Diffuse (interstitial) lung disease includes a wide variety of relatively uncommon conditions presenting with characteristic clusters of clinical features and marked by an immune response. There are over 200 specific diffuse lung diseases, many of unknown etiology. The combined incidence is 50 per 100,000, or 1 in 2000 people. Because these conditions cause aberrant lung function, morbidity and mortality due to lung injury and fibrosis are not uncommon. Both environmental and genetic factors are believed to contribute to the development of diffuse lung disease. Antigen processing and presentation are important in the development of the immune response seen in the disease, and it is thought that the likely candidate genes predisposing patients to this category of disease are those of the major histocompatibility complex. Genes that affect the immune, inflammatory, and fibrotic processes may also influence who develops the disease. If we can identify the genes that cause diseases characterized by lung injury and fibrosis, we can eventually develop genetic interventional approaches to treatment.

1. INTERSTITIAL LUNG DISEASES
Notes by: Dr.Arun Vasireddy

2. DEFINITION
 Encompasses a group of disorders of diverse aetiologies
with common features of varying degrees of fibrosis and
inflammation of the lung parenchyma or interstitium.
 It includes over 200 different diseases which, in spite of their
heterogenous nature have several common clinical,
radiological and histological manifestations.

3. “INTERSTITIAL” – A MISNOMER
• The interstitium of the lung spans the region between the alveolar
epithelial and capillary endothelial basement membranes.
• This region includes a variety of cell types (fibroblasts, myofibroblasts,
and macrophages) and matrix components (collagens, elastin, and
proteoglycans).
• The interstitium extends from the alveolar space proximal to the
terminal and respiratory bronchioles.
 This group of pulmonary disorders frequently involves:
• alveolar epithelium, alveolar space, pulmonary microvasculature,
respiratory bronchioles, larger airways & pleura

4.  ILDs have been difficult to classify because >200 known
individual diseases are characterized by diffuse parenchymal
lung involvement, either as the primary condition or as a
significant part of a multiorgan process, as may occur in the
connective tissue diseases (CTDs).
 ILDs classified into two groups based on the major underlying
histopathology:
1. those associated with predominant inflammation and
fibrosis and
2. those with a predominantly granulomatous reaction in
interstitial or vascular areas
• Each of these groups can be further clinically subdivided
according to known or unknown etiology

7. EPIDEMIOLOGY
 ILDs in India was considered to be rare in the past.
 Increased awareness & wider availability of HRCT and other
diagnostic tests have led to increased recognition.
 ILDs constitute about 10% to 15% of the patients with respiratory
diseases, seen at any large hospital in the country.
 About 50% of the ILDs are idiopathic in origin while others are
associated with identifiable diseases, most commonly, a CTD.
 UIP, also known as IPF is the most common form of IIP.

8. PATHOGENESIS
 ILDs are non-malignant disorders and are not caused by identified
infectious agents.
 The precise pathway(s) leading from injury to fibrosis is not known.
 Although there are multiple initiating agent(s) of injury, the
immunopathogenic responses of lung tissue are limited, & the
mechanisms of repair have common features
 The two major histopathologic patterns
 inflammation and fibrosis
 granulomatous

10. INFLAMMATION & FIBROSIS
 The initial insult is an injury to the epithelial surface causing inflammation in the
air spaces and alveolar walls.
 If the disease becomes chronic, inflammation spreads to adjacent portions of
the interstitium and vasculature and eventually causes interstitial fibrosis.
 Important histopathologic patterns found in the ILDs include UIP, NSIP,
respiratory bronchiolitis, organizing pneumonia (BOOP), diffuse alveolar damage
(acute or organizing), DIP, & lymphocytic interstitial pneumonia.
 The development of irreversible scarring (fibrosis) of alveolar walls, airways, or
vasculature is the most feared outcome in all of these conditions because it is
often progressive and leads to significant derangement of ventilatory function
and gas exchange.

11. CELLULAR BASES FOR THE PATHOGENESIS

12. EPITHELIAL DAMAGE & ACTIVATION
• Multiple microinjuries damage and activate alveolar
epithelial cells, which in turn induce an antifibrinolytic
environment in the alveolar spaces, enhancing wound
clot formation.

