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...