Role of hrct in interstitial lung diseases pk , This is best powerpoint slides presentation including Latest American thoracic society and fleishners society guidelines . this includes radiographic images a well HRCT chest findings of various ILD. This will help alot for md pg radiology resident and radiologist. Thanks

1. Role of HRCT in Interstitial
lung diseases
Dr Pradeep Kumar
MD Radiodiagnosis

2. HRCT anatomy of the lung.
 HRCT demonstrate the normal anatomy
of the secondary pulmonary lobule(Reid
Lobule).
 SPL is defined as the smallest unit of lung
separated by connective tissue septa.
 Polyhedral in shape measuring 10-30mm
on each side.
 Made up of 3-12 acini and supplied by 3-5
terminal bronchi
 Centrally terminal bronchiole in center
with centrilobular artery.
 Peripherally pulmonary vein and
lymphatic in interlobular septa.
 2 lymphatic networks- central network
that runs along the bronchovascular
bundle towards the centre of the lobule
and a peripheral network that is located
in the interlobular septa and along the
pleural linings.

3. Pulmonary Interstitium
1. Central (axial ) interstitium /peribronchovascular-
bronchovascular sheaths and lymphatics
2. Centrilobular interstitium-connective tissues
surrounding the centrilobular artery and
bronchiole.
3. Peripheral /subpleural interstitium-
pleura,subpleural connective tissues,interlobular
septa with pulmonary veins and lymphatics
4. Intralobular/parenchymal /alveolar interstitium-
alveolar wall(interalveolar septum)
Interstitium of lung is a structural framework of the lung through which course the blood vessels
and airways. It begins at the lung hilum and extends peripherally to the visceral pleura. The
interstitium is divided into following interconnecting spaces:

4. Normal HRCT appearances

6. Approach to HRCT
What is the dominant HR-pattern:
reticular
nodular
high attenuation (ground-glass, consolidation)
low attenuation (emphysema, cystic, honey
combing)
Where is it located within the secondary lobule
(centrilobular, perilymphatic or random)
Is there an upper versus lower zone or a central
versus peripheral predominance
Are there additional findings (pleural fluid,
lymphadenopathy, traction bronchiectasis).

7. Abnormal Patterns in HRCT
Increased Attenuation
Linear and Reticular
Nodular
Ground glass
Consolidation
Decreased attenuation
Emphysema
Lung Cyst
Bronchiectasis
Honey combing
Mosaic Attenuation

8. Linear and reticular opacities
• Due to thickening of
interlobular septa.
Classified into
• Smooth septal
thickening
• Irregular septal
thickening
• Nodular septal
thickening

9. Linear and reticular opacities
Smooth septal thickening
pulmonary edema, hemorrhage,
lymphatic spread of carcinoma, and
amyloidosis;
less common causes include
lymphoma, leukemia,
Churg-Strauss syndrome,
acute lung rejection,
lymphangiectasia, and
metabolic storage diseases such as
Niemann-Pick and Gaucher diseases.

10. Linear and reticular oapcities
Irregular septal thickening
• Irregular if accompanied by
parenchymal distortion –
interstitial pulmonary fibrosis.
Nodular or beaded
• Beaded septum sign
• sarcoidosis,
• lymphangitic carcinomatosis
• amyloidosis and
• occasionally silicosis

13. Nodular opacities
Multiple round
opacities ranging
from 1-10 mm
Distribution of
nodules is most
important factor in
making an accurate
diagnosis in nodular
pattern.
Distribution:
Centrilobular
Perilymphatic
Random

14. Nodular opacities
• Centrilobular:
• Located within center of SPL- several
mm away from pleura; fissure and
interlobular septa
• May appear ill defined ground glass
density; tree in bud.
• Tree in Bud:
• bronchiolitis, bronchopneumonia, and
endobronchial spread
• GG nodules:
• extrinsic allergic alveolitis
• respiratory bronchiolitis,
• cryptogenic organizing pneumonia
(COP)- rare.

15. Nodular Opacities
Perilymphatic nodules-
Nodules are seen in relation to pleural surfaces,
interlobular septa and peribronchovascular distribution
sarcoidosis,
lymphangitic carcinomatosis,
silicosis, and coal worker's
pneumoconiosis
Random
Hematogenous metastases
Miliary tuberculosis
Miliary fungal infections
Sarcoidosis (extensive)
Langerhans cell histiocytosis (early)

16. DISEASES WITH PREDOMINANTLY RETICULAR
PATTERN
• Sarcoidosis
• Lymphangitic carcinomatosis
• Idiopathic interstitial pneumonias
• Fibrosis associated with collagen vascular disease
• Asbestosis
• Drug induced fibrosis.