13. FIBROBLAST MIGRATION & PROLIFERATION
• Alveolar epithelial cells secrete growth factors and
induce migration and proliferation of fibroblasts and
differentiation into myofibroblasts

14. ANGIOGENISIS & MYOFIBROBLAST FOCI FORMATION
• Subepithelial myofibroblasts and alveolar
epithelial cells produce gelatinases that may
increase basement membrane disruption and
allow fibroblast–myofibroblast migration.
• Angiogenic factors induce neovascularization.

15. FIBROSIS & IMPAIRED REEPITHELIAZATION
• Both intraalveolar and
interstitial myofibroblasts
secrete extracellular matrix
proteins, mainly collagens.
• An imbalance between
interstitial collagenases and
tissue inhibitors of
metalloproteinases provokes
the progressive deposit of
extracellular matrix.
• Myofibroblasts produces angiotensin II provoking
alveolar epithelial cell death, further impairing
reepithelialization.

17. GRANULOMATOUS LUNG DISEASE
 Characterized by an accumulation of T-lymphocytes, macrophages
and epithelioid cells organized into discrete structures
(granulomas) in the lung parenchyma.
 The granulomatous lesions can progress to fibrosis.
 Many patients with granulomatous lung disease remain free of
severe impairment of lung function, or when symptomatic, they
improve after treatment.
 DDx - sarcoidosis and hypersensitivity pneumonitis

18. DIAGNOSING ILD
 A clinical diagnosis is possible for many forms of ILD, especially if
an occupational and environmental history is aggressively
pursued.
 For other forms, tissue examination, usually, obtained by
thoracoscopic lung biopsy, is critical to confirmation of the
diagnosis.
 HRCT scanning improves diagnostic accuracy as experience with
histologic-image correlation is perfected.

19. SIGNS & SYMPTOMS
 Dyspnoea is a common and prominent complaint in patients with
ILD, especially the idiopathic interstitial pneumonias,
hypersensitivity pneumonitis, COP, sarcoidosis & eosinophilic
pneumonias.
 Some patients, especially patients with sarcoidosis, silicosis,
hypersensitivity pneumonitis, lipoid pneumonia, or lymphangitis
carcinomatosis, may have extensive parenchymal lung disease on
chest x-ray without significant dyspnoea, especially early in the
course of the illness.
 Wheezing is an uncommon manifestation of ILD but has been
described in patients with chronic eosinophilic pneumonia,

20.  Clinically significant chest pain is uncommon in most ILDs.
 However, substernal discomfort is common in sarcoidosis.
 Sudden worsening of dyspnoea, especially if associated
acute chest pain, may indicate a spontaneous pneumothorax,
tuberous sclerosis, LAM, and neurofibromatosis.
 Frank haemoptysis and blood-streaked sputum are rarely
presenting manifestations of ILD but can be seen in the DAH
syndromes, LAM, tuberous sclerosis, and the granulomatous
vasculitides.
 Fatigue and weight loss are common in all ILDs.

22. PHYSICAL EXAMINATION
 The findings are usually not specific.
 Most commonly, physical examination reveals tachypnoea and bibasilar
end-inspiratory dry crackles, which are common in most forms of ILD
associated with inflammation but are less likely to be heard in the
granulomatous lung diseases.
 Crackles may be present in the absence of radiographic abnormalities
on the chest radiograph.
 Scattered late inspiratory high-pitched rhonchi—so-called inspiratory
squeaks—are heard in patients with bronchiolitis.
 The cardiac examination is usually normal except in the mid or late
stages of the disease, when findings of pulmonary hypertension and
cor-pulmonale may become evident.
 Cyanosis and clubbing of the digits occur in some patients with
advanced disease.

23. INVESTIGATIONS
 Antinuclear antibodies and anti-immunoglobulin antibodies
(rheumatoid factors) are identified in some patients, even in the
absence of a defined CTD.
 An increased lactate dehydrogenase (LDH) level is a nonspecific
finding common to ILDs.
 Elevation of the serum angiotensin-converting enzyme level is
common in sarcoidosis.
 Serum precipitins confirm exposure when hypersensitivity
pneumonitis is suspected, although they are not diagnostic of the
process.
 Antineutrophil cytoplasmic or anti–basement membrane
antibodies are useful if vasculitis is suspected.

