Interstitial Lung Diseases A group of disorders affecting primarily the Interstitium but also affects the parenchyma (Alveoli and respiratory bronchioles) and the vascular bed . The ultimate result of these disorders is reduction of pulmonary volumes and capacities

. . . . . . . . . . . ALVEOLUS . . . . . . CAPILLARY . . . . INTERSTITIUM

Common clinical features Symptoms 1-Chronic dry cough 2-Exertional dyspnea Signs 1-Clubbing 2-Basal inspiratory crepitations Laboratory 1-High ESR 2-Pulmonary infeltrate and reduced lung size 3-Restrictive pattern of pulmonary function tests

Pulmonary Function Tests Spirometry 1-Decreased FEV1,FEV (Normal FEV1/FVC) 2-Decreased TLC 3-Mildly Decreased PEF 4-Markedly Decreased DLCO Blood gasses 1-Hypoxia 2-Hypocapnea (Type 1 respiratory failure)

Rare features of ILD 1-Excessive sputum and hemoptysis 2-Pleurisy 3-Wheezing 4-Chest pain

Interstitial Lung Disease Blood tests Interstitial Lung Disease Occupational Treatment related Connective tissue disease Idiopathic Immunological Asbestosis Silicosis Coal Workers pneumoconiosis Radiation Methotrexate Nitrofurantoin Amiodarone Chemotherapy Rh. Arthritis SLE Polymyositis Schleroderma Sjogren’s Sarcoidosis Hypersensitivity pneumonitis CFA/IPF UIP/NSIP DIP LIP RB-ILD BOOP

PULMONARY FIBROSIS Localized unilateral fibrosis may result from a destructive pneumonia, trauma, or tuberculosis Localized bilateral fibrosis may occur in bronchiectasis, tuberculosis, histoplasmosis and other chronic infections Generalized fibrosis: In end-stage of a range of parenchymal lung disorders where the diffuse inflammatory process ends with diffuse fibrosis .

Idiopathic Pulmonary Fibrosis (Cryptogenic Fibrosing Alveolitis) The most common of the interstitial lung diseases 5-10 per 100 000 people Men : women (2:1) Most commonly seen in those over 65 years of age. Alveolitis Alveolar destruction Fibrosis Function impairment

The course of the disease Usually is a progressive disease to end stage lung damage and respiratory failure over years May have a rapid course (Months) May be a mild disease discovered accidentally

Clinical Presentation Exertional dyspnea Which increases in severity over months or years Cough, Dry Arthralgia even in absence of connective disease. Clubbing of the fingers Late inspiratory fine crackles at the lung bases.

Diagnosis Chest X-ray Lower zone shadowing Decreased lung size Pulmonary function tests show a restrictive defect, often with a great reduction in transfer factor. ESR is usually moderately raised. Positive autoantibodies and there is an association with other autoimmune diseases. Lung biopsy may be necessary for diagnosis and shows characteristic changes

Pulmonary function tests

Treatment Systemic corticosteroids Immunosuppression with cyclophosphamide and azathioprine may be added. The response to treatment is better if inflammation is more marked than fibrosis in the lung histology.

Prognosis The long-term outlook is poor with a mean survival of 5 years. The causes of death are supervening infection, cor pulmonale or respiratory failure and bronchial carcinoma. Younger and otherwise fit patients with severe disease should be considered for heart-lung transplantation.

Extrinsic Allergic Alveolitis (Hypersensitivity Pneumonitis) A result of a hypersensitivity reaction in the lungs, provoked by a wide range of organic dusts. Repeated exposure of a susceptible individual to the offending antigen leads to the production of circulating precipitating antibodies and immune complexes and ultimately to macrophage activation and epithelioid cell granuloma formation. Farmer’s lung is the most common cause, accounting for 50% of cases of extrinsic allergic alveolitis. Bird fanciers lung occur in 5% of bird owners and 20% of pigeon keepers.

Symptoms Symptoms may develop within 6 hours of heavy exposure to the antigen or may appear insidiously over years. The most common presentation is with breathlessness, dry cough and influenza-like symptoms (malaise, fever and muscle pains).

Investigations Chest X-ray Acute phase :a fine nodular shadowing Repeated exposure :fibrotic changes more marked in the upper azones, as with sarcoidosis, than in the lower zones, as with cryptogenic fibrosing alveolitis. Lung function shows restrictive pattern (reduced TLC and FVC), Plus decreased DLCO

Treatment The provoking factor must be identified and removed Systemic corticosteroids may be required and may accelerate recovery.

