Acutely Unwell Child

Question 1

What is Kawasaki diseaseand how does this present in children

Answer 1

consider this if there is fever that has lasted >5 days

Kawasaki disease causes the blood vessels to become inflamed and swollen, which can lead to complications in the blood vessels that supply blood to the heart

Children with Kawasaki disease might have high fever, swollen hands and feet with skin peeling, and red eyes and tongue.

Question 2

What are consequences of Meningitis

Answer 2

septicaemia
permanent damage to the brain or nerves

Question 3

What are Common bacteria that cause meningitis in children

Answer 3

Neisseria meningitis
Streptoccus Pnenumoniae- most common in adults
Haemophilus influenzae

group B streptococcus-most common in children

Question 4

Symptoms and signs of meningitis and meningococcal disease

Answer 4

Fever
vomiting/nausea
headache
non-blanching rash
altered mental state

Non-blanching rashes are rashes which do not disappear with pressure, particularly using the ‘glass test’

Question 5

What is Kerning´s sign and Brudzinki´s sign?

Answer 5

Kerning´s sign
if the patient flex leg at knee, lifts a leg at hip 90º, then straightens
if this causes intense back pain, it is called Kernig´s sign
Kernig begins at the Knee

Brudzinki’s sign
flexing their head causes them to flex their knees

Question 6

Is a CT scan needed for Meningitis

Answer 6

not necessary if the child does not show signs of ICP

Checks for ICP before doing Lumbar Puncture

Question 7

What do you do in Primary Care with suspected bacterial meningitis or suspected meningococcal septicaemia (with non blanching rash)

Answer 7

give IM/IV benzylpenicillin 500mg asap

urgent hospital transfer

Question 8

What do you do in Primary Care with Suspected bacterial meningitis without non-blanching rash

Answer 8

no need for parenteral antibiotics
call 999

Question 9

What are normal Lumber Puncture Findings

Answer 9

Clear appearance
Lymphocytes < 4
no polymorphs
glucose >2.2
protein <0.4

Question 10

What are Bacterial Lumber Puncture Findings

Answer 10

Turgid appearance
cells per mm2: 5-2000 (more cells than viral)
neutrophils> lymphocytes
glucose very low (due to consumption by bacteria)
protein >1 (high due to protein synthesis by WBCs eg TNF)
other tests: gram staining

Question 11

What are Viral Lumber Puncture Findings

Answer 11

Clear appearance
cells per mm2: 5-500
Lymphocytes, no neutrophils
glucose normal
protein 0.5-0.9
Other tests: PCR

Question 12

Name how bacteria can evade the immune response

Answer 12

bacteria can lack polysaccharide capsule, so evade opsonisation

IgA protease

Question 13

What is Reverse Vaccinology

Answer 13

Reverse vaccinology = making vaccine by starting with genome sequence of pathogen strain

1 - Genome sequence to find Open Reading Frames (gene that codes regions inducing Ab response)
2 - Synthesise recombinant proteins
3 - Inject proteins into mouse
4 - Take serum from injected mice
5 - ELISA and FACS of mouse serum to identify which ABs
6 - Whichever ORF proteins activated humoral Ab response -> include in vaccine

Question 14

How does S. pyogenes (Group A Streptococcus) strain H292 evade the immune system?

Answer 14

H292 produces a molecule that interferes with neutrophil recruitment.

Question 15

What enzyme do Invasive strains of Group A Streptococcus Meningitis produce?

Answer 15

SpyCEP

Question 16

What Enzyme is SpyCEP?

Answer 16

Il-8 (CXCL8) protease

Question 17

How do ScpA and SpyCEP ablate neutrophil recruitment in vivo?

Answer 17

SpyCEP selectively cleaves chemoattractant Il-8 impairing neutrophil recruitment

Question 18

What does cepA gene code for?

Answer 18

cepA gene encodes SpyCEP

Knockout of cepA results in impaired GAS survival and reduced spread to the regional lymph nodes.

Knock-in of cepA into L.lactis results in enhanced survival and rapid spread to organs.

Question 19

What is Kcat?

Answer 19

Kcatis the number of substrate molecules processed per second.

Question 20

What is the difference between Meningitis and Meningococcal disease?

Answer 20

Meningitis - inflammation of pia and arachnoid mater of brain and spinal cord
Meningococcal disease - any disease caused by Neisseria meningtidis

Question 21

What are the three presentations of meningococcal disease

Answer 21

Causes m. meningitis (form of bacterial meningitis) in 15% of cases- non-blanching rash

Causes m. septicaemia in 60% of cases

Causes symptoms of both in 15% of cases

Question 22

Is viral or bacterial meningitis more common?

Answer 22

Viral

Question 23

What symptoms are specific to Meningitis

Answer 23

• Neck stiffness
• Photophobia
• Non-blanching rash
• Bulging fontanelle
• Seizures - more common in encephalitis

Question 24

What symptoms are specific to septicaemia

Answer 24

Mottling of skin + hypotension + TC

Question 25

What do you do in secondary care with Suspected bacterial meningitis or meningococcal disease

Answer 25

PCR for N. men IV Ceftriaxone if they have petechial rash/spreading/purpura Lumbar puncture - unless raised ICP Fluids - esp for m.sept where they are hypotensive - restrict if raised ICP

Question 26

What are TB Lumber Puncture Findings

Answer 26

Clear/ fibrin web appearance cells per mm2: 5-1000 Lymphocytes, no neutrophils glucose low (not as low as bacterial) protein >1 Other tests: Fluorescence test, PCR

Question 27

What is the S. pyogenes Pathway

Answer 27

Asymptomatic (20-40%) Symptomatic (Pharyngitis, strepthroat) Systemic (Scarlet Fever)) → either immune sequelae (RHD, GNephritis) or invasive infection (NEC FASC) Early Stages - ScpA (C5a peptidase) Late Stages - SpyCEP (IL-8 protease) → NecFasc, only in necrotising bacteria