1. Interstitial Lung Disease (ILD) Mike McFarlane (CT1) 12/5/12 SLIME

2. What we’ll cover Definition Different types of ILD Pathophysiology Presentation Investigations Management Prognosis Clinical Scenario Summary

3. What we won’t... Other causes of restrictive lung defects – Thoracic cage defects Anything fun!!

4. Definition Interstitial lung disease is a diverse group of conditions affecting the pulmonary interstitium and/or the alveolar lumen Not airways! The gas exchange parts and support tissue

5. Different types of ILD Idiopathic Pulmonary Fibrosis AKA: Cryptogenic fibrosing alveolitis, Usual interstitial pneumonitis Extrinsic Allergic Alveolitis AKA: Hypersensitivity pneumonitis Other Industrial lung diseases Sarcoidosis

6. Pathophysiology Cycles of inflammation, scarring and fibrosis leads to irreversible damage to interstitial tissue IPF: ?autoimmune EAA: – Farmer’s Lung: Micropolyspora faeni/ Aspergillus Fumigatus – Bird Fancier’s Lung: Avian serum proteins – Malt worker’s Lung: Aspergillus clavatus – Inhalation (humidifier) fever: Thermophillic actinomycetes Other “dust” diseases: (CABS) – Coal Workers Pneumoconiosis: Coal Dust Caplan’s Syndrome: CWP + Rheumatoid arthritis – Asbestosis: Asbestos – Beryllosis: Beryllium – Silicosis: Silicon Sarcoidosis: Multisystem autoimmune non-caseating granulomatous disorder

7. Presentation Symptoms – SOB on exertion – Lethargy – Dry cough – EAA – variability with work; IPF – progressive worsening – Sarcoid extrapulmonary features: – Anterior uveitis, conjunctivitis, arthralgia, erythema nodosum – SMOKING, OCCUPATION, PETS Signs – Tachypnoeic – Clubbing – IPF, EAA – Cyanosis – Fine end-inspiratory creps IPF – more at bases EAA – more at apices

8. Investigations Bedside – PEF, including work and home measurements – Sats, RR Blood tests – FBC, U&Es, LFTs, CRP, ESR – ABG - hypoxia – ANA and RF can be + in IPF – Calcium can be high in Sarcoidosis (serum ACE can be high but not always!) Imaging – CXR – fine reticulonodular shadowing – CT Ground glass appearance Honey combing

9. Investigations (2) Special tests – Spirometry Restrictive defect i.e. Lung volume reduced. FVC reduced, FEV1 reduced in proportion (or slightly less). Therefore FEV1:FVC is normal or high!! TLCO (transfer factor) reduced – due to fibrosis of alveolar walls. Means a thicker barrier to gas exchange and less effective transfer – N.B. Bronchoscopy, BAL, Biopsy

10. Reticulonodular shadowing

11. Honey combing and Ground Glass

12. Management Conservative – Smoking cessation – Change working conditions – Change work Medical – Depends on cause!! – IPF – very little besides oxygen! Steroids of little help – EAA – Steroids for acute episodes – Sarcoidosis – Only treat if extrapulmonary manifestations! Steroids Surgical – Lung transplant

13. Prognosis IPF – poor EAA – depends on extent of disease and ability to avoid the cause Industrial lung disease - variable Sarcoidosis - variable

14. Clinical scenario A 64 year old gentleman presents to his GP with increasing SOB over the last 6 months. His exercise tolerance has reduced to the point where walking to the corner shop makes him out of breath. He also complains of a dry cough. He has a past medical history of high blood pressure which is managed with Ramipril. He has never smoked and works as an office manager He has no pets On examination he is slightly short of breath with O2 sats 93% on air and he has clubbing. Auscultation reveals bilateral basal fine end inspiratory crepitations and no wheeze.

15. Clinical scenario Cont What are your main differentials for this gentleman? How would you investigate this gentleman? What is your management plan? Will anything help?

16. Summary ILD is more complicated than it needs to be Cardinal features are: – Fine end inspiratory creps – due to fibrosis – The cause of the fibrosis will usually be hinted at in occupation or hobbies! – If no cause obvious its probably IPF Restrictive spirometry with reduced gas transfer Treatment depends on cause – usual steroids

17. QUESTIONS ?