Friday, 17 September 2010

MRCP revision battle 14.4: Thrombocytopenia

Thrombocytopenia refers to low numbers of platelets.
Generally the lower limit of normal for platelets is 150 000, with thrombocytopenia often defined as <50 000.

Low platelets increase the risk of bleeding/bruising, commonly manifesting as bleeding gums or nose bleeds.

Causes of thrombocytopenia can be broadly divided into causes that increase platelet destruction and causes that decrease production:
  1. increased platelet destruction (= DISC HH)
    • DIC
    • ITP
    • SLE
    • CLL
    • Heparin
    • Hypersplenism (portal hypertension, leukaemia)
  2. decreased platelet production (=CAB M)
    • Chemo/radiotherapy
    • aplastic anaemia
    • B12/folate deficiency
    • marrow infiltration
Isotretinoin and valproic acid have also been associated with thrombocytopenia.

Treatment is dependent on the cause/the symptoms.

Onwards to the last haematological battle of the day, ITP...