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
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 you decide the conjunctivitis is bacterial how could you consider treating it?
Chloramphenicol drops or neomycin topical ointment
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)
If a baby presents with conjunctivitis 1-2 weeks after birth what organism should you consider?
Chlamydia trachomatis
How should conjunctivitis caused by chlamydia be investigated and how should it be treated?
Can be investigated using immunofluorescence screening
Should be treated with oral erythromycin
What is the cause of infectious mononucleosis?
EBV
What affect does EBV have and what malignancy is it associated with?
It affects the pharyngeal epithelial cells and B cell lymphocytes
- It’s effect on B lymphocytes also causes its link with Burkitt’s Lymphoma
Which age of children does infectious mononucleosis most commonly occur in?
Peak in adolescence due to its common route of spread (kissing)
- AKA the kissing disease
What are some common clinical features of infectious mononucleosis?
Fever
Malaise
Tonsilopharyngitis - this can be extensive and very painful sometimes limiting oral intake and very rarely breathing
Lymphadenopathy (prominent cervical lymphadenopathy is key feature)
Petechiae on soft palate
HEPATOSPLENOMEGALY (good diagnostic clue)
Maculpapular rash
Jaundice
What investigations should you do in a child who you suspect to have infectious mononucleosis?
Seroconversion of IgG and IgM to EBV
Positive Monospot test
Atypical lymphocytes of BLOOD FILM (Big T cells)
How long does infectious mononucleosis last?
Symptoms usually last 1-3 months then resolve
How should we manage infectious mononucleosis?
Symptomatic treatment - disease is self-limiting
If considerable obstruction consider corticosteroids
Treat concurrent bacterial infection of tonsils with penicillin
What should you never give someone who has infectious mononucleosis?
AMOXICILLIN or AMPICILLIN
It will cause a florid maculopapular rash when there is an EBV infection
If a child has a prolonged fever what should you always suspect?
Kawasaki’s disease
What is Kawasaki’s disease?
It is a VASCULITIS with mucocutaneous lymph node involvement
Who does Kawasaki’s disease usually affect?
Children between 6 months and 4 years of age (peak incidence at the end of the first year)
What clinical features must be present to make a diagnosis of Kawasaki’s disease?
A fever that has been present for 5 days + 4/5 of
- Conjunctivitis
- Mucositis / irritation around the mouth and lips
- Desquamation / redness of the hands and feet
- Cervical lymphadenopathy
- Polymorphous rash
What investigations should you do if you suspect a child has Kawasaki’s disease?
There is no specific diagnostic test for Kawasaki’s disease but you should always do an ECHOCARDIOGRAM?
What is a potentially fatal complication of Kawasaki’s disease?
Coronary artery aneurysms - this is why you should always do ECHOCARDIOGRAM to rule it out (affects approximately 1/3 of children in the first 6 weeks of disease)
What treatments should be given for Kawasaki’s disease?
IVIG
High dose aspirin
Echo monitoring
Why is aspirin not normally given in children?
Risk of REYE’S SYNDROME
- Encephalopathy in children
***Should still give aspirin in Kawasaki’s
In what way will otitis media present?
It will either be acute or recurrent - important to get an idea of which one because recurrent OM is more at risk of glue ear and hearing loss
What age are children more susceptible to acute OM and why?
6-12 months because they have short eustachian tubes that don’t flush out contents as effectively
When should you consider examining the ears in a child?
Examine in every child with a fever
Ear infections are really common and fairly easy to treat
What will you see on otoscope examination in OM?
A bulging tympanic membrane - loss of the light reflex as the middle ear has become filled with fluid
What symptoms will children with OM present with?
Ear pain (otalgia) Coryzal symptoms - current or preceding Fever Irritation Tugging of the ears Hearing loss Discharge from the ear (if membrane has ruptured)
What common pathogens cause OM?
RSV, Rhinovirus, Pneumococcus, HiB and mortadella catarrhalis
What possible complications are there of OM?
Mastoiditis and meningitis can both occur
When should you consider treatment for OM?
if the symptoms persist for 4 days or longer or don’t improve
if there is purulent discharge from ear
If child is immunocompromised
if they are systemically unwell?
Otherwise it is probably self limiting
How should OM be managed?
Advise analgesia regimen
Abx can be given - they reduce pain but not the duration of the disease. Consider AMOXICILLIN 5days
What is the concern if the child keeps having recurrent ear infections?
That this will lead to ear infection with effusion (OME)
Also known as glue ear or serous otitis media
How does recurrent OM present?
Multiple, distinct episodes of OM
Other than that might be asymptomatic apart from some hearing loss
In who is glue ear more common?
Children between the ages of 2-7
In glue ear how will the ear appear on otoscope examination?
The membrane will look DULL and retracted
What management should you consider for glue ear?
Usually the effusion will resolve spontaneously but if it does not or it is causing problems (e.g. hearing problems) can consider GROMMETS
Also consider an adenoidectomy - the adenoids can act as a reservoir for bugs that can spread to the eustachian tubes and cause recurrent infections.
What are the symptoms of preseptal cellulitis?
Fever + Redness + Tenderness + Oedema of the eyelid
UNILATERAL … if it is bilateral then consider other causes
What is the likely causative organism for orbital cellulitis?
DEPENDS ON AGE OF CHILD
- if young and unimmunised consider HiB
In older children it is more likely to be caused by spread from paranasal sinuses (so staph or strep infections) or dental abscesses
What complication of orbital cellulitis should you be concerned about? What are some signs of this?
Involvement of the orbit
Proptosis / exophthalmos
Painful / limited ocular movement
Reduced visual acuity
What investigations should you do in someone who has preseptal cellulitis?
Inflammatory markers CRP and ESR
Swabs of the site for specific organism
Consider blood cultures in orbital
Consider CT in orbital
How should preseptal and orbital cellulitis be managed?
They should all be referred to secondary care services - orbital cellulitis is an emergency and should be sent in immediately
ABX
Preseptal cellulitis can be managed with oral co-amoxiclav
Orbital cellulitis will require admission and IV abx
What is the causative agent of impetigo?
Staphylococcus aureus
Where does impetigo occur and how infectious is it?
usually occurs around the nose and the mouth
It is VERY infectious
Can also occur on the neck and hands
How does an impetigo rash appear?
It will initially be macular and then will become vesicular/pustular. As these vesicles rupture they will scan over with a HONEY COLOURED SCAB - this is classical of impetigo
How do we treat impetigo?
HYGIENE - advise on good hand washing, not towel sharing or sharing any personal care products, avoid scratching and consider washing toys
Stay off school/pre school for 48hours after starting abx
Usually topical FUSCIDIC acid (three time a day for 5 days) is enough. If the rash is more widespread then consider oral treatment
FLUCLOXACILLIN 125-250mg QDS for 7 days
