Lung Pathology Flashcards
what is asthma
chronic inflammatory disorder of the airways
features of asthma
paroxysmal bronchospasm
wheeze
cough
variable bronchoconstriction - reversible
histology in asthma
mucosal inflammation and oedema
hypertrophic mucous glands and mucous plugs in brochi
what is atopic asthma?
type I hypersensitivity reaction
causes of atopic asthma
dust
pollen
animal products
cold, exercise, resp infections
persistent or irreversible changes in atopic asthma?
bronchiolar wall smooth muscle hypertrophy
mucus gland hyperplasia
respiratory brochiolitis leading to centrilobular emphysema
who gets atopic asthma
children and young adults
what is bronchiectasis
permanent dilation of bronchi and bronchioles caused by destruction of the muscle and elastic tissue
cause of bronchiectasis
infections
signs/symptoms of bronchiectasis
cough, fever, copious foul smelling sputum
predisposing conditions to bronchiectasis
CF
primary ciliary dyskinesia, Kartagener syndrome
bronchial obstruction - tumour, foreign body
lupus, RA, IBD, GVHD
complications of bronchiectasis
pneumonia
septicaemia
metastatic infection
amyloid
what is COPD
combination of chronic bronchitis and emphysema
cause of COPD
chronic irritation
smoking
air polution
what is the pathenogenesis of chronic bronchitis
mucous gland hyperplasia
seconday infection by low virulence bacteria
chronic inflammation - causes wall destruction and weakness = emphysema
most common emphysema
centrilobular
symptoms of COPD
dyspnoea - progressive and worsening
what is interstitial lung disease
diseases of pulmonary connective tissue
is interstitial lung disease restrictive or obstructive?
restrictive
what happens in interstitial lung disease
increased tissue in alveolar-capillary wall
inflammation and fibrosis
decreased lung compliance
increase diffusion distance
what is acute interstitial lung disease
diffuse alveolar damage - death of type 1 pneumocytes form hyaline membranes
adult respiratory distress syndrome: shock, trauma, infections, smoke, toxic gases
what is chronic interstitial lung diseases?
dyspnoea increasing for months to years
signs of chronic interstitial lung disease
clubbing, fine crackles, dry cough
examples of chronic interstitial lung diseases
idiopathic pulmonary fibrosis
many pnemoconioses
sarcoidosis
collagen vascular diseases
which lobes most severly affected in PF
lower lobes
what is sarcoidosis
non-caeseating perilymphatic pulmonary granulomas, then fibrosis
which nodes are usually involved in sarcoidosis
hilar nodes
which other organs may be affected by sarcoidosis
skin, heart, brain
who gets sarcoidosis
young adult females
what causes pneumoconioses
inhaled dusts
what size are the dust particles
<3 micrometres
what is silicosis
silica sand and stone dust kills phagocytosing macrophages
fibrosis and fibrous silicotic nodules
possible TB reactivation
what is hypersensitivity pneumonitis
extrinsic allergic alveolitis
what is the antigen in farmer’s lung
actinomycetes in hay
what is the antigen in pigeon fanciers lung
pigeon antigens
what is the effect of hypersensitivity pneumonitis
peribronchiolar inflammation with poorly formed non-caeseating granulomas extends alveolar walls
repeated episodes = interstitial fibrosis
what is cystic fibrosis
inherited multiorgan disorder of epithelial cells affecting fluid secretion in exocrine glands and the epithelial lining of the respiratory, GI and reproductive organs
characteristics of CF
broncioles distended with mucous
hyperplasia mucus secreting glands
repeated infections
bronchitis and bronchiectasis
effect of CF in exocrine gland
ducts plugged by mucus
atrophy and fibrosis of gland
impaired fat absorption, enzyme secretion, vit deficiencies
effect of CF in small bowel
mucus plugging
effect of CF in liver
plugging of bile cannaliculi - cirrhosis
effect of CF in salivary glands
similar to pancreas: atrophy and fibrosis
95% of males are …
