Underlying diseases and clinicopathologic variables of thrombocytopenic dogs with and without platelet-bound antibodies detected by use of a flow cytometric assay: 83 cases (2004-2006).
OBJECTIVE
To characterize underlying diseases and clinical and clinicopathologic variables of thrombocytopenic dogs with and without platelet-bound antibodies (PBAs) and to evaluate clinicopathologic variables of dogs with primary immune-mediated thrombocytopenia (IMT).


METHODS
Retrospective case series.


METHODS
83 thrombocytopenic dogs.


METHODS
Medical records were reviewed to identify dogs in which PBA tests were performed between 2004 and 2006; PBAs were measured via flow cytometry.


RESULTS
PBAs were detected in 37 of 83 (45%) dogs. Thirteen dogs were suspected of having primary IMT. Median platelet counts were significantly lower in dogs with PBAs, compared with counts in dogs without PBAs. Dogs suspected of having primary IMT had significantly lower median platelet counts, compared with counts for those with secondary IMT. Mean platelet volume (MPV) was increased (> 14.3 fL) significantly more often in dogs without PBAs (19/33 [58%]) than in dogs with PBAs (7/26 [27%]). No dogs suspected of having primary IMT had an increase in MPV. Examination of bone marrow aspirates revealed an increase in megakaryopoiesis in a higher percentage of dogs with PBAs (14/21 [67%]) than in dogs without PBAs (7/18 [39%]). An increase in megakaryopoiesis was detected in all dogs suspected of having primary IMT that had a bone marrow analysis.


CONCLUSIONS
Platelet counts, results of bone marrow analysis, and MPV may be helpful in dogs for the differentiation between primary IMT and thrombocytopenia resulting from other diseases. An MPV within or less than the reference range did not rule out an increase in megakaryopoietic activity.
Dircks
Brigitte Hedwig
BH
Small Animal Clinic, University of Veterinary Medicine Hannover, 30173 Hannover, Germany.
Schuberth
Hans-Joachim
HJ
Mischke
Reinhard
R
D000818:Animals; D000906:Antibodies / Q000378:metabolism*; D001792:Blood Platelets / Q000378:metabolism*; D004283:Dog Diseases / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*; D004285:Dogs; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary*; D007249:Inflammation / Q000150:complications / Q000662:veterinary; D008297:Male; D009369:Neoplasms / Q000150:complications / Q000662:veterinary; D010273:Parasitic Diseases, Animal / Q000150:complications; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D012189:Retrospective Studies
D000906:Antibodies