Meet Wasabi, a 7-year-old mixed breed dog who is battling progressive generalized myasthenia gravis (MG), an immune mediated disease where the body attacks itself, disrupting communication between the nerve and muscle! For Wasabi, this meant a change in his voice and muscle weakness preventing him from enjoying his travels. Eventually, Wasabi also became unable to swallow his food due to a paralyzed esophagus, putting him at risk for a potentially fatal complication of aspiration pneumonia.
Wasabi struggled with standard medical management, experiencing rare complications which required a visit to the ER. That experience sent his parents searching for another therapeutic option. A search online led Wasabi’s family to investigate Therapeutic Plasma Exchange (TPE), and before long, they were put in contact with the Nephrology & Extracorporeal Therapy (ECT) Team at CASE. After a phone consult, Wasabi’s family made the 10 hour drive and booked a vacation rental for the week in Boulder, Colorado.
Dogs with both generalized and focal non-thymoma-associated MG can experience spontaneous immune remission resulting in a complete recovery. However, historic mortality rates have been as high as 60%! That said, if we could reverse Wasabi’s signs with TPE treatment and refined medical management, we were hopeful we could improve Wasabi’s chances to see a spontaneous immune remission!
Therapeutic plasma exchange (TPE) typically takes 2-3 hours and is performed over the span of about 1 week. Wasabi was treated with a membrane-based technique where his blood is continuously pumped through a filter, and the plasma is separated from the cellular component of blood. Wasabi’s plasma contained immunoglobulins that were responsible for interrupting the conversation between the nerves and muscles. This “bad” plasma is discarded, while the new plasma from a healthy blood donor dog is mixed with the cellular component of the blood and returned to Wasabi.
Wasabi underwent 3-TPE treatments, requiring plasma from about 10 blood donors. With this new “good” plasma, we saw improvements each day! First, Wasabi was able to walk double the distance he could before without collapsing. Then, his voice returned. Last but certainly not least, Wasabi’s ability to eat improved! Not all pets’ megaesophagus resolve with treatment, but Wasabi was one of the lucky ones! After the week of treatments, Wasabi was discharged on a new medial regimen to slow the accumulation of bad immunoglobulins in the blood before his disease spontaneously resolved.
Wasabi has been doing much better at home. We have teamed up with Wasabi’s home veterinarian to wean the medications in hopes that we see spontaneous resolution of the MG!