWP (progressive CWP)
Complicated CWP [PMF]
• Confluence of fibrosing reaction in lung
that is a complication of any
pneumoconiosis
• Common in CWP
• Can also be seen in silicosis
Anthracosis
• Coal - Innocuous
• Common in urban dwellers/smokers
• Carbon pigment in lung, lymphatics, LN
• Autopsy: linear streaks and aggregates in
pul. lymphatics, LNs
Simple CWP
• Coal macule: 1 to 2 mm, carbon laden macrophages
• Coal nodules: larger than macule, contain delicate collagen fibres
• Upper lobes, upper zones of lower lobes heavily involved
• Located adjacent to resp bronchioles-initial dust deposition site-centrilobular emphysema
Complicated CWP (PMF)
In a background of simple CWP
Over years
Intensely blackened scars
Larger than 2 cms
May be upto 10 cms
Multiple,bilateral,involve upper,post region
Micro: dense collagen, pigment,
necrotic centre,with local ischemia
Caplan syndrome (Rheumatoid pneumoconiosis)
• Development of rheumatoid arthritis in
CWP, silicosis, asbestosis
• Gross; round, firm nodules with central
necrosis, cavitation or calcification
• Micro: central zone of dust laden fibrinoid
necrosis enclosed by palisading
fibroblasts and mononuclear cells
Clinical features
• Cough with jet black sputum
• Dyspnoea
• Pul-HT, cor pulmonale
• TB and RA are more common in miners
• Increased risk for Ca. stomach
• Bronchogenic .ca is rare
Figure 15-18 Progressive massive
fibrosis superimposed on coal
workers' pneumoconiosis. The large,
blackened scars are located
principally in the upper lobe. Note the
extensions of scars into surrounding
parenchyma and retraction of
adjacent pleura.
"coal worker's pneumoconiosis"
Silicosis Knife grinders lung
Silicosis knife grinders lung
• Silica (silicon dioxide)
• Caused by inhalation of crystaline silica
• Presents after decades of exposure
• Slowly progressing nodular, fibrosing
pneumoconiosis
Acute silicosis
• Heavy exposure over months to few years
• Generalized accumulation of
lipoproteinaceous material within alveoli
• Morphologically identical to alveolar
proteinosis.
Chronic silicosis
Characterized by formation of small
collagenous silicotic nodules
Occupations - Silicosis
• Miners
• Quarry workers
• Tunnelers
• Sand blasters
• Grinders
• Ceramic workers
• Foundry workers
• Silica abrasive manufacturers
• Exposure to pencil
• Slate
• Agate grinding
Silica – Physical forms
Crystalline forms
• Quartz
• Crystobalite
• Tridymite
• Are fibrogenic
Amorphous forms
• Talc
• Vermiculite
• Mica
• Less fibrogenic
IARC pointed out that only crystalline form is actually carcinogenic
Pathogenesis - Silicosis
• Silica - macrophage ingestion - direct toxic effect
• Silica particles - activation and release of mediators by viable macrophages
• IL-1, TNF, fibronectin, lipidmediators, oxygen derived free radicles, fibrogenic cytokines
• Mixed with other minerals, quartz has less fibrogenic effect. ex: hematite.
Gross pathology
• Silicotic lung studded with well
circumscribed hard, fibrotic nodules,1 to 5
mm in diameters
• Scattered throughout the lung
• Simultaneous deposition of coal dust with
calcification
• Pleura thickened, adherent to chest wall
• Similar nodules in LN, pleura
Gross pathology contd…,
• X ray nodular lesions - egg shell shadows
• Lesion – necrosis, cavitation
• Complicated by TB, rheumatoid
pneumoconiosis.
Egg shell calcification
FIGURE 15-18
Advanced silicosis
Scarring has contracted
the upper lobe into a
small dark mass (arrow).
Note the dense pleural
thickening.
Microscopy of silicosis
• Nodular lesions- concentric layers of
hyalinised collagen surrounded by dense
capsule of more condensed collagen
• Polarising microscopy --- birefringent silica
particles.
Figure 15-19 Advanced silicosis seen on transection of lung. Scarring has
contracted the upper lobe into a small dark mass (arrow). Note the dense
pleural thickening.
Figure 15-20 Several coalescent collagenous silicotic nodules.
Figure 15-20 Several coalescent collagenous silicotic nodules.
Pneumoconiosis: polarized light microscopy - silica crystals.
Here are seen bright white crystals of varying sizes.
Bright white collections of polarizable crystals are seen here, but are diffuse and centered
around vascular spaces. This is the lung of a patient with a long history of intravenous drug use
Clinical features-silicosis
Asymptomatic- routine chest x ray
X ray- fine nodularity in upper zones
Pulm functions –normal/mildly affected.
Slow to kill but impaired pulm fn severely limits
activity.
Depresses CMI
Increased susceptibility to TB
Crystalline silica - occupational source of
carcinogen.
E N D
Contact:
Dr.CSBR.Prasad, M.D.,
Associate Professor,
Deptt. of Pathology,
Sri Devaraj Urs Medical College,
Kolar-563101,
Karnataka,
INDIA.