Infectious Disease 1 Flashcards
What is different between adult and paediatric infections?
Self-limiting infections right up until life-threatening infections all can present with fever and rash
What is SIRS?
Systemic inflammatory response syndrome
Characterised by fever/hypothermia, tachycardia, tachypnoea, leucocytosis or leucocytopaenia
What is the paediatric definition of severe sepsis?
SEPSIS + multiorgan failure 2+ of: Respiratory failure Renal failure Neurologic failure Haematological failure Liver failure
What is ARDS?
Acute respiratory distress syndrome
Inflammatory response of the lungs
What bacteria are responsible for neonatal sepsis?
Group B strep
Escheria coli
Listeria monocytogenes
What bacteria are responsible for sepsis in children?
Strep pneumoniae
Meningococci
Group A strep
Staph aureus
What are the paediatric symptoms of sepsis?
Fever/hypothermia Cold hands/feet, mottled Prolonged cap refill time Chills/rigors Limb pain Vomiting +/- diarrhoea Muscle weakness Muscle/joint aches Skin rash Diminished UO
What pathogens are responsible for neonatal meningitis?
Group B strep
E. coli
Listeria monocytogenes
What pathogens are responsible for meningitis in children?
Strep pneumoniae
Meningococci
H. influenza
What are the signs/symptoms on meningitis in children?
Nuchal rigidity Headaches, photophobia Diminished consciousness Focal neurological abnormalities Seizures
Neonates: lethargy, irritability, bulging fontanelle (pressure around brain) nappy pain (pain from stretching the meninges when lifting the legs up)
Non-blanching rash typical of Neisseria
How does toxic shock syndrome differ from other types of shock?
Warm shock
Hands/feet warm and will not see mottled skin n
Feel warm because staph/strep toxins lead to ongoing dilatation
What is the traffic light scheme for diagnosing sepsis/meningitis in kids?
Looks at activity of the child, colour of skin, response to stimulation to environment, respiratory, circulation, hydration etc.
How do you Rx sepsis +/- meningitis?
Supportive Rx: ABC (inotropes/fluid)
DEF (don’t ever forget glucose)
Antibiotics with good penetration in CSF & broad spectrum (e.g. 3rd generation cefalosporins & amoxicillin if neonate)
Chemoprophylaxis of close household contacts (for Men B and Strep A)
What investigations should you do in suspected meningitis/sepsis?
FBC (leucocytosis, thrombocytopaenia)
CRP (elevated)
Coagulation factors (low due to DIC)
Blood gases (metabolic acidosis)
Glucose (hypoglycaemia)
CSF: pleocytosis, increase protein level, low glucose
Blood and CSF cultures (antigen testing, CSF)
Urine culture, skin biopsy culture
Imaging: CT-cerebrum (make sure safe to take LP)
When would you be able to do a skin biopsy to help diagnose meningitis?
If there is rash you may find the bacteria in the skin
What kind of bacteria is streptococcus pneumoniae?
Gram positive duplo-cocci
It colonises upper airways
Spread by droplets
What is the major predisposing factor for invasive disease with strep pneumoniae?
Viral infection
What kind of infection can pneumococcal disease lead to?
It has nasopharyngeal carriage and can spread locally to the sinuses/ear or can spread to lungs –> pneumonia/empyema
Can get into blood and cause septicaemia or meninges and cause meningitis
Many other places too
What kind of pneumonia is very characteristic of pneumococcal disease?
Lobar pneumonia
How can pneumococcal disease be prevented?
Pneumococcal vaccine - 13-valent
If pneumococcal meningitis isn’t treat quickly enough what complications can result?
Brain damage
Hearing loss
Hydrocephalus
What kind of bacteria is Hib?
Gram -ve
Encapsulated H. influenzae can resist phagocytosis and complete mediated lysis
Unencapsulated Hi is non-typeable
What can Hib cause?
Bacteraemia, meningitis, pneumonia, epiglottitis
What is the major factor predisposing to Hib infection?
Viral infection
How does meningococcus cause disease?
Meningococcus is carried in nasopharynx
Passage through epithelia
Meningococcus can enter BS
How long after meningococcus has entered the blood do we get symptoms?
<12h signs of septic shock
<18-36h signs of meningitis
What are some of the long term morbidities that survivors of meningococcal meningitis suffer?
Amputation, skin scarring, cognitive impairment/epilepsy/hearing loss
Who does meningococcal disease tend to affect?
Young children <1
What is the thing that makes meningococcal disease so virulent?
Endotoxin (lipopolysaccharide)
Endotoxin levels assoc. with higher mortality as it stimulates a septic cascade
