respiratory 2 Flashcards
what are the different classifications of pneumonia?
If the pneumonia developed outside of hospital it is labeled labelled “community acquired pneumonia”. If it develops more than 48h after hospital admission it is labelled “hospital acquired pneumonia”. If it develops as a result of aspiration, meaning after inhaling foreign material such as food, then it is labelled “aspiration pneumonia”
how does pneumonia present?
presentation: Shortness of breath Cough productive of sputum Fever Haemoptysis (coughing up blood) Pleuritic chest pain (sharp chest pain worse on inspiration) Delirium (acute confusion associated with infection) Sepsis
Signs - deranged basic observations - they may indicate sepsis secondary to pneumonia
Tachypnoea, Tachycardia, Hypoxia, Hypotension, Fever, Confusion
what are the three characteristic chest signs of pneumonia?
- Bronchial breath sounds. These are harsh breath sounds equally loud on inspiration and expiration. These are caused by consolidation of the lung tissue around the airway.
- Focal coarse crackles. These are air passing through sputum in the airways similar to using a straw to blow in to a drink.
- Dullness to percussion due to lung tissue collapse and/or consolidation.
how is the severity of pneumonia assessed?
NICE recommend using the scoring system CRB-65 out of hospital and CURB-65 in hospital. The only difference is that out of hospital you do not count urea.
When you see someone out of hospital with a CRB-65 score of anything other than 0 NICE suggest considering referring to the hospital.
C – Confusion (new disorientation in person, place or time)
U – Urea > 7
R – Respiratory rate ≥ 30
B – Blood pressure < 90 systolic or ≤ 60 diastolic.
65 – Age ≥ 65
The CURB 65 score predicts mortality (score 1 = under 5%, score 3 = 15%, score 4/5 = over 25%). The scoring system is there to help guide whether to admit the patient to hospital:
Score 0/1: Consider treatment at home
Score ≥ 2: Consider hospital admission
Score ≥ 3: Consider intensive care assessment
what are the common causes of CAP?
streptococcus pneumoniae - aka pneumococcus
also haemophilus influenza
what are the common causes of HAP?
gram negative bacilli, staph aureus
what is the most common cause of pneumonia in those with COPD?
H.influenzae
who is moraxella catarrhalis pneumonia common in?
Moraxella catarrhalis in immunocompromised patients or those with chronic pulmonary disease
what is a common cause of pneumonia in those with cystic fibrosis?
pseudomonas aeruginosa
staph aureus
what is atypical pneumonia ?
The definition of atypical pneumonia is pneumonia caused by an organism that cannot be cultured in the normal way or detected using a gram stain. They don’t respond to penicillins and can be treated with macrolides (e.g. clarithomycin), fluoroquinolones (e.g. levofloxacin) or tetracyclines (e.g. doxycycline).
what are the different types of atypical pneumonia?
- Legionella pneumophila
- mycoplasma pneumoniae
- chlamydophila pneumoniae
- coxiella brunettii - aka Q fever
- chlamidya psittaci
how does legionella pneumonia present?
Legionella pneumophila (Legionnaires’ disease). This is typically caused by infected water supplies or air conditioning units. It can cause hyponatraemia (low sodium) by causing an SIADH. The typical exam patient has recently had a cheap hotel holiday and presents with hyponatraemia.
how does mycoplasma pneumoniae present?
This causes a milder pneumonia and can cause a rash called erythema multiforme characterised by varying sized “target lesions” formed by pink rings with pale centres. It can also cause neurological symptoms in young patient in the exams.
how does chlamydophila pneumoniae present?
Chlamydophila pneumoniae. The presentation might be a school aged child with a mild to moderate chronic pneumonia and wheeze. Be cautious though as this presentation is very common without chlamydophilia pneumoniae infection.
how does coxiella burnetii present?
Coxiella burnetii AKA “Q fever”. This is linked to exposure to animals and their bodily fluids. The MCQ patient is a farmer with a flu like illness.
how does chlamydia psittaci present?
Chlamydia psittaci. This is typically contracted from contact with infected birds. The MCQ patient is a from parrot owner.
what is a common cause of fungal pneumonia?
Pneumocystis jiroveci (PCP) pneumonia occurs in patients that are immunocompromised. It is particularly important in patients with poorly controlled or new HIV with a low CD4 count. It usually presents subtly with a dry cough without sputum, shortness of breath on exertion and night sweats. Treatment is with co-trimoxazole (trimethoprim/sulfamethoxazole) known by the brand name “Septrin”. Patients with low CD4 counts are prescribed prophylactic oral co-trimoxazole to protect against PCP.
what is a common cause of pneumonia in alcoholics?
klebsiella pneumoniae
this is also seen often in diabetics
and commonly causes lung abscess formation and empyema
what investigations would you perform for pneumonia?
