Effect of plasma transfusion on serum amyloid A concentration in healthy neonatal foals and foals with failure of transfer of passive immunity

Abstract Background Anecdotal evidence suggests plasma transfusions increase serum amyloid A (SAA) concentrations in healthy neonatal foals making this marker of inflammation inappropriate for therapeutic decision making in such animals. Hypothesis/Objectives Administration of hyperimmune fresh frozen plasma (FFP) increases SAA concentration in healthy foals and in foals with failure of transfer of passive immunity (FTPI). Animals Eighty‐six healthy foals. Methods Prospective cohort study. Foals 8 g/L; n = 33) were enrolled. A healthy nontransfused group of foals (IgG >8 g/L; n = 21) also was included. Serum amyloid A concentration was determined before (t0h) and after (t24h) administration of FFP. Changes in blood SAA concentration were assessed using linear regression models. Results No statistical differences were found in SAA concentration at t0h or t24h among the 3 groups (P > .05, for all comparisons). The variation in SAA concentration before (t0h) and after (t24h) plasma transfusion showed that administration of FFP was not associated with the changes in SAA concentration (P > .05). An association between SAA concentration at t0h and at 24 hours (P < .05) was identified, where foals with higher SAA concentration at t0h also had higher SAA concentration at t24h. Conclusions and Clinical Importance Administration of FFP to newborn foals was not associated with changes in SAA concentration

Rapid clinical progression of B-cell chronic lymphocytic leukemia in a horse

Abstract CASE DESCRIPTION A 17-year-old Friesian gelding was examined at a referral hospital because of a 1-month history of mild exercise intolerance and marked lymphocytosis. CLINICAL FINDINGS Physical examination revealed no peripheral lymphadenopathy or other abnormalities. Results of an abdominal palpation examination per rectum and thoracic and abdominal ultrasonographic examinations were unremarkable. B-cell chronic lymphocytic leukemia (CLL) was diagnosed on the basis of severe lymphocytosis and positive expression of the B-cell marker CD20 by lymphocytes in the bone marrow and peripheral blood. TREATMENT AND OUTCOME Treatment with prednisolone (2 mg/kg [0.9 mg/lb], PO, every other day) and chlorambucil (20 mg/m2, PO, every 3 weeks for 2 doses, then every 2 weeks) was initially associated with improvement in clinical signs and a decrease in the lymphocyte count. However, 3 weeks after administration of the first dose of chlorambucil, the lymphocyte count began to increase. One week later, the horse developed episodes of recurrent fever and the lymphocyte count continued to increase. Despite continued administration of the prednisolone-chlorambucil protocol, the horse's clinical condition deteriorated rapidly, and it was euthanized 6 weeks after initial examination at the referral hospital because of a poor prognosis. A necropsy was not performed. CLINICAL RELEVANCE B-cell CLL has been infrequently described in horses. This report was the first to describe the use of chemotherapy, albeit unsuccessful, for the treatment of B-cell CLL in a horse. This information should be useful for guiding expectations for prognosis and management of other horses affected with the disease. </jats:sec