infection and immunity Flashcards
How to safety net febrile child
come back if: seizures unwell > 5 days rashes child looks generally unwell concerned you can't look after child
What organisms cause meningitis
<3 months group b strep e. coli listeria 3 months - 6 years n. meningitides strep pneumonia h. influenza
what are the contraindications for LP
neuro signs of inc. ICP
cardio resp fragility
thrombocytopenia
coagulopathy
Mx meningitis
- benzylpenicillin ASAP
- 3rd gen cephalosporin (+ supportive - anticonvulsants, saline)
- Dexamethasone if: v. turbid csf, CSF WCC >1000, bacteria on gram stain
don’t use steroids in meningococcal speticaemia
give ciprofolxacin prophylaxis to all household after meningococcal meningitis or h.influenza
Causes of atypical meningitis
Lyme’s disease
TB
mycoplasma
fungal
Mx encephalitis
treat all w/ IV aciclovir until cause is determined supportive care in ICU HSV1+2 - IV aciclovir VZV- aciclovir/ganciclovir CMV - ganciclovir +foscarnet EBV - aciclovir
What causes toxic shock syndrome
toxin producing staph a
group a streptococci
how does toxic shock syndrome present
fever
hypotension
widespread erythematous macular rash
NB- some staph a have PVL which causes necrotising fasciitis
after 2 weeks get desquamation of palms + soles
Mx of toxic shock syndrome
ICU
surgically debride infected areas
start BSA before cultures come back
What does impetigo look like
honey crusted lesions on nose and mouth
Mx impetifo
advice about hand washing
topical or oral abx
mx
admission
IV abx (flucloxacillin)
emollient
How does HSV present in most children
gingivostomatitis
secondary presentations (from reactivation):
cold sores
eczema herpeticum (can get overlying bacterial infection)
herpetic whitlow on skin by nails
eye problems
Which children get disseminated HSV
neonates
immunocompromised
get encephalitis and aseptic meningitis
Mx HSV
symptomatic
if severe: aciclovir and IV fluids
complications of VZV
Secondary bacterial infections - staph aureus, group a strep causing necrotising fasciitis + TSS
Encephalitis - prognosis quite good. Typically get VZV cerebllitis so present ataxic
Purpura fulminans - VZV viral Ab attack skin (also get increased risk of clot)
Mx VZV
Advice:
most contagious 1-2 days before rash
stops being contagious when everything crusted over
avoid contact w/:
pregnant women
immunocompromised
<4 weeks old
Mild disease:
oral paracetamol and emollients to stop itching (keep nails short)
moderate disease:
oral aciclovir
oral paracetamol, emollient
admit if serious complications
severe:
IV aciclovir
+ others
immunocompromised:
human VZVIg IV
Symptoms of EBV
fever tonsiliitis/pharyngitis lymphadenopathy splenomegaly maculopapular rash
Dx of EBV
atypical lymphocytes on
Monospot test (heterophile Ab positive)
seroconversion with 3 antibodies
Mx of EBV
paracetamol/ibuprofen
lasts 2-4 weeks
don’t need to stay home but avoid contact sports
come back if stridor, difficulty breathing, abdo pain
NB - ampicillin and amoxicillin cause maculopapular rash
How does CMV present
Mononucleosis like syndrome
pharyngitis
atypical lymphocytes
BUT heterophile Ab negative (unlike EBV)
what causes roseola infantum and how does it presetn
HHV6 + 7
High fever
macular rash (comes on as fever starts to wane)
what does parvovirus B19 cause
slapped cheek syndrome (erythema infectiosum)
natural hx of parvovirus b19
fever + myalgia
red cheeks after a week
lace-like purpuric rash on trunk + limbs after a week
can get aplastic crisis if underlying anaemias/thalassemia
avoid pregnant woman (get hydrops)
Mx parvovirus
Avoid pregnant women
pain killers and hydration
What can enteroviruses cause
Hand foot and mouth disease (painful vesicles)
herpangina (vesicles on soft palate and uvula)
myocarditis (rare)
enteroviral neonatal sepsis (intrapartum infection)
Features of measles
Rash
koplik’s spots on buccal mucosa
coryzal symptoms
rarely encephalitis and long term neuro damage
mx measles
NOTIFIABLE DISEASE
hydration and rest
vitamin a given if hospitalised or <2
how does measles present
parotitis + fever
if abdo pain and plasma amylase high then think pancreatic involvement
Mx measles
notifiable disease
stay away from school for 5 days after development of parotitis
warn about mumps orchitis
mx rubella
notifiable disease
low grade fever
maculopapular rash on face which lasts 3-5 days
lymphadenopathy
features of kawaski
Crash and Burn conjunctivitis rash adenopathy (cervical) strawberry tongue hands - erythema and swelling
burn - fever
systemic vasuclitis - can cause coronary aneurysm
mx kawasaki
IVIg
high dose aspirin for 8 weeks (to reduce risk of thrombosis)
(can give steroids as second line)
carry out risk assessment for MI at 8 weeks
low risk - no fruther treatment
high risk - low dose aspirin til aneurysm regress
Diagnosis of TB in children
can’t do sputum in chidlren <8 so do gastric washing
tuberculin test - induration >5mm = latent TB
Mx TB
notifiable disease
if unwell and active TB admit, if well refer to clinic
Rifampicin, isoniazid, ethambutol, pyrazinamide 4 months
pyrazinamide and ethambutol 2 months
pyridoxine (B6) given to prevent neuropathy from isoniazid
latent TB -iosniazid 6 months, rifampicin + isoniazid 3 months
Dx of HIV
> 18 months they have Ab that they’ve produced themselves so identifying this = dx of HIV
<18 months still have maternal Ig so it only proves exposure
Do HIV RNA PCR in these people
What does lyme disease look like
erythema migrans (target rash) at site of infection (painless) fever and myalgia
mx for immundeficiency
antimicrobial prophylaxis
t cell + neutrophil defects - cotrimoxazole for PCP, itraconazole for fungal stuff
B cell defects - azithromycin for recurrent bacterial infections
