Week Two - Case Two Flashcards
what is pneumonia and what is it characterised by
a common lower respiratory tract infection and is characterised by inflammation of the lung tissue.
it is almost always an acute infection, and almost always is caused by bacteria.
what is diagnosis of pneumonia usually confirmed by
chest x-ray
what is the most fatal hospital acquired infection
pneumonia
what percentage of pneumonia cases at pneumococcal in cause and what are the rest
75% of cases are pneumococcal in cause, and 20% atypical. The remaining 5% may be caused by aspiration of vomit, radiotherapy and allergic mechanisms.
what is hospital acquired pneumonia defined as
pneumonia that develops 48hrs after admission
what is the prognosis for hospital acquired pneumonia
generally poor, due to co-morbidities, older age range of patients, and resistance of organisms
what are the common organisms in hospital acquired pneumonia
gram negative bacilli, staphylococcus aureus
drug resistant organisms are more common and are more dangerous
what is the prognosis for community acquired pneumonia
generally good, especially for younger patients
S. pneumoniae and viral pneumonias are still fatal in older patients
what are the common organisms in community acquired pneumonia
streptococcus pneumoniae, haemophilius influenzae
anaerobes are rare
what does step pneumoniae infection often follow
often follows viral infection with influenza or parainfluenza
what is hospital acquired infection often with
gram negative organisms
what are the symptoms of pneumonia
Typically the same for hospital acquired / non-hopsital acquired cases
Shortness of breath
Cough
May be productive in adolescents and adults – Purulent sputum possible
Often dry in infants and the elderly
Fever
Rigors
Vomiting
Headache
Loss of appetite
Very occasionally – haemoptysis
Pleuritic chest pain – which may on occasion radiate to the shoulder (if diaphragm is involved) or the anterior abdominal wall
Pleuritic chest pain – a sharp shooting or stabbing pain, usually in the side, that is most painful on inspiration, but can also be felt on expiration, or even whilst talking.
Upper abdominal tenderness in some patients with lower lobe pneumonia
Signs of consolidation – both on examination and CXR
Dyspnoea
Tachypnoea
Tachycardia
Increased secretions – noticeable in ventilated patient in hospital acquired cases
what are the signs seen in strep pneumoniae
rapid shallow breathing and pleural rub
what may be the only sign in elderly patients
confusion
what oxygen saturation is usually worrying
<92%
what would a CXR look like
- evidence of infiltrate in the form of consolidation
- changes may not appear for up to 48hrs after symptoms, however, after effective treatment, consolidation may still be seen on CXR for up to 6 weeks
what is not routine in community acquired infection of pneumonia
blood cultures to assess the identity of the causatory organism
what would a FBC show
- elevated WCC
- elevated ESR (>100mm/h) and increased CRP
- possible anaemia (sign of abscess)
- blood cultures - check for septicaemia
why would one take a urine sample in suspected pneumonia
in severe cases of pneumonia, where legionella is suspected, urine testing for legionella antigen may be indicated
what is pleural fluid aspiration test used for
to assess for organisms.
what is the CURB-65 score and what is it used for
used to assess the severity of community acquired pneumonia. it predicts the risk of mortality. (CURB score 0 = <1% risk, CURB score 5= 60% risk). Each factor of the score is worth 1 point
C – Confusion – use the abbreviated mental test (score ≤8)
U – Urea – >7mmol/L
Respiratory rate – ≥30/min
Blood Pressure <90 systolic, or <60 diastolic
65 – age >65 years
A score ≥3 is severe pneumonia. ≥2 requires hospitalisation
what are the differentials for pneumonia
PE - patient is not usually scenically unwell. shortness of breath is more likely to be of a sudden onset
pulmonary/pleural TB
pulmonary oedema
what is the treatment for pneumonia if not vomiting and CURB65 score is < or equal to 2
use oral antibiotics, if severe and/or vomiting IV antibiotics are required
what should oxygen saturation be kept at
> 92%
what is used to prevent dehydration and shock
fluids
what is the most common complication of pneumonia
respiratory failure
what is respiratory failure defined as
PaO2 <8kPa.
what is respiratory failure treated with
60% oxygen (high flow)
what should you aim to keep stats at when on oxygen
90-94%
what may be given if atrial fibrillation occurs
this is the most common complication in the elderly. it usually resolves but digoxin may be given to reduce the HR as short term therapy
what is empyema
the infection of the pleural fluid
what is lobar collapse most commonly the result of
sputum retention
what is a late complication of pneumonia
lung abscess - this is a cavitating lesion containing pus within the lung
what can septicaemia result in
infective endocarditis and meningitis
what is the most common type of pneumonia
strep-pneumonia
very commonly preceded by viral infection
what happens in cases of strep pneumoniae
the patient will rapidly become febrile, with a temp of up to 39.5, pleuritic pain and dry cough
may be pleural rub and rust coloured sputum
what strains are common in the young, but rare in the elderly
Mycoplasma pneumoniae, Chlamydia pneumoniae
what stains are common in the elderly but not in young people
Haemophilus influenzae
if someone smoked 5 cigarettes per day for 60 years what is their smoking history in pack years
5 cigarettes per day = 1/4 pack
60 x 1/4 = 15 pack years
what is myalgia
muscle aches and pain
what is anosmia
partial or full loss of smell
what does a CURB65 score of greater than 3 mean
urgent admission to hospital
what initial investigations should u order when querying pneumonia
- ABG
- blood cultures
- CRP
- CXR
- ECG
- FBC
- Lactate
- LFTs
- U+E
what is the initial management of a patient with potential pneumonia
- start oxygen
- monitor urine output
- start antibiotics
- start IV fluids
what is an elevated lactate level indicative of
sepsis
what samples would you send to the microbiology labs if querying CAP
- sputum cultures
- blood cultures
- HIV test
- respiratory virus screen
- urine pneumococcal and legionella antigen
what are the common clinical presentations of someone with pneumonia
cough: may be dry or productive. Sputum in pneumococcal pneumonia is characteristically rust coloured.