17. 1.Sarcoidosis
Systemic disease of unknown etiology
Non caseating granuloma
Lung manifestations -90%
Intrathoracic LN – 75-80%
Löfgren's syndrome-an acute presentation
arthritis, erythema nodosum, bilateral hilar adenopathy (9-
34% of patients).
Stages: Chest films in sarcoidosis have been classified into four
stages:
Stage 1- Bilateral hilar lymphadenopathy
Stage 2- Bilateral hilar lymphadenopath + pulmonary disease
Stage 3- Only pulmonary disease
Stage 4- Irreversible fibrosis

18. HRCT findings in Sarcoidosis.
Common findings:
Small nodules in a perilymphatic
distribution
Upper and middle zone predominance.
Lymphadenopathy ( Discrete) bilateral
hila and paratracheal.Often with
calcifications- egg shell.
Uncommon findings:
Conglomerate masses in a perihilar
location.
Larger nodules (> 1cm in diameter, in <
20%)
Grouped nodules or coalescent
nodlues surrounded by multiple
satellite nodules (Galaxy sign)
Nodules so small and dense that they
appear as ground glass or even as
consolidations (alveolar sarcoidosis)

19. Fibrosis in Sarcoidosis
• Progressive fibrosis in sarcoidosis
may lead to peribronchovascular
(perihilar) conglomerate masses of
fibrous tissue.
• The typical location is posteriorly in
the upper lobes, leading to volume
loss of the upper lobes with
displacement of the interlobar
fissure.
• Other diseases that commonly
result in this appearance are:
• Silicosis
• Tuberculosis
• Talcosis

20. 2.Lymphangitis Carcinomatosis
• Results from the hematogenous spread to the lung
with subsequent invasion of the interstitium and
lymphatics in a patient with known malignancy.
• Seen in carcinoma of lung, breast, stomach, pancreas,
prostate, cervix, thyroid.

21. HRCT findings:
-Interlobular septal thickening, thickening
of fissures and thickening of
peribronchovascular interstitium. Septal
thickening may be smooth(fluid) or
irregular(tumor).
-Focal or unilateral abnormalities in 50%
pts.
-Hilar lymphadenopathy in 50% pts.
-Pleural effusion due to pleural
carcinomatosis(>50% pts).
-One of the most characteristic finding-
Polygons with central dots.

22. Idiopathic Interstitial Pneumonias
Also are group of diseases with predominantly reticular or linear pattern
of opacities. Most common in the group is known as Idiopathic
Pulmonary Fibrosis.
In the past, the lack of standarised international classification resulted in
variable and confusin diagnostic criteria and terminology.
An international consensus statement defining the clinical, pathology and
radiological features of patients with IIP was adopted by American
throracic society and European Respiratory society in 2001. Revised in
2013.
The ATS/ERS classification classified it into 7 categories.

23. Idiopathic interstitial
Pneumonia
Idiopathic
Pulmonary
Fibrosis
Idiopathic Interstitital
Pneumonia other than
IPF
Desquamati
ve
Interstitial
Pneumonia
Acute
interstitial
Pneumonia
Non specific
interstitial
Pneumonia
Respiratory
bronchiolitis
interstitial lung
disease
Cryptogenic organising
Pneumonia
Lymphoid
Interstitial
Pneumonia

24. REVISED AMERICAN THORACIC SOCIETY/EUROPEAN RESPIRATORY
SOCIETY CLASSIFICATION OF IDIOPATHIC INTERSTITIAL
PNEUMONIAS: MULTIDISCIPLINARY DIAGNOSES (2013)
Major idiopathic interstitial pneumonias
Idiopathic pulmonary fibrosis (IPF/UIP)
Idiopathic nonspecific interstitial pneumonia (NSIP)
Respiratory bronchiolitis–interstitial lung disease (RB-IP)
Desquamative interstitial pneumonia (DIP)
Cryptogenic organizing pneumonia (COP)
Acute interstitial pneumonia (AIP)
Rare idiopathic interstitial pneumonias
Idiopathic lymphoid interstitial pneumonia (LIP)
Idiopathic pleuroparenchymal fibroelastosis
Unclassifiable idiopathic interstitial pneumonias

25. Idiopathic Interstitial Fibrosis
(Idiopathic Pulmonary Fibrosis)
Most common
It is the term used for clinical syndrome associated with
morphological pattern of UIP.
Clinically-
M>F ( slightly), usually older than 50 years, smoker.
Progressive dyspnea , cough, F/O right heart failure
Median survival time after diagnosis- 2.5-3.5 years.

