Chronic brucellosis of shoulder joint: A case report in Saudi Arabia presenting with chronic shoulder pain

Brucellosis is a zoonotic infection that occurs in various forms. It is caused by an aerobic Gram-negative rod of the genus Brucella . The main sources of infection in humans are the infected domestic animals, mainly cattle, sheep, goats, and dogs. This report describes a case of a 76-year-old female with a history of gastroesophageal reflux and gastric sleeve surgery undergone 5 years back. The patient reported complaining of right shoulder pain for the last 2 months. X-ray demonstrated subchondral cystic changes in the greater tuberosity, thereby suggesting an underlying rotator cuff disease with mild degenerative changes in the acromioclavicular joint. Magnetic resonance imaging revealed severe supraspinatus and infraspinatus tendinosis with rotator cable thickening and significant joint effusion with a moderate amount of fluid in the subacromial-deltoid bursa. The patient exhibited an erythrocytic sedimentation rate and C-reactive protein of 90 mm/h and of 6.6 mg/dL, respectively. Detailed rheumatological tests ruled out rheumatoid arthritis. After 12 months from the initial presentation, the patient has decided to proceed with surgery giving no clinical improvement. She underwent right shoulder arthroscopic synovectomy with subacromial decompression and acromioplasty. Histopathology was consistent with chronic fibrinous inflammation with the absence of granuloma. Acid-fast bacilli stain and Mycobacterium tuberculosis polymerase chain reaction were negative. Gram stain showed Gram-positive cocci, but the culture was negative. The patient did not start any empiric antibiotic before her surgery. She was under observation by the infectious disease team and received 6 weeks of empiric IV vancomycin following her surgery, which resulted in insignificant clinical improvement clinically. The patient had no animal contact. She denied consumption of any raw or unpasteurized milk. However, she mentioned that she consumes Kunafa (a type of sweet commonly consumed in Saudi Arabia) occasionally which might be cooked with unpasteurized cream. Further blood tests with Brucella immunoglobulin G agglutination titer revealed a significant elevation of 1:1280. She was prescribed antibiotics for 6 months before she made a full recovery.