Evaluation of clinical characteristics, diagnostic test results, and outcome in horses with internal infection caused by Corynebacterium pseudotuberculosis: 30 cases (1995-2003).
OBJECTIVE
To determine clinical signs, results of diagnostic testing, and outcome in horses with internal Corynebacterium pseudotuberculosis infection.


METHODS
Retrospective study.


METHODS
30 horses.


METHODS
Information pertaining to clinical data, results of diagnostic tests, and costs of hospitalization and treatment was extracted from medical records of affected horses.


RESULTS
Internal C. pseudotuberculosis infection was diagnosed on the basis of clinical signs, diagnostic imaging, and clinicopathologic data, including results of serologic tests and bacterial culture. The most common clinical signs were concurrent external abscesses, anorexia, fever, lethargy, weight loss, and signs of respiratory tract disease or abdominal pain. Clinicopathologic abnormalities included a geometric mean reciprocal serum synergistic hemolysin inhibition titer > or = 512, leukocytosis with neutrophilia, hyperglobulinemia, hyperfibrinogenemia, and anemia. Specific organ involvement was diagnosed in 27 of 30 horses. Affected organs included the liver (18 horses), lungs (12), kidneys (7), and spleen (3); multiple organs were affected in 10 horses. Treatment with antimicrobials for a median of 36 days (range, 7 to 97 days) was usually successful, yielding an overall survival rate of 71%.


CONCLUSIONS
Early diagnosis and long-term antimicrobial treatment were important for a successful outcome in horses with internal C. pseudotuberculosis infection. Ultrasonographic imaging was an important technique for identifying specific organs affected, aiding in obtaining samples for a definitive diagnosis, and monitoring response to treatment. Pregnant mares with internal infections are at risk for fetal loss. Preexisting chronic organ disease may be associated with a poor prognosis.
Pratt
Suzanne M
SM
Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907, USA.
Spier
Sharon J
SJ
Carroll
Scott P
SP
Vaughan
Betsy
B
Whitcomb
Mary Beth
MB
Wilson
W David
WD
D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002908:Chronic Disease; D003354:Corynebacterium Infections / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D016925:Corynebacterium pseudotuberculosis / Q000302:isolation & purification; D005260:Female; D006734:Horse Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006736:Horses; D008297:Male; D009928:Organ Specificity; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary; D011379:Prognosis; D012189:Retrospective Studies; D016896:Treatment Outcome; D014463:Ultrasonography
D000900:Anti-Bacterial Agents