RESPIRATORY - TB, Lung cancer, Pneumothorax and Pleural effusions Flashcards
Peak incidence lung cancer
65 y/o
M:F lung cancer
3:1
RF lung cancer
Smoking
Passive smoking
Urban living
Occupational exposure
Which type of lung cancer do occupational exposures mostly lead to
Adenocarcinoma
% of lung cancer in regards to location
70% centrally (main bronchi/hilum)
30% peripherally
What are the 4 types of lung cancer
Squamous cell carcinoma (40-50%)
Adenocarcinoma (20-40%)
Small cell anaplastic carcinoma (20-30%)
Large cell anaplastic carcinoma (10%)
Where does squamous cell lung carcinoma arise form?
Sqamous metaplasia of pseudostratified ciliated columnar epithelium
What is SCC usually in response to
Cigarette smoke exposure
Where in the lungs do SCC;’s tend to arise
Central + close to carina
What substance can SCC’s secrete + what Sx does this lead to
PTH
Hypercalcaemia
Diagnosis SCC
CXR
Sputum cytology
Prognosis SCC
Slow growing
and may be resectable
Where do adenocarcinomas of the lung tend to arise
Peripherally 2/3
Areas of previous lung scarring
Why are non-smoking women at risk of developing lung adenocarcinoma
Because they have a high incidence of growth factor receptor
Which type of lung adenocarcinoma is associated with a better prognosis?
Bronchoalveolar carcinoma
Another name for small cell anaplastic carcinoma
Oat cell carcinoma
Where are small cell carcinoma’s usually located
Centrally
Spread small cell carcinoma
Grow rapidly
+ often mets at diagnosis
Origin small cell carcinoma
From bronchial epithelial
Which DDx into neuroendocrine/Kulchitsky cells
What do Kulchitsky cells do
Express markers + secrete ADH + ACTH
Small cell carcinoma can lead to which MG-like syndrome?
Eaton-Lambert syndrome
Sx Eaton-Lambert syndrome (5)
Scapular/pelvic girdles Reduced tendon reflexes Dry eyes Sexual impotence Neuropathy
Prognosis Eaton-Lambert syndrome
usually gets better w/ usage
What are large cell anaplastic carcinomas
Show SCC/adenocarinomatous origins
But not DDx enough to be classified
Where in lung do large cell anaplastic carcinomas present
Centrally
Prognosis large cell anaplastic carcinomas
Poor
Widely disseminated @diagnosis
Which grade Non-small cell lung cancers are operable?
T1NO - T3N2
Early catching non-small cell lung cancer 5y survival rate
55-67%
PS Lung cancer (7)
Persistent cough Haemoptysis Dyspnoea Chest pain B Sx Chest infections W loss
O/E - lung cancer (6)
Clubbing Cahexia Signs anaemia Hypertrophic pulmonary OA Chest signs - collapse/consolidation/effusion Signs of mets
What is hypertrophic pulmonary OA due to?
Paraneoplastic syndrome
= Clubbing + painful periostheitis of small joints of hands
Paraneoplastic syndromes which can arise due to lung cancer (5)
Hypertrophic pulmonary OA Lambert-Eaton syndrome SIADH 2' Cushings HyperPTH
Local invasion issues caused by lung cancers (7)
Rec laryngeal nn palsy Phrenic nn palsy SVC obstruction Pancoast syndrome Pericarditis Pericardium --> effusion/AF Oesophageal fistulas/dysphagia
When are phrenic nn palsies asymptomatic?
If unilateral
S+S of SVC obstruction
Raised JVP
Raised arm BP/swelling
Facial swelling
Headache
What is Pancoast syndrome
Malignant neoplasm of lung apex –> destructive lesions of thoracic inlet
Sx Pancoast syndrome (4)
Horners syndrome
Shoulder pain R along ulnar forearm + hand
Atrophy hand/arm mm
Oedema b/c BV occlusion
mets lung cancer (4)
Brain
Bone
Liver
Adrenal gland
What condition can Adrenal mets PS as
Addison’s
Skin conditions indicating lung cancer (2)
Acanthosis nigricans
Dermatomyositis
DDx lung mass
Granuloma
Aspergilloma
Ix lung cancer (10)
FBC (anaemia/polycythaemia) LFTs - mets U+E - hypercalcaemia/hyponatraemia CXR Sputum/pleural fl cytology Staging CT Biopsy CT via bronchoscopy Pulmonary fct tests PET scan (mets)
Why use pulmonary function tests when investigating lung cancer?
For planning surgery
If a lung cancer lesion is hidden by the heart, what should you look for on CXR
hilar lymphadenopathy
How do children present with 1’ TB (2)
Enlarged mediastinal LN + cough
Natural Hx TB
1 - inhal TB
2 TB –> alveoli - taken up by macrophages + local consolidation occurs
3 –> Ghon focus (infective focus) –> nodes –> 1’ complex
4 -Dissemination occurs –> foci at distant site (bronchi/pleura/pericardium)
5 - Further spread limited by CMI - IV HS
6 - Foci heal by fibrosis + calcify
7 - Viable bacteria remain walled off –> latent TB
In what ways can 1’ TB come symptomatic (4)
Ghon focus can erode through visceral pleura –> TB pleurisy/pleural effusions
Enlarge LN can –> bronchial obstruction + collapse
LN can erode into bronchus + rupture –> TB bronchopneumonia
Enlarging LN can erode into vessels –> military dissemination (lung) or systemic dissemination
What is post-primary TB?
