Infection & Immunity Flashcards
You do a lumbar puncture and find raised proteins and low glucose. Is this likely to be due to a bacterial or a viral infection?
Bacterial
Give 5 signs of SLE.
- Malar rash.
- Discoid rash.
- Photosensitivity.
- Oral ulcers.
- Arthritis.
- Pleuritis.
- Pericarditis.
- Renal failure.
- Seizures.
- Thrombocytopenia.
What is the most common causative organism of UTI in children?
E.coli.
Give 3 signs of UTI in children.
- infants: poor feeding, vomiting, irritability
- younger children: abdominal pain, fever, dysuria
- older children: dysuria, frequency, haematuria
- features which may suggest an upper UTI include: temperature > 38ºC, loin pain/tenderness
How is urine collection done in children?
clean catch is preferable
if not possible then urine collection pads should be used
cotton wool balls, gauze and sanitary towels are not suitable
invasive methods such as suprapubic aspiration should only be used if non-invasive methods are not possible
What is the mx of UTI in children?
- infants less than 3 months old should be referred immediately to a paediatrician
- children aged more than 3 months old with an upper UTI should be considered for admission to hospital. If not admitted oral antibiotics such as cefalexin or co-amoxiclav should be given for 7-10 days
- children aged more than 3 months old with a lower UTI should be treated with oral antibiotics for 3 days according to local guidelines, usually trimethoprim, nitrofurantoin, cephalosporin or amoxicillin. Parents should be asked to bring the children back if they remain unwell after 24-48 hours
- antibiotic prophylaxis is not given after the first UTI but should be considered with recurrent UTIs
How would you treat a UTI that has been caused by Extended Spectrum Beta-Lactamases (ESBL) e.coli?
You would give meropenem.
ESBL bacteria are resistant to all penicillins and cephalosporins.
Name an organism that commonly causes osteomyelitis in children.
Staphylococcus aureus.
Give 3 signs of osteomyelitis in children.
- Joint Pain
- Lethargy
- Fever
What investigations might you do on a child who you suspect has an infected joint?
- XR.
- MRI.
- Blood cultures.
- Joint aspirate
How would you treat a child with osteomyelitis?
- flucloxacillin for 6 weeks
- clindamycin if penicillin-allergic
What bacteria commonly causes meningitis in children?
Neonates:
GBS
E.coli
Listeria monocytogenes
1m -> 6 years:
Neisseria meningitidis (meningococcus)
Streptococcus pneumoniae (pneumococcus)
Haemophilus influenzae
>6 years: Neisseria meningitidis (meningococcus) Streptococcus pneumoniae (pneumococcus)
What investigations might you do on a child who you suspect has meningitis?
FBC CRP U & E LFT blood glucose & blood gas coagulation screen culture of blood, throat swab, urine, stool rapid antigen test for meningitis organisms PCR of blood & CSF lumbar puncture
Describe the mx for a child with meningitis.
- Antibiotics
< 3 months: IV amoxicillin + IV cefotaxime
> 3 months: IV cefotaxime - Steroids
if > 1 month and Haemophilus influenzae then give dexamethasone - Fluids
treat any shock, e.g. with colloid - Cerebral monitoring
mechanical ventilation if respiratory impairment - Public health notification and antibiotic prophylaxis of contacts
ciprofloxacin is now preferred over rifampicin
- All patients should be transferred to hospital urgently. If patients are in a pre-hospital setting (for example a GP surgery) and meningococcal disease is suspected then intramuscular benzylpenicillin may be given, as long as this doesn’t delay transit to hospital.
- Intravenous dexamethasone should also be given to reduce the risk of neurological sequelae.
What is a septic screen?
A septic screen is used to check for infection, in particular meningitis:
- Blood culture
- FBC
- CRP
- Urine sample
Consider if indicated:
- CXR
- LP
- Rapid antigen screen on blood/CSF/urine
- Meningococcal and pneumococcal PCR on blood/CSF
- PCR for viruses in CSF (especially HSV and enterovirus)
Why does a child with meningococcal septicaemia develop a rash?
The purpuric rash is due to bacterial endotoxins damaging blood vessels -> vasculitis -> bleeding into SC tissue -> thrombosis and DIC.
Name 2 drugs that can be given as meningitis prophylaxis.
- Rifampicin.
2. Ciprofloxacin.
2-years-old, 2m history of malaise, pallor and reduced appetite. Occasional febrile episodes associated with a pink rash and soreness in her left thigh. Now reluctant to weight bear despite walking at 13 months. All immunisations are up to date and developmental history shows no concerns. O/E: low grade fever and cervical lymphadenopathy. ESR is significantly raised. Give 3 differentials.
- JIA.
- ALL.
- Transient synovitis.
- Septic arthritis.
3-year-old, 7-day history of high fevers. Now developed red eyes, a rash, sore mouth and throat. Miserable and unwell with a diffuse maculopapular rash on his torso. He has bilateral injected conjunctiva, red cracked lips and a strawberry tongue. 3x2cm cervical swelling and swollen reddened palms. Give 3 differentials.
- Kawasaki disease.
- Scarlet fever.
- Shingles/chickenpox.
- Measles - ask about immunisation history.
What is the diagnostic criteria for Kawasaki disease?
>5 days fever. And 4/5 of the following: - Non-purulent conjunctivitis. - Red mucous membranes - Cervical lymphadenopathy. - Rash. - Red and oedematous palms and soles/ Peeling of fingers and toes
What is Kawasaki disease?
A systemic vasculitis that affects children.
Describe the treatment for Kawasaki disease.
IV immunoglobulin and high dose PO aspirin.