Exanthem 6: human herpes virus 6
Human herpes virus 6 (HHV6) is a benign, self-limiting exanthem com-monly infecting children by the age of 2yrs. It is also known as ‘roseola infantum’ and ‘erythema subitum’.
• Prodrome. High-spiking fever up to 41*C lasting for up to 4 days. The fever typically stops once the rash appears.
• Exanthematous phase: the rose-coloured maculopapular rash appears some days later, beginning on the trunk and spreading peripherally. It lasts for 2–5 days.
• Other features: vomiting, diarrhoea, pharyngeal injection without exudates, cervical lymphadenopathy, and febrile convulsions prior to rash (5–10% of cases).
Diagnosis is on clinical grounds. Typical history and there may be associ-ated neutropenia.
Management is supportive: antipyretics for fever.
• The most common complication is febrile convulsion, and HHV6 probably accounts for a third of these in those <1yr of age. Rarely, some children may develop aseptic meningitis, encephalitis, and hepatitis.