A 2-year-old child presents with a 2-day history of high fever and irritability. The fever resolves abruptly, and a diffuse, blanching, rose-pink maculopapular rash appears on the trunk. The child is otherwise well. What is the causative organism?
- A Rubella virus
- B Parvovirus B19
- C Human herpesvirus 6 (HHV-6) ✓
- D Enterovirus
Correct answer: C. Human herpesvirus 6 (HHV-6)
Explanation
Roseola infantum (exanthem subitum) is caused by HHV-6 (and sometimes HHV-7). It classically presents with 3-5 days of high fever in a 6-24-month-old child, followed by defervescence and appearance of a rose-pink maculopapular rash on the trunk. The child is typically well once the rash appears. Parvovirus B19 causes erythema infectiosum with slapped cheek appearance. Rubella has postauricular lymphadenopathy. Enteroviruses cause varied exanthems.
Reference: Nelson Textbook of Pediatrics, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.