Infections: Sepsis; Kawasaki; Malaria Flashcards
Describe the pathophysiology of sepsis [+]
The causative pathogens are recognised by macrophages, lymphocytes and mast cells
These cells release vast amounts of cytokines, such as interleukins and tumor necrosis factor, to alert the immune system to the invader.
These cytokines activate other parts of the immune system. This immune activation leads to further release of chemicals such as nitrous oxide that causes vasodilation. The immune response causes inflammation throughout the body.
Many of these cytokines cause the endothelial lining of blood vessels to become more permeable.
This causes fluid to leak out of the blood into the extracellular space, leading to oedema and a reduction in intravascular volume.
The oedema around blood vessels creates a space between the blood and the tissues, reducing the amount of oxygen that reaches the tissues.
Activation of the coagulation system leads to deposition of fibrin throughout the circulation, further compromising organ and tissue perfusion. It also leads to consumption of platelets and clotting factors, as they are being used up to form the blood clots. This leads to thrombocytopenia, haemorrhages and an inability to form clots and stop bleeding. This is called disseminated intravascular coagulopathy (DIC).
Blood lactate rises as a result of anaerobic respiration in the hypo-perfused tissues with an inadequate oxygen. A waste product of anaerobic respiration is lactate.
What’s the definition of septic shock? [1]
Septic shock is diagnosed when sepsis has lead to cardiovascular dysfunction. The arterial blood pressure falls, resulting in organ hypo-perfusion. This leads to a rise in blood lactate as the organs begin anaerobic respiration.
What are the signs of sepsis? [+]
Typically presents as SHOCK:
- Tachycardia
- Tachypnoea
- Prolonged CRT
- Low BP - late sign!
- Deranged physical observations
- Prolonged capillary refill time (CRT)
- Fever or hypothermia
- Deranged behaviour
- Poor feeding
- Inconsolable or high pitched crying
- High pitched or weak cry
- Reduced consciousness
- Reduced body tone (floppy)
- Skin colour changes (cyanosis, mottled pale or ashen)
- Shock involves circulatory collapse and hypoperfusion of organs.
Describe the tx of sepsis [+]
A-E
Blood tests, including a FBC, U&E, CRP, clotting screen (INR), blood gas for lactate and acidosis
Blood cultures, ideally before giving antibiotics
Intubate and ventilate if required
Fluid resus
- 20ml/kg IV bolus of normal saline if the lactate is above 2 mmol/L or there is shock. This may be repeated.
Inotropes
IV Ceftriaxone (within 1hr)
Glucose if required
Electrolyte correction
Correction of coagulopathy
How do you give fluids if lactacte is above 2 mmol/L in paed. sepsis? [1]
IV fluids: 20ml/kg IV bolus of normal saline if the lactate is above 2 mmol/L or there is shock. This may be repeated.
If a patient is presenting with sepsis < 3 months - what are the most likely overall causes and why? [1]
What are the most likely bacterial [3] or viral [3] pathogens?
Largely unvaccinated- so more likely to be bacterial cause than older ages
Bacteria:
- GBS, E.coli or Listeria
Viruses:
- HSV, enterovirus or parechovirus
What specific drug medication would you give for a septic patient < 3 months? [3]
Ceftriaxone and amoxicillin (due to listeria risk) and consider aciclovir in neonates (due to risk of HSV)
Describe what is meant by toxic shock syndrome [1]
Describe the presenting features [4]
Toxic shock syndrome is caused by toxin-producing strains of Staphylococcus aureus and GAS.
Consider in a child if:
* Fever > 38.9
* Shock with hypotension
* Widespread erythematous rash
* End organ dysfunction
If you suspect toxic shock syndrome, which antiobiotic do you add to the management plan? [1]
Add clindamycin
- Ceftriaxone & clindamycin
The traffic light system is used to stratify risk of sepsis in children.
What would determine green / low risk with regards to:
- Colour (of skin, lips or tongue)
- Activity
- Circulation and hydration
- Other
The traffic light system is used to stratify risk of sepsis in children.
