Bronchiectasis and Chronic Infection

Question 1

What are the risk factors for developing chronic pulmonary infection?

Answer 1

Abnormal host response (immunodeficiency, immunosuppression), abnormal innate host defence (damaged bronchial mucosa, abnormal cilia, abnormal secretions), repeated insult (aspiration, indwelling material).

Question 2

What type of immunoglobulin deficiencies cause respiratory infection?

Answer 2

IgA (increased acute, rarely chronic), hypogammaglobulinaemia (increased acute and chronic), CVID (common variable immune deficiency, recurrent infections), specific polysaccharide antibody deficiency (SPAD).

Question 3

What other immunodeficiencies can cause respiratory infections?

Answer 3

Hyposplenism, immune paresis (myeloma, lymphoma, metastatic malignancy), HIV.

Question 4

Give examples of immunosuppressive treatments.

Answer 4

Steroids, asathioprine, methotrexate, cyclophophamide, monoclonal antibodies (inflximab and etanercept - anti-TNFa, tiruximab - anti CD20, leflunamide), chemotherapy.

Question 5

What can damage bronchial mucosa?

Answer 5

Smoking, recent pneumonia or viral infection, malignancy.

Question 6

What syndrome causes abnormal cilia?

Answer 6

Kartenager’s syndrome, Young’s syndrome.

Question 7

What causes abnormal secretions?

Answer 7

Cystic fibrosis, channelopathies.

Question 8

What can lead to recurrent aspiration and indwelling material?

Answer 8

Recurrent aspiration - NG feeding regurgitated into trachea, poor swallow, pharyngeal pouch. Indwelling material - NG tube in wrong place, chest drain, inhaled foreign body.

Question 9

What are some forms of chronic infection?

Answer 9

Intrapulmonary abscess, empyema, chronic bronchial sepsis, bronchiectasis, CF.

Question 10

What is the clinical presentation of intrapulmonary abscess?

Answer 10

Indolent presentation (little or no pain), weight loss, lethargy, tiredness, weakness, cough, high mortality, usually preceding infection (pneumonia, post viral, foreign body).

Question 11

What are the possible preceding illnesses of intrapulmonary abscess?

Answer 11

Pneumonia (flu -> staph pneumonia -> cavitating pneumonia -> abscess), aspiration pneumonia (vomiting, lowered conscious level, pharyngeal pouch).

Question 12

What about the host immune response can cause intrapulmonary abscesses?

Answer 12

Hypogammaglobulinaemia, abscesses usually commonly failure of macrophages that need Ig to activate them.

Question 13

What are the pathogens in intrapulmonary abscess?

Answer 13

Bacteria: strep, staph (particularly post flu), e.coli, Gm-ves. Fungi: aspergillus.

Question 14

What are the bacteria that cause empyema?

Answer 14

Frequently aerobic organisms. Gm+ve: strep milleri, staph aureus (post op or hospital acquired [nosocomial], immunocompromised). Gm-ve: e.coli, pseudomonas, haemophilus influenzae, klebsiellae.

Question 15

How would you diagnose empyema?

Answer 15

Clinical suspicion (slow to resolve pneumoia, lateral chest film), CXR (persisting effusion, particularly if loculations visible), USS (preferred investigation, used in targeted sampling).

Question 16

In a PA CXR, what should you look for?

Answer 16

D sign.

Question 17

What are lateral CXRs useful in?

Answer 17

Small retro-diaphragmatic collections.

Question 18

What is the treatment for empyema?

Answer 18

IV antibiotics (broad spectrum, amoxicillin and metronidazole initially) then oral antibiotics (directed towards cultured bacteria, at least 14 days).

Question 19

What type of drains are preferred initially in empyema?

Answer 19

Small bore seldinger type drains.

Question 20

What is bronchiectasis?

Answer 20

Localised, irreversible dilation of the bronchial tree.

Question 21

Describe what happens to the bronchi involved in bronchiectasis?

Answer 21

The become dilated, inflamed and easily collapsible.

Question 22

What does bronchiectasis cause?

Answer 22

Airflow obstruction and impaired clearance of secretions.

Question 23

What is the clinical presentation of bronchiectasis?

Answer 23

Recurrent chest infections, recurrent antibiotic prescriptions, no response to antibiotics or short-lived response to antibiotics, persistent sputum production.

Question 24

How would you diagnose bronchiectasis?

Answer 24

Clinical: cough productive of sputum, chest pain, recurrent LRTIs. Radiological: HRCT (high resolution CT). Bronchiectasis looks like signet ring.

Question 25

What are the causes of bronchiectasis?

Answer 25

Bronchial obstruction, CF, Youngs and Kartanagers syndrome, ABPA (allergic bronchopulmonary aspergillosis), immunodeficiency, rheumatoid arthritis, bronchopulmonary sequestration, Mounier-Khun syndrome, yellow nail syndrome, traction bronchiectasis associated with pulmonary fibrosis. Idiopathic.

Question 26

What is the disease that has all the hallmarks of bronchiectasis but no bronchiectasis on HRCT?

Answer 26

Chronic bronchial sepsis.

Question 27

Who does chronic bronchial sepsis affect?

Answer 27

Often younger patients (mainly women involved in childcare), others are older with COPD or airways disease.

Question 28

What is the normal treatment for bronchiectasis or chronic bronchial sepsis?

Answer 28

Stop smoking, flu vaccine, pneumococcal vaccine, reactive antibiotics (send sputum sample, give antibiotics appropriate to most recent positive culture).

Question 29

What is the treatment for bronchiectasis/chronic bronchial sepsis when colonised with persistent bacteria?

Answer 29

Prophylactic antibiotics, nebulised gentamicin and colomycin, pulsed IV antibiotics, alternating oral antibiotics.

Question 30

What is the anti-inflammatory treatment of bronchiectasis/bronchial sepsis?

Answer 30

Low dose macrolide antibiotics have been shown to reduce exacerbation rates in bronchiectasis (particularly effective in pseudomonas colonised individuals).

Question 31

What is the prognosis for people diagnosed with bronchiectasis?

Answer 31

Recurrent infection, abscesses and empyema, colonisation.