Infectious Sacroiliitis in Conjunction with Brucella canis in a Dog

Introduction: Brucellosis is a zoonotic pathogen which causes reproductive failure and osteoarticular abnormalities in dogs and people. Reviews of brucellosis in humans have shown that sacroiliitis was more prevalent than discospondylitis. Comparatively, Brucella canis sacroiliitis has not been reported in dogs.

Clinical Findings: A 1.5-year-old, neutered male Labrador retriever with a 1-month history of pelvic limb lameness was referred to our orthopedic service for evaluation. Examination revealed a bilaterally stilted pelvic limb gait with a grade 1/5 left pelvic limb lameness. Pain was elicited during palpation of the lumbar epaxial musculature and extension of the hip joints.

Diagnostics: Orthogonal radiographic views of the spine and pelvis revealed areas of lucency within multiple vertebral endplates and the sacroiliac joints. A computed tomography scan revealed multiple sclerotic lesions in the vertebral endplates and widening of the sacroiliac articulations with subchondral sclerosis. A brucellosis titer was performed, and positive result confirmed by agar gel immunodiffusion (AGID) test.

Discussion: Brucellosis is known to cause discospondylitis in dogs but has never been reported in the sacroiliac joint. Human patients with brucellosis-related discospondylitis and sacroiliitis exhibit pelvic limb lameness and spinal pain. Based on the findings in this case, we suggest that sacroiliitis be included as a differential diagnosis for pelvic limb lameness in dogs with B. canis discospondylitis.

Acknowledgment: There was no proprietary interest or funding for this project.