Sarcoidosis A rare multisystem granulamatous disorder of young patients. The Lungs and its Lymph Nodes are the mostly affected But it can involve the skin, eyes, peripheral lymph nodes, gut, liver, bone and CNS. The pathological process is a granulomatous reaction.

There is a slightly increased incidence within families and in women. In the USA it is much more common in black patients.

clinical presentation The most common clinical presentation of sarcoidosis is respiratory. Nonspecific features such as tiredness, weight loss or recurrent fever. The characteristic lesions are - Bilateral hilar lymphadenopathy , asymptomatic, subside without treatment in about 80-90% of patients - Pulmonary infiltration and bilateral hilar lymphadenopathy which may cause symptoms such as dyspnoea, cough and fever, but subsides in 40% of patients - Pulmonary fibrosis with diffuse infiltration, ultimately leading to a restrictive defect on respiratory function testing. Evidence of the disease should be sought in the skin, eye and peripheral lymph nodes.

Diagnosis Biopsy of lymph nodes, skin or lung. Lung function tests often show a restrictive defect Mantoux test is often negative.

Treatment Treatment of sarcoidosis depends on the extent of the disease and the tissues involved. Parenchymal lung disease, acute eye involvement and CNS or heart signs require a prolonged course of steroids. Minor skin or lymph node involvement can be watched over a period of months for spontaneous resolution.

Clubbing

Sarcoid skin lesion

Lupus pernio

Lupus pernio

Pulmonary infeltrate

Hilar adenopathy

Pulmonary Infiltration with Eosinophilia The association of blood eosinophilia and pulmonary shadowing may occur in a number of situations Simple pulmonary eosinophilia Short-lived and usually self-limiting illness with cough and a slight fever are associated with transient pneumonic shadowing and blood eosinophilia. Commonly due to worm infestation or drug therapy Allergic BronchoPulmonary Aspergillosis (ABPA) Presents as asthma with poor control and fleeting pulmonary infeltrate with marked blood and sputum eosinophilia Tropical pulmonary eosinophilia, Wuchereria bancrofti infection

IATROGENIC LUNG DISEASE Radiotherapy, usually given for diseases such as cancer of the breast, bronchus, thymus or lymph nodes. The lung damage depends on Total radiation dose Duration of time over which the dose is given The number of treatments. The concomitant use of pulmonary toxic chemotherapeutic drugs

Acute Radiation Pneumonitis Occurs a few days to some weeks after exposure and presents with a cough, fever and progessive dyspnoea. Corticosteroids may ameliorate these acute symptoms. Chronic Radiation Pneumonitis Fibrosis may develop over many months and there is evidence of a progressive restrictive defect in the pulmonary function tests with a decrease in transfer of carbon monoxide.

Examples of drug induced lung damage A large number of drugs, alone or in combination, may produce a range of respiratory problems that include Asthma (e.g. b-blockers) Infiltration or fibrosis (e.g. bleomycin, methotrexate) Eosinophilia (e.g. nitrofurantoin) Systemic lupus erythematosus-like syndromes (e.g. hydrallazine) Respiratory depression (e.g. opiates, barbiturates) ARDS- opiates , thiazides Opportunistic infection (e.g. high dose steroids, immunosuppressives).

OCCUPATIONAL LUNG DISEASE Lung diseases associated with industrial exposure are a common problem. They can be avoided if appropriate occupational regulations are enforced, especially efficient ventilation and individual protection by ventilators or masks..

VASCULITIS Wegener's granulomatosis Classic Wegener’s granulomatosis consists of the clinical triad of 1-upper respiratory tract granulomas 2-fleeting lung shadows with cavitation 3-necrotizing glomerulonephritis Allergic granulomatosis (Churg-Strauss syndrome) Asthma that is difficult to control high blood eosinophilia lungs, nervous system, skin and heart are often involved renal involvement is minimal

Pulmonary involvement in connective tissue diseases Rheumatoid arthritis Fibrosing alveolitis obliterative bronchiolitis and bronchiectasis multiple or single pulmonary nodules, which may cavitate, and pleural effusions Exhudative pleural effusion Systemic lupus erythematosus Pleurisy and pleural effusion lung atelectasis in Systemic sclerosis. pulmonary hypertension and basal fibrosis

This patient is not responding to treatment of acute severe asthma, WHY?

The name