Infections and Immunity Flashcards
What immunisations are given <1yr? (8)
8 weeks (2 months):
1) 6-in-1 vaccine
2) Pneumococcal (PCV) vaccine
3) Rotavirus vaccine
4) MenB
12 weeks (3 months):
5) 6-in-1 vaccine - 2nd dose
6) Rotavirus vaccine - 2nd dose
16 weeks (4 months):
7) 6-in-1 vaccine - 3rd dose
8) PCV - 2nd dose
9) MenB - 2nd dose
What immunisations are given aged 1-15yr? (10)
1 year:
1) Hib/MenC - 1st dose
2) MMR - 1st dose
3) PCV - 3rd dose
4) MenB - 3rd dose
2-10yrs:
5) Flu vaccine - every year
3yrs and 4 months:
6) MMR - 2nd dose
7) 4-in-1 pre-school booster
12-13yr:
8) HPV vaccine
14yr:
9) 3-in-1 teenage booster
10) MenACWY
What immunisations are given to adults? (3)
65yr:
1) Pneumococcal (PPV) vaccine
2) Flu vaccine (and every year after)
70yr:
3) Shingles vaccine
What immunisations are offered to pregnant women? (2)
Flu vaccine - during flu season Whooping cough (pertussis) vaccine - from 16 wks
What is in the 6-in-1 vaccine?
DHHPTW
1) Diptheria
2) Hep B
3) Hib - Haemophilus influenza type b
4) Polio
5) Tetanus
6) Whooping cough - pertussis
What is in the 4-in-1 pre-school booster?
DTPP
1) Diphtheria
2) Tetanus
3) Whooping cough - pertussis
4) Polio
What is in the 3-in-1 teenage booster?
DTP
1) Diphtheria
2) Tetanus
3) Polio
Which vaccines are live? (3)
1) Influenza
2) MMR
3) Rotavirus (oral)
+ BCG
When does meningitis mostly occur in children?
Mostly in first 5 years of life
75% of cases are <15yrs
Younger children are at greater risk of brain damage and are more difficult to diagnose
How does bacterial infection of the meninges occur, and why is this more likely to occur in children?
Colonisation of nasopharyngeal epithelium
Invasion of blood then meninges - BBB is less developed in children so these bugs are more likely to reach the meninges and cause infection
Cerebral oedema caused by inflammation + leaky vessels
What is the pathophysiology of viral meningitis?
Infection of a mucus membrane followed by lymph node involvement
Primary viraemia = causes viral illness
Secondary viraemia = involved organs such as liver
What are some risk factors for neonatal meningitis? (6)
1) Low birth weight (<2500g)
2) Prematurity
3) Premature rupture of membranes
4) Traumatic delivery
5) Fetal hypoxia
6) Maternal peripartum infection
What are the most common bacterial causative organisms of meningitis in neonates? (3)
1) Group B strep
2) E coli
3) Listeria monocytogenes
+ other coliforms
What are the most common bacterial causative organisms of meningitis in infants (1 month to 2 years) (4)
Streptococcus pneumoniae
Neisseria meningitides
Haemophilus Influenza B
Meningococcus C
**The last 2 are both now vaccinated against and so their incidence has dropped
What are the most common causative organisms of meningitis in adolescents / adults? (3)
1) Neisseria meningitidis
2) Streptococcus pneumoniae
3) Listeria monocytogenes
What symptoms may meningitis present with? (13)
Photophobia, neck stiffness and headache are the classical distinguishing symptoms but the young child (infant) might not have these making diagnosis more difficult
Infants may have non-specific signs of infection
- High-pitched cry
- Bulging fontanelle
- Poor feeding
- Respiratory distress
Other meningitic signs
- Irritable
- Vomitting
- Drowsiness
- Seizures
What are some signs of raised ICP? (6)
1) Papilloedema
2) Altered / LOC
3) Bulging fontanelle in neonates
4) Increased BP
5) Decreased HR
6) Irregular respirations
7) Focal neurological signs
What is meningitis vs meningococcal septicaemia?
Meningitis = inflammation of the leptomeninges that surround the brain and spinal cord
- Various causative organisms
- May have neck stiffness / photophobia
- Unlikely to have a rash
Meningococcal septicaemia = systemic infection
- CAUSED BY NEISSERIA MENINGITIDIS
- Rapidly spreading purpuric rash
- May or may not also have meningitis
- Often fatal
What signs of meningism can be found on examination
1) Kernig’s sign - unable to extend knee when thigh flexed to 90 degrees
2) Brudunski’s sign - involuntary lifting of leg when lying supine and head is raised
What investigations are done in meningitis? (6)
Do not delay abx by more than 30 mins
1) Bloods - FBC, U&Es, CRP, glucose, blood cultures, gases
2) CT head
3) LP unless contraindicated
4) Urine for MC+S
5) Nasal / throat swabs
6) CXR - lung abscess
What would the LP results be in bacterial vs viral meningitis?
Viral:
- Clear / hazy appearance
- Lymphocytes +
- Protein +
- Glucose = Normal
Bacterial:
- Cloudy / purprulent
- Neutrophils ++
- Protein ++
- Glucose = Low
List some contraindications to LP (7)
1) Raised ICP = stabilise first
2) Shock = stabilise first
3) After convulsions = stabilise first
4) Respiratory insufficiency = stabilise frist
5) Abnormal clotting
6) Infection at LP site
7) Extensive purpura
What is a pyrexia?
What is a red flag?
What is an amber flag?
Temp of 38 degrees celsius or more
Infants <3 months, fever of more than 38 = red flag
Infants 3-6 months, fever of over 39 = amber flag
What is the treatment of suspected meningococcal meningitis in the community?
If in doubt - treat as bacterial
IM benzylpenicillin single dose
<10yr = 1g 1-9yr = 600mg <1yr = 300mg
What is the treatment of suspected bacterial meningitis in hospital?
<3 months = IV cefotaxime + amoxicillin/ampicillin to cover listeria
> 3 months = IV ceftriaxone
+ dexamethasone to reduce neurological sequelae
Symptomatic treatment - antipyretics, analgesics, IV fluids
Inform PHE - they offer ciprofloxacin to all close contacts
Which bacterium and which virus cause the highest morbidity/mortality in meningitis?
Streptococcus pneumoniae
HSV
What are some complications of meningitis?
Immediate:
- Septic shock
- Seizures
- DIC
- Cerebral oedema
- Hydrocephalus (blockage of ventricular outlet)
Delayed:
- Hearing loss (follow up includes hearing test)
- Epilepsy
- Cerebral palsy (if <2yr)
What vaccinations are given as prevention for meningitis and when are they given?
Men B vaccine is given at 2, 4 and 12-13 months
Meningitis ACWY given at 13-18 years old