Chronische vermoeidheid het gevolg van hersenschade.*

Het chronisch vermoeidheidssyndroom (CVS) wordt mogelijk veroorzaakt door hersenschade die het gevolg is van hoge koorts bij een virusinfectie. Dat meldden Australische onderzoekers in het tijdschift Journal of Infectious Diseases.
Het zou gaan om het Epstein-Barr-virus, gerelateerd aan de ziekte van Pfeiffer, waarmee zeker driekwart van de bevolking in aanraking is geweest. Niet het virus zelf, maar de hoge koorts die sommige zieken krijgen, zou verantwoordelijk kunnen zijn voor de opkomst van CVS. Sommige patiënten zouden nooit helemaal herstellen van de schade die de koorts aan de hersenen aanricht.
De Australiërs baseren hun bevindingen op een onderzoek onder 39 mensen die een acute koortsaanval hebben gehad na een infectie met het Epstein-Barr-virus. Acht van hen ontwikkelden later het chronisch vermoeidheidssyndroom.
CVS-patiënten zijn onder meer erg moe, slapen slecht en hebben concentratieproblemen. Volgens de onderzoekers spreken hun bevindingen de theorie tegen dat mensen met het syndroom aanstellers zijn en dat hun ziekte psychisch is. „CVS is echt”, aldus professor Andrew Lloyd van de universiteit van New South Wales.

Hit-and-run injury to the brain

A seven-year tracking study has prompted scientists to suggest that chronic fatigue syndrome could be the result of brain injuries inflicted during the early stages of glandular fever*.
Australian researchers have put the suggestion in this week's Journal of Infectious Diseases, which reveals new findings from the 'Dubbo Infection Outcomes Study'. Since 1999, a team led by UNSW Professor Andrew Lloyd have been tracking the long-term health of individuals infected with Epstein-Barr virus (EBV), Ross River virus (RRV) or Q fever infection. Their goal is to discover whether the post-infection fatigue syndrome that may affect up to 100,000 Australians is caused by the persistence of EBV, a weakened immune system, psychological vulnerability, or some combination of these.
Glandular fever - sometimes called 'the kissing disease' - is caused by Epstein-Barr virus (EBV). Transmitted via saliva, its acute symptoms include fever, sore throat, tiredness, and swollen lymph glands. Most patients recover within several weeks but one in ten young people will suffer prolonged symptoms, marked by fatigue. When these symptoms persist in disabling degree for six months or more, the illness may be diagnosed as chronic fatigue syndrome (CFS).
The researchers followed the course of illness among 39 people diagnosed with acute glandular fever. Eight patients developed a 'post-infective fatigue syndrome' lasting six months or longer, while the remaining 31 recovered uneventfully. Detailed studies of the activity of the Epstein-Barr virus in the blood and the immune response against the virus were conducted on blood samples collected from each individual over 12 months.
Commenting on the findings, Professor Lloyd says: "Our findings reveal that neither the virus nor an abnormal immune response explain the post-infective fatigue syndrome. We now suspect it's more like a hit and run injury to the brain.
"We believe that the parts of the brain that control perception of fatigue and pain get damaged during the acute infection phase of glandular fever. If you're still sick several weeks after infection, it seems that the symptoms aren't being driven by the activity of the virus in body, it's happening in the brain."
The research team comprising of scientists from the University of New South Wales, the University of Sydney and the Queensland Institute of Medical Research plan to test their 'brain injury' hypothesis by doing neurological tests on the study participants.
About the Dubbo Infection Outcomes Study
This is a major prospective cohort study following individuals from the time of onset of documented infection with Epstein-Barr virus (the cause of glandular fever), Ross River virus (the mosquito-borne infection which causes rash and joint pain) and Q fever (an infection common in meatworkers and those exposed to livestock).
Funding statement
The Dubbo Infection Outcomes Study is 82 per cent funded by the US Centers for Disease Control. It also receives funding from the National Health and Medical Research Council of Australia.
*Infectious mononucleosis is the North American term for glandular fever
Media contact: Dan Gaffney, UNSW
Tel: (local) 0411 156 015 (international) +61 411 156 015, d.gaffney@unsw.edu.au (Maart 2006)