Viral Exanthemas Flashcards
What does exanthem mean?
eruptive widespread rash.
How many viral exanthemas are there?
6
What are the 6 viral exanthemas?
First disease: Measles
Second disease: Scarlet Fever
Third disease: Rubella (AKA German Measles)
Fourth disease: Dukes’ Disease
Fifth disease: Parvovirus B19
Sixth disease: Roseola Infantum
What is the measles caused by?
Measles virus
What is the type of transmission of measles?
It is highly contagious via respiratory droplets
How long does it take for symptoms to start after exposure in measles?
10 – 12 days after exposure
What are the symptoms of measles?
- Fever
- Coryzal symptoms (The meaning of CORYZA is an acute inflammatory contagious disease involving the upper respiratory tract; )
- conjunctivitis
4.Koplik spots
5.Rash
Where are koplik spots located when having measles?
on the buccal mucosa
When do the koplik spots appear in measles?
2 days after the fever
What is unique about koplik spots?
They are pathognomonic for measles, meaning if a patient has Koplik spots, you can diagnose measles.
Where does therash typically start in measles?
The rash starts on the face, classically behind the ears, 3 – 5 days after the fever. It then spreads to the rest of the body
How does a measles rash typically present?
The rash is an erythematous, macular rash with flat lesions.
How long do measles take to self resolve?
7-10 days after symptoms
How long should children isolate for after measle symptoms resolve?
4 days
What percent of measle patients will develop complications?
30%
What are 8 complications involved with measles?
- Pneumonia
- Diarrhoea
- Dehydration
- Encephalitis
- Meningitis
- Hearing loss
- Vision loss
- Death
Which of the viral exanthemas are notifiable diseases?
1) measles
2) Scarlet fever
3) rubella
What is the infective agent in Scarlet fever?
Group A Strep (Streptococcus pyogenes)
Describe the rash seen in Scarlet fever:
red-pink blotchy, macular rash with rough sandpaper skin that starts on the trunk and spreads outwards
Give 7 presentations associated with Scarlet fever:
1) fever
2) lethargy
3) macular rash with sandpaper skin
4) flushed face
5) sore throat
6) strawberry tongue
7) cervical lymphadenopathy
Strawberry tongue is associated with which infectious disease?
Scarlett fever
What is the treatment for Scarlet fever?
phenoxymethylpenicillin for 10 days
Give 2 complications of Scarlet fever:
1) acute rheumatic fever
2) post-Streptococcal glomerulonephritis
What is the guidance around Scarlet fever and school?
children with Scarlet fever should be kept off school until 24 hours after starting antibiotics
What is the infectious agent in rubella?
rubella virus
What is the mode of transmission in rubella?
direct - respiratory droplets
How long after exposure do symptoms start in rubella?
2 weeks
Describe the rash seen in rubella:
a milder erythematous rash compared to measles which starts on the face and spreads to the rest of the body
How long does the rubella rash typically last?
3 days
Give 5 presentations associated with rubella infection:
1) erythematous rash
2) mild fever
3) joint pain
4) sore throat
5) lymphadenopathy
What is the recommended guidance for children with rubella and school attendance?
children should stay off school for at least 5 days after the rash appears
Give the triad seen in congenital rubella syndrome:
1) deafness
2) blindness
3) congenital heart disease
What are 2 possible complications of rubella?
- Thrombocytopenia
- Encephalitis
What is another name for parovirus B19?
slapped cheek syndrome
Describe the natural history of parovirus B19 infection:
1) begins with mild fever, coryzal symptoms and muscle aches
2) on day 2-5, a diffuse red rash appears on the cheeks
3) a few days later, a reticular, mildly erythematous rash affects the trunk, and limbs which is itchy
What does a reticular rash look like?
net-like
How long do symptoms in Parovirus B19 last?
1-2 weeks
What is the guidance on children with parovirus B19 infection and school attendance?
it is infectious prior to the rash forming but once the rash has formed, they are no longer infectious and can attend school
What three groups of patients are at risk of complications in Parovirus B19 infection?
1) pregnant women
2) immunocompromised patients
3) patients with haematological problems (sickle cell anaemia, thalassaemia, hereditary spherocytosis, haemolytic anaemia)
Give 4 complications associated with parovirus B19:
1) aplastic anaemia
2) encephalitis or meningitis
3) pregnancy complications e.g. foetal death
4) hepatitis, myocarditis and nephritis (in rare cases)
What is the management of parvovirus B19?
Healthy children and adults have a low risk of any complications and are managed supportively with plenty of fluids and simple analgesia.
What is the infectious agent in roseola infantum?
human herpes virus 6 and less frequently human herpes virus 7
How long does it take for symptoms to begin in roseola infantum following exposure?
1-2 weeks
What is the first symptom seen in roseola infantum?
sudden high fever (up to 40 degrees) which disappears suddenly
How long does the rash last for in roseola infantum last?
1-2 days
Describe the rash seen in roseola infantum:
mild erythematous macular rash across the arms, legs, trunk and face which is not itchy
True or false: children with roseola infantum can continue going to school
true
What is the main complication associated with roseola infantum?
febrile convulsions
What may immunocompromised patients with roseola Infantum may be at risk of?
Immunocompromised patients may be at risk of rare complications such as myocarditis, thrombocytopenia and Guillain-Barre syndrome.