Page 491 - Problem-Based Feline Medicine

23 – THE BLEEDING CAT 483

● Disseminated intravascular coagulation* (p 501)
Acute and chronic DIC are characterized by variable thrombocytopenia, although clinical bleeding
is uncommon.
● Splenomegaly (p 521)
Splenic sequestration may contribute to thrombocytopenia when there is marked splenomegaly.
INFLAMMATION (INFECTIOUS)
● Feline leukemia virus (FeLV) infection** (p 499)
Bleeding tendencies may be caused by megakaryocytic hypoplasia, immune-mediated platelet
destruction, and DIC secondary to infections and neoplasia. Clinical bleeding is uncommon except
with severe thrombocytopenia.
● Feline immunodeficiency virus (FIV) infection** (p 500)
Bleeding tendencies may be caused by megakaryocytic hypoplasia, prolongation of clotting times
due to unknown mechanisms, and DIC secondary to infections and neoplasia. Clinical bleeding is
uncommon except with severe thrombocytopenia.
INFLAMMATION (IMMUNE)
● Immune-mediated thrombocytopenia (ITP) (p 506)
ITP may be primary or secondary to neoplasia, infectious diseases or drugs. Transient thrombocy-
topenia may occur following vaccination in dogs, but has not been documented in cats. Severe
thrombocytopenia causes spontaneous mucosal bleeding and prolonged bleeding after injury.
IDIOPATHIC
● Miscellaneous diseases (p 505)
Thrombocytopenias due to unknown mechanisms have been seen with a variety of diseases not
typically associated with abnormal bleeding. Clinical bleeding with these abnormalities is uncom-
mon.
TOXIC
● Antibiotics (p 523)
Antibiotics may have various effects on hemostasis including idiosyncratic megakaryocytic
hypoplasia, impaired platelet function, and exacerbating vitamin K deficiency and antagonism.
● Antiplatelet cardiac drugs (p 520)
Aspirin and n-3 fatty acids are given to impair platelet function in an attempt to prevent throm-
boembolism in cardiomyopathy. Effect, if any, is subclinical. Risk for spontaneous bleeding with
newer drugs that block specific platelet receptors is probably low.
● Non-steroidal anti-inflammatory drugs (p 524)
Non-steroidal anti-inflammatory drugs given for analgesia may impair platelet function. Effect on
risk for bleeding is probably minimal.
● Miscellaneous drugs (p 524)
Sedatives, anesthetic agents and anti-histamines may impair platelet function. Effect on risk for
bleeding is probably minimal.

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