Infection Is Linked to Sciatica 

Bacterial inflammation could cause pain 

By Edward Edelson

HealthScoutNews Reporter 

THURSDAY, June 21, 2001 (HealthScoutNews) -- A chronic, low-
grade infection 
could be to blame in some cases of sciatica, a British study 
suggests. 

Hidden infections were found in a large percentage of patients with 
the 
persistent pain that originates in the sciatic nerve, the primary 
nerve 
of the leg and the largest nerve in the body. The study was done by a 
group led by Dr. T. S. J. Elliott, professor of microbiology at 
University Hospital in Birmingham, and it appears in the current 
issue of 
the journal The Lancet. 

This is the first suggestion that sciatica could be linked to an 
infection, and it was "basically a chance finding," Elliott says. The 
infectious agent in most of the cases his group studied is a 
bacterium 
associated with acne. It is one that sometimes can cause serious 
infections but is generally regarded as a contaminant rather than an 
important infectious agent, he says. 

"Our hypothesis is that a minor trauma to the spine allows the 
organism 
to enter the body, and that the presence of the organism causes a 
continuing sciatica," Elliott says. Inflammation resulting from the 
infection causes pain, he says. 

Dr. Anne Louise Oaklander, a member of the pain group at 
Massachusetts 
General Hospital, says Elliott's theory is a long shot but worth 
exploring. 

Most cases of sciatica clearly are triggered by abnormal pressure on 
the 
sciatic nerve, usually due to a herniated disc, she says. 

"Pressure on the nerve causes the pain fibers to activate, which 
transmits a message that there is tissue injury in the region the 
nerve 
goes to," says Oaklander, who is also assistant professor of 
anesthesiology, neurology and neuropathology at Harvard Medical 
School. 
"Typically, the patient feels pain down the back of the leg, the lower 
leg or the foot." 

But there are some cases in which imaging tests do not show any 
such 
injury, Oaklander says. If carefully controlled studies show that 
antibiotic treatment can reduce the pain of sciatica, "it would 
suggest 
that infection of herniated discs is one of the things that can 
worsen 
the pain of sciatica," she says. 

Elliott says his group is planning such a study, in which sciatica 
patients will be given antibiotics. ....