Flashcards in Chronic pulmonary Infection Deck (59)
What are the possible diagnoses for a patient with the following symptoms:
* Shadow on CXR
* Weight loss
* Persistent sputum production
* Chest pain
* Increasing shortness of breath
* Lung Cancer
* Intrapulmonary abscess
* Cystic Fibrosis
What are risk factors for developing chronic pulmonary infection?
Abnormal host response
* Immunodeficiency (congenital, acquired)
* Immunosuppression (drugs, malignancy)
* Abnormal innate host defence (damaged bronchial mucosa, abnormal cillia, abnormal secretions)
* Repeated insult (aspiration, indwelling material)
What can cause immunodeficiency?
* Immunoglobulin deficiency
* Immune paresis
What are different types of immunoglobulin deficiency?
* IgA Deficiency: common, increased risk of acute infections, rarely chronic infections
* Hypogammaglobulinaemia: rarer, increased risk of acute, and chronic infections
* CVID: commonest cause of immunodeficiency, recurrent infections
* Specific Polysaccharide Antibody Deficiency
How can smoking cause immunosuppression?
Abnormal cilia beat
What can causes aspiration?
NG tube down trachea rather than oesophagus
What is Specific Polysaccharide Antibody Deficiency (SPAD)?
Inability to develop antibodies against polysaccharide, so cannot resist certain bacteria
Why is hypo-splenism dangerous?
If no spleen, cannot produce polysaccharide antibodies
What is immune paresis?
Immune system goes into paretic state due to things like myeloma, lymphoma and metazoic malignancies
Why is immunosuppression common?
Due to increased use of immunosuppressant drugs
What are examples of immunosuppressant drugs?
* Monoclonal antibodies (Infliximab, etanercept: TNFa, Rituximab: CD20, Leflunamide)
What factors can damage bronchial mucosa?
* Recent pneumonia, or viral infection (‘Flu)
What conditions can lead to abnormal cillia?
* Kartenager’s Syndrome
* Youngs Syndrome
What conditions cause abnormal secretions?
* Cystic fibrosis
What are causes of recurrent aspiration?
* NG feeding
* Poor swallow
* Pharyngeal pouch (collects food, etc)
What are causes of indwelling material?
* NG tube in the wrong place
* Chest drain
* Inhaled foreign body (peanut, chicken bone, piece of coal, etc)
What are forms of chronic respiratory infection?
* Intrapulmonary abscess
* Chronic Bronchial Sepsis
* Cystic Fibrosis and other oddities
What are clinical features of intrapulmonary abscesses?
* Indolent presentation (no pain)
* Weight loss common
* Lethargy, tiredness, weakness
* Possible sputum
Why is treatment for intrapulmonary abscesses vital?
High mortality if not treated
What are causes of intrapulmonary abscesses?
Usually a preceding illness of some sort
* Pneumonic infection
* Post viral
* Foreign body
What are preceding illnesses of intrapulmonary abscesses?
(Remember ‘Flu -> Staph Pneumonia -> Cavitating Pneumonia -> Abscess)
* Lowered conscious level
* Pharyngeal pouch
Poor host immune response
What pathogens cause abscesses (stemming form pneumonia)?
* Staphylococcus (Particularly post ‘flu)
* E-Coli – normally in bowel but can present in chest to cause pneumonia
* Gram Negatives
What can multiple abscesses on a CXR be indicative of?
Bacteraemia - bloot infection
What are causes of septic emboli?
* Right sided endocarditis
* Infected DVT – once infected travel to lungs
* Intravenous drug users
Why are intravenous drug users at risk of septic emboli and abscesses?
* Inject into groin – blood clot due to repeated trauma to the vien
* Leads to DVT
* Then Infection
* Then PE + Abscesses
Why are abscesses caused by PE's so dangerous?
* Very high mortality - 75%
* Abscesses sit close to pulmonary vessels – if abscess erodes into pulmonary artery, loss of blood (exsanguination)
What is empyema?
Pus in the pleural space
What are causes of empyema?
* 57 % of all patients with pneumonia develop empyema (commonest cause)
* Remainder are “Primary Empyema”, often iatrogenic, many idiopathic
What is the mortality of empyema?
* High mortality
* As high as severe pneumonia
* > 20 % of all patients with empyema die