Thoroughbred Picadilly Pete undergoes critical emergency care for guttural pouch mycosis

Picadilly Pete, a thoroughbred gelding, known affectionately at home as Dilly, was bred in Pennsylvania and foaled on March 28, 2010.  Sired by Tekken (IRE) out of Truco De Amor, he won over $240,000 during his racing career. 

In early July of this year, Dilly visited the Equine Medical Center for emergency treatment for acute and severe blood loss following epistaxis (nosebleed) early that morning.

When Dilly’s owner Andrea Brownstein of Hillsboro, Virginia, found Dilly hemorrhaging in his stall, she wasn’t sure if he would make it onto the trailer, much less to the hospital. Andrea shared “Vet techs were standing to assist as I pulled into the center, and I felt instant relief”.

When Dilly arrived, he was quiet and dull with visible blood from both of his nostrils, and continued but mild bleeding.  He was clearly dehydrated; his heart rate was elevated and his extremities were cool to the touch. 

Once lightly sedated, a transnasal endoscopy was performed. During the procedure, Maureen Kelleher, clinical assistant professor of sports medicine and surgery was able to evaluate Dilly’s upper respiratory tract and guttural pouches.  Within the left guttural pouch, a large blood clot and fungal plaques were clearly visible.

Epistaxis in horses is primarily caused by a trauma to the head, but in Dilly’s case it was caused by guttural pouch mycosis (GPM), which is a rare, fungal disease of the upper respiratory tract which can often result in fatal hemorrhage. 

Dilly was kept quiet and moved to a nearby stall where stabilization treatments were initiated, including fluid therapy, oxygen supplementation, and antibiotic, antifungal, and anti-inflammatory medications. Dilly’s blood was crossmatched with one of the Center’s blood donors, in case a blood transfusion was needed. The Equine Medical Center maintains a small herd of equine blood donors to provide lifesaving blood for horses like Dilly. There is no substitute for whole blood, which replaces the lost red blood cells and provides protein, clotting factors, and platelets.

Dilly was given 24 hours of stall rest, in the hope of stabilizing his vascular system. An additional endoscopy, after cessation of the hemorrhage, allowed better visualization of the fungal plaques.  The plaques were seen within the medial compartment, along the external surface of the internal carotid artery.  The right guttural pouch thankfully showed no evidence of disease.  Blood was collected from one of the Equine Medical Center blood donors to be on hand in case it was needed during surgery.

Treatment of guttural pouch mycosis requires embolization (forced clotting) of the affected vessel(s).  This delicate procedure requires passing a catheter through the common carotid artery into the internal carotid artery using fluoroscopic guidance.  Once the position of the catheter is confirmed within the internal carotid artery, coils are passed through the catheter and deployed into the artery to cause the artery to thrombose. 

Thrombosis of the artery cuts off the blood supply feeding the fungus resulting in the death of the fungus and resolution of the infection.  Since most horses with this condition are compromised due to blood loss, the procedure is typically performed with the horse standing to avoid general anesthesia in these weakened patients. 

At the Equine Medical Center, Dilly was positioned in the CT room.  He was sedated and local anesthesia was used to anesthetize the region where the surgery to isolate the common carotid artery and place the coil catheter in the artery was performed.  The CT was used for fluoroscopic placement of the arterial catheter.   

Kelleher explains “This procedure is tricky due to the proximity of many important vascular and nervous structures in the head, especially with the horse standing and risk of movement.  Teamwork and communication between the surgery team, anesthesia team, and all of the technical staff allowed the surgery to be completed quickly and efficiently, with little stress on Dilly.”

Dilly’s recovery from surgery was uneventful. He was given 8 liters of whole blood under close monitoring and was slowly weaned off intravenous fluids. Two days after surgery a recheck endoscopy was performed. No continued bleeding was evident in Dilly’s left guttural pouch, which was treated with topical antifungal medication over the fungal plaques.  Just three days after being admitted into the hospital Dilly was ready to return home.

Andrea was thrilled to have Dilly back at home and said “Dr. Kelleher and her team did an amazing job at not only saving Dilly, but their clear communications during his treatment about his status and procedures was reassuring. Dilly is not an easy horse for those he does not know well, and even in his dire state, he gave the team a run for their money.

I was impressed with how kind and patient everyone was with him. I am overjoyed to have my special little Thoroughbred back home – where we refer to him as the horse that didn’t die. I cannot thank you all enough!”

Written by Sharon Peart for the Virginia-Maryland College of Veterinary Medicine.