Respiratory Flashcards
What is sarcoidosis?
Aetiology
Most commonly affects..?
Systems affected
systemic inflammatory disease characterised by development of non-caeseating granuloma in several organs (at least two)
unknown aetiology
Respiratory involvement (90%) + lymph nodes draining in lungs (diffuse parenchymal lung involvement may progress to irreversible fibrosis)
Skin - erythema nodosum
CT appearances of sarcoidosis
hilar + mediastinal lymphadenopathy
nodules along bronchi
ground-glass shadowing
parenchymal bands, cysts and fibrosis
stages of sarcoidosis in CXR signs
stage 0 - clear CXR
stage 1 - BHL
stage 2 - BHL + pulmonary infiltration (upper zone firbosis)
stage 3 - diffuse pulmonary infiltration
stage 4 - pulmonary fibrosis
Treatment for sarcoidosis
What kind of patient is this indicated?
1st line - cortiscosteroids
indicated with patients with:
- persisitent hypercalcaemia + hypercalciuria
- ophthalmological complications
- neurological complications
Methotrexate / azathioprine maybe used as an adjunct or alone if steroid sparing agents are required
immunosuppressive or anti-inflammatory treatments have only a limited role
What is sarcoidosis prognosis?
Good
resolution in most people 2 to 5 years
25% of people will develop residual fibrosis in lungs or elsewhere
most cause of disease related mortality are:
- lung
- cardiac
- neurological disease that is not reponsive to therapy
What is Goodpasture syndrome?
rare autoimmune disease characterised by the production of antibodies (anti-GBM) directed against the basement membrane of the kidneys and the lungs
attacking alpha-3 chain of type IV collagen
haemoptysis + glomerulonephritis
Mesothelioma
- cause
- pathology
- prognosis
associated with previous asbestos exposure
malignant condition of the pleura
- diagnosed based on histology of the pleura
poor prognosis
Pathology of bronchiectasis
symptoms
permanent and irreversible dilations of the bronchial walls
caused by - CF, immuned system deficiencies, TB
symptoms:
- high sputum production
- recurrent chest infections
- haemptysis (specific to bronchiectasis - tends to cause death by asphyxiation rather than exsanguination)
common - postnasal dip + chronic sinusitis (30%)
pathology of SIADH
associated risks with SIADH
common in what what kind of lung cancer?
inappropriate secretion of vasopressin (ADH) leading to overhydration of intracellular + extra compartments
dilutional hyponatraemia
low serum osmolality
high urine osmolality
risk of cerebral oedema
- drowsiness, lethargy, irritability, confusion + disorientation, coma
common in patients with small cell carcinoma (70% of cases of SIADH are found in cancer)
what is the treatment for SIADH?
risks assoicated with replacing sodium too rapidly
- Restrict fluids 700 to 1000ml
- Demeclocycline 600 to 1200mg
infusing hypertonic saline is hazardous - precipitating cardiac failure + cerebral oedema
if sodium replaced too quickly - risk of central pontine myelinolysis (CPM)
- sodium levels rise, water moves out of the cells
- cells dehydrate
- dehydrations damaged the nerve cells and the myeline sheath that surrounds them
what does CURB65 stand for?
what scorings relate to management?
Confusion
Urea > 7mmol/L
RR >30 p/min
BP <90/60 mmHg
>65
Score 0-1 = manage at home / PO Abx
Score 2-3 = manage in hospital (short stay)
Score 4-5 = admit and observe closely (ITU/ICU)
life threatening indicators acute exacerbation of asthma
PEFR < 33% best or predicted
O2 sats <92%
silent chest
cyanosis
cardiac arrhythmia / hypotension
confusion, coma, altered conscious
Severe indicators of acute exacerbation of asthma
PEFR 33-50% best or predicted
RR equal or >25 b/min
HR equal or >110 b/min
use of accessory muscles
O2 equal or >92%
side effects of methotrexate
pneumonitis
drug related pulmonary fibrosis
What respiratory conditions do NOT cause clubbing?
COPD
uncomplicated bronchitis
What paraneoplastic syndrome can occur in squamous cell carinoma?
tumour cells produce parathyroid hormone-related protein (PTHrP)
- it increases bone resorption + renal tubular reaborption of calicum (similar to PTH)
levels of PTH are suppressed by PTHrP mediated hypercalcaemia
PTHrP can be a useful tumour marker because its level reduce in response to effect treatment of the tumour
What paraneoplastic syndrome can occur in patients with small cell carcinoma?
70% of cases of SIADH associated with small cell carcinoma
