Infectious Flashcards
What is this an image of?
Scarlet fever
What microorganism causes Scarlet fever?
Group A B-haemolytic streptococci - usually Streptococcus pyogenes
What are the features of scarlet fever?
fever: typically lasts 24 to 48 hours
malaise, headache, nausea/vomiting
sore throat
‘strawberry’ tongue
rash
fine punctate erythema (‘pinhead’) which generally appears first on the torso and spares the palms and soles
children often have a flushed appearance with circumoral pallor. The rash is often more obvious in the flexures
it is often described as having a rough ‘sandpaper’ texture
desquamination occurs later in the course of the illness, particularly around the fingers and toes
2-6 yrs old
How do we manage Scarlet Fever?
Management
oral penicillin V for 10 days
patients who have a penicillin allergy should be given azithromycin
children can return to school 24 hours after commencing antibiotics
Notify PHE
What are the complications of Scarlet Fever?
- otitis media: the most common complication
- rheumatic fever: typically occurs 20 days after infection
- acute glomerulonephritis: typically occurs 10 days after infection
- invasive complications (e.g. bacteraemia, meningitis, necrotizing fasciitis) are rare but may present acutely with life-threatening illness
How can we differentiate Kawasaki’s syndrome and Scarlet Fever?
Kawasaki typically presents in children 5 years old or younger and with a higher temperature of around 39 degrees C.
What is the school exclusion advice for some common infectious diseases in children?
AdviceCondition(s)
No exclusion:
Conjunctivitis
Fifth disease (slapped cheek)
Roseola
Infectious mononucleosis
Head lice
Threadworms
Hand, foot and mouth
24 hours after commencing antibiotics: Scarlet fever
2 days after commencing antibiotics (or 21 days from onset of symptoms if no antibiotics ): Whooping cough
4 days from onset of rash: Measles
5 days from onset of rash: Rubella
All lesions crusted over: Chickenpox*
5 days from onset of swollen glands: Mumps
Until symptoms have settled for 48 hours: Diarrhoea & vomiting
Until lesions are crusted and healed, or 48 hours
after commencing antibiotic treatment: Impetigo
Until treated: Scabies
Until recovered: Influenza
What are the signs and sx of whooping cough?
Incubation period: 5-10 days
Catarrhal phase: Coryzal prodrome, Low grade fever
Paroxysmal phase: clusters of rapid coughs - worse at night and after feeding (>=14 days), long inspiratory effort with a whoop, central cyanosis, vomiting (post-tussive emesis) and exhaustion, apnoea spells, subconjuctival haemorrhages, anoxia - syncope and seizures, lymphocytosis
Convalescent phase: Gradual recovery 2-3 weeks/months
What pathogen causes whooping cough?
Gram negative Bordatella Pertussis
What are Ix for whooping cough?
Bedside: Obs
Bloods: FBC - WBC check for lymphocytosis, CRP
Swab: Nasal swab MCS for Bordetella Pertussis, PCR and serology testing?
What is the management for whooping cough?
- Admit if under 6 months
- Notify public health England
- Check guidelines and local policy
- Give oral macrolide Abx if cough started within 21 days of presentation - clarithromycin, azithromycin, erythromycin
- Offer household contacts Abx prophylaxis
- Exclude from school for 48 hrs after commencing Abx or 21 days after onset of sx if no Abx
What are the complications of whooping cough
Subconjunctival haemorrhage
Pneumonia (recurrent chest infections)
Bronchiectasis
Seizure
What vaccines would a woman be offered during the pregnancy?
Influenza - any time during the pregnancy
Pertussis - 16-32 weeks pregnant
How would a congenital cytomegalovirus (CMV) infection present?
Microcephaly
Low birth weight
Hepatosplenomegaly
Petechial rash
Seizures
Jaundice
Anaemia
Later: hearing loss, learning disability, vision impairment, cerebral palsy
In a child with limp/hip pain and fever, with a past cold what do you need to rule out?
Septic arthritis
According to the Kocher criteria, there is a 3% chance that a child with an acutely irritable hip and fever >38.5ºC has septic arthritis, warranting urgent assessment with the possibility of synovial aspiration.
What are the rules on school exclusion for non-bullous impetigo?
A child with impetigo should be excluded from school until the lesions are crusted and healed or 48 hours after commencing antibiotic treatment
What pathogens typically cause early onset sepsis and late onset sepsis respectively in the neonate?
a) Neisseria meningitidis
b) Streptococcus agalacticae
c) Staphylococcus epidermis
d) Staphylococcus aureus
Late-onset sepsis normally occurs due to hospital acquired pathogens such as Staphylococcus epidermidis and Staphylococcus aureus.
The most likely pathogen causing early onset sepsis is Group B Strep (Streptococcus agalacticae) which is a common commensal of the female genital tract.
What are the RF for Group B Streptococcus infection in the neonate?
prematurity
prolonged rupture of the membranes
previous sibling GBS infection
maternal pyrexia e.g. secondary to chorioamnionitis
What are the Ix for Measles?
1st: measles specific IgM and IgG serology (ELISA) is most sensitive 3-14 days after onset of the rash
2nd: measles RNA detection by PCR best for swabs taken 1-3 days after rash onset
What is the Mx for measles?
Supportive care which will normally include an antipyrexial
Vitamin A in all children under 2
Ribavarin may reduce the duration of symptoms but its use is not routinely recommended
What are the features of kawasaki disease?
Conjunctivitis
Rash
Edema/Erythema of hands and feet
Adenopathy (cervical, commonly unilateral)
Mucosal involvement (strawberry tongue, oral fissures etc)
5 day < Hx of fever
What is the treatment for Kawasaki disease?
Aspirin
Intravenouos immunoglobulin (gamma globulin)