26. • Histologically- scattered
fibroblastic foci, heterogenous lung
involvement. Patchy lung
involvement ( hence HRCT needed
for biopsy samples).
Plain radiograph-
 Low lung
volumes,
coarse
reticular
opacities,
honeycombing
 Basal
predominance

27. HRCT-
Bilateral , patchy, subpleural ,
basilar reticular opacities
Presence of apicobasal gradient
Associated with architectural
distortion, honeycombing and
traction bronchiectasis.
GGO may be seen, less
prominent than reticular
opacities.

29. Levels of certainty with HRCT
Diagnostic features of UIP-
Reticular opacities and traction
bronchiectasis
Honeycombing ( critical for diagnosis)
Subpleural and basal distribution
Architectural distortion from lung
fibrosis
Absence of inconsistent features.
Heterogenous area with regions of
fibrotic lung alternating with normal
lung
UIP pattern in HRCT correlates with
UIP pattern at surgical lung biopsy
Inconsistent features
Upper or mid lung predominance
Peribronchovascular predominance
Extensive ground glass
Multiple micronodules
Discrete cysts
Consolidation
Mosaic attenuation
Possible UIP
Reticular opacities often associated with traction
bronchiectasis.
Distribution subpleural and basal
Absence of inconsistent features
Absence of honeycombing.

31. Nonspecific Interstitial
Pneumonias
Very good prognosis and responds well to steroid treatment.
Although called idiopathic, morphological pattern is associated with patterns in
connective tissue disorders, drug induced pneumonitis, hypersensetive
pneumonitis, infection and immunodificiency. Once the pattern of NSIP has
been determined, secondary forms of NSIP should be excluded out by clinician.
Clinical-
F>M, smokers and nonsmokers both, 40-50 years ( decade younger than patients
with UIP)
Dyspnea, cough and weight loss

32. • Histologically-
Temporally and
histologically homogenous
lung involvement ( key
differentiating feature
from UIP)
 Xray-
Initially normal, later Reticular
opacities in lower lobes without
honeycombing
No apicobasal gradient

33. HRCT-
Bilateral , predominantly lower lobes, subpleural,
symmetricity.
Traction bronchiectasis
Volume loss
No honeycombing or microcystic honeycombing (
in comparision to macrocystic honeycombing in
UIP)
Ground Glass opacities are the predominant
feature (50% cases).
 Prognosis – Good
 Steroid responsive
 5 year mortality rate <18 percent.

34. Comparision- UIP vs NSIP

35. Cryptogenic Organising pneumonia
Previously called Bronchiolitis Obliterans Organizing Pneumonia (BOOP).
A non specific inflammatory response by the lung to various forms of injury.
Inflammatory process where the healing process is characterized by the
organization of the exudate rather than by resorption( unresolved pneumonia).
Clinical-
Mild SOB, fever, cough, chills, weight loss, myalgia.
Most are non smokers and most respond to steroids.
male= females, onset: 55yrs.
Most patients report respiratory tract infection preceeding the illness.
• As with other interstitial pneumonias, pattern may occur in a wide variety of
entities, notably collagen vascular disease, infectios, hence final diagnosis should be
rendered only after exlusion of differntials.

36. • Histopathology-
granulation tissue polyps in
alveolar ducts/ alveeoli
CXR-
Unilateral or bilateral patchy
consolidation that resembles
pneumonic infiltrates.
Lung volumes usually preserved.

37. HRCT
CT findings more extensive than expected from Xray
Characteristic peripheral and peribronchial distribution
Lower lung lobes more involved.
In some cases, outermost subpleural areas spared.
Lung opacities range from GGO to consolidation.
Opacities have tendency to migrate with change in
location and shape even without treatment.
In appropriate clinical setting, consolidation that
increases over several weeks despite antibiotics may be
suggestive.
Reverse halo sign- specific finding in COP. (20% cases)
Crazy paving pattern ( infrequent).
Atypical findings include- irregular linear opacities,
solitary focal lesions, multiple nodules with cavitations.

