Therapy of Immune Mediated Thrombocytopenia

Abstract

Fifteen dogs with immune mediated thrornbocytopenia (IMT) were studied retrospectively. All dogs had a thrombocyte count below 50,00O/pI when response to therapy was studied. Platelet counts greater than SO,OOO/pI were present in all dogs within 2-9 days of initiating medical therapy. Eight dogs experienced a single episode of thrombocytopenia and seven dogs relapsed over the following 5 to 24 months. Clinical parameters from dogs that experienced a single episode of IMT were compared with data from dogs that relapsed to determine whether any information would identify dogs that were prone to relapse. Signalment, severity of thrombocytopenia, and time to achieve a platelet count above 50,00O/pI were found not to differ (P > 0.05) between these two groups.Five of the seven dogs with relapsing I M T were splenectomized after 2 to 4 episodes (mean, 2.8 k 0.8) of thrombocytopenia over 2 to 14 months. The postoperative progress of these five dogs was followed for 6 to 17 months. Platelet counts were sustained above 200,00O/pI in 4/5 after splenectomy and it was possible to discontinue medical therapy in these dogs. In comparison, the 2 relapsing I M T cases that were not splenectomized continued to require intermittent immunosuppressive therapy.We conclude that signalment and routine pretreatment laboratory test results are not useful in distinguishing dogs with relapsing IMT from those that will experience one episode of IMT. Seemingly, splenectomy is useful in the management of dogs with relapsing IMT. (Journal of Veterinary Internal Medicine 1990; 4:4-7)

Splenectomy as an adjunctive treatment for dogs with immune‐mediated hemolytic anemia: ten cases (2003–2006)

“…Five of the 9 dogs were still on tapered doses of immunosuppressive drugs. This is comparable to prior studies in dogs that utilized a splenectomy for treatment of IMHA, ITP, and Evan's syndrome 11,12 . In one study, 9 dogs afflicted with one of the aforementioned diseases showed a 100% survival rate postoperatively.…”

“…One year postoperatively 5 of 9 dogs in that study were stable without medical treatment; whereas 4 required small dosages of immunosuppressive drugs, which included prednisone (range, 0.5–1.0 mg/kg, q 24 h) and azathioprine (range, 0.5–1.0 mg/kg, q 24 h). Another study described the use of splenectomy for dogs still suffering from ITP 2–14 months after the initiation of medical management 12 . In that study, 5 of 7 dogs with relapsing ITP had splenectomies.…”

“…Four of 5 were in remission without further immunosuppressive therapy 6–17 months postoperatively. The 2 dogs that did not have a splenectomy experienced relapses 12 …”

“…Feldman et al 11 reported survival in 3 of 3 dogs with IMHA, 3 of 3 dogs with immune‐mediated thrombocytopenia (ITP), and 3 of 3 dogs with Evan's syndrome (concurrent IMHA and ITP) following splenectomy. Another study reported on the use of splenectomy for refractory ITP in 5 dogs 12 . The 5 of 7 refractory cases that underwent splenectomy were in remission without further medication 12 .…”

“…Another study reported on the use of splenectomy for refractory ITP in 5 dogs 12 . The 5 of 7 refractory cases that underwent splenectomy were in remission without further medication 12 . These studies suggest that splenectomy may be of benefit in the management of patients with immune‐mediated hematologic disorders.…”