A 30 year old veterinarian presents with nocturnal pain in the right lower back for 2 weeks, in association with fatigability, night sweats, and fever with chills at night.

He migrated from Brazil to the United States 3 weeks ago. He had been working in the same occupation in his home country.

His medical history is unremarkable. There is no history of contact with tuberculosis. He has a single stable sexual partner. There is no family history of spondyloarthropathies.

His ESR is found to be 20 mm/1h. Radiographs of the pelvis are found to be normal. A tuberculin test was performed in view of the symptoms, but is nonreactive.

Prior to migration, he was tested for HIV and found to be negative.

Select Relevant Investigations
MRI Lumbar Spine + B/L SI Joints


There is a widening of the R/s sacroiliac joint, with enhancement of the fluid within. A high diffuse signal intensity is seen in the bone marrow.
The L/s sacroiliac joint appears normal. There is no evidence of erosions or sclerosis.
The lumbar spine appears normal.


C. Trachomatis: negative
N. Gonorrhoeae: negative
Brucella Serology


The standard agglutination test yields a brucella immunoglobulin M (IgM) titre of 1:320
Aspiration of R/s SI joint


Gram stain of the aspirate reveals the presence of numerous gram negative coccobacilli.
Culture results will be available in 3 days.

Select Relevant Management
Streptomycin + Doxycycline
IV Cefotaxime