Fungal osteomyelitis of the axial border of the proximal sesamoid bones in a horse.
METHODS
A 12-year-old Standardbred gelding was referred for swelling of the right metacarpophalangeal joint.


RESULTS
Ultrasonography of the right metacarpal area revealed hypoechoic areas in the right digital sheath and metacarpophalangeal joint consistent with synovial effusion. Radiography of the right metacarpophalangeal joint revealed lysis of the axial border of the proximal sesamoid bones. Aspergillus fumigatus was detected on fungal culture of synovial fluid.


RESULTS
Regional limb perfusion (150 mg of amikacin in 60 mL of saline [0.9% NaCl] solution perfused for 30 minutes) was performed 2 and 4 days after admission. Itraconazole (5 mg/kg [2.27 mg/lb], PO, q 24 h) was administered for approximately 9 weeks. Joint lavage with amikacin (500 mg) in 1 L of saline solution was performed 4 times. Three months after discharge, the owner reported that the horse was mildly lame during trotting but was moving freely and comfortably during all gaits and had gained a considerable amount of weight. Because the osteoarthritis was not expected to improve and because it was recommended that the horse not return to purposeful exercise, the owner decided to retire the horse from racing.


CONCLUSIONS
Various diagnostic imaging methods and fungal cultures are useful for diagnosing fungal osteomyelitis of the axial borders of the proximal sesamoid bones in horses. Fungal osteomyelitis of the sesamoid bones and erosive arthritis should be considered as a differential diagnosis for horses in which corticosteroids have been administered intra-articularly.
Sherman
Kevin M
KM
Myhre Equine Clinic, 100 Ten Rod Rd, PO Box 1673, Rochester, NH 03866, USA.
Myhre
Grant D
GD
Heymann
Elizabeth I
EI
D000818:Animals; D000935:Antifungal Agents / Q000627:therapeutic use*; D001228:Aspergillosis / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D001232:Aspergillus fumigatus / Q000302:isolation & purification*; D006734:Horse Diseases / Q000175:diagnosis* / Q000188:drug therapy; D006736:Horses; D007794:Lameness, Animal / Q000175:diagnosis / Q000188:drug therapy / Q000382:microbiology; D008297:Male; D010019:Osteomyelitis / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D011859:Radiography; D012716:Sesamoid Bones / Q000000981:diagnostic imaging / Q000382:microbiology*; D016896:Treatment Outcome
D000935:Antifungal Agents