Thrombocytosis in 158 cats (2011-2018)

Leigh A Howard; Andrew D Woolcock; John A Christian; George E Moore

doi:10.1177/1098612X231185680

Thrombocytosis in 158 cats (2011-2018)

J Feline Med Surg. 2023 Jul;25(7):1098612X231185680. doi: 10.1177/1098612X231185680.

Authors

Leigh A Howard¹, Andrew D Woolcock¹, John A Christian², George E Moore³

Affiliations

¹ Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA.
² Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA.
³ Department of Veterinary Administration, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA.

PMID: 37470518
DOI: 10.1177/1098612X231185680

Abstract

Objectives: Thrombocytosis is an uncommon hematologic abnormality that is associated with various physiologic, metabolic, inflammatory and neoplastic conditions in people and dogs. Thrombocytosis is not a well-described abnormality in cats. The objective of this study was to classify thrombocytosis in cats based on underlying disease processes and severity, and to compare this with a control population of cats.

Methods: A retrospective study was conducted by reviewing the medical records of cats with increased (>600 × 10³/µl; thrombocytosis group) and normal (200-600 × 10³/µl; 2:1 age-matched control group) platelet counts between 2011 and 2018. Platelet counts were estimated based on blood smear assessment in all cats. Cats were classified by the severity (mild, moderate or marked) of thrombocytosis. Diagnoses were recorded for all cases, and were classified broadly into either neoplasia, endocrine or inflammatory disease.

Results: In total, 158 cats were identified with thrombocytosis, with 315 cats in the control group. Non-neoplastic inflammatory disease was the most common diagnosis in both groups (54.4% in cats with thrombocytosis and 56.2% in controls; P = 0.77); however, gastrointestinal diseases were more common in cats with thrombocytosis (75.6%) when compared with controls (34.5%; P <0.0001). Neoplasia was diagnosed more frequently in cats with thrombocytosis (44.3%) compared with the control group (25.4%; P <0.0001). Round cell tumor was the most common neoplasia diagnosis in both groups, but gastrointestinal and multicentric lymphoma were diagnosed more frequently in cats with thrombocytosis compared with control cats. No association between the severity of thrombocytosis and etiology was identified.

Conclusions and relevance: Thrombocytosis in cats is more commonly associated with gastrointestinal, hepatobiliary or immune-mediated diseases when compared with a control population. Neoplasia, especially multicentric and gastrointestinal lymphoma, was more commonly diagnosed in cats with thrombocytosis when compared with control cats.

Keywords: Thrombocytosis; gastrointestinal; inflammatory; lymphoma.

MeSH terms

Animals
Cat Diseases* / diagnosis
Cat Diseases* / epidemiology
Cat Diseases* / etiology
Cats
Dog Diseases*
Dogs
Platelet Count / veterinary
Retrospective Studies
Sarcoma* / veterinary
Thrombocytosis* / complications
Thrombocytosis* / epidemiology
Thrombocytosis* / veterinary