Frankly my dear, I do give a damn

aka Paediatric Perplexity 016

An 18 month old girl is brought in by Gran after developing a very red rash over the last 2 days.

She was seen by her GP a few days before with fevers, sore throat and lethargy and was diagnosed as a viral infection. However the rash then came up the following day and she seemed to deteriorate…

Scarlet Fever

Q1. What is the diagnosis?

Answer and interpretation

Scarlet Fever

Q2. What organisms cause it?

Answer and interpretation

Group A Beta Haemolytic Streptococci (GABHS)

Q3. What is the characteristic rash?

Answer and interpretation

A fine scarlet red erythematous blanching rash, initially starting on the trunk before spreading to the limbs with the appearance of patchy sunburn.

The most striking characteristics of the rash is its grainy sandpaper-like texture, a pathognomic feature
You may also notice sparing around the perioral area (circumoral pallor), linear areas of pigmentation in skin creases (Pastia lines) and, after 7-10 days, desquamation of the face and hands

Scarlet Fever can also cause a strawberry tongue

Q4. What causes the Rash?

Answer and interpretation

The streptococci release a pyrogenic exotoxin toxin.

Q5. What is the prodrome?

Answer and interpretation

It usually evolves from tonsillar or pharyngeal infection with the Group A strep

However it can also follow GABHS infection of the skin (erysipelas) or lungs.

Q6. How is it spread?

Answer and interpretation

Respiratory Droplet

Q7. What is the Treatment?

Answer and interpretation

Phenoxymethylpenicillin (Penicillin V) orally twice a day for 10 days.

Q8. Is it dangerous?

Answer and interpretation

In the pre-antibiotic era Scarlet Fever had a significant mortality rate, however mortality is less than 1% if antibiotics are commenced.

Complications include pneumonia, septicaemia, myocarditis, acute rheumatic fever and post streptococcal glomerulonephritis.

Q9. What other conditions look similar?

Answer and interpretation

Kawasaki disease also presents with a fever (for at least 5 days), strawberry tongue, a rash, late desquamation and cervical lymphadentitis. However there tends to be one dominant cervical lymph node > 1.5cm, red eyes due to non-suppurative conjunctivitis and bright red, cracked lips.

Toxic shock syndrome may also produce a strawberry tongue, but lacks the perioral sparring and sandpaper texture to the rash and implies a degree of haemodynamic instability.

Slapped cheek syndrome (Fifth disease) from parvovirus B19 also produces a facial then truncal rash, however the child is well appearing, fever is less of a feature and the strawberry tongue and sandpaper quality to the rash is absent.

More pediatric perplexity


Paediatric Perplexity

Peer review: Dr Michael Baker

Emergency Medicine Physician, #FOAMed advocate and self confessed rugby tragic | @JohnnyIliff | LinkedIn

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.