CXR - will show a new shadowing (consolidation)
FBC - raised WCC
U&E’s - for urea - assess for severity of disease
CRP - for inflammation and infection
ABG
in patients with moderate/severe:
sputum cultures
blood cultures
legionella and pneumococcal urinary antigens
how is CAP managed?
low severity
1st line - amoxicillin (if allergic to penicillin use either a macrolide (clarithromycin) or tetracycline (doxycycline) - give Abx for 5 days
high severity
dual antibiotic therapy is recommended with amoxicillin and a macrolide
what are the complication of pneumonia?
sepsis pleural effusion empyema lung abscess death
how is HAP managed?
within 5 days of admission: co-amoxiclav or cefuroxime
more than 5 days after admission: piperacillin with tazobactam or a broad spectrum caphalosporin e,g, ceftazidime or a quinolone e.g. ciprofloxacin
where is the most common place of lung cancer?
95% are carcinoma of the bronchus
2% are alveolar tumours
what can cause secondary lung cancer?
breast kidney uterus ovary testes thyroid
what are some causes of lung cancers?
smoking - causes 90% urban living opposed to rural passive smoking asbestos (will cause mesothelioma) arsenic iron oxide chromium petroleum products oil radiation scarring e.g. post TB
*tumours associated with occupational factors tend to be adenocarcinomas
what are the different types of lung cancer?
small cell lung cancer - around 15-20% of cases - generally carry a worse prognosis. Usually found around the hilum/central. SCLC cells contain neurosecretory granules that can release neuroendocrine hormones. This makes SCLC responsible for multiple paraneoplastic syndromes.
non small cell lung cancer
- squamous cell carcinoma - 35%
- adenocarcinoma - 25%
- large cell - 10-15%
- alveolar cell carcinoma - not smoking related, lots of sputum
- bronchial adenoma - mostly carcinoid
how does a squamous cell carcinoma of the lung usually present?
- usually presents as obstructive lesions of the bronchus leading to infection
- occasionally they will cavitate - this will occur when the central part of the tumour undergoes necrosis - on x-ray this may look like and abscess, or a TB cavity, but on a CT, you will clearly be able to see the jaggered edge of the cavity.
- local spread is common, but mets are normally late - but frequent
- often will cause hypercalcaemia - by bone destruction or production of PTH analogues
- there may be hyperthyroidism due to ectopic TSH
what are the features of a lung adenocarcinoma?
Arises from mucous cells in the bronchial epithelium
Commonly invades the mediastinal lymph nodes and the pleura, and spreads to the brain and bones
Does not usually cavitate
Can cause excessive mucous secretion
Proportionally more common in non-smokers, women and in the Far East
i.e. these are the least likely to be related to smoking
May sometimes be confused with mesothelioma
Most likely to cause pleural effusion (as are mesotheliomas)
there may be gynaecomastia
there may be hypertrophic pulmonary osteoarthropathy
what are the features of large cell carcinomas?
These are basically just less well differentiated versions of adenocarcinomas and squamous cell carcinoma – i.e. squamous cell and adenocarcinomas have a longer time to develop before presentation, they will present as large cell carcinomas.
They metastasise early
Associated with poor prognosis
they may secrete B-HCG
what are the features of bronchoalveolar carcinoma?
These are very rare
It is a variation of adenocarcinoma
they account for 1-2% of all lung carcinoma
they will present as a single nodule, or many small nodular lesions
occasionally they cause production of huge amounts of mucous (which will be coughed up as sputum)
may appear like consolidation on the CXR
Causes ‘bronchorrhoea’ – diarrhoea of the bronchus – produces huge amounts of white sputum!
what are the features of a small cell lung cancer?
they arise from endocrine cells - kulchitsky cells - these are ADPU cells and as a result these tumours will secrete many poly-peptides.
some of these poly-peptides will cause auto-feedack and induce further cell growth.
they are associated with ectopic ADH and ACTH secretion
so they can presentations such as addisons and cushings (ACTH - won’t be typical cushing, hypertensions, hyperglycaemia, hypokalaemia, alkalosis and muscle weakness are more common than a buffalo hump) and hyponatraemia (ADH), lambert-eaton syndrome
almost always inoperable at presentation - they do respond to chemo but prognosis is generally poor.
what are ADPU cells?
Amine - high amine content
Precursor Uptake - high uptake of amine precursors
Decarboxylase - high content of the enzyme decarboxylase
APUD cells – there are two types:
Open – secrete products in response to luminal contents, as well as nervous and hormonal stimuli
Closed – have no luminal receptors, and just respond to nervous and hormonal stimuli.