39. Respiratory bronchiolitis related interstitial
lung disease (RB-ILD)
Very small percentage of typically young heavy smokers.
exclusively in current or former cigarette smokers
30 to 40 years old
male-to-female ratio of 2:1.
Symptomatic with decreased diffusing capacity.
RB-ILD have good prognosis following smoking cessation.
No arbitrary cut off between RB and RB-ILD on HRCT.
Chest radiographic -thickening of the walls of the central and
peripheral bronchi and diffuse bilateral reticulonodular opacities.
normal in 20% of patients

40. HRCT- RB-ILD
• Small centrilobular ground-glass
nodules, patchy GGO, and
bronchial wall thickening - the
most common finding on HRCT, but
fine centrilobular nodules may also
be seen.
• Although emphysematous changes
may be present, subpleural
honeycombing and traction
bronchiectasis are absent.

41. Desquamative interstitial
pneumonia
Rare , strongly associated with cigarette
smoking.
Clinical- 30-40 years, male , smoker, average
smoking
Clin/path/rad distinction between RBILD and
DIP blurred but 6-30% mortality
Ground glass more extensive and diffuse as
compared to RB-ILD, may be subpleural and
basal. Centrilobular nodules uncommon.
Mid and lower lungs predominately involved
with a peripheral predilection.
–/+ reticulation, cysts, emphysema

42. Acute Interstitial Pneumonias
Only entity in IIP with acute onset of
symptoms.
Rapidly progressive interstitial pneumonia
with poor prognosis
Histologically – diffuse alveolar damage,
hyaline membrane formation and
indistinguishable from ARDS.
Clinical-
Mean age – 50 years, M=F.
Preceeding flu like illness followed by rapidly
progressive dyspnea in few weeks.

46. Ground Glass opacity
hazy increased attenuation of lung with preservation of bronchial and
vascular markings.
seen with HRCT while plain films are still negative
Filling of the alveolar spaces with pus, edema, hemorrhage, inflammatory
or tumor cells.
Thickening of the interstitium or alveolar walls below the spatial resolution
of the HRCT seen in fibrosis.
Hence, GGO can be from both airspace and interstitial lung disease

47. •The location of the
abnormalities in ground glass
pattern can be helpfull:
• Upper zone predominance:
Respiratory bronchiolitis, PCP.
• Lower zone predominance:
UIP, NSIP, DIP.
• Centrilobular distribution:
Hypersensitivity pneumonitis,
Respiratory bronchiolitis

48. Ground Glass Attenuation
Pattern
Ground glass pattern is non specific, occurs in several
disease process . In most instances represents active,
potentially reversible or treatable process .
Many ILD demonstrate GGO intersepted with other
patterns . These areas are likely to represent active
alveolitis or active parenchymal disease .
ILD with predominantly GGOs are-
Hypersensetivity Pneumonitis
Acute interstitial pneumonitis
Desquamative interstitial Pneumonitis
Pulmonary Alveolar proteinosis.

49. Alveolar Proteinosis
Rare disease , no cause known.
Characterized by filling of the alveolar spaces with
proteineous material, probably dueto excessive
production or impaired removal of surfactant.
Material is positive on PAS staining.
Clinical-
30-50 years, Male predominance
Chest xray –
Characteristic bilateral, bat wing like pattern,
resembling CCF, but without kerley B lines or
cardiomegaly.
The diagnosis is based on the suggestive HRCT
pattern (crazy paving), geographic distribution with
sharp demarcation of normal and abnormal areas,
and the characteristic features of BAL fluid (Broncho
Alveolar Lavage)
Crazy paving pattern: reticular pattern
superimposed on ground glass opacification

50. Consolidation• Increased lung density (opacification
with obscuration of bronchovascular
marking) due to replacement of air in
alveoli by fluid, blood or cells.
Occassionally by interstitial disease
(alveolar sarcoidosis).
• Air bronchogram
• bacterial and fungal pneumonia,
• ARDS, heart failure
• COP,
• hypersensitivity pneumonitis.

53. Pneumoconiosis
• Specific patient group (construction workers, mining
workers, workers exposed to sandblasting, glass
blowing and pottery).

