journal on ILD

1. TOPIC FOR JOURNAL PRESENTATION-IMAGING OF INTERSTIAL
LUNG DISEASE
NAME OF PRESENTER-DR MIRAZUL HAQUE(2nd YEAR PGT)
DEPARTMENT OF RADIOLOGY, SMCH

2. INTRODUCTION

3. TERMINOLOGY
• Interstial lung disease (ILD): umbrella term –diseases predominantly
involving the pulmonary interstium( rather than alveoli/airways).
• Idiopathic interstial pneumonia (IIP): after exclusion of known causes
( connective tissue disease, drug- induced etc).
• Diffuse lung disease: ILD, small airways disease, alveolar disease ,
thromboembolic

4. • This new ATS-ERS classification is the
result of a multidisciplinary
consensus and includes seven
disease entities: idiopathic
pulmonary fibrosis (IPF), nonspecific
interstitial pneumonia (NSIP),
cryptogenic organizing pneumonia
(COP), respiratory bronchiolitis–
associated interstitial lung disease
(RB-ILD), desquamative interstitial
pneumonia (DIP), lymphoid
interstitial pneumonia (LIP), and
acute interstitial pneumonia (A

7. IDIOPATHIC PULMONARY FIBROSIS
• IPF is the most common entity of the IIPs.
• By definition, IPF is the term for the clinical syndrome associated with
the morphologic pattern of UIP . With a median survival time ranging
from 2 to 4 years, IPF has a substantially poorer prognosis than NSIP,
COP, RB-ILD, DIP, and LIP .

8. CLINICAL FEATURES
• Patients typically present with progressive dyspnoea on exertion and
chronic dry cough, usually over a period of 24 months before
diagnosis. Other associated features might include chest pain, fatigue,
malaise, and weight loss.
• Physical examination usually reveals fine end-inspiratory crackles and
in severe cases finger clubbing.
• Pulmonary function test results may be normal in mild disease or
show restriction pattern (i.e. reduced vital capacity and total lung
capacity but near normal residual volume). Lung function tests show
a restrictive pattern with a decreased diffusing capacity of the lungs
for carbon monoxide (DLCO).

9. Pathology
• IPF, as the name states, is idiopathic, however, there is an association
with concurrent or previous history of smoking in 60% of patients and
genetic factors. Up to 5–20% of patients with IPF have a family history
of interstitial lung disease (ILD) or pulmonary fibrosis. More recently it
has been shown that fibroblasts in this process demonstrate
neoplastic or neoproliferative characteristics

10. HISTOLOGIC FEATURES
• The histologic hallmark of UIP is the
presence of scattered fibroblastic foci
. Typically, the lung involvement is
heterogeneous and areas of normal
lung alternate with interstitial
inflammation and honeycombing

11. Radiographic features
• The chest radiograph is normal in most patients with early disease.
• In advanced disease, the chest radiograph shows decreased lung
volumes and subpleural reticular opacities that increase from the
apex to the bases of the lungs .
• This apicobasal gradient is even better seen on high-resolution CT
images. Together with subpleural reticular opacities and macrocystic
honeycombing combined with traction bronchiectasis, the
apicobasal gradient represents a trio of signs that is highly suggestive
of UIP .

12. • Therefore, UIP should be considered in patients who present with low
lung volumes, subpleural reticular opacities, macrocystic
honeycombing, and traction bronchiectasis, the extent of which
increases from the apex to the bases of the lungs

15. USUAL INTERSTITIAL PNEUMONIA CLASSIFICATION
• Three level of diagonostic certainity
• Inconsistent with UIP
• Probable UIP
• Definite UIP
• Presence of any of the inconsistent features makes the disease
“inconsistent with UIP”
• Presence of all the typical features is needed to diagnose “definite
UIP”
• Presence of a few, but not all typical features, in absence of
inconsistent features: “probable UIP”

17. USUAL INTERSTITIAL PNEUMONIA
 INCONSISTENT FEATURES
• Upper or mid zone predominace
• Peribronchovascular predomince
• Extensive GGO(>reticular opacities)
• Discrete cysts(multiple,bilateral
and away from areas of
honeycombing
• Diffuse mosaic
attenuation(bilateral &3 or more
lobes)
• Segmental/lobar consolidation
 TYPICAL FEATURES
• Subpleural basal predominace
• Reticular lesions
• Honeycombing with or without
traction bronchiectasis
• Absence of inconsistent findings