infertile
diagnosis of CF
sweat test
treatment of CF
ivacaftor
mucolytics
heart/ lung transplants
most common type of primary lung cancer
carcinomas
most common lung carcinoma
adenocarcinoma
second most common lung carcinoma
squamous cell carcinoma
which kind of tumour is seen in HIV/AIDS patients
primary lung lymphomas
what are the most common secondary lung tumours
carcinomas from various sites e.g. breast, GI, kidney
epidemiology of lung cancer
most common cause of cancer death in UK
risk factors of lung cancer
smoking
5 year survival of lung cancer
5-10%
causes of lung cancer
smoking
occupational/ industrial hazards - asbestos
radiation - mines in which there is radon
lung fibrosis
genetic mutations in lung cancer
EGFR, KRAS, ALK
where do lung mets go
brain
bone
pleura
liver
local effects of lung tumours
ulceration and bleeding - haemoptysis consolidation symptoms of pneumonia pleural effusion chest wall/ rib pain recurrent laryngeal nerve - hoarseness horner's syndrome dysphagia
what is lymphangitis carcinomatosa
lymphatics within lung are diffusely involved by tumour
what makes up the visceral pleura
connective tissue
mesothelium
what makes up the parietal pleura
mesothelium
connective tissue
what should a normal mesothelium look like
single layer of cells
secrete hyaluronic acid - lubricates movement
what is pleural effusion
excess fluid in the pleural cavity - serous fluid
pus in pleural effusion
empyema or pyothorax
blood in pleural cavity
haemothorax
bile in pleural cavity
chylothorax
air in pleural cavity
pneumothorax
types of pleural effusions
transudates
exudates
features of transudate pleural effusions
high vascular hydrostatic pressure
low capillary oncotic pressure - hypoalbuminaemia - hepatic cirrhosis, nephrotic syndrome
features of exudate pleural effusions
inflammation with/without infection
neoplasms either primary or secondary
symptoms of pleural effusions
breathlessness - effusion compresses the lung
little/no pleuritic pain - visceral and parietal pleura are not in contact
signs of pleural effusion
dull percussion
reduced breath sounds
investigations of pleural effusion
imaging - ultrasound, CXR, CT scan
treatment of pleural effusion
aspiration with a needle and syringe - ultrasound
reaspirate if the fluid reaccumulates
most common malignant pleural cancer
mesothelioma
secondary malignant pleural cancers
carcinomas - breast, lung
what is malignant mesothelioma
a neoplasm of the mesothelial cells that line serous cavities
commoner in which gender?
men
early malignant mesothelioma
a small tumour can produce a large pleural effusion
how can mesothelial cells and epithelial cells be differentiated?
express different antigens
can be identified by immunostaining
causes of malignant mesotheliomas
asbestos
thoracic irradiation
BAP1 mutations
what is asbestos
fibrous metal silicates
which form asbestos is the most oncogenic
amphiboles - particularly crocidolite
what is asbestosis
interstitial pneumonia-like progressive pulmonary interstitial fibrosis caused by high level exposure to asbestos dust
characteristics of asbestosis
fibrosis of alveolar walls impairs gas exhange and lung expansion
pleural asbestos-related diseases
pleural effusion
parietal pleural fibrous plaques
diffuse pleural fibrosis
malignant mesothelioma
lung asbestos related diseases
asbestosis
lung carcinoma
skin asbestos related diseases
asbestos corns
differential diagnoses for sore throat
pharygitis
acute tonsillar pharyngitis
infectious mononucleosis (EBV)
epiglottitis
most common causes of pharyngitis and tonsillar pharyngitis
viruses: rhinovirus coronovirus parainfluenza influenza (A and B) adenovirus
bacteria:
group A strep (strep pyogenes)
Rare: n. gonorrhoeae, HIV-1, c.diptheriae
what are the centor criteria
tonsillar exudate
tender anterior cervical lymphadenopathy
>38
absence of cough
cause of infectious mononucleosis
EBV
who get infectious mononucleosis
