Suppurative Lung Diseases PDF

Suppurative Lung Diseases ILOs At the end of this session, the student will be able to: Outline suppurative lung diseases groups. Explain Lung abscess: definition, types, clinical picture, investigations and treatment. Describe Bronchiectasis: definition, c...

Suppurative Lung Diseases ILOs At the end of this session, the student will be able to: Outline suppurative lung diseases groups. Explain Lung abscess: definition, types, clinical picture, investigations and treatment. Describe Bronchiectasis: definition, classifications, clinical picture and management. State causes of congenital bronchiectasis. Define Massive haemoptysis and state lines of treatment. Lung abscess Bronchiectasis Empyema with or without bronchopleural fistula I. Lung abscess Definition And Classification It is a localized suppurative lesion of lung parenchyma causing a rounded cavity with an air-fluid level in the chest x-ray and is not due to TB. Early in the acute phase of the diseases, there will be a nearly area of consolidation (pre-eruptive phase). Soon liquefactive necrosis occurs, and then there will be sudden expectoration of the pus with replacement of this pus by air, so giving an air - fluid level in the chest x-ray. If the lesion is persistent for a long time - more than 3 months - it will be described as chronic lung abscess. Lung abscess is classified into different types: 1- Post - Pneumonic Lung Abscess It occurs following necrotizing pneumonia e.g. staphylococcal pneumonia or klebsiella pneumonia, 2- Aspiration lung abscess It occurs secondary to aspirated foreign bodies. It is important to ask the patient about disturbances in his conscious state which may predispose to aspiration of any foreign body. 1  3- Malignant lung abscess Central necrosis in the tumour can result in the formation of lung abscess. The presence of the central bronchial obstruction will impair drainage of secretions and ends in distal infection which leads to the formation of peripheral lung abscess. 4- Post-traumatic lung abscess This can occur in an infected hematoma of the lung. 5- Septic pulmonary embolization. 6- Amoebic lung abscess It usually spread to the lung from amoebic liver abscess. Clinical Picture There is fever and the patient is very ill. Characteristically from the patient′s history there is sudden expectoration of a big amount of sputum when the abscess communicates with a bronchus. Such sputum is usually purulent. Clubbing may be present and clinical signs of consolidation e.g. bronchial breathing or crepitation or signs of cavity (cavernous or amorphic breathing) are found. Investigations Blood picture: the white cell count is increased. X - Ray chest: reveals rounded hydro - aerial shadow with a fluid level. Computed tomography demonstrates the abscess and shows any central masses. Sputum examination : culture and sensitivity to different antibiotics. 2  Bronchoscopy : it is used when there is suspicion of foreign body inhalation or endo - bronchial tumour causing bronchial obstruction. Staphylococcal pneumonia presenting as multiple lung abscesses in the P-A and lateral chest X-ray Treatment: This involves postural and bronchoscopic drainage. Drug treatment involves intensive antimicrobial therapy that is necessary to prevent further lung destruction. This is achieved through the identification of the organism by culture and selection of the proper antibiotic using an antibiogram. Penicillin G in big doses is the drug of choice with which to start. Initially two million units every six hours parenterally are given. Metronidazole 300 mg four times daily for anaerobic organisms. Surgical resections may indicated in specific chronic situations, e.g., the site of serious hemoptysis or failed medical treatment to control infection and toxemia. 