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?
What organism do you suspect if child is unvaccinated and <4 years?
Neisseria Meningitides
Neisseria Meningitides and streptococcal pneumoniae should be suspected if <4 years and unvaccinated
Most common causes of meningitis in neonates?
○ Group B streptococci (gram +)
○ Listeria monocytogenes (gram +)
○ EColi (gram -)
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 (tuberculous meningitis)
What investigations should be done in a child with meningitis?
What should you do if there is meningococcal septicaemia?
Do NOT let investigations delay treatment
EXAMINATION
- A to E assessment for shock (CRT, temp, HR BP)
- Kernigs and brudzinskis
BLOODS:
FBC
Us and Es (check if they have been affected)
Glucose (see if this is causing drowsiness and to compare)
CRP
Coagulation
MICROBIOLOGY Blood cultures Urine dip to look for infection Lumbar puncture PCR to look for specific causes (Nisseria meningitides or enterovirus/HSV/HIV/TB) -Western blot for borrelia burgdorferi -Thin blood smear for malaria
If suspecting meningococcal septicaemia give dose of benzylpenicillin IV or IM (or if no rash but cant get urgent hospital transfer)
It is not appropriate to do an LP in all children, in which ones is it contra-indicated?
Contraindications for lumbar puncture
- Raised ICP or bulging fontanelle
- Coagulopathy (bleeding disorder)
- Haemodynamic instability (low perfusion)
- 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 MANAGMENT of children with bacterial meningitis?
- ANTIBIOTICS
Wide spectrum cephalosporin penetrate CSF
-50mg CEFOTAXIME
-OR
-80mg CEFTRIAXONE
+ Amoxicillin in children under 3 months (or elderly) for listeria cover - STEROIDS (ASAP before/at same time as AB)
(reduce risk of neurological complications, particularly deafness and death. Within 12 hours if cant give immediately)
-although not if <3 months
-DEXAMETHASONE 0.15mg/kg QDS might reduce the neurological sequelae particularly deafness (need to confirm with LP and consult senior first) - FLUIDS if in shock
- 20ml/kg 0.9% NaCl fluid bolus (monitor response and monitor Ca and K) - PHE should be notified (contact prophylaxis might be required) and TREAT contacts prophylactically
- SAFTEY NET AND FOLLOW UP
- follow up with pads and hearing test
- safety net: come back if any hearing or developmental problems (memory)
What is meningococcal septicaemia?
This is a sepsis caused by a meningococcus (of any type). It can occur with or without meningitis (most common is Meningitides serogroup B)
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 is the prophylactic meningitis treatment of contacts and who should be treated?
Prophylaxis (ciprofloxacin, although check guidelines) against meningococcal disease and also H influenza
- people close contact in household setting 7 days prior to onset
- transient contact only if large exposure to droplets (kissing)
- side room for 24hr after AB
REGARDLESS OF VACCINATION STATUS
How should a suspected case of meningococcal septicaemia be managed?
A to E assessment
80mg CEFTRIAXONE or 50mg CEFOTAXIME
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
PHE alert - treat contacts prophylactically
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 (meningococcal)
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
Who normally gets HSP and what seems to trigger it?
- Usually occurs in boys between the ages of 3-10
- Usually occurs after an upper respiratory tract infection -(winter more common)
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 (one of the most common causes of IgA Glomerulonephritis)
Asides from the rash what other signs might there be of HSP?
square of symptoms
- Flitting joint pain (lower limb more)
- GI symptoms (nausea/vomiting/bloody stools/can get necrotic bowel and intussusception due to vasculitis)
- Pupruric macula rash (symmetrical, buttocks/legs)
- Renal involvement (blood in urine)-nephritis 40%
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
-FOLLOW UP FOR 6 MONTHS (to check for renal impairment)
How do we prevent meningitis?
REVENTION OF MENINGITIS
• 2 months-MenB (booster at 4 months and 1 year)
• 2 months -Pneumococcus (strep pneumonia) (booster at 4 months and 1 year)
• 6in1 against H. Influenza type B
• 1 year-MenC
• Teenagers aged 13-15 years (and uni): quadrivalent vaccine (meningococcus groups A, C, W, Y)
• 65+ pneumococcal vaccination
Intrapartum screening for group B strep and AB prophylaxis
Which agent causes chicken pox?
How would you investigate chicken pox in GP?
Varicella Zoster Virus (VZV)
- normally chicken pox is clinical diagnosis however can do PCR of skin scrapings
- make sure to check for complications (breathing, walking, speach, skin)
What is the classical clinical presentation of chicken pox?
Order of events:
- FEVER (couple days before_
- MACULOPAPULAR RASH
- VESICULAR RASH
- PUSTULES AND RUPTURE
- CRUST OVER (takes about a week-longer may mean impaired immunity)
○Rash starting on head/trunk, then spread all over
○ Can also include mucosal membranes
○ SYSTEMIC UNWELLNESS
- Some children will be playing/running around
- Some children will be wheezy, fatigued and very lethargic, low appetite, headache, abdominal pain
- Females might get unpleasant vulval lesions
What is the incubation period and how long for chicken pox?
Incubation period (time taken from exposure to symptoms) is 10-21 days
How long will children be infective for with chicken pox?
4 days before the appearance of the rash and until lesions have crusted over (usually 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. safety net: return if new onset higher fever/persistantly high after couple days
- 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
- Fluids and oral intake
- Paracetamol (avoid ibo-may increase risk of complications)
- Short nails/wear mittens
- Keep them cool to help comfort with fever
- Avoid pregnant mums/immuncompromised/newborns
- Calamine lotion can soothe itching
- SCHOOL EXCLUSION from 5 days after onset of rash/when lesions crusted over (most infectious period is 1/2 days before rash
MEDICATION
Immunocompromised patients can be given VZIG prophylactically or IV acyclovir for treatment (and those with complications)
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
What are some symptoms of conjunctivitis?
Red, irritated, itchy, weeping eye
What features might make you consider a bacterial cause of conjunctivitis and what are some common agents?
If the weeping is purulent and sticky (rather than serous as in viral)
If the conjunctivitis is particularly red/irritant looking how could you consider treating it?
Chloramphenicol drops or neomycin topical ointment (could be staphylococcal)
What is general management for all infective conjunctivitis?
Cleaning with saline or water regularly is recommended and this will usually lead to the infection clearing up in 3 or 4 days
If conjunctivitis occurs in the first 48 hours after birth what should you consider?
That it might be caused by gonococcus from the mother’s genital tract
How should conjunctivitis caused by gonococcus be treated?
- Gonorrhoea is common penicillin resistant in the UK so treatment with third gen cephalosporin is advised (CEFOTAXIME)
- Sample to lab
- Really important because can cause blindness
If a baby presents with conjunctivitis 1-2 weeks after birth what organism should you consider?
Chlamydia trachomatis