54. Common Pneumoconiosis

55. Silicosis

56. Simple silicosis

57. Complicated silicosis
Appearance of one or more areas where silicotic
nodules have become confluent( >1 cm in
diameter) .
Associated with symptoms , often with
disability.
CXR
Opacities in middle zone or in the periphery of
lung in upper lobes. Tend to migrate to hilum ,
leaving overinflated emphysematous lung tissue
in surrounding lung.
As conglomeration develop, lungs loose volume,
cavitation of mass occurs via necrosis.
TB infection , Atypical Mycobacteria may
supervene , but difficult to detect (
microbiologic confirmation required).
HRCT- similar findings, earlier detection.

58. Acute silicosis-
Occurs due to exposure of large quantities of fine
particulate silica in enclosed spaces over a period of
few weeks. Rapidly progressive disease with death
due to respiratory failure.
Radiological features- bilateral diffuse consolidation
or airspace opacification in perihilar distribution .
Pathologically the alveoli are filled with PAS positive
material
( Radiologically and pathologically resembles Alveolar
Proteinosis)

59. Caplan syndrome-
Silicosis associated with several
connective tissue diseases-
Progressive systemic sclerosis,
Rheumatoid arthritis, SLE.
Consists- Large necrobiotic nodules (
rheumatoid nodules) , superimposed
on background of simple silicosis or
coal worker pneumoconiosis . M/C in
Coal worker pneumoconiosis .
Nodules are 0.5-5 cm , may cavitate.

60. Coal worker Pneumoconiosis
• Underground
miners.
• Pathologically,
hallmark is coal
macule.

61. Simple Coal worker pneumoconiosis
CXR- nodules , predominantly in upper
lobes. In contrast to silicosis, after
exposure to coal dust subsides, no
progression of coal worker
pneumoconiosis.
HRCT-
 parenchymal or subpleural nodules ( <7
mm), upper zone, right sided
predominance.
When confluent, form pseudoplaques,
which are subplerual foci linear areas of
increased attenuation that are less than 7
mm wide.

62. Complicated Coal worker
pneumoconiosis
• A/K/A progressive massive
fibrosis
• Opacities identical to
silicosis( upper lobe
predominance, single
opacity is more than 1 cm
in size, may cavitate.
• Coal worker
pneumoconiosis is usually
associated with
emphysema.

63. Hypersensitive pneumonitis
Due to inhalation of wide array of antigens,
incite immunopathological reaction, A/K/A-
Extrinsic allergic alveolitis.
Includes- Farmers lung, bird fanciers lung,
mushroom workers lung, bagassosis etc.
3 clinicopathological types- acute ( occurs
within 4-6 hrs ), subacute ( weeks to months of
exposure ), chronic ( follow longterm and low
level exposure )
Characteristic findings- ill defined granulomas,
bronchiolitis and alveolitis.
farmer's lung, bird fancier's lung, 'hot tub'
lung, humidifier lung.
Acute, subacute, and chronic stages.
Mostly HRCT is performed in the subacute
stage or chronic phase

64. HRCT findings-
Vary with stage of disease.
Acute- bilateral consolidation, and
small poorly defined centrilobular
nodules.
Subacute/Chronic- Patchy GGO
intermingled with Ill defined
centrilobular nodules, Mid and lower
zones predominance.
Mosaic attenuation pattern
Head cheese sign- GGO+ normal
attenuation of lung+ decreased
attenuation of lung (air trapping)
Lung cysts ( 10% cases)
Fibrosis , irregular reticular opacities,
honeycombing ( chronic cases).

66. Emphysema
Emphysema typically presents as areas of low attenuation
without visible walls as a result of parenchymal destruction.
• Centrilobular emphysema (Most common type )
Irreversible destruction of alveolar walls in the
centrilobular portion of the lobule
Upper lobe predominance and uneven distribution
Strongly associated with smoking.
Panlobular emphysema
Affects the whole secondary lobule
Lower lobe predominance
In alpha-1-antitrypsin deficiency, but also seen in
smokers with advanced emphysema
Paraseptal emphysema
Adjacent to the pleura and interlobar fissures
Can be isolated phenomenon in young adults, or in
older patients with centrilobular emphysema
Frequently associated with bulla formation.
In young adults often associated with spontaneous
pneumothorax

