This was such a unique case study, we just had to give it an award.
Kristina Simmons Baltutis - NC State
V51 I1 Cases/Abstracts Honorable Mention
Priapism in a Thoroughbred gelding associated with metastatic S. equi infection
K. Simmons, E.A. Coffman, T.M. Beachler, K. McKelvey, B. Breuhaus, C.S. Bailey
Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC
A 12-year-old Thoroughbred gelding presented to the NC State College of Veterinary Medicine for acute priapism and weight loss. A physical exam was unremarkable except for poor body condition (BCS 2/9) and complete protrusion of the erect penis. The penis was reduced into the prepuce following irrigation of the corpus cavernosum with heparinized saline, injection of 10 mg of phenylephrine into the corpus cavernosum, and manual massage using nitrofurazone and DMSO ointment. A purse string suture and penile sling were placed to assist in penile retention and support. The erection recurred approximately 8 hours after the procedure, and treatment was repeated. The purse-string was removed after 48 hours due to superficial trauma. The penis remained moderately erect throughout hospitalization and was treated conservatively with a sling to prevent edema, application of tetracycline wound ointment, and hydrotherapy. Diagnostic procedures to pursue the weight loss included thoracic and abdominal ultrasound, complete blood count and chemistry, urinalysis, urine culture, rectal biopsy, andStreptococcus equi ELISA. Urinalysis revealed 2+ hematuria and pyuria, likely due to preputial inflammation. The serum ELISA assay for S. equi returned strongly positive (1:25,600), consistent with metastatic strangles abscesses. Treatment with trimethoprim sulfamethoxazole (TMS, 30 mg/kg PO BID) and rifampin (5 mg/kg PO BID) was instituted for 8 weeks based on evidence that rifampin may prevent resistance and improve efficacy of the TMS against Streptococcus spp. sequestered in abscesses. At recheck examination seventeen weeks after discharge, the gelding’s BCS was 5/9 and his priapism had improved, although the penis still protruded from the prepuce two inches at most times. Thirty weeks after discharge the animal had returned to a normal weight and the priapism was completely resolved. Priapism is rare is horses, especially geldings, and there are no reports of priapism secondary to metastatic strangles.