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Discussion Starter · #1 ·
quick review, P630

Child with fever later develops red rash on face that spreads to
body:
Erythema infectiosum/fifth disease (“slapped cheeks”
appearance, caused by parvovirus B19

isn't this HHV6- roseola infantum-exanthema subitum?




Thanks for helping :)
 

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Nope, its correct. Fifth disease begins as a fever, later causing a "slapped cheek" rash that spreads to the trunk to form a reticular rash.
By the time the rash appears, the child is no longer infectious.
 

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Discussion Starter · #3 ·
Hi, thanks for replying,

so how can I differentiate these 2 diseases?
are they very similar or am I missing something?

Thanks again
 

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so how can I differentiate these 2 diseases?
are they very similar or am I missing something?

Thanks again
Parvovirus B19 causes fifth disease/erythema infectiosum in children which presents with fever and a characteristic slapped cheek rash followed by a fine reticular rash on the trunk.
It can have a different presentation in fetuses and adults though. In fetuses, it can cause pure red cell aplasia, aplastic crisis or even hydrops fetalis which can cause them to be still born.
In adults, it presents very similarly to Rheumatoid arthritis.
Parvovirus B19 can also cause aplastic crisis in individuals with Beta Thalessemia Major, Hereditary spherocytosis and Sickle cell disease.

Human Herpes Virus 6/7 on the other hand causes Exanthem subitum (also called Roseola infantum) which presents with rash, high fever and febrile seizures.

 

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so how can I differentiate these 2 diseases?
are they very similar or am I missing something?

Thanks again
Parvovirus B19 - single stranded DNA virus - three subgroups affected

1. In utero - hydrops fetalis(due to red cell appasia)
2. Infants - Slapped cheek appearance(rash) and "concurrent" fever
3. Adults - Migratory polyarthritis with fever

Bonus - Causes red cell aplasia in patients with sickle cell disease/ beta thal/ hereditary spherocytosis

HHV-6 - Roseola - dsDNA virus

Cause high fever in infants which is followed by whole body rash

Diff - Roseola - the rash and fever is doesn't happen simultaneously - rash occurs after the fever is over

Parvovirus B19 - concurrent rash + fever
 
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