67. Lung Cysts
• Lucent areas with wall thickness of
less than 4 mm.

68. Honey combing
• Honeycombing is a process
characterized by the presence of
cystic spaces, having thick, clearly
definable fibrous walls lined by
bronchiolar epithelium;
• cystic spaces usually average 1 cm in
diameter and their walls 1 to 3 mm in
thickness.
• End stage lung disease- no
diagnosis by biopsy
• Peripheral and subpleural location;
several contiguous layers

71. Bronchiectasis
Bronchiectasis is defined as localized
bronchial dilatation.
diagnosis is usually based on a
combination of the following findings:
bronchial dilatation (signet-ring sign)
bronchial wall thickening
lack of normal tapering with visibility of
airways in the peripheral lung
mucus retention in the bronchial lumen
associated atelectasis and sometimes air
trapping
Common cause of bronchiectasis are
prior infection, usually viral, at an early age.
( most common)
Tuberculosis
chronic bronchitis,
COPD and
cystic fibrosis.

73. Mosaic attenuation
Density differences between
affected and non-affected lung
areas- patchy areas of black and
white lung.
When ground glass opacity
presents as mosaic attenuation
consider:
Infiltrative process adjacent to normal
lung
Normal lung appearing relatively
dense adjacent to lung with air-
trapping
Hyperperfused lung adjacent to
oligemic lung due to chronic
thromboembolic disease

74.  Which part is abnormal: the black
or the white lung?
If the vessels are difficult to see
in black lung , compared to white
lung, it is likely that black lung is
abnormal. D/D- Chronic
pulmonary embolism, obstructive
bronchiolitis.
If the vessels are similar in both
white and black lung, the disease
is in the white lung, probably an
infiltrative disease, like
pulmonary hemorrhage,
hypersensitivity pneumonitis.
GGO abnormal- Hypersensitivity pneumonitis
Chronic thromboembolic disease

76. Cystic Pattern
• Lymphangioleiomyomatosis
• Langerhan cell histiocytosis.
• Lymphocytic interstitial pneumonitis.

77. lymphangioleiomyomatosis
Rare disease, occurs only in women of reproductive age group. Associated with
tuberous sclerosis.
Progresive proliferation of the atypical muscle cells along the bronchiole leading to air
trapping and the development of the thin walled cysts
Majority present with dyspnea.
Chylous pleural effusion(40%), pneumothorax(40%), hemoptysis(40%).
Patients die within 10 yrs of onset of symptoms.
Pregnanacy may exacerbate the disease.

78. HRCT findings
Numerous thin walled
cysts, surrounded by
normal parenchyma.
Cysts range from 2mm-
5cm, round, uniform.
Wall thickness of cysts
range from barely
perceptible- 4mm. (vs
honeycombing-
subpleural location with
thick wall)
Distributed throughout
lungs.

79. Langerhans cell Histiocytosis
• Langerhan cell histiocytosis represents diverse group of diseases affecting
several organs with different clinical outcomes. Acute dissemenated ( letter siwe
disease) - seen in young children, poor prognosis. Multifocal LCH (Hans- Schuller
– Christian disease)- older children and adoloscents, favourable prognosis.
• In lungs- Probably an allergic reaction to the cigrette smoke. More than 90% are
active smokers.
• In early stage- formation of the granulomatous nodules containing langerhans
histiocytes and eosinophils.
• Later stage granulomas cavitate, are replaced by fibrosis and cysts formation
takes place by coaleaseing cavities.
• Young- middle aged. 20% present with pneumothorax.
• Most cysts are round , but can have bizzare shape( bilobed/clover leaf shaped).
• Upper lobe predominance , sparing of costophrenic angles

80. HRCT findings
Early stage:
-Small irregular or stellate
nodules in centrilobular
location.
Late stage:
-Cystic airspaces <10mm in
diameter with walls barely
perceptible to several mms
thick.
-Bizzare shaped cysts that may
coalese.
-Upper and mid lobe
predominance.
-Recurrent pneumothorax.

81. Lymphangioleiomyomatosis Langerhan cell histiocytosis
Almost exclusively seen in females of reproductive age No such predominance
No association with smoking Associated with smoking
Diffuse lung involvement Upper lobe predominance
Sparing of costophrenic angles

82. Collagen Vascular Disease Associated
Diffuse Lung Disease
• Rheumatoid Arthritis
• Systemic Lupus Erythematosus
• Systemic Sclerosis
• Ankylosing Spondylosis

83. Rheumatoid Arthritis
Most common Collagen vascular disease
M:F- 1: 2-3
 pleuropulmonary abnormalities are associated with RA.
Pleurisy with or without effusion –
 Most common manifestation of RA, Pleural fluid is exudative type
 Typically right sided, typically unilateral
 Unchanged over many years
 Recurrent, occasionally result in fibrothrorax.