24. INVESTIGATIONS electrocardiogram is usually normal unless pulmonary
hypertension is present; then it demonstrates right-axis
deviation, right ventricular hypertrophy, or right atrial
enlargement or hypertrophy.
 Echocardiography also reveals right ventricular dilatation,
hypertrophy, or both in the presence of pulmonary
hypertension.

25. CHEST X-RAY
 ILD may be first suspected based on an abnormal chest radiograph,
which most commonly reveals a bibasilar reticular pattern.
 A nodular or mixed pattern of alveolar filling and increased reticular
markings may also be present.
 A subgroup of ILDs—sarcoidosis, chronic hypersensitivity pneumonitis,
silicosis, berylliosis, RA (necrobiotic nodular form), ankylosing
spondylitis— exhibit nodular opacities with a predilection for the upper
lung zones.
 The chest x-ray correlates poorly with the clinical or histopathologic stage
of the disease.
 The radiographic finding of honeycombing correlates with pathologic
findings of small cystic spaces and progressive fibrosis; when present, it
portends a poor prognosis.
 In most cases, the chest radiograph is nonspecific and usually does not

26. COMPUTED TOMOGRAPHY
 HRCT is superior to the plain chest x-ray for early detection and
confirmation of suspected ILD.
 Coexisting disease (e.g., mediastinal adenopathy, carcinoma, or
emphysema) is often best recognized on HRCT scanning.
 In the appropriate clinical setting, HRCT may be sufficiently
characteristic to preclude the need for lung biopsy in patients with
IPF, sarcoidosis, hypersensitivity pneumonitis, asbestosis,
lymphangitic carcinoma, and PLCH.
 When a lung biopsy is required, HRCT scanning is useful for
determining the most appropriate area from which biopsy samples
should be taken.

27. PULMONARY FUNCTION TESTING
Spirometry and Lung Volumes
 Measurement of lung function is important in assessing the extent of pulmonary
involvement in patients with ILD.
 Most forms of ILD produce a restrictive defect with reduced total lung capacity (TLC),
functional residual capacity, and residual volume.
 Forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) are
reduced, but these changes are related to the decreased TLC.
 The FEV1/FVC ratio is usually normal or increased. Lung volumes decrease as lung
stiffness worsens with disease progression.
 A few disorders produce interstitial opacities on chest x-ray and obstructive airflow
limitation on lung function testing (uncommon in sarcoidosis and hypersensitivity
pneumonitis but common in tuberous sclerosis and LAM).

28. Arterial Blood Gas:
 The resting arterial blood gas may be normal or reveal
hypoxemia (secondary to a mismatching of ventilation to
perfusion) and respiratory alkalosis.
 A normal arterial O2 tension (or saturation by oximetry) at
rest does not rule out significant hypoxemia during exercise
or sleep.
 Carbon dioxide (CO2) retention is rare and is usually a
manifestation of end-stage disease.

29. CARDIOPULMONARY EXERCISE TESTING :
 useful to perform exercise testing with measurement of
arterial blood gases to detect abnormalities of gas
exchange.
 Arterial oxygen desaturation, a failure to decrease dead
space appropriately with exercise ratio, and an excessive
increase in respiratory rate with a lower than expected
recruitment of tidal volume provide useful information
about physiologic abnormalities and extent of disease.
 Serial assessment of resting and exercise gas exchange is
an excellent method for following disease activity and
responsiveness to treatment
 Increasingly, the 6-min walk test is used to obtain a global
evaluation of submaximal exercise capacity in patients with
ILD.
 The walk distance and level of oxygen desaturation tend
correlate with the patient’s baseline lung function and
mirror the patient’s clinical course.