What would determine yellow / medium risk with regards to:
- Colour (of skin, lips or tongue)
- Activity
- Circulation and hydration
- Other
The traffic light system is used to stratify risk of sepsis in children.
What would determine red / high risk with regards to:
- Colour (of skin, lips or tongue)
- Activity
- Circulation and hydration
- Other
TOMTIP: It is worth remembering that all infants under 3 months with [presentation] need to be treated urgently for sepsis, until proven otherwise.
It is worth remembering that all infants under 3 months with a temperature of 38ºC or above need to be treated urgently for sepsis, until proven otherwise.
Which are the most typical organism that causes pneumonia in children? [1
Name 3 others [3]
Most commonly by Streptoccocus pneumoniae
Also
- GAS
- Staph aureus
- Klebsiella
- Mycoplasma
How would you treat paed pneumonia? [2]
Co-amoxiclav (and azithryomycin to treat mycoplasma)
Name a complication of pneumonia that can occur [1] and the treatment [2]
Empyema (pus builds up in the pleural space)
- Tx with chest drain +/- urokinase OR VATs
How would you manage septic arthritis in a child? [2]
Wash-out joint and send samples for culture
IV Abx until improving - switch to oral. Minimum of 2-3 weeks; often co-amoxiclav
Why do you use an MRI as first line osteomyelitis Ix? [1]
What is the treatment? in children? [2]
**X-rays **often only show evidence of infection after 10 day
IV Abx: often co-amoxiclav or flucloxacillin in older child for 4-6 weeks
Which infections in returning travellers do you need to consider for children? [4]
Which are have significant incubation periods? [2]
Malaria
Typhoid - 2/3 weeks
Dengue
Hep A - 2/6 weeks
Describe the presentation of malaria in children (non-severe [3] and severe [5])
Can be non-specific:
- Fever, lethargy, D&V
If severe:
- Anaemia
- Respiratory distress
- Coma and seizures if cerebral
- Hypoglycaemia
Consider in any unwell child who has travelled to malarial area!
How do you treat malaria in non-severe [1] and severe disease [1] in children?
Non-severe:
- Combination therapy: coartem (artemether - lumefantrine)
- Primaquine to prevent disease relapse in liver if P. ovale or vivax
Severe:
- Artesunate IV
NB: Vivax and ovale have
TOM TIP: If you come across a child with a fever persisting for more than 5 days, think of []!
TOM TIP: If you come across a child with a fever persisting for more than 5 days, think of Kawasaki disease!
Describe the presentation of Kawaski disease [6]
- Widespread erythematous maculopapular rash and desquamation (skin peeling) on the palms and soles.
- fever for 5 days ++
- strawberry tongue
- cracked lips
- Cervical lymphadenopathy
- Bilateral conjunctivitis
NB: CRASH
CRASH
C - Conjunctival injection (bilateral)
R - Rash (polymorphous exanthema)
A - Adenopathy (cervical lymphadenopathy, often unilateral)
S - Strawberry tongue and oral mucosal changes (e.g., cracked lips)
H - Hand and foot changes (erythema of palms and soles, followed by desquamation)
Describe the three stages of Kawasaki disease [3]
Acute phase:
- The child is most unwell with the fever, rash and lymphadenopathy. This lasts 1 – 2 weeks.
Subacute phase:
- The acute symptoms settle, the desquamation and arthralgia occur and there is a risk of coronary artery aneurysms forming. This lasts 2 – 4 weeks.
Convalescent stage:
- The remaining symptoms settle, the blood tests slowly return to normal and the coronary aneurysms may regress. This last 2 – 4 weeks.
How do you manage Kawasaki disease? [3]
High dose aspirin to reduce the risk of thrombosis
IV immunoglobulins to reduce the risk of coronary artery aneurysms
Offer regular ECHOs to avoid coronary artery aneurysms
TOM TIP: Kawasaki disease is one of the few scenarios where aspirin is used in children. Aspirin is usually avoided due to the risk of [] This is a unique fact that examiners like to test.
TOM TIP: Kawasaki disease is one of the few scenarios where aspirin is used in children. Aspirin is usually avoided due to the risk of Reye’s syndrome. This is a unique fact that examiners like to test.
