Manchester Royal Infirmary, UK
Title: Risk factors for intracranial haemorrhage in autoimmune thrombocytopenia
John Batchelor is currently Consultant in Emergency Medicine at Central Manchester Foundation Trust, England UK. He is also Honorary Lecturer at Manchester Metropolitan University. He undertook his MD thesis at University College London. He has written extensively on the subject of minor head injuries. He was one of the first investigators to identify the risk factors for intracranial bleeding in both adults and children with minor head injury using meta-analysis. His current research interest lies in the area of risk factors for intracranial haemorrhage in both adults and paediatrics secondary to coagulopathy and thrombocytopenia.
The most serious complication of Autoimmune Thrombocytopenia is intracranial haemorrhage. Th e reported incidence of this complication is in the order of 0.5%. Th e most important risk factor for intracranial bleeding is severe thrombocytopenia (platelet count < 10 x 109/L). However this risk factor occurs in 75% or less in the majority of the reported cohort studies. Th e other major risk factor is head trauma which accounts for up to 20% of the cases. Less common risk factors are SLE, AV malformations and viral infections. An important subgroup of cases do not have a clear risk factor such as head trauma and may have a platelet count greater than 10 x 109/L. Cohort studies have shown that in the majority of cases of spontaneous intracranial haemorrhage the bleeding occurs in the cerebral hemispheres and a lesser number in the subdural space. Extradural haematomas are uncommon. Although a mixed picture occurs i.e. intracerebral and subdural the overall pattern is that of a localised bleed rather than a pattern of diff use intracerebral haemorrhages which is oft en seen in acute leukaemia. Th is presentation aims to review and also explore new possible mechanisms by which spontaneous isolated intracranial haemorrhage may occur in patients with thrombocytopenia.