3 Complications: Empyema is due to rupture in pleural space. Prolonged toxaemia and chronicity with fever, pleural pain and sweating. Severe and fatal haemorrhage. Metastatic brain abscess through pulmonary veins. Residual bronchiectasis. Amyloidosis in case of prolonged suppuration II. Bronchiectasis Definition And Classification Bronchiectasis is abnormal permanent dilation of subsegmental (bronchi). It is one of the groups of chronic suppurative lung diseases (other members of this group include chronic lung abscess and empyema with bronchopleural fistula). Bronchiectasis is classified into congenital and acquired bronchiectasis. I- Acquired bronchiectasis: Is usually secondary to the following disorders: 1. Atelectasis: This occurs secondary to bronchial obstruction. Such obstruction may be: intra-bronchial such as foreign bodies, endo-bronchial obstruction by neoplastic lesion, or extra-bronchial compression by enlarged lymph glands 2. Infection: Although atelectasis leads to infection as previously described, yet infection alone (even without atelectasis) can directly cause bronchiectasis through subsequent fibrosis which exerts traction on the bronchial wall (traction bronchiectasis). 3. Acquired immunodeficient state: This causes recurrent infections. It can occur in acquired immunodeficient syndrome (AIDS), multiple myeloma, chronic lymphatic leukemia, and lymphoma. II- Congenital bronchiectasis This includes: a- Immotile cilia syndrome which is better called dyskinetic cilia syndrome. The most important type of it is kartagar syndrome. b- Cystic fibrosis of the pancreas (mucoviscidosis). c- Overlap syndrome (young syndrome) which has combined features from the two previously mentioned congenital defects. d- Alfa -1 antitrypsin deficiency. 4  e- Bronchial cartilage deficiency e.g. william campbell syndrome. f- Macleod′S syndrome. g-Sequestrated lobe. h- Congential immunodeficient state e.g. congenital hypogamma - globulinemia Cystic Fibrosis It is a congenital disorder inherited by a recessive autosomal gene. The syndrome is characterized by high sodium content in the sweat (more than 60 or 70 meq /l) and high chloride in the sweat (more than 60 meq /l) such disturbance is due to abnormality of membrane transport to different ions. Mucoviscidosis affects the exocrine glands and is characterized by the presence of viscid mucus secretion hence its name mucoviscidosis. Different organs are affected result in the following organ disorders: ✓ Intestine: Intussusception, Meconium Ileus. ✓ Pancreas: Diabetes Mellitus and Steatorrhea Secondary To Pancreatic Lipase Deficiency. ✓ Kidney: Amyloidosis ✓ Liver And Gall Blander: Gall Stones, Biliary Cirrhosis. ✓ Infertility (Sterility): From Obstructive Azospermia. ✓ Pulmonary manifestations of cystic fibrosis include recurrent bronchitis, bronchiolitis, atelectasis and bronchiectasis Immotile (dyskinetic) cilia syndrome It is a disease of the respiratory tract ciliated cells and spermatozoa leading to respiratory tract infection and male sterility. The most common pathological abnormality is the deficiency of the dynein arms of the respiratory tract cilia as well as of spermatozoa. Half of the persons with immotile cilia syndrome have situs inversus or dextrocardia, sinusitis, or underdeveloped frontal sinus and hence have "kartagener′s syndrome". Macleod′S syndrome It is unilateral emphysema due to localized bronchiolitis or bronchitis and is one of the causes of unilateral Hyper translucency in chest x-ray. It is also observed that the pulmonary artery on the affected side is small. This is attributed to the early changes in the bronchopulmonary system. Sequestrated lobe It is a congenital abnormality by which a portion of the lung (usually of the left lower lobe) becomes isolated i.e. sequestrated from the rest of lung during development. Occasionally the sequestrated part is not included in the lung and in this situation it is described as extralobar sequestration. 5 However, The Isolated Segment Is Most Often Included Within the Lower Lobe (Intralobar Sequestration). Infection May Reach It Through the Blood Stream. Once infection occurs a communication between such sequestrated lobe and the bronchial tree occurs with recurrent expectoration of such suppurative secretions There is always an abnormal blood supply to the sequestrated area, usually from the aorta. Such abnormal blood supply should be demonstrated by angiography and clamped before surgical resection of this sequestrated lobe. Alpha 1 - Antitrypsin deficiency It is a congenital deficiency of a protective protein that antagonizes the action of protease enzymes released from the rupture of different cells. Such enzymes cause proteolysis of the lung tissues. N.B: Other miscellaneous disorders sometimes associated with bronchiectasis include: Ehlers-Danlos syndrome and Marfan′s syndrome (disorders of connective