M. TB reinfection in tuberculin-sensitive individuals
How can post-primary TB occur? (2)
From exogenous sources
Or reactivation from healed 1’ complex (> common)
pathology post-primary TB
Lung: classical apical lesion = assmann focus w/ destruction lung parenchyma –> cavitation
Lesion may heal w/ fibrosis or will progressively enlarge
Early Sx TB
B Sx Hence malaise Night sweats Anorexia W loss
Later Sx TB
Productive mucoid cough
Repeated small haemoptysis
PLeural pain
Pneumonia/Pleural effusion
O/E TB
Fever
Apical crepitations
Clubbing in advanced disease
What % of the worlds population is infected by M TB
1/3
What are the greatest RF for being infected w/ TB
Social deprivation Non-white ethnicity Alcohol dependence HIV Increasing age Overcrowding Those on immunosuppressive therapies
Ix TB (6)
Sputum samples x3 incl 1 monring
Microscopy
PCR
Lowenstein Jensen culture (gold standard)
CXR
Bronchoscopy + biopsy if culture negative
Mantoux test >5mm
= positive in immunosuppressed indiv or those w/ prior TB/recent contacts
Mantoux test >10mm
+ve in those w/ RF for YB
Mantoux test >15mm
Positive in any individual
What should every TB pt be screened for before starting Tx
HIV
Hep B/C
Examples of extrapulmonary features of RB
Lymphatic TB Potts Ileocecal TB Scrofulderma Meningism UG Pericardium Adrenal glands
What is Pott’s disease
Spinal involvement of TB –> chronic back pain
If TB affects the pericardum, what is it associated with (4)
AF
Elevated JVP
Kussmaul’s sign
Pulsus paradoxus
What condition does TB mimic if it affects the adrenals
Addisons
Cutaneous TB e.g.s (2)
Erythema nodosum
Lupus vulgaris
Def pneumothorac
A tear in the lung –> air leaking out into pleural space
PS Pneumothorax
Asymp in young pt if small
Or PS w/ sudden onset unilat pleuritic pain
+ progressive breathlessness
1’ spontaneous pneumothorax - M:F
6:1
Cause of primary spontaneous pneumothorax
Rupture of apical bleb/bulla
B/C congenital defects in CT alveolar walls
Tall + thin pt
Main cause of 2’ pneumothorax
COPD
Rarer causes of 2’ pneumothorax (4)
Bronchial asthma
Carcinoma
Lung abscess
Severe fibrosis (CF)
What % pt w/ 2’ pneumothorax have recurrence
1/3
2 types of non-spontaneous pneumothorax
Traumatic pneumothorax
Iatrogenic pneumothorax
Mechanism of a tension pneumothorax
Intrapleural pressure = high
Due to P differences air = sucked into pleural space during inspiration, but not expelled during exp
Hence: lung deflates + vv return to heart decreases –> cardiac compromise
Who gets tension pneumothorax
Patients on +ve P ventilation
Features suggesting tension pneumothorax (7)
Tracheal deviation AWAY from the affected side Signs haemodynamic compromise \+/- distended neck vv Reduced expansion Increased resonance on percussion Decr breath sounds Decr vocal resonance
Ix for pt w/ suspected pneumothorax
Expiratory CXR
ABG
Mx tension pneumothorax
100% O2
Needle decompression - insert large bore cannula into 2nd ICS, MCL
CXR
Insert chest drain + aspirate if >2cm
How does needle decompression work for Mx of pneumothorax
Large bore cannula into 2nd ICS MCL on side of suspected lesion
Partially filled w saline
Pull back on syringe to allow air to bubble out until a chest drain can be instered
Empyema
Accumulation of pus, due to infection
Chylothorax
Accumulation of lymph due to thoracic duct leakage
Haemothorax
Accumulation of blood due to trauma
Why does a transudate effusion occur?
Due to increased HSP or decreased oncotic P
Why does an exudate effusion occur>
Increased capillary permeability
Causes of transudate pleural effusion (4)
Cardiac failure
Liver failure
Renal failure
Peritoneal dialysis
Causes of exudative effusion (8)
Bacterial pneumonia TB Neoplasms - lung 1/2' Mesothelioma PE RA/SLE Pancreatitis Subphrenic abscess
PS pleural effusion (3)
Asymp
Dyspnoea
Pleuritic pain
O/E Pleural effusion (5)
Decr chest expansion Stony dull to percussion Decr breath sounds Reduced vocal resonance Mediatinal deviation if massive
What is an empyema caused by?
Bacterial invasion of the pleural space, either by spreading an exudate effusion from adjacent pneumonia or by direct innoculation
PS empyema
Fever + signs pleural effusion
Aspirate empyema (5)
Yellow Turbid pH <7.2 Low glucose High LDH
Mx empyema (2)
IV Abx
CHest drain
Def Pleurisy
Inflammation of the pleura (usually due to an infection)
Ix pleural effusion (5)
CXR USS Aspiration Pleural tap Pleural biopsy
At what volume effusion can a chest xray begin to ID
300ml
Why is USS recommended in effusion
To guide aspiratoin
What 4 things happens to the aspirate from an effusion
–> microbiology for MCS
Clinical chemistry - protein/LDH/glucose
Cytology
BG machine for pH
Featues of an exudate aspirate (2)
Protein >30g/L
LDH >200
Features of a transudate aspirate (2)
LDH <200
Protein <30
When aspirate is borderline, how to ddx from transudate and exudate
1 positive element of lights criteria - exudate
When is a pleural biopsy useful in effusions
Abrams needle
When DDxc malignant effusions + TB
Mx effusion if fl is purulent/turbid or pH <7.2
Chest drain + consider ABx
Mx underlying cause
