9 Respiratory System Disorders

Flashcards on Respiratory System Disorders based on lecture notes.

Bronchialatresia

Narrowing of bronchus

Hypoplasia of lung

Smaller than normal lung

Bronchogenic cysts

Contain much mucus

Bronchopulmonary sequestration

Portion of lung does not communicate with bronchial tree

Kartagener’s Syndrome (immotile cilia syndrome)

Defective cilia function

Neonatal respiratory distress syndrome (NRDS)

Deficiency of surfactant, alveoli collapse; atelectasis

Cystic fibrosis

CF gene causes production of abnormal viscid mucus, cannot be cleared from lungs; recurrent infections; bronchiectasis & haemoptysis; hyperinflation & pneumothorax; necrosis, scarring; pulmonary HT & cor pulmonale

Chronic Venous Congestion

↓ LV output → rupture of alveolar capillaries, haemorrhage, necrosis, fibrosis → brown induration

Pulmonary Oedema

Congestive heart failure, infections, gas inhalation, radiation → dyspnoea, hypostatic pneumonia

Pulmonary embolism

80% arise in deep leg veins → dyspnoea, tachycardia, shock → infarction/fatal “saddle embolus”

Pulmonary infarction

elderly/ post-operative/patients with heart failure → thromboemboli → dyspnoea/scarring/death

Pulmonary hypertension

Primary HT rare; Secondary HT due to lung, heart disease → dyspnoea, plexiform lesions

Chronic Obstructive Pulmonary/Airways Disease (COPD/COAD)

A disease state characterised by persistent airflow limitation that is not fully reversible → dyspnoea/SOB, cough, sputum

Emphysema

 size of alveolar spaces & loss of elastic recoil (distal to the terminal bronchiole)

Familial Emphysema

Due to inherited defect in 1-antiproteinase; Acquired: Smoking →  -1-antiproteinase → -1-antiproteinase cannot inactivate elastases released by neutrophils → elastases destroy elastic tissue in alveolar walls

Bronchiectasis

Permanent dilatation of bronchi & bronchioles → Recurrent cough, copious mucus Due to chronic infections, TB/sarcoidosis, smoking/scarring, dust inhalations, tumours, cystic fibrosis, immotile cilia syndrome

Chronic Bronchitis & Bronchiolitis

Mucous hypersecretion, inflammation of airways airway narrowing; Due to smoking, dust/fume inhalations, infections/inflammations

Bronchial Asthma

Reversible bronchospasm causing wheezing & excess mucus-mediated by Type I hypersensitivity

Extrinsic asthma

allergic/environmental triggers

Intrinsic asthma

exercise, stress, psychogenic triggers

Lobar pneumonia

Young adults; S. pneumoniae; whole lung lobe(s); 8 day course; resolution

Bronchopneumonia

Age extremes; Different flora; patchy lesions; irregular course; pus & fibrosis

Tuberculosis

Caseating granulomatous inflammation; airborne transmission of M.tuberculosis; tubercle formation

Viral Infections

Influenza, rhinovirus, coxsackievirus, echovirus, SARS coronavirus, CMV

Fungal Infections

Aspergillus spp, Cryptococcus spp, Candida albicans, Pneumocystis jiroveci (carinii)

Sarcoidosis

Idiopathic, granulomatous inflammation; in women ; immune anomalies; +ve Kveim-Siltzback skin test

Adult Respiratory Distress Syndrome (ARDS)

Diffuse alveolar damage due to septicaemia, major trauma, toxic smoke/fume inhalation, amniotic fluid embolism, DIC, radiation injury, chemotherapy; 70% die in acute phase

Byssinosis

cotton protein

Bagassosis

sugar cane refuse

Farmers’ lung

mouldy hay

Suberosis

cork dust

Anthracosis

Carbon; Cigarette smokers; Most harmless of inorganic

Silicosis

Silica; Quarry workers, stone masons; Predisposes to TB; COPD, RH problems

Silicoanthracosis

Carbon & silica; Coal workers; Results as for silicosis

Berylliosis

Beryllium; Miners, electronics industry; Lead to granulomas, COPD

Silicosiderosis

Silica & iron; Miners, iron ore workers; Predisposes to TB, lung malignancy

Asbestosis

Asbestos; Most harmful; Miners, building/automotive industries Lead to asbestosis, COPD, mesothelioma of pleura

Mesothelioma of the pleura

Exposure to asbestos; Highly malignant, death usual within 10 months of diagnosis.

Carcinoma of bronchus

Due to smoking, X-rays, -rays, Radon gas, asbestosis; Silicosiderosis; Mining of Ni, Cr. Central (~55%); Peripheral (~40%); Diffuse (~5%); Pancoast/Horner’s syndromes

Morphology of Carcinoma of bronchus

Squamous cell carcinoma (~ 50%)

Morphology of Carcinoma of bronchus

Small cell anaplastic ca. (“oat cell” ~20%, worst prognosis)

Morphology of Carcinoma of bronchus

Large cell anaplastic ca. (~ 10%)

Morphology of Carcinoma of bronchus

Adenocarcinoma (~ 15%)

Morphology of Carcinoma of bronchus

Alveolar cell carcinoma (~5%, best prognosis)

Staging of Carcinoma of Bronchus

TNM (Tumour TX,TIS,T1,T2,T3; Lymph node N0,N1,N2; Metastasis M0,M1); Av 5 yrsurvival <10%

Secondary tumours

Breast, bone, skin, kidney tumours commonly metastasize to lung