exanthemata

Question 1

the 6 classical exanthemata diseases

Answer 1

1. measles
2. scarlet fever
3. rubella-german measles
4. fourth diesease aka nothing
5. parvovirus B19=slapped cheek disease
6. Roseola infantum=exanthemata subitum

Question 2

what causes measles

Answer 2

mobilivirus

Question 3

what causes scarlet fever

Answer 3

group a beta haemolytic strep pyogenes

Question 4

what causes rubella

Answer 4

rubivirius

Question 5

what causes roseola infanatum

Answer 5

human herpes virus 6

Question 6

what is a macule rash

Answer 6

can be seen but not felt

Question 7

what is a papule lesion

Answer 7

can be felt and seen

Question 8

what is a maculapapular rash

Answer 8

mix of macule and papule so can feel some bits

Question 9

how is exanthemata dx

Answer 9

serology IgM for all
molecular
-PCR for measles

Question 10

measles transmission

Answer 10

• droplet spread by respiratory route
• conjunctival contaminaion
  v. contaigous

Question 11

symptoms and timeline of measles

Answer 11

-incubation 7-18 days
-10days to prodrome
-prodrome for 4 days
-at 14 days get a rash
(aka appears on day 4)

Question 12

clinical features of measles

Answer 12

-prodrome 2-4 days
-day 4 must have fever and BLANCHING maculopapular rash
plus on of 3 c’s
-coryza
-conjunctivits
-cough
also
-koplik spot 2 days before rash

Question 13

what is the rash in meaasles

Answer 13

• blanching maculopapular rash
• starts behind the ears
• fades leaving capillary staining
• fine desquamation
• soles and palms spared

Question 14

measles severe manifestation

Answer 14

• pulmonary invovlement- severe chest infection 90% of cases, bronchiolitis and giant cell pneumonia
• encephalitis
• modified and atypical forms in immunocompromised

Question 15

x-ray of pulmonary measles

Answer 15

hyperinflation and diffuse fluffy infiltrates

Question 16

when is MMR vaccine given

Answer 16

2 doses 12 months and 3-5 years

Question 17

severity of rubella

Answer 17

mild illness with few severe manifestations

Question 18

clinical features of rubella

Answer 18

• rash and illness on same day usually week incubation
• fever
• lymphadenopathy post ear

Question 19

how long does rash last for rubella

Answer 19

3 days without staining

Question 20

what are the complications of rubella

Answer 20

• reactive arthritis in adults
• congenital rubella syndrome
• thrombocytopaenia
• guillain barre
• encephalitis

Question 21

what is congenital rubella syndrome and when is the risk greatest

Answer 21

if the foetus is exposed to rubella

<10 weeks 90% risk

Question 22

transient features of CRS in foetus

Answer 22

hepatitis
jaundice
rash
thrombocytopaenia
anaemia
lymphadenopathy

Question 23

permanent features of CRS in the foetus

Answer 23

classic triad

• patent ductus arteriosus
• cataracts
• senorineural deafness

also neuro eg micropcephaly

Question 24

developmental features of CRS potenitally

Answer 24

• increased risk of insulin dependent diabetes
• thyroid disease
• progressive hearing or visual loss

Question 25

prevents of CRS

Answer 25

Immunisation before pregnancy

Question 26

what does parvovirus cause in adults

Answer 26

arthropathy in adults-reactive arthritis

Question 27

clinical features of parvovirus in children

Answer 27

- fever then rash | - slapped cheek rash then 1-2 days later get a generalised rash

Question 28

complications of parvovirus

Answer 28

- infects red cell precursors - aplastic crisis in patients with pre-existing haemolytic anaemia eg sickkle cell - chronic infection in immunocompromised

Question 29

what does parvovirus do to foetus

Answer 29

-foetal anaemia-hydrops fetalis in 5% maternal infection

Question 30

how does roseola infantum present

Answer 30

-high fever for 4-5 days -when fever falls get a rash -scattered maculopapular rash on chest, back and limbs spares feet and hands

Question 31

scarlet fever type of toxin

Answer 31

erythrogenic toxin

Question 32

clinical onset of scarlet fever

Answer 32

- rash appears 1-2 days after onset of a sore throat | - assoc. to pharyngeal infection

Question 33

what type of rash is scarlet fever

Answer 33

- face-circumoral sparing - blanching rash - elevates around hair follicles-sandpaper - capillary haemorrhage in skin folds Pastia's lines - strawberry tongue - desquammation

Question 34

immune complications of scarlet fever

Answer 34

-rheumatic fever -post strep glomeruloneprhitis but now rare

Question 35

what is rheumatic fever

Answer 35

-multi system autoimmune disorder occurring 3 weeks after pharyngeal infection

Question 36

features of rheum fever

Answer 36

``` pancarditis arthritis chorea-prepubertal subcutaneous -nodules erythema marginatum ```

Question 37

long term complication of rheumatic fever

Answer 37

damage to heart valves cause rheumatic heart disease at risk of endocarditis

Question 38

strep pyogenes clinical features

Answer 38

- ssti eg erysipelas, cellulitis - strep throat - if makes erythrogenic toxin get scarlet fever

Question 39

treatment of strep pyogenes

Answer 39

antibiotics means rarely develop scarlet fever anymore