Paediatric rashes and exanthems — SAQ

Stem

A 3-year-old with incomplete MMR presents with 4 days of fever, cough, coryza and red eyes. Today a cephalocaudal maculopapular rash appears. A second child in clinic has fever for 6 days with cracked lips, strawberry tongue and swollen hands. A third has non-blanching purpura and looks shocked.

Questions

a) What is the most likely diagnosis in the first child, and which bedside features support it? (2 marks)

b) List key differentials for fever-and-rash and the red-flag diagnoses that must be excluded before discharge. (3 marks)

c) Outline immediate management of the third (purpuric) child and disease-specific therapy for the second (mucocutaneous) child. (3 marks)

d) What public-health and supportive actions apply to measles, and what complications matter most? (2 marks)

Model outline

• a) Measles: 3 Cs, day-3–4 cephalocaudal rash, incomplete vaccine; look for Koplik.
• b) Roseola, fifth disease, rubella, scarlet, HFMD, drug eruption; exclude meningococcus, Kawasaki, SJS.
• c) Purpura: immediate antibiotics + resuscitate; Kawasaki: IVIG + aspirin.
• d) Isolate, notify, vitamin A per guidance, contact MMR/PEP; pneumonia, encephalitis, SSPE, death risk.