breathlessness: alveoli become filled with pus which impairs gas exchange, the patient will complain of feeling breathless, not able to lie down and reduction in oxygen saturations
fever: this can be up to 39.5 to 40 degrees
chest pains: commonly pleuritic in nature and worse when coughing
what is a sign of effusion
Dullness on percussion
what in particular do we want to look at in the FBC
white cell count
haemoglobin
platelets
what is bacterial pneumonia characterised by
acute inflammation of the lung parenchyma
this is associated with neutrophil inflitration
what test should patients presenting with pneumonia be offered
a HIV test
what kind of bacteria is streptococcus pneumoniae
gram positive coccus
what is the key information of streptococcus pneumoniae
Commonest cause of CAP, up to 80% of infections.
Can be detected from blood culture (in 30% of cases) or via urinary antigen.
Vaccine available for babies and >65 year olds, for immunosuppressed and asplenic patients and those with long term conditions.
Rates of infection have fallen due to immunisation.
what type of bacteria is haemophilus influenzae
gram negative bacillus
what is the key information about haemophilus influenzae
Rates of infection have fallen as children now immunised.
Note: vaccine does not cover for all serotypes and is not particularly efficient in adults
Around 20% of UK strains now resistant to penicillins.
what type of bacteria is Klebsiella pneumoniae
gram negative bacteria
what is the key information about Klebsiella pneumoniae
Commensal organism of the GI tract.
Elderly patients and people with comorbidities at increased risk, alcohol excess also risk factor
Clinically tends to affect upper lobes
Inherently resistant to penicillins, cephalosporins recommended, penicillin combined with a beta-lactamase inhibitor may be an option.
what type of bacteria is staphylococcus aureus
gram positive coccus
what is the key information about staphylococcus aureus
Chronic lung pathology also a risk factor, i.e., cystic fibrosis and bronchiectasis
Flucloxacillin mainstay of therapy but important to consider MRSA if not improving
what are the atypical causes of pneumonia
mycoplasma pneumoniae
legionella pneumonophilia
chlamydia pneumoniae
Chlamydia psittaci
what is the key information about mycoplasma pneumoniae
Can be associated with epidemics and tends to affect younger patients.
Dry cough Patchy consolidation on CXR
Cannot be cultured in routine laboratories, diagnosis by PCR or serology
Treat with macrolide
what is the key information about legionella pneumophilia
Occasionally sporadic cases but often occur in outbreaks, associated with air conditioning systems.
Think of this in patients who have recently been on holiday.
Tends to affect males (2:1 ratio) and smokers.
Prodromal syndrome of high fevers before a dry cough develops
Can be diagnosed with urinary antigen testing.
Treat with macrolides.
5-10% of CAP.
Occurs in outbreaks in families and institutions
what is the key information about chlamydia pneumoniae
Young adults and extremes of age vulnerable
Diagnosis made on acute and convalescent serology or PCR Treat with macrolide or doxycycline.
Around 3% of CAP
what is the key information about Chlamydia psittaci
Classically associated with contact with birds esp. parrots and pigeons
Can occasionally cause hepatosplenomegaly
Diagnosis made on acute and convalescent serology or PCR Treat with macrolide or doxycycline.
what is meant by typical and atypical pneumonia
Pneumonia is classically divided into typical and atypical organisms based on historical laboratory techniques: typical organisms can be cultured in the laboratory whereas atypical organisms are intracellular pathogens and cannot be cultured using standard methods and alternative diagnostic tools are needed. This division is clinically relevant as atypical organisms need to be treated with antibiotics which get into intracellular space (e.g. macrolides). Also, atypical organisms do not possess a cell wall on which penicillins or cephalosporins can act.
what is common in pneumonia and complicates around 50% of cases
pleural effusion
what is empyema
collection of pus in the pleural space
what antibiotics should be started for case patients pneumonia
Co-amoxiclav 500/125mg tds clarithromycin 500mg bd for 5/7
As per CURB65 guidelines, this prescription offers broad spectrum cover of potential microbial causes of pneumonia.
why do we prescribe clarithromycin
In severe pneumonia, we add additional antibiotic treatment (typically with clarithromycin) to broaden antibiotic spectrum and cover atypical bacterial causes of pneumonia.
what should happen to all pneumonia patients after 6 weeks
have a follow up CXR in 6 weeks because
chest radiograph should be arranged after about 6 weeks for patients who have persistence of symptoms or physical signs or who are at higher risk of underlying malignancy (especially smokers and those aged >50 years. The vast majority of patients (98%) who are diagnosed with CAP have a significant risk factor for underlying malignancy. Follow-up CXR screens for malignancy after the acute infiltrate has cleared.
