What are Lung Diseases?Lung diseases are diseases that affect the lungs or cause the lungs to not able to function properly.Lung diseases are of a few types:1. Airway diseasesAsthma and Bronchitis:These diseases involve the tubes or airways that carry oxygen in and out of the lungs.Airway diseases usually cause a narrowing of the airways such as in asthma and bronchitis.2. Lung tissue diseases:These diseases damage the structure of the lung tissue such as.a. Pulmonary fibrosisb. Chronic obstructive lung disease,c. Primary and secondary lung cancerd. PneumoniaScarring or inflammation of the lung tissue makes the lungs unable to function properly.The damaged lung disease makes it difficult to breathe in oxygen and release carbon dioxideThese diseases are usually more severe and dangerous because of damage to the lungs.These lung diseases are the third commonest cause of death after cancer and heart disease.3. Lung circulation diseases:These diseases affect the blood flow in the blood vessels in the lungs and are caused by clotting, scarring, or inflammation of the blood vessels.As a result the lungs are unable to take up oxygen and to release carbon dioxide.These lung diseases can also affect heart function.a. Pulmonary embolismPulmonary embolism is a blood clot which forms in a vein, breaks free, travels through the heart and lodges in the lungs.Large pulmonary emboli are fatal, causing sudden deathb. Pulmonary edemaPulmonary edema is the leakage of fluid from capillaries of the lung into the alveoli or air sacs.This condition is usually due to congestive heart failure.c. Pulmonary hemorrhagePulmonary hemorrhage, inflammation and damage to capillaries in the lung can result in blood leaking into the alveoli.This may cause blood to be coughed up.4. Pleural Cavity diseasesa. Pneumothorax:These diseases are caused by a hole in the pleura (lining covering the lung) resulting in air escaping from the lungs into the pleural cavity.The lung can collapse as a result of the escape of air from the lung into the pleural cavity.This is called a pneumothorax and can present an emergency because the air in the pleural cavity can compress the heart and the air tubes of the lungs.b. Pleural Effusion:A pleural condition is the collection of the fluid in the pleural cavity called a pleural effusion.The collection of fluid may be due to infection or inflammation of the pleural lining such as tuberculosis and cancer.Fluid may also collects in the pleural cavity as a result of congestive heart failure.c. Pleural Mesothelioma (a cancer of the pleural lining) is usually caused by exposure to asbestos.dust.Diagnosis of Lung Diseases:Respiratory diseases may be investigated by performing one or more of the following tests1. Chest X-rays2. Pulmonary Function Tests3. CT Scan of the lungs4. Culture of micro-organisms from sputum or respiratory aspirates5. Bronchoscopy6. Biopsy of the lung or pleuraTreatment of lung Diseases:The treatment of the lung diseases depends on the types of diseases and the causes.TABLE OF CONTENTChapter 1 Lung DiseasesChapter 2 AsthmaChapter 3 BronchitisChapter 4 CoughChapter 5 Pleural EffusionChapter 6 PneumothoraxChapter 7 PneumoniaChapter 8 Chronic Obstructive Lung DiseaseChapter 9 Lung CancerChapter 10 Epilogue