228: Fungal disease

Question 1

what does CD4 do?

Answer 1

communicate T cells with B cells

Question 2

what is hypersensitivity pneumonitis?

Answer 2

heavy exposure to proteins forms an immunce complex and cell mediated hypersensitivity ( type 3 and 4)

Question 3

immune cell of a type 3 hypersensitivity?

Answer 3

IgG

immune complexes trigger complement.

Question 4

immune cells of a type 4 hypersensitivity?

Answer 4

Th1, Th2, cytotoxic T lymphocytes.

t lymphocytes drive macrophages ( tissue damage)

Question 5

symptoms of hypersensitivity pneumonitis

Answer 5

dysnoea, cough, fever, flu like symptoms (4-6h after exposure)

Question 6

obstructive pulmonary picture?

Answer 6

low FEV1

Question 7

restrictive pulmonary picture?

Answer 7

low FVC

Question 8

diagnosis of hypersensitivity pneumonitis :

Answer 8

restrictive lung function
serum antibody precipitins 
high lymphocyte count in bronchiolar lavage
ground glass infiltrates on CT
granulomas and inflamed broncioles

Question 9

treatment of hypersensitivity pneumonitis?

Answer 9

oral steroids initially if still not controlled add a DMARD (disease modifying anti-rheumatic drug) cyclophosphamide.

Question 10

what is aspergillus?

Answer 10

a mould that exists as hyphae in the body.
in asthmatics/CF it can cause allergic bronchopulmonary aspergillosis.
in immune compromised it will invade blood vessels nad tissues outside the lung.

Question 11

what is allergic broncho pulmonary aspergillosis?

Answer 11

a type 3 (immune complex) and 4 (cell mediated) hypersensitivity reactions

fever cough dyspnoea, worsening of asthma, coughing up casts.

Question 12

ABPA (allergic broncho pulmonary aspergillisis) treatment?

Answer 12

long term antifungal therapy plus oral steroids

Question 13

what is an intra-cavitary aspergilloma?

Answer 13

a fungus ball ( mycetoma)

the hyphae release oxalic acid and blood vessel erosion leads to haemoptysis.

Question 14

treatment of an intracavity aspergilloma

Answer 14

antifungals are not good because its not systemic.
surgical resection
bronchial artery embolisation

Question 15

what can make a person neutropaenic?

Answer 15

AIDS, steroids, uncontrolled DM, chemo

Question 16

what is invasive aspergillosis?

Answer 16

in immunocompromised aspergilla gets systemic.
lung infarcts due to abundant hyphae
vessels plugged by fibrin
halo sign on blood film ( sign of oxalic acid degrading blood vessel)

Question 17

diagnosis of invasive aspergilloma ?

Answer 17

fungal hyphae in sputum and blood. serology may be negative due to immune supression.

Question 18

Treatment of invasive aspergilloma?

Answer 18

amphotericin and Flucytosine

Question 19

how does aspergillus cause cancer?

Answer 19

it produces aflatoxin which causes hepatocellular carcinoma.

Question 20

what can ground glass consolidation be a marker of?

Answer 20

hypersensitivity pneumonitis