Pathogenic substances may be circulating antibodies in the case of immune-mediated diseases or toxins. There are several criteria used to determine feasibility. These include the volume of distribution (low Vd is best), degree of protein binding (higher is better), rate of production of a pathogenic substance. Cytopheresis is also an option to allow reduction of certain cell lines (leukemia, polycythemia vera ) or for collection of specific cell lines.
Immune-mediated diseases including immune-mediated thrombocytopenia (IMT), immune-mediated hemolytic anemia (IMHA), myasthenia gravis (MG), and polyradiculoneuritis have been treated with TPE. By removal of the circulating antibodies, stabilization of the disease course is expected. Most patients will stabilize over the course of 3-4 treatments. Conventional therapy is utilized in conjunction with TPE and currently TPE is utilized in patients that are rapidly progressing or are refractory to conventional therapy. There is interest in its use as a first-line agent but this has not been proven at this time.
It has also been utilized to manage neurologic complications of hyperbilirubinemia. A case report of management of post-attenuation neurologic syndrome (PANS) in a cat has also shown promise for this difficult condition.
Many toxins can be managed in the acute presentation by plasma exchange. Patients ideally should be treated soon after ingestion. Indications for TPE include 1) no known antidote, 2)severity of effects (life-threatening), 3) low Vd, highly protein bound. TPE has been utilized in toxicity due to NSAID, baclofen, vincristine, calcitriol, organophosphate, amanita toxicity. Typically toxicities need only one treatment.
Kopecny L, Palm C, Naylor S, et al. Application of therapeutic plasma exchange in dogs with immune-mediated thrombocytopenia. J Vet Intern Med 2020 34(4):1576–1581.
Vitalo A, Buckley G, Londono L.Therapeutic plasma exchange as adjunct therapy in 3 dogs with myasthenia gravis and myasthenia-like syndrome. J Vet Emerg Crit Care 202131(1):106-111
Hefner GG, Cavanagh A, Nolan B. Successful management of acute bilirubin encephalopathyin a dog with immune-mediated hemolytic anemia using therapeutic plasma exchange. J Vet Emerg Crit Care 2019 29(5):549-557
Tovar T, Deitschel S, Guenther C. The use of therapeutic plasma exchange to reduce serum bilirubin in a dog with kernicterus. J Vet Emerg Crit Care 2017 27(4):458-464
Niemann L, Beckmann K, Iannucci C, et al. Diagnosis of post-attenuation neurological signs syndrome in a cat with refractory status epilepticus and clinical response to therapeutic plasma exchange. JFMA Open Rep 8(2):20551169221121919
At CTAC, we’re committed to providing the highest level of care and support for both you and your dog throughout the SCT process. If you’re ready to take the next step or simply want to learn more about how we can help, our team is here to answer your questions and guide you every step of the way.
