Given all the interest in infections here's another study from Ectrims 2006 that I'm also surprised no one has posted.
PCR for bacteria in multiple sclerosis cerebrospinal fluid
J.W. Lindsey, S. Patel (Houston, USA)
Objective: The objective of this study was to use a sensitive PCR method to test for the presence of seven different groups of bacteria in the cerebrospinal fluid (CSF) of multiple sclerosis patients.
Background: The etiology of multiple sclerosis is currently unknown, but many features of the disease suggest an infectious cause. The clinical course, the inflammatory infiltrates seen on histology, and the oligoclonal bands in the cerebrospinal fluid are all consistent with a recurrent or persistent infection. Similar diseases, such as acute transverse myelitis, acute disseminated encephalomyelitis, and Guillain-Barre syndrome, are linked to infections. And chronic infection with Treponema or Borrelia can cause neurologic disease.
Methods: We designed nested sets of PCR primers specific for the 16S ribosomal DNA of spirochetes, campylobacter, mycoplasma, chlamydia, bartonella, mycobacteria, and streptococcus. Each set of primers is designed to amplify DNA from all members of the desired group without amplifying DNA from common laboratory contaminants. We extracted DNA from the CSF of 10 patients with relapsing-remitting MS, 10 patients with primary progressive MS, and 9 controls. We amplified the DNA with nested PCR, and visualized the PCR products on agarose gels. Each experiment included both MS patients, controls, and a saline negative control. We defined the sensitivity of our method using serial dilutions of known amounts of bacterial DNA.
Results: The majority of the CSF specimens were negative for bacteria with all sets of primers. Three MS specimens and one control had a faint band of the correct size with the spirochete primers. Sequencing identified this PCR product as coming from a propionibacterium rather than a spirochete. Further experiments with primers specific for that sequence demonstrated that it was present at low concentrations in all specimens and is likely a laboratory contaminant. The sensitivity of the method was excellent. We could detect 10 copies or less of bacterial DNA per PCR reaction. This corresponds to a concentration of 200 bacteria per ml of CSF.
Conclusions: Using a very sensitive PCR method, we were unable to find evidence for the presence of any of the seven tested groups of bacteria in the CSF of MS patients.
This study supported in part by the National Multiple Sclerosis Society
Now, I thoroughly expect some will readily dismiss the study, particularly as it might pertain to the controversies surrounding cpn, difficulties culturing it, and the discrepancies among labs. I do know (surprise) that some labs seem to find cpn while others don't. This one apparently didn't find evidence of cpn or of the other bacteria that were tested.
I'm thankful that there's continued research in this area. And, the beat goes on......as does the controversy I'm sure.