30. FIBEROPTIC BRONCHOSCOPY AND BRONCHOALVEOLAR LAVAGE (BAL)

31. TISSUE AND CELLULAR EXAMINATION
 Lung biopsy is the most effective method for confirming the diagnosis and
assessing disease activity.
 The findings may identify a more treatable process than originally suspected,
particularly chronic hypersensitivity pneumonitis, COP, respiratory
bronchiolitis–associated ILD, or sarcoidosis. Biopsy should be obtained
before the initiation of treatment.
 Fiberoptic bronchoscopy with multiple transbronchial lung biopsies (4-8
samples) is often the initial procedure of choice, especially when sarcoidosis,
lymphangitic carcinomatosis, eosinophilic pneumonia, Goodpasture
syndrome, or infection is suspected.
 If a specific diagnosis is not made by transbronchial biopsy, surgical lung
biopsy by video-assisted thoracic surgery or open thoracotomy is indicated.
 Adequate-sized biopsies from multiple sites, usually from two lobes, should
be obtained.
 Relative contraindications to lung biopsy include serious cardiovascular
disease, honeycombing and other roentgenographic evidence of diffuse end-
stage disease, severe pulmonary dysfunction, and other major operative
risks, especially in the elderly.

32. MANAGEMENT OF ILD
 Although the course of ILD is variable, progression is common
and often insidious.
 Because therapy does not reverse fibrosis, the major goals of
treatment are
1) Permanent removal of the offending agent, when known
2) Early identification and aggressive suppression of the acute
and chronic inflammatory process, reducing further lung
damage.
3) Supplemental oxygen for Hypoxemia.
4) Treating underlying infections, cor-pulmonale.
5) Pulmonary rehabilitation to improve the quality of life in
patients

33.  Glucocorticoids: First line therapy for suppression of the
inflammation present in ILD, but the success rate is low.
 Glucocorticoid therapy is recommended for
 symptomatic ILD patients with eosinophilic pneumonias,
 COP, CTD, sarcoidosis,
 hypersensitivity pneumonitis, acute inorganic dust
exposures,
 acute radiation pneumonitis, DAH, and drug-induced ILD.
 In organic dust disease, glucocorticoids are recommended for
both the acute and chronic stages.

34. GLUCOCORTICOIDS
 Starting dose is prednisone, 0.5–1 mg/kg OD oral
 This dose is continued for 4–12 weeks, at which time
the patient is reevaluated.
 If the patient is stable or improved, the dose is tapered
to 0.25–0.5 mg/kg and is maintained at this level for
an additional 4–12 weeks, depending on the course.
 If the patient’s condition continues to decline on
glucocorticoids, a second agent (Cyclophosphamide,
azathioprine ) often is added and the prednisone dose is
lowered to or maintained at 0.25 mg/kg OD.

35. GLUCOCORTICOIDS
 Cyclophosphamide, azathioprine (1–2 mg/kg lean body weight
per day), and mycophenolate mofetil, with or without
glucocorticoids, have been tried with variable success in IPF,
vasculitis, progressive systemic sclerosis, and other ILDs.
 An objective response usually requires at least 8–12 weeks to
occur.
 In situations in which these drugs have failed or could not be
tolerated, other agents, including methotrexate and cyclosporine,
have been tried.
 Many cases of ILD are chronic and irreversible despite the therapy,
and lung transplantation may then be considered.

36. IDIOPATHIC PULMONARY FIBROSIS
 Also known as usual interstitial pneumonia(UIP)
 most common form of idiopathic interstitial pneumonia.
 IPF has a distinctly poor response to therapy and a bad prognosis.
 Type I pneumocytes are lost, and there is proliferation of alveolar
type II cells.
 Clinical Manifestations:
 Exertional dyspnoea, Non-productive cough, and
 inspiratory crackles with or without digital clubbing may be
present on physical examination.

38. IDIOPATHIC PULMONARY FIBROSIS
 HRCT lung scans typically show patchy, predominantly basilar, subpleural
reticular opacities, often associated with traction bronchiectasis and
honeycombing.
 A definite UIP pattern on HRCT is highly accurate for the presence of a UIP
pattern on surgical lung biopsy.
 Atypical findings that should suggest an alternative diagnosis include
extensive ground-glass abnormality, nodular opacities, upper or midzone
predominance, and prominent hilar or mediastinal lymphadenopathy.
 Pulmonary function tests often reveal a restrictive pattern, a reduced DlCO,
and arterial hypoxemia that is exaggerated or elicited by exercise.