84. 2. Interstitial fibrosis and Pneumonitis-
Histopathologically , abnormalities may
take the form of any of the various
Idiopathic Interstitial Pneumonias ( NSIP
being most common), so radiologically
resemble to that of NSIP ( commonly) or
UIP.
3. Necrobiotic nodules-
Are intrapulmonary rheumatoid nodules
( pathologically identical to subcutaneous
nodules )
Uncommon feature, associated with
advanced disease.
Usually nodules are peripherally located ,
cavitation common, walls thick and
smooth.

85. 4. Caplan syndrome
5. Pulmonary vasculitis –
may lead to pulmonary
hypertension . However,
pulmonary hypertension
usually results from end
stage fibrosis.
6. Airway disease-
Bronchiectasis,
obliterative bronchiolitis (
usually related to drugs
used to treat the
condition).
Rheumatoid necrobiotic nodules
4 years later -Necrobiotic nodules increased in size

86. Systemic Lupus Erthematosis
• Multisystem disease; female predominance
• Autoantibodies against nuclear antigens
• Pleuropulmonary disease upto 50%
• Chest involvement:
• Pleurisy and pleuritis- most common
• inflammatory pneumonitis (acute lupus pneumonitis)
• Interstitial pulmonary fibrosis,
• pulmonary hypertension,
• Pericarditis,
• Diaphragmatic dysfunction (“shrinking lung syndrome”), and phrenic nerve
palsy
• Infection is most common complication- upto 50% with
pleuropulmonary disease

87. Systemic Lupus Erthematosis
• Acute lupus pneumonitis -uncommon
life-threatening complication –
• fever, severe hypoxemia, and diffuse
pulmonary infiltrates.
• Usually respond to steroids
• D/D- pulmonary infection or hemorrhage
• Diffuse Alveolar hemmorrhage- fatal
complication
• nonspecific diffuse air space
consolidation
• Crazy paving on HRCT
• Chronic form is not common

88. Systemic Sclerosis
Connective tissue disease characterised by fibrosis and atrophy
of skin, lungs, GI tract , heart and kidneys.
4-6 th decade, F>M.
After esophagus, lung is second most affected visceral organ.
Pulmonary manifestations takes one of 3 forms-
a. Interstitial fibrosis ( M/C)
b. Pulmonary vascular disease
c. Pleural changes.
 Patho- Vascular disease involving capillary bed----
Pulmonary hypertension.
 CXR- Features similar to NSIP( commonly ) or UIP. Pleural
involvement- uncommon.
 HRCT- Features are similar to those described for Rheumatoid
disease ( Features of NSIP or UIP). Except those, non
pulmonary manifestations may be noted – skin and
subcutaneous tissue calcinosis, atony of esophagus.
Bilateral GGO, interlobar,
intralobar septal thickening,
dilated esophagus, subpleural ,
basal distribution.

89. Drug induced lung disease
• A major source of iatrogenic lung injury.
• May present with variety of radiologic patterns.
• Present as organizing pneumonia, eosinophilic pneumonia,
fibrosis, hypersensitivity pneumonitis, or even ARDS.
• Thus usually a diagnosis of exclusion.

94. • Diffuse lung diseases are vast with majority having relatively similar imaging findings
and clinical presentation which often overlap. The guideline developed by ATS and
ERS updated in 2013 is a multidisciplinary diagnosis guideline emphasizing the
importance of multidisciplinary diagnosis (MDD). Adequate presentation and
discussion of clinical and radiological data with histopathological findings are
essential for an accurate MDD. The accurate diagnosis of ILD needs accumulated
experience, especially IIP.

95. Important Revision chart and table

99. CATEGORIZATION OF MAJOR IDIOPATHIC
INTERSTITIAL PNEUMONIAS

101. Primary Disease related
Diffuse Lung Disease
• Sarcoidosis
• Alveolar Proteinosis
• Eosinophilic Lung Disease
• Lymphangioleiomyomatosis

102. According to zonal distribution

103. Associated findings

104. Change in lung volumes

105. Predominant Patterns-

106. THANK YOU