Treatment and predictors of outcome in dogs with immune-mediated thrombocytopenia

Objective-To characterize the clinical course of disease and identify prognostic indicators for immune-mediated thrombocytopenia in dogs. Design-Retrospective cohort study. Animals-73 dogs treated for immune-mediated thrombocytopenia at the Foster Hospital for Small Animals at the Tufts Cummings School of Veterinary Medicine and the Tufts Veterinary Emergency Treatment and Specialties Hospital. Procedures-Medical records from the period of January 2002 through June 2008 were reviewed to identify dogs with a diagnosis of immune-mediated thrombocytopenia. Data collected included signalment, clinical signs, results of initial diagnostic tests, treatment, complications, and survival duration. Results-Dog ages ranged from 5 months to 15 years (median, 8.1 years). Cocker Spaniels were overrepresented, compared with their distribution in the entire hospital population during the same period. Sixty-one of the 73 (84%) dogs survived to discharge. Seven (11%) of those dogs were lost to follow-up. Five of the remaining 54 (9%) dogs had a relapse of the disease. The presence of melena or high BUN concentration at admission to the hospital was significantly correlated with a decreased probability of survival. Conclusions and Clinical Relevance-Immune-mediated thrombocytopenia is a serious yet treatable disease, which may have a lower rate of recurrence than previously reported. The presence of melena or high BUN concentration in the study suggested a poor prognosis for affected dogs. (J Am Vet Med Assoc 2011;238:346-352)