40. Management of IPF:
 Untreated patients with IPF show continued progression of their disease and have a
high mortality rate.
 There is no effective therapy for IPF.
 Thalidomide appears to improve cough in patients with IPF.
 Chronic microaspiration secondary to gastroesophageal reflux may play a role in the
pathogenesis and natural history of IPF.
 Gastroesophageal reflux (GER) therapy may be of benefit in IPF.
 In patients with IPF, treatment with the three-drug regimen of prednisone,
azathioprine, and N-acetylcysteine (NAC) or warfarin (in IPF patients who lacked
other indications for anticoagulation) has been shown to increase the risks of
hospitalization and death.
 Patients with IPF and coexisting emphysema (combined pulmonary fibrosis and
emphysema [CPFE]) are more likely to require long-term oxygen therapy and
develop pulmonary hypertension and may have a more dismal outcome than those
without emphysema.
 Patients should be referred early for lung transplant because of the unpredictability
of disease progression

41. Disease Age
M:F
C/F Imaging Prognosis REMARKS
Nonspecific
interstitial
pneumonitis
(NSIP)
40-50 May be
indistinguishabl
e from UIP
Bilateral,
subpleural
ground glass
opacities asso
with lower lobe
volume loss
Prognosis
good but
depends on
the extent
of fibrosis
at
diagnosis
greater
than 10
years.
But
Surgical
Biopsy is
needed to
confirm.
Cryptogenic
organizing
pneumonitis
(bronchioliti
s obliterans
organizing
pneumonia
[BOOP])
50–60 Abrupt onset,
frequently
weeks to a few
months
following a flu-
like illness.
constitutional
symptoms are
common
areas of air-
space
consolidation,
ground-glass
opacities, small
nodular
opacities, and
bronchial wall
thickening and
dilation.
Good Rule out
infection
and treat
with
steroids

42. Disease Age
M:F
C/F Imaging Prognosis REMARKS
Respiratory
bronchiolitis-
associated
interstitial
lung disease
younger Heavy
smokers
with
similar
complains
Like UIP.
Bronchial wall
thickening,
centrilobular
nodules, ground
glass opacity
with
Airtrapping
Emphysematous
change.
survival
greater
than 10 y
Spontaneo
us
remission
20%.
ILD with
Obstructiv
pattern
Acute
interstitial
pneumonitis
Hamman-Rich
syndrome.
young Apparently
normal
indistinguis
hable from
that of
idiopathic
ARDS
ARDS
Diffuse b/l
airspace
consolidation
with patchy
symmetric areas
of ground-glass
attenuation
POOR Most
severe form
of ILD
Pneumonia

43. NONSPECIFIC INTERSTITIAL PNEUMONITIS
(NSIP)

44. CRYPTOGENIC ORGANIZING PNEUMONITIS
(BRONCHIOLITIS OBLITERANS ORGANIZING
PNEUMONIA [BOOP])

45. Smoking related ILD
Respiratory bronchiolitis- associated
interstitial lung disease

46. ACUTE INTERSTITIAL PNEUMONITIS

47. OCCUPATIONAL & RECREATIONAL
EXPOSURE RELATED ILD
Exposure Associated Lung Disease
Bird breeders and fanciers Hypersensitivity pneumonitis
Automotive mechanics, Electricians
Pipefitters
Shipyard workers
Asbestosis
Electronic and computer industry
workers
Berylliosis
Farmers Farmer’s lung (hypersensitivity
pneumonitis)
Hot tub, sauna, humidifiers Hypersensitivity pneumonitis
Metal workers (tool and die) Metal-induced pneumoconioses
Miners, Sandblasters, Ceramic
workers
Silicosis
Miners (specifically coal) Coal workers’ pneumoconiosis

48. Coal miners
pneumoconioisis
Rounded opacities between 1 and 5 mm
(upper and middle zones)
small irregular and linear opacities
Progressive massive fibrosis
almost always starts in an upper zone
Calcification is not a feature
Cavitation of PMF can occur
Caplan's syndrome is the name given to the combination
of rheumatoid disease and several round nodules (usually
1 to 5 cm in diameter) in the lungs of a coal miner.