21. HRCT CRITERIA ALTERNATIVE DIAGNOSIS
CT FEATURES
• Cysts
• Marked mosaic attenuation
• Predominant GGO
• Profuse micronodules
• Centrilobular nodules
• Nodules
• consolidation
Predominat distribution
• Peribronchovascular
• Perilymphatic
• Upper or mid-lung
Other
• Pleural plaques (asbestosis)
• Dilated oesophagus (CTD)
• Extensive LN enlargement(consider
other etiologies)
• Pleural effusions/pl. thickening
(CTD/Drugs)

22. Non-specific interstitial pneumonia
• Second most common morphological and pathological pattern
of interstitial lung diseases
Clinical Features:
• The typical patient with NSIP is between 40 and 50 years old and is usually
about a decade
• younger than the patient with IPF.
• Symptoms of NSIP are similar to those of IPF but usually milder
• Patients present with gradually worsening dyspnea over several months,
and they often experience fatigue and weight loss.
• There is no gender predilection, and cigarette smoking is not an obvious
risk factor in the development of NSIP.

23. HISTOLOGIC FEATURES
• The histologic pattern of NSIP is characterized by temporally and
spatially homogeneous lung involvement.
• This homogeneity is a key feature in differentiating the NSIP pattern
from the UIP pattern.
• On the basis of the varying proportions of inflammation and fibrosis,
NSIP is divided into cellular and fibrosing subtypes .
• In cellular NSIP, the thickening of alveolar septa is primarily caused by
inflammatory cells; in fibrosing NSIP, interstitial fibrosis is seen in
addition to mild inflammation.

25. IMAGING FEATURES
• The most common manifestation consists of patchy ground-glass opacities
combined with irregular linear or reticular opacities and scattered
micronodules
• Subpleural, may be peribronchovascular
• symmetric distribution
• Without any obvious gradient
• In advanced disease:
 Traction bronchiectasis and consolidation, subpleural cysts(microcytic honeycombing )
which are smaller and limited in extent
 Areas of ground-glass attenuation associated with traction bronchiectasis and
bronchiolectasis represents fibrosis .

32. CRYPTOGENIC ORGANIZING PNEUMONIA
• COP is an IIP with characteristic clinical and radiologic features.
• The histologic pattern of COP is organizing pneumonia, formerly
referred to as bronchiolitis obliterans organizing pneumonia (BOOP).
The term BOOP has been omitted to avoid confusion with airway
diseases such as constrictive bronchiolitis

33. CLINICAL FEATURES
• The typical patient with COP has a mean age of 55 years.
• Women and men are equally affected and present with mild dyspnea,
cough, and fever that have been developing over a few weeks
• There is no association with cigarette smoking; in fact, most patients
are nonsmokers or ex-smokers .
• The majority of patients recover completely after administration of
corticosteroids, but relapses occur frequently within 3 months after
corticosteroid therapy is reduced or stopped

34. HISTOLOGIC FEATURES
• The histologic hallmark of
organizing pneumonia is the
presence of granulation tissue
polyps in the alveolar ducts and
alveoli .
• These fibroblast proliferations
result from organization of
inflammatory intraalveolar
exudates .
• Typically, there is patchy lung
involvement with preservation of
lung architecture

35. IMAGING FEATURES
• Patchy consolidation with a predominantly subpleural and/or
peribronchial distribution
• Typically, the appearance of the lung opacities varies from ground
glass to consolidation; in the latter, air bronchograms and mild
cylindrical bronchial dilatation are a common finding
• These opacities have a tendency to migrate, changing location and
size, even without treatment They are of variable size, ranging from a
few centimeters to an entire lobe.
• Atypical imaging findings include irregular linear opacities, solitary
focal lesions that resemble lung cancer, or multiple nodules that may
cavitate

40. SMOKING RELATED IIP
1. Respiratory Bronchiolitis–ILD
• Diffuse centrilobular nodules,
• Ground glass opacities
• bronchial wall thickening
• upper lung predominance
2. Desquamative Interstitial Pneumonia
• Diffuse Ground glass opacities
• Peripheral and Lower lung lobe predominace
• Irregular linear opacities and small cystic spaces

41. Respiratory Bronchiolitis–associated Interstitial
Lung Disease
• Most common smoking-related lung injury. It is called RB-ILD only when
the patient is symptomatic or there are associated physiological
abnormalities
• Upper lobar distribution
• Poor defined centrilobular nodules,patchy GGOs, lobular air trapping,
bronchial wall thickening and emphysematous changes
• Similar appearance in non-smoker: subcute HP
 HP aslo has more widespread and diffuse presence of centrilobular
nodules
Similar appearnaces in lower : DIP
• DIP also has more extensive GGOs and leeser centrilobular nodules

42. CLINICAL FEATURES
• Patients with RB-ILD are usually 30–40 years old and have an average
smoking history of 30 pack-years .
• Men are affected nearly twice as often as women and present with
mild dyspnea and cough.
• Smoking cessation is the most important component in the
therapeutic management of RB-ILD

