A 10-year-old 8.8-kg (19.4-lb) castrated male West Highland White Terrier (vaccination status, current) was evaluated because of acute progressive tetraparesis. The dog had been initially examined by the referring veterinarian because of intermittently frantic scratching at its face over a 2-day period. Forty-eight hours after examination by the referring veterinarian, acute paraparesis and hyperreflexive patellar reflexes were evident. Twelve hours later, spinal reflexes were absent in the pelvic limbs and decreased in the right thoracic limb. Deep pain sensation was intact in all 4 limbs, and there was full range of motion in the head and neck. At 72 hours after the initial examination, the dog was reportedly tetraparetic. The referring veterinarian administered carprofena (4.5 mg/kg [2.0 mg/lb], SC), 2 doses of buprenorphine hydrochloride (0.02 mg/kg [0.009 mg/lb], IV) 6 hours apart, and doxycycline (5.6 mg/kg [2.5 mg/lb], IV). Prior to this episode, the dog was not receiving any medications. The dog was then referred for further evaluation.
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The authors thank Dr. Araceli Lucio-Forster for confirmation of the tick species.
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