“The team’s two studies, taken in tandem, strongly suggest that while XMRV does not appear to be directly associated with chronic fatigue syndrome [ME/CFS] in the central nervous system, other substances found in spinal fluid do have an association.”
Steven Schutzer, MD, and colleagues at University of Medicine & Dentistry of New Jersey (UMDNJ) made history in February when they reported finding unique protein signatures in the spinal fluid of both ‘chronic fatigue syndrome’ (ME/CFS) and Lyme patients – suggesting central nervous system involvement in both illnesses.
Now the team reports that their tests of spinal fluid in the same group of 43 ME/CFS patients have turned up no evidence of XMRV (xenotropic murine leukemia-related virus) – and in fact of no common viruses – according to a report published online Apr 5 by the Annals of Neurology.
The team targeted spinal fluid based on the belief that if there is a neurological component to ME/CFS as the symptoms suggest, then spinal fluid might contain a relevant pathogen such as a virus that is associated with the syndrome and, some studies suggest, may be detected in ME/CFS blood.
Spinal fluid is the liquid bathing the central nervous system and thus a “window to the brain,” says Dr. Schutzer. “It is an important area of the body to examine when there is abnormal central nervous system function and an infectious or immunologic cause is suspected.”
The relative separation of the central nervous system from the circulatory system was also an important consideration, he says, because the sheer complexity of blood makes cause and effect far harder to decipher when substances are found there.
Dr. Schutzer and his team analyzed spinal fluid using specialized Polymerase Chain Reaction (PCR) techniques that amplified nucleic acid present in the fluid.
The two studies, taken in tandem, strongly suggest that while XMRV does not appear to be directly associated with CFS in the central nervous system, other substances found in spinal fluid do have an association.
“This latest study was not designed to address the ongoing controversy over possible XMRV in the blood,” said Dr. Schutzer.
“It was specifically designed to survey the central nervous system for XMRV and, if found, other viruses,” he emphasizes. “Here, and in general, the detection of a microbe is only a first step. Additional research would be necessary to prove that it is a cause of a condition.”
The authors urge investigators to search prospectively for microbes and other possible mechanisms of the syndrome, paying particular attention to the central nervous system.
Authors, in addition to Dr. Schutzer, were Megan A. Rounds, David J. Ecker and Mark W. Eshoo of Ibis Biosciences, and Benjamin H. Natelson of UMDNJ, Beth Israel Medical Center and Albert Einstein School of Medicine.
Funding for this study was provided by the National Institutes of Health, through the National Institute of Allergy and Infectious Diseases.
Source: University of Medicine and Dentistry of New Jersey (UMDNJ), news release Apr 5, 2011