49. SILICOSIS
Clues to diagnosis
Micronodular pattern
Simple silicosis :
Upper lobes
Small multiple nodules
Egg shell calcification
Complicated :
>1 cm nodules
Acute silicosis :
small nodular pattern with ground glass
appearance ( crazy paving )
PMF : nodules coalesce to large masses
BAL : dust particles on polarised light

50. Clues to diagnosis
X Ray:
reticular interstitial pattern
pleural plaques ( lower lung field , cardiac
border and diaphragm )
Irrregular linear opacities first noted in
lower lung fields.
HRCT :
Distinct subpleural curvilinear opacities 5-
10 mm length parallel to pleural surface
BAL:
Asbestos bodies
ASBESTOSIS

51. HYPERSENSITIVITY PNEUMONITIS
 Hypersensitivity pneumonitis (HP), or extrinsic allergic
alveolitis, is a spectrum of interstitial, alveolar, and
bronchiolar lung diseases resulting from immunologically
induced inflammation in response to inhalation of a wide
variety of different materials that are usually organic or low-
molecular weight chemical antigens (or haptens) that may
lead to irreversible lung damage.
 Despite the terms hypersensitivity and allergic, HP is not an
atopic disease and is not associated with increased IgE or
eosinophils.

52. HYPERSENSITIVITY PNEUMONITIS
 Hypersensitivity pneumonitis (HP) has Acute, subacute & chronic
manifestations.
 Acute manifestations include:
 transient fever, hypoxemia, myalgias, arthralgias, dyspnoea, and
cough that occur 2 to 9 h after exposure and resolve in 12 to 72 h
without specific treatment (sometimes longer after a particularly
intense exposure).
 Patients exhibit tachypnea, bibasilar rales, and occasionally cyanosis.
 There is usually peripheral blood leukocytosis with neutrophilia and
lymphopenia (without eosinophilia), and bronchoalveolar lavage
(BAL) neutrophilia.
 Subacute or intermittent disease may result from repeated exposures,
and manifest as
 productive cough, dyspnea, fatigue, and weight loss.
 There may be BAL lymphocytosis, frequently (although not always)
with a predominance of CD8+ T lymphocytes.

53. HYPERSENSITIVITY PNEUMONITIS Chronic HP is clinically more insidious, and patients may lack a
history of acute episodes.
 present with a gradual onset of cough, dyspnea, fatigue, and
weight loss.
 Symptoms are usually present for months to years.
 There is typically no fever, but tachypnea and bibasilar dry
rales are usually present.
 This form of the disease may be difficult to distinguish from
idiopathic pulmonary fibrosis.
 symptoms and signs of cor-pulmonale are not uncommon at
presentation.

54. bilateral lower lobe 2- to 3-mm
nodules
diffuse nodular radiodensities in the lower
lobes, with areas of ground- glass densities
posteriorly.

55. INTERSTITIAL LUNG DISEASE IN CTD
 Suspect a CTD if patient has :
 Musculosketetal pain
 Weakness
 Fatigue
 Joint pains and swelling
 Photosensitivity
 Raynauds phenomenon
 Pleuritis
 Dry eyes or mouth

56. Progressive Systemic Sclerosis (PSS)
• Clinical evidence of ILD is present in about one-half of patients with
progressive systemic sclerosis (PSS), and pathologic evidence is
present in three-quarters.
• Pulmonary function tests show a restrictive pattern and impaired
diffusing capacity, often before any clinical or radiographic evidence
of lung disease appears.
• Pulmonary vascular disease alone or in association with pulmonary
fibrosis, pleuritis, or recurrent aspiration pneumonitis is strikingly
resistant to current modes of therapy.

57. Rheumatoid Arthritis
• ILD associated with RA is more common in men.
• Pulmonary manifestations of RA include
• pleurisy with or without effusion,
• ILD in up to 20% of cases,
• necrobiotic nodules (nonpneumoconiotic
intrapulmonary rheumatoid nodules) with or
without cavities,
• Caplan’s syndrome (rheumatoid
pneumoconiosis),
• pulmonary hypertension secondary to
rheumatoid pulmonary vasculitis,
• BOOP, and
• upper airway obstruction caused by
cricoarytenoid arthritis.