teenagers
triad of symptoms in infectious mononucleosis
fever
tonisillar pharyngitis
cervical lymphadenopathy
what is epiglottitis
inflammation of structures above glottis
most common cause of epiglottitis
H. Influenzae type b
management of acute epiglottitis
significant mortality and morbidity
secure airway and oxygenation
treatment for epiglottitis
IV antibiotics
analgesia
inform public health
what is otitis externa
inflammation of the external ear canal presenting with otalgia, pruritus and non-mucoid ear discharge
what is acute OE
range in severity - mild > necrotising
unilateral
most common causative agent of acute OE
pseudomonas aeruginosa and s.aureus
what is malignant OE
spreads to skull base
who gets malignant OE
elderly diabetic or immunocompromised
what is otitis media
middle ear inflammation
what is uncomplicated acute OM
mild pain <72 hrs
no systemic symptoms
<39
no discharge
complicated acute OM
severe pain perforated ear drum purulent discharge bilateral infection mastoiditis
organisms that cause OM
s. pneumoniae
h. influenzae
what is mastoiditis
infection of mastoid bone and air cells
what is pneumonia
infection affecting the most distal airways and alveoli
formation of inflammatory exudate
what are the two anatomical patterns of pneumonia
bronchopneumonia - patchy distribution
lobar pneumonia - large part or entirety of lobe
cause of lobar pneumonia
s. pneumoniae
what is hospital acquired pneumonia
> 48hrs after hospital admission
organism in Ventilation acquired pneumonia
pseudomonas
organism in aspiration pneumonia
anaerobes
typical causative organisms of CAP
s. pnemoniae
h. influenzae
m. catarrhalis
s. aureus
klebsiella
atypical causative organisms of CAP
m. pneumoniae
legionella pneumophilia
chlamydophilia pneumoniae
chlamydophilia psittaci
what is used to assess severity of CAP
CURB score confusion urea - >7mmol/l resp rate - >30 BP - systolic <90, diastolic <60 age >65
recommended tests for all moderate-severe CAP based on CURB65 score
sputum culture blood culture pneumococcal urinary antigen legionella urinary antigen PCR serology for viral pathogens, M. pneumoniae, Chlamydiophilia sp.
complications of pneumonia
pleural effusion
empyema
lung abscess
causes of viral pneumonia in adults
influenza A and B
Adenovirus
Varicella zoster virus
causes of viral pneumonia in children
RSV
parainfluenza
pnemonia in immunocompromised host
measles HSV CMV VZV HHV-6
presentation of primary viral pneumonia
cough
breathlessness
cyanosis
causes of secondary bacterial pneumonia
s. pneumoniae
h. influenzae
s. aureus
colonising organisms in CF
s. aureus
p. aeruginosa
burkholderia cepacia complex
non-tuberculous mycobacteria and fungi
prevention of LRTIs
pneumococcal vaccination
influenza vaccination - 2-17 year olds
over 65s
chronic disease, multiple co-morbidities
what is aspergillosis
infection caused by aspergillus
who does allergic bronchopulmonary aspergillosis present in
people with atopy, asthma and CF
how does ABPA present
worsening asthma and lung function
diagnostic features of ABPA
high total IgE, specific IgE to aspergillosis, positive IgG to aspergillus
treatment of ABPA
corticosteroids and antifungal therapy
what is an aspergilloma
mobile mass of aspergillus within a pre-existing cavity
- old cavities left by TB and sarcoidosis
symptoms of aspergilloma
cough haemoptysis weight loss wheeze clubbing
treatment of aspergilloma
surgical resection
antifungals
how is TB transmitted
infection acquired by inhalation of respiratory droplets
bacilli lodge in alveoli and muliply
formation of Ghon focus
90% primary infection asymptomatic
presentation of TB
chronic productive cough haemoptysis weight loss fever night sweats can disseminate and affect other organisms
detection of TB
detection of acid fast bacilli
culture of m. tuberculosis
interferon gamma release assays +/- tuberculin skin test
treatment of TB
combined chemotherapy for several months