tissues). Trachio-bronchomalacia. Yellow nail syndrome: syndrome of primary lymphoedema, yellow nails, and pleural effusion Collagenic diseases: as rheumatoid arthritis and systemic lupus erythematosus Clinical Picture There is chronic expectoration of big amount of purulent sputum (yellowish, greenish or bluish) that is usually offensive due to associated anaerobic infections e.g. by bacteroids. The sputum may be blood tinged but frank haemoptysis can occur. Bronchiectasis usually affects the basal segments of both lower lobes. However, post-tuberculous bronchiectasis is usually located in the upper lobes. Complications of bronchiectasis include massive haemoptysis, recurrent pneumonia, empyema, lung abscess, and brain abscess. Investigations 1-Chest x-ray, reveals the presence of microcystic shadows i.e. honeycomb appearance 2-Bronchogram is made by passing a catheter in the tracheobronchial tree and then injecting a radio - opaque dye. Bronchiectasis is classified as pathological into: Cystic (saccular) bronchiectasis which ends by blind sacs. This type usually has the worst prognosis Massive haemoptysis can occur from angiomatoids which are the site of intrapulmonary shunts. 6  Cylindrical bronchiectasis Fusiform (varicose-like) bronchiectasis with areas of constrictions. 3- High-resolution computed tomography (HRCT): it is now the most important diagnostic investigation and it replaced bronchogram in the diagnosis of bronchiectasis In HRCT scan bronchiectasis appears as microcystic shadows i.e. honeycomb appearance 4- Pulmonary function tests (PFT): these levels of obstructive pulmonary dysfunction or combined obstructive and restrictive dysfunction 5-ECG: P-Pulmonary may be seen with or without other criteria of right ventricular hypertrophy (cor pulmonale). 6-Other special investigations: Analysis of sodium chloride in the sweat in cystic fibrosis. Bronchoscopy is indicated if there is the possibility of foreign body aspiration or bronchial adenoma. Estimation of immunoglobulins, alfa one antitrypsin , collagenic profile DD Chronic bronchitis T.B. Lung abscess Other causes of haemoptysis Complications Fatal haemoptysis Brain abscess Progressive pulmonary insufficiency low PaO2, high PaCO2, Cor- pulmonale Amyloidosis Treatment 1-Antibiotics; more than one is beneficial + anti-anaerobes) are important to control the infective episodes of such suppurative disease. 2-Expectorants and mucolytics (as described in treatment of COPD). 3-Postural drainage. 4-Bronchodilators if associated bronchospasm. 5-Management of massive haemoptysis which is a serious complication of bronchiectasis 7  ▪ Massive haemoptysis is defined as the coughing of about 600ml or more of blood in a day. However, other references considered hemoptysis to be massive if < 200 ml/day is coughed , moderate if 200ml/day, and mild if it is less than 20ml/day. ▪ Important items in the management of hemoptysis include patient reassurance, complete bed rest with the bleeding site down and the use of antitussive e.g. codiene , 30-60 mg every 4-6 hours. However, care must be taken not to overdose. A blood transfusion may be required. ▪ Any associated bleeding diathesis or coagulopathy must be corrected when possible. In severe uncontrolled haemoptysis, intubation maybe done with a carlens tube, which is a double-lumen endotracheal tube. This tube allows ventilation of the good lung with simultaneous isolation and suctioning of the bleeding lung. ▪ In endobronchial tamponade, the bronchus is occluded with a fogarty catheter. The catheter is left in place for 1-2 days. Bronchial artery embolization is another line to stop massive haemoptysis. Aortography is performed first. After the bleeding vessel is identified and cannulated, ▪ Embolization of this bronchial artery is carried out by injection gel foam. Before bronchial artery embolization, be sure that the spinal arteries are not abnormally arising from that artery otherwise infarction of the spinal cord with subsequent paraplegia will occur. Lastly, surgical resection is another important line of management of this serious condition. 6- Surgery in the form of surgical resection of the bronchiectatic lobe may be indicated in localized bronchiectasis or uncontrolled massive haemoptysis. However, it should be emphasized that the treatment of bronchiectasis is mainly medical. 8