Infections Flashcards
What % of cases of meningitis occur in children under the age of 15?
75%
What is the most common causative organism of meningitis?
Neisseria Meningitides
What are some other common causative organisms of meningitis?
Streptococcus pneumonias
Haemophilus Influenza B
Meningococcus C
**The last 2 are both now vaccinated against and so their incidence has dropped
How does infection of the meninges occur, and why is this more likely to occur in children?
Usually there is an infection of the nasopharyngeal mucosa first and then this infection gets into the blood. Because in children the blood brain barrier (BBB) is less developed these bugs are more likely to reach the meninges and cause infection
Infection of the meninges leads to leaking of proteins and cerebral oedema as well as inflammation of the blood vessels in the brain (cerebral vasculitis)
What symptoms are likely to be present in a child with meningitis and what might make diagnosis more difficult?
Photophobia, neck stiffness and headache are the classical distinguishing symptoms but the young child (infant) might not have these making diagnosis more difficult.
They might have NON-SPECIFIC SYMPTOMS OF INFECTION
- Fever, malaise, vomiting, anorexia
OTHER MENINGITIC SIGNS:
- Seizures, irritability, drowsiness, disorientation, altered mental state, bulging fontanelle, papilloedema, focal neurological signs
What investigations should be done in a child with meningitis?
Do NOT let investigations delay treatment
BLOODS: FBC, U&E, Glucose, CRP, Coag, Cultures
Infection screen (urine dip)
LP
It is not appropriate to do an LP in all children, in which ones is it contra-indicated?
Raised ICP Coagulopathy Haemodynamic instability Focal neurological signs or focal seizures (more suggestive of TB meningitis) Infection of skin at LP site Respiratory insufficiency
What is the ultimate concern in children with meningitis and what signs are there of this?
SHOCK (that might be septic or neurogenic in origin but is ultimately distributive in type) Incr HR Decr BP (near fatal) Increased RR Poor CRT Cold, mottles, clammy skin Poor urine output Cyanosis THESE CHILDREN NEED IMMEDIATE RESUSCITATION
What is the antibiotic regimen in children with meningitis?
80mg CEFTRIAXONE
OR
50mg CEFOTAXIME
+ Amoxicillin in children under 3/12 (listeria cover)
Mild cases might be able to be treated with BenPen
Other than antibiotics what other management stages will be needed in a child with meningitis?
PHE should be notified (contact prophylaxis might be required)
STEROIDS (do NOT use in <3/12) - DEXAMETHASONE 0.15mg/kg QDS (this reduces neurological sequelae)
What is meningococcal septicaemia?
This is a sepsis caused by a meningococcus (of any type). It can occur with or without meningitis
What are some signs and symptoms of meningococcal septicaemia?
NON-BLANCHING PURPURIC RASH (this is very concerning) Increased HR Increase RR FEVER Poor urine output Increased CRT ...Start thinking SHOCK
What type of meningococcal organism is most likely to cause septicaemia?
Meningitides serogroup B
How should a suspected case of meningococcal septicaemia be managed?
80mg CEFTRIAXONE or 50mg CEFOTAXIME
PHE alert - treat contacts prophylactically
Resuscitation - 20ml/kg 0.9% NaCl fluid bolus (monitor response and monitor Ca and K)
If child is less than 3/12 give amoxicillin to cover for listeria
How should non-blanching rash lesions be referred to occurring to their size?
<3mm = petechial 3-10mm = purpura >10mm = ecchymosis
Why do non-blanching rashes occur?
Vascular disorders (immune complex vasculitis) Platelet disorders Endotoxin release from bacteria
What are some common differentials in a child with a non-blanching rash?
MENINGOCOCCAL SEPTICAEMIA - always work to rule this out
HENOCH-SCHONLEIN PURPURA (HSP) - is another key differential
Where is the rash usually located in children with HSP?
Over the legs and buttocks
What is a common presenting clinical picture of HSP?
Usually occurs in boys between the ages of 3-10
Usually occurs after an upper respiratory tract infection
What other systemic problems can HSP cause?
It is a type of IgA complex disease - these complexes being deposited in the skin capillaries is what causes the rash
They can also be deposited in the NEPHRONS (IgA Glomerulonephritis)
Asides from the rash what other signs might there be of HSP?
Fever
Symmetrical rash over buttocks and legs
Joint pain and swelling particularly of the ankles and knees
Abdominal pain (haematemeiss, maleana, intussusception)
Haematuria
Nephrotic syndrome (Rare)
What treatment options are there for HSP?
Usually treatment is supportive and the disease will be self limiting
Monitor for kidney function
CORTICOSTEROIDS sometimes given but therapeutic value is unclear
How should meningococcal septicaemia be dealt with in the GP?
Give a dose of IM BenPen and send to hospital urgently (Ambulance)
Which agent causes chicken pox?
Varicella Zoster Virus (VZV)
What is the classical clinical presentation of chicken pox?
Children vary very much in how unwell they are. (Can have wheeze, fatigue, breathlessness, malaise, loss of appetite or be completely fine)
Usually there will be a fever for a couple of days and then a MACULOPAPULAR RASH will develop that will turn into VESICULAR RASH that usually starts on the head/trunk and then will spread all over the body. ITCHY++
The vesicles will burst and then scab over
What is the incubation period for chicken pox?
2 weeks (10-21 days)
How long will children be infective for with chicken pox?
4 days before the appearance of the rash and 5 days after the rash first appeared
What are some complications of chicken pox?
USUALLY VERY UNCOMPLICATED
- Infection of the lesions with group A staph - can lead to toxic shock or necrotising fasciitis
- Encephalitis - commonly of the cerebellum (cerebellitis) - the prognosis for this is actually quite good
- Purpura fulminans - widespread vasculitis and necrosis
- Pneumonia
How should children with chicken pox be managed?
SUPPORTIVE
- Short nails prevent bad excoriations
- Keep them cool to help comfort with fever
- Calamine lotion can soothe itching
- SCHOOL EXCLUSION from 5 days after onset of rash
Immunocompromised patients can be given VZIG prophylactically or IV acyclovir for treatment
When does conjunctivitis usually occur in a child’s life?
It is a common infection and can occur at any time. There is a notable peak in the neonatal period due to infections obtained from the birth canal