Thrombocytopenia

Introduction

• Thrombocytopenia is apparently rare in the cat (incidence 1%) - but may be under-diagnosed.
• It is a clinical sign and NOT a diagnosis - investigation is directed at identifying underlying cause.
• Cause : decreased production or increased utilization of platelets.
• Signs : may be no clinical signs or signs of bleeding.
• Diagnosis : hematology.
• Treatment : depends on cause.
• Prognosis : depends on cause.

Diagnosis

Clinical signs

• Often no clinical signs (spontaneous bleeding often not seen until counts are very low).
• Petechial hemorrhage on mucous membranes or sclera.
• Petechial hemorrhage on skin (may require clipping to see).

• Retinal hemorrhage.

Sequelae

Prognosis

• Guarded since most cases related to significant underlying disease.
• Prognosis in some immune-mediated cases can be favorable if underlying cause if treatable.

Expected response to treatment

• Cessation of spontaneous hemorrhage.
• Increasing platelet count.

Reasons for treatment failure

• Inability to diagnose or treat underlying cause.
• Treatment not sufficiently aggressive.
• Incorrect diagnosis ie thrombocytopenia artifactual.
  • Automated cell counting.
  • Storage in EDTA.

Sources

Publications

Refereed papers

• Tasker S, Cripps PJ & Mackin AJ (2001)Evaluation of methods of platelet counting in the cat.JSAP42, 326-332.
• Tasker S, Mackin A J and Day M J (1999)Primary immune-mediated thrombocytopenia in a cat.JSAP40, 127-131.
• Hodson S & Mackin A (1998)Thrombocytopenia in the cat.Feline Focus8, 2-7.
• Jordan H L, Grindem C B and Breitschwerdt E B (1993)Thrombocytopenia in cats - a retrospective study of 41 cases.JVIM.7, 261-265.
• Boyce J T, Kociba G J, Jacobs R M and Weiser M G (1986)Feline leukemia induced thrombocytopenia and macrothrombocytosis in cats.Vet Pathol23, 16-20.