Infectious Diseases - Common Infections Flashcards
Presentation of chest infections.
- cough
- sputum production
- shortness of breath
- fever
- lethargy
- crackles on chest
Typical causes of chest infections.
Streptococcus pneumonia (50%)
Haemophilus influenzae (20%)
Which bacterial colonisation is typical of a patient with pneumonia, who is immunocompromised?
Moraxella catarrhalis
Which bacterial colonisation is typical of a patient with pneumonia, who has COPD?
Pseudomonas aeruginosa
Which bacterial colonisation is typical of a patient with pneumonia, who has cystic fibrosis?
Pseudomonas aeruginosa or Staphylococcus aureus
Which bacterial colonisation is typical of a patient with pneumonia, who has bronchiectasis?
Haemophilus influenzae
Pseudomonas aeruginosa
What are the atypical causes of pneumonia?
Legions of psittaci MCQs:
Legionella pneumophilia
Chlamydia psittaci
Mycoplasma pneumonia
Chalmydydophila pneumonia
Q fever
Which antibiotic choice would be appropriate to commence in the community for a patient with typical pneumonia?
Amoxicillin
Erythromycin or clarithromycin if penicillin allergic.
What is infective endocarditis?
Infection of the endothelium of the heart, most commonly affecting the heart valves.
Risk factors for infective endocarditis.
- IVDU
- structural heart pathology
- CKD
- immunocompromised (e.g. HIV, cancer)
- history of infective endocarditis
Give an example of some structural pathologies that can increase the risk of infective endocarditis.
- valvular heart disease
- congenital heart disease
- hypertrophic cardiomyopathy
- prosthetic heart valves
- implantable cardiac devices
What are the causes of infective endocarditis?
Staphylococcus aureus is most common.
Presentation of infective endocarditis.
- fever
- fatigue
- night sweats
- muscle aches
- anorexia
Any pyrexia of unknown origin should prompt infective endocarditis as a differential.
Examination findings of infective endocarditis.
- new or changing heart murmur
- splinter haemorrhages
- petichiae
- Janeway lesions
- Osler’s nodes
- Roth spots
- splenomegaly
- finger clubbing
How should infective endocarditis be investigated?
3x blood culture samples BEFORE staring abx, separated by at least 6 hours and taken from different sites.
Echocardiography is usual imaging investigation.
Which criteria is used to diagnose infective endocarditis?
Modified Duke Criteria (see image)
How is infective endocarditis managed?
IV broad spectrum antibiotics (e.g. amoxicillin and gentamicin).
Surgery may be required for heart failure, large abscesses or infections not responding to abx.
What are the complications of infective endocarditis?
- heart valve damage (regurgitation)
- heart failure
- infective emboli
- glomerulonephritis
What is meningitis?
Inflammation of the meninges, which are the lining to the brain and spinal cord.
What is Meningococcal septicaemia?
Neisseria meningitidis enters the bloodstream.
It is the cause of the classic non-blanching rash, which indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
What are the most common causes of bacterial meningitis in children and adults?
Neisseria meningitidis
Streptococcus pneumoniae
What is the most common cause of bacterial meningitis in neonates?
Group B streptococcus.
Vertical infection route, contracted during birth from GBS bacteria that can often live harmlessly in the mothers vagina.
Presentation of meningitis in children and adults.
Triad of meningism:
- headache
- neck stiffness
- photophobia
Plus:
- n+v
- fever
- non-blanching rash in meningococcal septicaemia
Presentation of meningitis in neonates.
Very non-specific signs and symptoms such as hypotonia, poor feeding, lethargy, hypothermia and a bulging fontanelle.
NICE recommend lumbar puncture as part of the investigation for all children who:
- Under 1 months presenting with fever
- 1-3 months with fever and are unwell
- Under 1 years with unexplained fever and other features of serious illness
Which tests can be performed to look for meningeal irritation?
- Kernig’s test
- Brudzinski’s test