58. Systemic Lupus Erythematosus
• Lung disease is a common complication in SLE.
• Pulmonary manifestations”
• Pleuritis with or without effusion is the most common.
• atelectasis,
• diaphragmatic dysfunction with loss of lung volumes,
• pulmonary vascular disease,
• pulmonary hemorrhage,
• uremic pulmonary edema,
• infectious pneumonia,and
• BOOP.
• Acute lupus pneumonitis characterized by pulmonary capillaritis leading to
alveolar hemorrhage is uncommon.
• Chronic,progressive ILD is uncommon.It is important to exclude pulmonary
infection.
• Although pleuropulmonary involvement may not be evident clinically,
pulmonary function testing reveals abnormalities in many patients with SLE.

59. Polymyositis and Dermatomyositis
• ILD occurs in ∼10% of patients with polymyositis and
dermatomyositis (PM/DM).
• Diffuse reticular or nodular opacities with or without an alveolar
component occur radiographically, with a predilection for the
lung bases.
• ILD occurs more commonly in the subgroup of patients with an
anti–Jo-1 antibody that is directed to histidyl tRNA synthetase.
• Weakness of respiratory muscles contributing to aspiration
pneumonia may be present.
• A rapidly progressive illness characterized by diffuse alveolar
damage may cause respiratory failure.

60. HRCT in RA
bibasilar peripheral reticular pattern,
intralobular interstitial thickening
distortion of the lung parenchyma
Bilateral is present, predominantly on the
left side
bibasilar peripheral reticular pattern,
pleural effusion
thickening of the interlobular septa,

61. DRUG REACTIONS CAUSING ILD
 Alveolar Haemorrhage:
 Amiodarone, Amphotericin B, Clopidogrel, Cocaine,
Cyclophosphamide, Haloperidol, Heparin, Hydralazine, Mitomycin,
Nitrofurantoin, Penicillamine, Statins, Streptokinase, Sulfonamides
 BOOP (bronchiolitis obliterans organizing pneumonia )
 Carbamazepine, Cephalexin, Chloroquine, Cocaine,
Cyclophosphamide, interferon-a Mecamylamine Mesalamine
Methotrexate,Nitrofurantoin, Phenytoin, Statins, Sulfasalazine
 Constrictive bronchiolitis
 Busulfan, penicillamine

62. EOSINOPHILIC PNEUMONIAS
 Classified as:
1) simple eosinophilic pneumonia (Loeffler syndrome),
2) acute eosinophilic pneumonia (AEP)-a process that
clinically resembles ARDS,
3) chronic eosinophilic pneumonia (CEP) that has a
longer time course and does not result in
respiratory failure.

65. AEP CEP

66. RADIATION PNEUMONITIS
 evident 6 weeks to 6 months following radiotherapy
 radiographs show alveolar opacities that generally conform to the
treatment portals.
 In most cases, the pneumonitis is asymptomatic
 If symptomatic, characterized by the abrupt onset of fever, cough,
and dyspnea.
 Managed with supportive care in conjunction with
Glucocorticoids.

68. Vasculitic
Disorders
Lung
Involvement
ANCA Interstial Pattern
seen
Wegener
granulomatosis
Common c-ANCA >> p-
ANCA
80–90%
Diffuse Alveolar
Hemorrage with
nodules
,cavitation
Microscopic
polyangiitis
Common Common p-
ANCA > c-ANCA
80%
DAH
Churg-Strauss
syndrome
Common p-ANCA > c-
ANCA
30–50%
DAH with
transient infiltates
Goodpasture
syndrome
Common p-ANCA
10%
DAH
Takayasu arteritis Common Negative DAH
ILD WITH A GRANULOMATOUS OR VASCULAR STRUCTURES

