Interstitial Lung Disease
Presentation
Sir, this patient has interstitial lung disease affecting both lower lobes (upper lobes) as
evidenced by fine velcro-like late inspiratory crepitations heard best
posteriorly(anteriorly) in the lower one third bilaterally. This is associated with
clubbing(50%) and a non-productive cough.
Chest excursion was reduced bilaterally with a normal percussion note and vocal
resonance. Trachea is central and apex beat is not displaced.
There are no signs of pulmonary hypertension or cor pulmonale. There are also no
features of polycythemia.
Patient respiratory rate is 14 breaths per minute and there are no signs of respiratory
distress. There are also no signs of respiratory failure. There is also no nicotine
staining of the fingers and I note that the patient is cachexic looking with wasting of
the temporalis muscles.
In terms of aetiology, there is no symmetrical deforming polyarthropathy of the hands
to suggest RA, or cutaneous signs to suggest presence of SLE, dermatomyositis or
scleroderma as these conditions may be complicated by pulmonary fibrosis.
With regards to treatment, patient is not Cushingoid and does not have papery thin
skin or steroid purpura to suggest chronic steroid usage. On inspection there are no
surgical scars to suggest open lung biopsy.
I would like to complete the examination by asking for a detailed drug history as well
as an occupational history.
In summary, this patient has got pulmonary fibrosis affecting bilateral lower lobes.
There are no complications of pulmonary hypertension, cor pulmonale and
polycythemia. He is clinically not in respiratory failure and has no features of chronic
steroid usage. The differential diagnoses include collagen vascular disease, drugs,
occupational causes and idiopathic pulmonary fibrosis.
Questions
What are the differential diagnoses for clubbing and crepitations?
 Pulmonary fibrosis
 Bronchiectasis
 Lung abscess
 Mitotic lung conditions
What are the characteristic auscultatory findings?
 Late, fine inspiratory crepitations
 Velcro-like
 Disappears or quietens with the patient leaning forwards
What are the causes of fibrosis?
 Upper Lobes
 S – Silicosis, sarcoidosis
 C- coal worker pnemoconiosis
 H- histiocytosis
 A- Ankylosing spondylitis, ABPA
 R – radiation
 T – TB
 Lower lobes
 R- RA
 A-Asbestosis
 S- Scleroderma
 I – Idiopathic pulmonary fibrosis
 O- others ie drugs
 Cytotoxics – MTX, Aza, bleomycin, bulsulphan, cyclo, chlorambucil
 CNS - Amitryptyline, phenytoin and carbamazepine
 CVS - Amiodarone, hydralazine, procainamide
 Antibiotics - Nitrofurantoin, isoniazid
 Antirheumatics – Gold, sulphasalazine
 Both
 N – Neurofibromatosis, Tuberous sclerosis
 E – Extrinsic allergic alveolitis (acute symptoms within 6 hrs of inhaled
allergens eg farmer’s lungs)
 P – pulmonary haemorrhage syndromes
 A – alveolar proteinosis
 Primary
 Secondary – Inhaled organic dusts(Silica, Al), chronic infection,
malignancy
 Lymphangiomyomatosis
How would you classify interstitial lung disease? (ATS/ERS 2001)
 Diffuse parenchymal lung disease(DPLD) of known cause
 Collagen Vascular disease
 RA, SLE, Dermatomyositis, Systemic sclerosis
 Occupational/Environmental
 Asbestosis, silicosis, extrinsic allergic alveolitis
 Drug related
 Cytotoxic, CNS, CVS, Antibiotics and antirheumatic
 Idiopathic
 IPF
 Other idiopathic interstitial pneumonias
 DIP
 AIP
 LIP
 NSIP
 Cryptogenic organising pneumonia
 Respiratory bronchiolitis
 Granulomatous
 Sarcoidosis
 Others - LAMs, histiocytosis
How would you diagnose idiopathic pulmonary fibrosis?
 Clinical-radiological-pathological diagnosis
 Clinical
o Exclusion of other causes of ILD
o >50 yrs, insidious onset of dyspnea, > 3months, non-productive cough
o Typical physical findings
 Radiological (see below)
 Pathological (see below)
How would you investigate?
The diagnostic Ix of choice is a HRCT of the thorax but simple IX such as CXR and
LFT are useful:
 CXR
 Diagnostic
 bilateral basal reticulonodular shadows, peripheries, which advances
upwards
 honeycombing in advanced cases (gps of closely set ring shadows)
 loss of lung volume
 Extent and distribution
 Complications
 Lung function
 Restrictive pattern (reduced TLC or VC with increased FEV1/FVC ratio)
 Severity of restriction based on TLC
 Reduced transfer factor (impaired gas exchange)
 HRCT scan
 Dx – patchy reticular abnormalities, focal ground glass, architectural
distortion, volume loss, subpleural cyst, honeycombing (no consolidation or
nodules)
 Extent and severity – basal, peripheral, subpleural
 Complications
 NB: Similar to that of collagen vascular disease and asbestosis
 Others
 Bronchoscopy – lavage
 Predominantly lymphocyte responds to steroids and better Px= not UIP
 Predominantly neutrophils and eosinophils means poor Px= UIP (if >20%
of eosinophils to consider eosinophilic lung disease)
 Lung biopsy
 IPF – Usual interstitial pneumonia
 Bloods
 ABGs
 To rule out causes
How would you manage?
 Education and counselling
 Stop smoking
 Regular follow up and vaccinations
 Treat underlying cause
 Pharmacological
 Trial of steroids


 If responding continue steroids
 If not responding, cyclophosphamide or azathioprine
 Antifibrotic agents
 Eg penicillamine which has not been proven to be useful
Surgical
 Lung transplant (single lung transplantation)
Manage complications
 Cor pulmonale - diuresis for heart failure
 Polycythemia - venesection if Hct >55%
 Respiratory failure – Oxygen therapy
 Monitor for lung cancer
What are the good prognosticating factors?
 Young age
 Female
 Short duration
 Ground glass appearance on the CXR
 Minimal fibrosis on lung biopsy
What is the clinical course of patients with IPF?
 Gradual onset
 Progressive
 Median survival from time of dx about 3 years
What are the causes of death?
 Cor pulmonale
 Respiratory failure
 Pneumonia
 Lung carcinoma
What is Hamman-Rich syndrome?
 Rapidly progressive and fatal variant of interstitial lung disease