Treatment of severe immune-mediated thrombocytopenia with human IV immunoglobulin in 5 dogs.
BACKGROUND
Glucocorticoids with or without other immunotherapy are the initial treatment of choice for dogs with severe immune-mediated thrombocytopenia (IMT). The majority of treated dogs will have improvements in platelet counts within 5 to 7 days of starting therapy, but complications from hemorrhage often occur before a response is seen. Human IV immunoglobulin (hIVIG) blocks Fc receptors on mononuclear phagocytic cells in dogs; it is used in people with idiopathic thrombocytopenic purpura.


OBJECTIVE
The purpose of this study was to describe adverse effects and benefit of hIVIG in addition to conventional immunosuppressive therapy in dogs with severe IMT.


METHODS
Five client-owned dogs with severe primary IMT.


METHODS
Case series. The hospital database was searched for dogs with primary IMT treated with hIVIG.


RESULTS
No adverse effects were noted during or after hIVIG infusion in any treated dog. Over a 6-month follow-up, all dogs were clinically normal when using conventional immunosuppressive therapy. Human IVIG was administered 3 days after initiation of immunosuppressive therapy in 4 dogs, and, after 2 days, in 1 dog. In all dogs, the mean platelet counts pre- and 24 hours post-hIVIG infusion (0.28-0.76 g/kg) were 2,500/pL and 50,600/microL (62,750/microL for the 4 responders), respectively. One dog failed to respond as promptly to hIVIG (0.34 g/kg), and the platelet count increased to 66,000/microL after 9 days of immunosuppressive therapy. The mean duration of hospitalization post-hIVIG in all 5 dogs was 1.8 days (12 hours for responders), and the mean total length of hospitalization was 4.6 days (3.5 days for responders). Active hemorrhage resolved and no packed red blood cell transfusions were required after hIVIG infusion for responders.


CONCLUSIONS
Human IVIG was well tolerated and appeared to be associated with rapid platelet count recovery and amelioration of clinical signs in most dogs with IMT.
Bianco
Domenico
D
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA. bianc037@umn.edu
Armstrong
P Jane
PJ
Washabau
Robert J
RJ
D000818:Animals; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use*; D007155:Immunologic Factors / Q000627:therapeutic use*; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000188:drug therapy / Q000662:veterinary*
D005938:Glucocorticoids; D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors; D007166:Immunosuppressive Agents