Paediatric Infectious Diseases Flashcards
what are the most common cause of bacterial meningitis in children and adults? and neonates?
- Nisseria meningitidis
- Streptococcus pneumoniae
- group B strep in neonates, also E.coli and listeria
What are the typical symptoms of meningitis in adults and children?
- fever
- neck stiffness
- vomiting
- headache
- photophobia
- altered consciousness
- seizures
- non-blanching rash if there is meningococcal septicaemia.
what non-specific signs and symptoms can present in neonates and babies with meningitis?
- hypotonia (floppy)
- poor feeding
- lethargy
- hypothermia
- bulging fontanelle
when would a lumbar puncture be part of the investigation for a neonate/baby?
- under 1 month presenting with fever
- 1-3 months with fever and are unwell
- under 1 year with unexplained fever and other features of serious illness
what is the management for bacterial meningitis?
Primary care:
- urgent stat injection (IM or IV) of benzylpenicillin prior to transfer to hospital, as time is so important.
Hospital:
- lumbar puncture
- blood tests for meningococcal PCR if suspected
- antibiotics:
under 3 months: cefotaxime plus amoxicillin
above 3 months: ceftriaxone
- vancomycin can be added if risk of peniccilin resistance
- steroids: dexamethasone 4x a day for 4 days to children over 3 months
meningitis complications
- hearing loss
- seizures and epilepsy
- cognitive impairment and learning disability
- memory loss
- cerebral palsy
what is sepsis?
- Systemic inflammatory response syndrome (SIRS) + suspected or proven infection
- Severe sepsis = sepsis + organ dysfunction
- Septic shock = sepsis + CVS dysfunction
what is the criteria for systemic inflammatory response syndrome (SIRS)?
2 or more of:
- temperature > 38 or < 36
- WCC > 15 x 10^9/L or < 5 x 10^9/L
- tachycardia > 2SD above normal for age
- tachypnoea > 2SD above normal for age
signs of sepsis in neonates/babies
- deranged physical obs
- prolonged capillary refill time
- fever or hypothermia
- deranged behaviour
- poor feeding
- inconsolable or high-pitched crying or weak crying
- reduced consciousness
- floppy
- skin colour changes (cyanosis, mottled pale or ashen)
what is the immediate management of sepsis?
- oxygen if evidence of shock or sats < 94%
- obtain IV access
- blood tests: FBC, U&E, CRP, clotting screen, blood gas for lactate and acidosis.
- blood cultures, ideally before antibiotics
- urine dipstick
- antibiotics within 1 hour of presentation: Cefotaxime/ceftriaxone + IV amoxicillin if < 1 month old
- IV fluids: 20ml/kg IV bolus of saline if lactate > 2mmol/L or there is shock.
- 2ml/kg 10% dextrose
what are some further investigations/management after immediate treatment of sepsis?
- CXR is pneumonia suspected
- abdo pelvic US if intra-abdo infection suspected
- lumbar puncture if meningitis suspected
- meningococcal PCR if meningococcal disease suspected
- serum cortisol if adrenal crisis suspected
Continue antibiotics for 5 – 7 days if a bacterial infection is suspected or confirmed. Bacterial culture and sensitivities can be very helpful in guiding antibiotics.
Consider stopping antibiotics where there is a low suspicion of bacterial infection, the patient is well and blood cultures and two CRP results are negative at 48 hours.
What clinical tests can indicate meningitis?
- nuchal rigidity (neck stiffness)
- Brudzinski’s sign: hips and knees flex on passive flexion of the neck
- Kernig’s sign: pain on passive extension of the knee
what are the causes of childhood meningitis?
Bacterial (4-18%)
Viral – Mainly Enterovirus (54-88%)
Fungal – Neonates/Immunocompromised
Unknown/aseptic (40-76%)
describe Neisseria meningitidis
- Gram negative diplococcus
- Humans only natural hosts
- Nasopharyngeal carriage
- Transmission via respiratory secretions
- Infection often follows viral URTI
- Polysaccharide capsule:
capsule composition determines serogroup (eg. A, B, C, W, Y) - Endotoxin (LPS)
invasive meningococcal disease risk factors
- age < 1 year or 15-24 years
- unimmunised
- crowded living conditions
- household or kissing contact
- cigarette smoking (active or passive)
- recent viral/Mycoplasma infection
- complement deficiency
what are the risk factors for invasive pneumococcal disease (e.g. streptococcus pneumonia)?
- age < 2 years
- cigarette smoking (active or passive)
- recent viral URTI
- attendance at childcare
- cochlear implant
- sickle cell disease
- asplenia
- HIV infection
- nephrotic syndrome
- immunodeficiency/immunosuppression
what would be the lumbar puncture finding in bacterial meningitis?
- appears turbid or purulent
- high opening pressure
- ^^^ WCC (neutrophils)
- ^^^ protein
- decreased glucose (< 50% serum)
The majority of skin and soft tissue infections are caused by?
- staph infection (s.aureus)
- strep infections (s.pyogenes)
Staphylococcal scalded skin syndrome clinical presentation
- usually < 5 years old
- toxin mediated (exfoliatoxin)
- initial bullous lesions followed by widespread desquamation
- mild fever
- purulent conjunctivitis
- Nikolsky sign
staphylococcal scalded skin syndrome treatment
- IV flucloxacillin + IV fluids
Scarlett fever clinical presentations
- 2-5 day incubation period
- fever, malaise, sore throat
- strawberry tongue
- sandpaper rash
- skin peeling (desquamation)
- exclusively caused by streptococcus pyogenes
Scarlet fever management
- notifiable disease > inform public health
- Phenoxymethylpenicillin (Penicillin V) for 10 days
Scarlet fever complications
- abscess formation (retropharyngeal or peritonsillar (quincy))
- acute rheumatic fever
- post-streptococcal glomerulonephritis
what causes toxic shock syndrome (TSS)?
- acute febrile illness caused by gram +ve bacteria (S.aureus & GAS) rapidly progressing to shock and multi-organ failure.
- superantigen causes intense T-cell stimulation > excessive immune activation > pro-inflammatory cytokine release
toxic shock syndrome (TSS) clinical features
- fever
- diffuse, maculopapular, ‘sunburn’ rash
- mucosal changes: non-purulent conjunctivitis, swollen lips, strawberry tongue
- profuse diarrhoea (S.aureus)
- rapid progression to shock and multi-organ failure
TSS management
- ABC
- Fluid resuscitation +/- inotropes
- cultures: blood, throat swabs, wounds
- IV Abx: flucloxacillin + clindamycin
- IVIG
- avoid NSAIDs
- surgical debridement
