Roseola Infantum

Aka: Roseola Infantum, Roseola, Sixth Viral Exanthem of Childhood, Exanthem Subitum, Human Herpes Virus 6, HH6

1. Etiology
   1. Human Herpes Virus Type 6
   2. Human Herpes Virus (Herpesviridae)
2. Epidemiology
   1. Peak ages: 6-18 months
   2. Very common
      1. Prevalence of Antibody to HHV-6 approaches 100% by 3 years of age
3. Signs
   1. Days 1-2
      1. Anorexia
      2. Vomiting
      3. Occipital Lymphadenopathy
   2. Days 2-3
      1. High Fever starts (103 to 106 F)
         1. Occurs at onset without accompanying localizing signs
         2. Fever Without Focus
            1. Often a diagnostic dilemma until the rash appears
            2. Child appears well without focal findings
            3. Mild cough or Rhinorrhea may be present
            4. Mild Diarrhea may be present
   3. Day 4
      1. Rash onset as fever abates
         1. Fine, erythematous or pink Macules and Papules (maculopapular rash)
         2. Pink, blanchable, almond shaped Macules
         3. Most common centrally on the trunk and neck (may spread peripherally to extremities)
         4. Macules become confluent with one another and then fade within hours to 2 days
      2. Other associated findings
         1. Viral Sialoadenitis (especially Parotid Gland)
4. Differential Diagnosis
   1. See Fever Without Focus
   2. Rubeola (Measles)
      1. Rash in Measles starts on face (especially behind ears) and spreads inferiorly
      2. Children with Measles appear ill (contrast with normal appearance in Roseola)
5. Complications
   1. Febrile Seizures (common cause)
6. Management
   1. Symptomatic
   2. Tylenol or Ibuprofen for fever
7. References
   1. Latessa (2012) AAFP Board Review Express, San Jose
   2. Allmon (2015) Am Fam Physician 92(3): 211-6 [PubMed]