If you search the literature you will quickly realize that polyneuritis equi (PNE) has a grim prognosis. The prognosis is poor because there are no recognized treatments. Only palliative care and euthanasia are offered as the standard of care for the PNE horse. It is our goal to change that with our Hope Initiative.
We began to recognize a pattern in horses with neuromuscular disease and a literature search led us to papers published in the 1980’s. One paper authored by Fordyce gave specific signs used to evaluate horses with putative PNE and led to the Fordyce Score. We found quite a bit of research done in horses relating to PNE. The disease is rare and presents clinically with diffuse involvement of extradural nerve roots of multiple peripheral nerves. The pathology is a polyneuropathy characterized by inflammation and demyelination. PNE has no known single cause. The inflammatory process may initiate primary or secondary demyelination of nerves by a “bystander mechanism” where any antigen that reaches the peripheral nervous system attracts and activates lymphocytes and macrophages. We’ve reviewed the topic for you in our eBook Polyneuritis explained, available on Amazon for $4.99. The disease may be reversed if it is caught early and remyelination of the nerves can restore function.
A spectrum of signs can be recognized in PNE-horses and careful case analysis gave us the heads-up that treatment may be initiated before chronic demyelination progressed to end-stage disease. That’s when we knew that a horse can recover from PNE. We were surprised to find that the literature described a diagnostic test for myelin protein antibodies many years ago. The presence of these antibodies were related to disease. The molecular structure of myelin was determined and the immune-mediated process was determined experimentally in animals. Some tweaks in the diagnostic protocol were needed, using a recombinant protein avoided non-specificity issues and folding the protein into its native state was necessary to make the test useful. Finally, epitope mapping was highly illuminating to understand the pathogenesis of disease.
We’re developing a licensed treatment. Our next step is a field effectiveness study. A (any breed) horse that is between 2 and 30 years old , 605-2420 pounds and shows signs of PNE with a Fordyce score of 4 is considered eligible. There are some other restrictions, and qualification to receive medication is made on a case-by-case basis. Some testing is required, horses need to be negative for sarcocystosis by serum analysis and the possibility of trauma is ruled out by examination, history, or radiography. Your veterinarian can use endoscopic exam or radiographs to rule out osteoarthropathy. Vaccinations must be current (within a year) and include rabies, EEE, WEE, and WNV. Of course, before starting any medications a serum chemistry and CBC should be done.
Some of the other qualifications are: the horse is expected to be manageable and cooperative with handling, examinations, and the owner is able to give medications daily. The study involves a two week treatment and two clinical examinations made by your veterinarian. The owner will need to fill out a checklist each day the horse receives the medication and this checklist is how we evaluate the response to treatment. If you are unsure that your horse qualifies based on the clinical signs you are seeing, you can email us or use the following links, answer some questions, and we’ll get back to you. https://forms.gle/cjTLUwMt4fqhovo77
You may already know, based on your experience, that your horse shows signs of PNE, or your veterinarian has made the diagnosis. This link is useful to determine the Fordyce score and eligibility for the study: https://forms.gle/jcuTjM4RoQUEip6q7