haematology - bleeding disorders Flashcards
approaches to bleeding disorders
- bleeding patient
- can have normal initial labs - abnormal bleeding tests
- little clinical sig without Hx of bleeding
broad classification of bleeding disorders
congenital
acquired
vascular defects
platelet disorders
coagulation disorders
features of vascular defects
superficial bleeding into skin and mucosal membranes
bleeding immediately after injury
features of platelet disorders
superficial bleeding into skin and mucosal membranes
bleeding immediately after injury
features of coagulation disorders
bleeding into deep tissues, muscles, and joints
delayed but severe bleeding after injury
prolonged bleeding
examples of congenital vascular defects
Osler-Weber-Rendu syndrome
connective tissue disease, eg. EDS
examples of acquired vascular defects
senile purpura
steroids
scurvy (perifollicular haemorrhages)
infection (eg. meningococcal measles, dengue)
platelet disorder classification
decreased function
- acquired
- congenital
decreased number
- decreased production
- increased destruction
causes of acquired decreased platelet function
aspirin
cardiopulmonary bypass
uraemia
causes of congenital decreased platelet function
storage pool disease
thrombasthenia (glycoprotein deficiency)
causes of thrombocytopenic platelet disorders with decreased production
bone marrow failure
causes of thrombocytopenic platelet disorders with increased destruction
autoimmune thrombocytopenia purpura (AITP) drugs, eg. heparin DIC HUS TTP
peak age of acute ITP vs chronic ITP
acute: 2-6 years
chronic: adults
F:M of acute ITP vs chronic ITP
acute: 1:1
chronic: 3:1
preceding infection in acute ITP vs chronic ITP
acute: common
chronic: rare
onset of symptoms of acute ITP vs chronic ITP
acute: abrupt
chronic: abrupt - indolent
platelet count at presentation in acute ITP vs chronic ITP
acute: <20,000
chronic: <50,000
duration of acute ITP vs chronic ITP
acute: 2-6 weeks
chronic: long term (associated with autoimmune disease, CLL, HIV)
spontaneous remission of acute ITP vs chronic ITP
acute: common, self limiting
chronic: uncommon
treatment of chronic ITP
IVIg
steroids
splenectomy
examples of inherited coagulation disorders
haemophilia A
haemophilia B
Von Willebrand’s Disease
haemophilia A
factor VIII deficiency
inheritance pattern of haemophilia A
X linked recessive
rarely acquired
presentation of haemophilia A
often early in life or prolonged bleeding after surgery/trauma
dx of haemophilia A
↑ APTT
normal PT
↓ factor VIII assay