Abstract:
BACKGROUND: Chronic fatigue syndrome (CFS) is a complex, heterogeneous disease characterized by debilitating fatigue that is not improved with bed rest and worsens after physical activity or mental exertion. Despite extensive research into a cause of CFS, no definitive etiology has been determined; however, a large percentage of CFS patients note an acute infectious event that triggers their fatigue.
METHODS: Blood and saliva were collected from 39 CFS cases and 9 healthy control subjects. Peripheral blood mononuclear cells (PBMCs) were tested for human endogenous retrovirus-K18 (HERV-K18) env transcripts using a TaqMan quantitative polymerase chain reaction (qPCR). In addition, viral copy number of human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7) were measured in both saliva and PBMCs using TaqMan qPCRs. Transcript levels and viral copy number were compared to patient CFS symptom severity.
RESULTS: HERV-K18 env transcripts were not significantly different between healthy control subjects and CFS patients. Also, HERV-K18 env transcripts did not correlate with HHV-6 viral copy number or HHV-7 viral copy number in either PBMCs or saliva. HHV-6 viral copy number and HHV-7 viral copy number in both PBMCs and saliva were not significantly different between healthy control subjects and CFS patients. HERV-K18 env transcripts, HHV-6 viral copy number, and HHV-7 viral copy number did not correlate with CFS symptom severity.
CONCLUSIONS: We fail to demonstrate a difference in HERV-K18 env transcripts, HHV-6 viral copy number, and HHV-7 viral copy number between CFS patients and healthy controls. Our data do not support the hypothesis of reactivation of HHV-6 or HHV-7 in CFS.
Source: Oakes B, Hoagland-Henefield M, Komaroff AL, Erickson JL, Huber BT. Human endogenous retrovirus-K18 superantigen expression and human herpesvirus-6 and human herpesvirus-7 viral loads in chronic fatigue patients. Clin Infect Dis. 2013 May;56(10):1394-400. doi: 10.1093/cid/cit086. Epub 2013 Feb 13. http://cid.oxfordjournals.org/content/56/10/1394.long (Full article)