An initial comprehensive study of 24 known cases was conducted by multiple doctors from various disciplines at the Mayo Clinic. They identified the cause of this neurological disease to be occupational exposure to aerosolized pig neural tissue. Investigators from the Minnesota Department of Health simultaneously determined that the 70 ppsi pressure used to liquefy and extract the pig brains caused the aerosolization of the pig neural tissue, sending it into the air in a fine mist. The workers closest in proximity to the "head" table, the area in the plant where high pressured air was used to evacuate the brain tissue from the pig's skull, were the most likely to be affected. The aerosolized mist was inhaled and readily absorbed into the workers' mucus membranes. The pig neural tissue was recognized by their systems as foreign and an immune response was initiated. The pig antigen was found most prominently in the nerve roots of the spine which were also swollen. Researchers determined that the irritation was due to the voltage-gated potassium channels being blocked. They identified 125 1-α-dendrotoxin as the antagonist that binds to and blocks the channels, causing an intracellular build-up of potassium ions which causes inflammation and irritation, and consequently, hyper-excitability in the peripheral nervous system. It is this hyper-excitability that leads to the tingling, numbness, pain, and weakness. Researchers from the Mayo Clinic developed a mouse model that received twice daily liquefied pig neural tissue intranasally to replicate the symptoms that the workers were experiencing. Physiological testing indicated signature antibodies in the mouse model at 100% in potassium channel antibodies and myelin basic antibodies, and 91% in calcium channel antibodies. This model allowed the researchers to decipher what was causing these neurological symptoms. It was found that the potassium channels were being blocked so that inflammation was occurring at the nerve root and causing hyper-excitability down the peripheral nerves.
Progressive inflammatory neuropathy
Chemotherapy-induced peripheral neuropathy
Acute motor axonal neuropathy
Diabetic neuropathy
Small fiber peripheral neuropathy
Vasculitic neuropathy
Alcoholic polyneuropathy
Proximal diabetic neuropathy