CHICAGO – New details on the neurological illness that has affected workers at several pork processing plants will be presented at the American Academy of Neurology’s 60th Anniversary Annual Meeting in Chicago, April 12–19, 2008. The information will be presented as part of the Late-Breaking Science program, designed for research of major scientific importance or interest that warrants expedited presentation.
Neurologists have identified the illness as a new disorder which causes symptoms ranging from a transverse myelitis syndrome, inflammation of the spinal cord, in one patient to mild weakness, fatigue, numbness and tingling in arms and legs. Researchers are classifying this condition as an immune polyradiculoneuropathy, (a disease of the peripheral nerves and spinal nerve roots) and it has been referred to as “progressive inflammatory neuropathy.” Details about the initial epidemiology investigation were described in an article in the Morbidity and Mortality Weekly Report on February 8.
The current presentation focuses on the clinical description of patients who worked at a Minnesota pork processing plant. Other cases associated with working at a pork processing plant have been reported in Indiana and Nebraska. All of the Minnesota cases had evidence of nerve involvement, typically affecting the legs and likely caused by an inflammatory process.
Electrodiagnostic tests showed that the patients had damage to the nerves at the root level, adjacent to the spinal cord, and at the farthest reaches of motor nerves, near the connection with muscle. Thirteen out of 15 patients had elevated protein levels in their cerebrospinal (brain and spinal cord) fluid. Most patients had evidence of inflammation on spinal MRI examinations. All had evidence of activation of their immune systems. This was shown by a pattern of specific antibody production that has not been seen before.
“This appears to be a new syndrome of immune-mediated polyradiculoneuropathy, or more simply, a novel neurological disorder caused by an immune system response to something in the workplace environment shared by these individuals,” said study author Daniel Lachance, MD, of the Mayo Clinic in Rochester, MN, and a Fellow member of the American Academy of Neurology.
Lachance said the researchers will present additional details at the AAN Annual Meeting.
The American Academy of Neurology, an association of more than 21,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, epilepsy, multiple sclerosis, Parkinson’s disease, and stroke.
For more information about the American Academy of Neurology, visit www.aan.com.
Editor’s Note: Dr. Lachance will present this research during a scientific platform session at 5:30 p.m. CT/6:30 p.m. ET, on Wednesday, April 16, 2008, in Room 185 AB of the McCormick Place West Convention Center.
Dr. Lachance will be available for media questions during a press briefing at 11:00 a.m. CT/12:00 p.m. ET, on Wednesday, April 16, 2008, in the on-site Press Interview Room, room 182. Dr. Jim Sejvar, a neurologist and epidemiologist from the U.S. Centers for Disease Control and Prevention, will also be available.
If you are a member of the media interested in listening to the press briefing via conference call, please call the AAN Press Room (April 12 – 18) at (312) 791-7053.