Related Experiment Video
Updated: Aug 17, 2026

Intradermal Inoculation of Mycobacterium avium in the Mouse Ear
Published on: July 3, 2025
Septic arthritis and granulomatous synovitis caused by infection with Mycobacterium avium complex in a horse
Christina A Hewes1, Robert K Schneider, Timothy V Baszler
1Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA.
Abstract:
A 12-year-old American Saddlebred gelding was referred to a veterinary teaching hospital for evaluation of a chronic lameness problem in the right radiocarpal joint. The horse had been treated for osteoarthritis of the right radiocarpal joint with multiple injections of cortisone during the past 3 years. The horse was severely lame on the right forelimb at a trot. Radiography and computed tomography revealed a 3 x 2-cm lytic defect in the distal portion of the radius and periarticular bone proliferation around the right radiocarpal joint. Ultrasonography of the distal portion of the radius revealed a soft tissue mass in the palmarolateral aspect of the joint. Proliferative synovium with a large amount of fibrin was observed in the dorsal and palmar aspects of the joint via arthroscopic examination of the right radiocarpal joint. Histologic examination of synovial biopsy specimens revealed proliferative granulomatous synovitis with giant cells. Mycobacterium avium complex was cultured from the synovial fluid. Infection with M avium complex should be considered in horses with chronic recurring arthritis associated with granulomatous synovitis.
Related Concept Videos
Tuberculosis
Cryptococcal Meningitis
Atypical Pneumonia
Pulmonary Tuberculosis IV
Several diagnostic approaches are used to detect TB. The conventional method is the Tuberculin Skin Test (TST), also known as the Mantoux test. However, this method has...
Pulmonary Tuberculosis III
The first classification is based on the development of the disease, and it includes the following categories:
Bacterial Meningitis II: Pathophysiology