43. Histologic Features
• The histopathologic hallmark of
RB-ILD is the intraluminal
accumulation of pigmented
macrophages centered around
the respiratory bronchioles. Mild
peribronchiolar inflammation
and fibrosis are usually present

44. Imaging Features
• RB-ILD has an upper lung predominance
• Poor defined centrilobular nodules,patchy GGOs, lobular air trapping,
bronchial wall thickening and emphysematous changes

47. DESQUAMATIVE INTERSTITIAL PNEUMONIA
• More severe form of smoking related ILD
• However, DIP also occurs in nonsmokers and has been related to a
variety of conditions, including lung infections and exposure to organic
dust.
Clinical Features:
• For the majority of patients with DIP, the onset of symptoms is between
30 and 40 years of age.
• Men are affected about twice as often as women, and most patients are
current or past smokers (average smoking history of 18 pack-years).
• With smoking cessation and corticosteroid therapy, the prognosis is
good.

48. HISTOLOGIC FEATURES
• Accumulation of pigmented
macrophages and a few
desquamated alveolar epithelial
cells in the alveoli
• Mild interstitial fibrosis is
present

49. IMAGING FEATURES
• GGO predominant pattern
 don’t diagnose in absence of GGOs
• Lower lobe predomince: subpleural> random distribution
• Air filled cysts can be seen within GGOs
• Peipheral reticular opacities are frequent,but honeycombing is seen
in less than 1/3rd patients
• progresses fibrotic NSIP

52. LYMPHOID INTERSTITIAL PNEUMONIA
• Benign lymphoproliferative condition, associated with AIDS and
Sjogren syndrome
• LIP is only rarely idiopathic
Clinical Features:
• LIP is more common in women than in men, and patients are usually
in their fifth decade of life at presentation.
• They present with slowly progressive dyspnea and cough over a
period of 3 or more years . Occasionally, patients report systemic
symptoms, such as fever, night sweats, and weight loss

53. HISTOLOGIC FEATURES
• The LIP pattern is characterized by
diffuse infiltration of the interstitium
by lymphocytes, plasma cells, and
histiocytes
• Reactive lymphoid follicles are often
present and distributed along the
peribronchiolar regions, which are
highly inflamed

54. IMAGING FEATURES
• Lower lobe predomince
• Thin walled variable sized (1mm -3cm) cysts in peribronchovascular
distribution are characteristic
• Other findings: GGOs, variable sized nodules,interlobular septal
thickening
• With treatment, GGOs resolve but cysts persist.

56. ACUTE INTERSTITIAL PNEUMONIA
• AIP is the only entity among the IIPs with acute onset of symptoms
• Sick patient with rapidly progressive hypoxia with high mortality
Pathology:
• AIP is characterised histologically by diffuse alveolar damage (DAD) and is
indistinguishable from adult respiratory distress syndrome (ARDS). The alveolar
damage comprises three phases:
• an acute exudative phase
• a subsequent organising phase
• a final fibrotic phase

57. IMAGING FEATURES
Plain radiograph
• Nonspecific and often shows bilateral patchy airspace opacification
CT
• During the initial stages, AIP can have features similar to adult respiratory distress
syndrome (ARDS) which include:
• Areas with ground-glass attenuation: bilateral and symmetrical.
• traction bronchiectasis: can be seen in ~80% of cases during the course of the
disease and correlates with disease duration
• parenchymal architectural distortion of the lung
• air space consolidation: may have a slight predilection towards the dependant
portions.

58. CLINICAL FEATURES
• Patients who present with AIP have a mean age of 50 years .
• Most patients develop severe dyspnea with a need for mechanical
ventilation within less than 3 weeks .
• Typically, a history of viral-like illness exists.
• Men and women are equally affected, and cigarette smoking does not
seem to increase the risk for development of AIP.
• Treatment is largely supportive and consists of oxygen
supplementation. Corticosteroids seem to be effective in the early
phase of disease

60. CONCLUSIONS
• CT is the modality of choice in evaluation of ILD
• Recognition of typical imaging patterns and constellation of findings give
probable diagnosis
• HRCT provide reasonable diagnostic advantage to the clinician(without
biopsy)
• A multidisciplinary approach is helpful in most of cases in deciding optimal
management
• IIPs are associated with typical morphologic patterns. The CT appearances
of UIP and COP may be diagnostic in the appropriate clinical context.
However, there is substantial overlap in the CT appearances of the other
IIPs. Therefore, accurate diagnosis of these disorders requires a dynamic
interdisciplinary approach that correlates clinical, radiologic, and
pathologic features.

61. THANK YOU