69. X ray : consolidation, typically resolving within a matter of days, multiple
abcesses
HRCT : ground-glass partial alveolar filling.
Hb : anaemia ( iron defeciency )
BAL :- frank blood-staining in sequential lavage (acute presentation) and
numerous macrophages containing iron, identified by Perl's stain
Dlco :- may be increased in acute conditions but is chronically low
ILD in VASCULITIC
DISORDERS
Suspect if
Mononeuritis mutiplex
Renal involvement
Skin lesions
haemoptysis

70. SARCOIDOSIS
 Probably one-third of sarcoid patients who come to medical
attention are asymptomatic, and the disease is picked up as an
incidental finding on chest imaging.
 Another one third have fever, malaise, and weight loss, and an
equal proportion have shortness of breath (SOB), cough, and
sometimes chest pain.
 Pulmonary function varies by radiologic stage.
 Low-stage disease patients may have normal pulmonary
function, but airflow obstruction (because sarcoid granulomas
can narrow the large and small airways and restriction are also
seen.
 High-stage (i.e., diffuse fibrotic) disease shows a restrictive
pattern with decreased diffusing capacity; pulmonary
hypertension may also be present.

71. • Stage 0: No demonstrable radiographic
abnormality
•
Stage 1: Hilar and mediastinal lymph
node enlargement
• without radiographic parenchymal
abnormality
• Stage 2: Hilar and mediastinal. lymph
node enlargement plus parenchymal
abnormality
• Stage 3: Parenchymal abnormality
alone
• Stage 4: Advanced fibrosis.

73. SARCOIDOSIS CTD….
BAL :- lymphocytosis
CD4 : CD8 > 3.5 is most specific
PFT :- Restrictive pattern
But Obstructive component present in many
Biopsy :- non caseating granulomas
lymphocytosis
Sr. ACE levels:-
Hyper calciuria or Hypercalcemia

74. LYMPHOCYTIC INFILTRATIVE DISORDERS
 This group of disorders features lymphocyte and plasma cell
infiltration of the lung parenchyma.
 Are benign or can behave as low-grade lymphomas.
 characterized by diffuse lymphadenopathy, fever, hepato-
splenomegaly, and hemolytic anemia, with ILD in some cases.
 Lymphocytic Interstitial Pneumonitis
 Lymphomatoid Granulomatosis
 histologic findings : angiocentric malignant (T cell) lymphoma
characterized by a poly- morphic lymphoid infiltrate, an angiitis,
and granulomatosis.

76. PULMONARY ALVEOLAR PROTEINOSIS
 The clinical features of (PAP) are nonspecific
 cough, shortness of breath (SOB), malaise, and
sometimes chest pain or weight loss, usually
developing in an indolent fashion.
 Chest examination is frequently unremarkable,
although crackles, clubbing, and cyanosis are
reported.

77. PULMONARY ALVEOLAR PROTEINOSIS
diffuse reticulo-alveolar infiltrates
BAT WING distribution
BAL:- milky effulent foamy
macrophages with lipoproteinous
intraalveolar material
thickened interlobular septa
“crazy paving” ground glass
fashion, sharply demarked from
normal lung creating a
“geographic” pattern.

78. PROGNOSIS
 Some forms of interstitial lung disease resolve
completely, while others lead to long-term and
irreversible scarring and lung damage with
accompanying respiratory failure .
 Pulmonary hypertension can develop in cases of long-
standing interstitial lung disease and can lead to cor
pulmonale
 The prognosis is dependent upon the type and severity
of interstitial lung disease as well as the underlying
health status of the patient.

79. PREVENTION
 Avoid or limit exposure to toxins or treatments that can lead to ILD
 Proper diet and exercise reduces chance of developing ILD.
 Quitting smoking and avoiding exposure to substances known to
cause ILD can prevent the disorder from developing or worsening.
 People who are employed in jobs where they may be heavily
exposed to known causes of lung disease in the workplace
typically should undergo routine screening for lung disease.

80. THANK YOU
References:
 Harrison’s principles of Internal Medicine 19th Ed.
 Murray and Nadel’s Textbook of Respiratory Medicine 6th Ed
 Fishman’s Pulmonary Diseases and Disorders 4th Ed
 Atlas of Interstitial Lung Disease Pathology 2014 – Churg &
Muller