Human Herpesvirus 6 Infection Differential Diagnoses

Updated: Nov 10, 2015
  • Author: Michelle R Salvaggio, MD, FACP; Chief Editor: Burke A Cunha, MD  more...
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Diagnostic Considerations

In infants with signs and symptoms of classic roseola infantum, human herpesvirus 6 (HHV-6) is the causative agent. However, other causes for fever and rash should be excluded. Misdiagnosis of a condition more serious than roseola is a pitfall. Many differential diagnoses exist that can present with a rash and a fever.

In immunocompetent adults with symptomatic HHV-6 disease, the illness closely resembles mononucleosis. Infection with Epstein-Barr virus (EBV) or cytomegalovirus (CMV) should be excluded.

Recognizing HHV-6 infection in patients who are immunocompromised, especially patients with AIDS and recipients of organ transplants, is important. In immunocompromised patients with symptomatic HHV-6 disease, CMV infection is often present and must be diagnosed and managed.

Illnesses associated with HHV-6 (eg, encephalitis and pneumonitis) present as reactivated HHV-6 infection. Reactivation of HHV-6 in patients with AIDS can be serious, with fever, meningeal compromise, seizures, and encephalitis possible developments. [42]

In addition to the conditions in the differential diagnosis, other problems to be considered include the following:

HHV-6 is among the factors implicated in the severity of drug reaction with eosinophilia and systemic symptoms (DRESS), or drug-induced hypersensitivity syndrome (DIHS). [44, 45] Early demonstration of HHV-6 reactivation may represent a prognostic factor for identifying patients at higher risk for severe DRESS.

HHV-6 transcripts were found in carbamazepine-induced hypersensitivity syndrome by in-situ hybridization in 1 patient. [46] HHV-8 reactivation has also been linked with DRESS caused by other medications, including lamotrigine. [47] Another report linked carbamazepine with DRESS. [48] Additionally, a study cited trichloroethylene exposure in DRESS. [49]

Differential Diagnoses