Testing for heritable thrombophilia in children at Starship Children's Hospital: an audit of requests between 2004 and 2009.

AIMS

The aim of this study was to review patterns of requests for heritable thrombophilia and to audit these findings against an international standard.

METHODS

Review of requests for antithrombin, protein C, protein S, activated protein C resistance, Factor V Leiden and prothrombin G20210A mutation analysis in children <16 years between 1/1/2004 and 31/12/2009. Data for patient characteristics, test results, origin of request, requesting department and indication were obtained. The 2010 British Committee for Standards in Haematology (BCSH) clinical guidelines for testing for heritable thrombophilia was used as the standard for the audit.

RESULTS

On 269 patients, 379 requests were made. Thirty-four per cent of tests were abnormal but only 36% of abnormal tests were repeated. Seven per cent of patients were confirmed with a heritable thrombophilia. Thirty-four tests were performed on patients on anticoagulation. The median age was 6.903 years. Fifty-three per cent of requests came from a ward, 28% from outpatients, 14% from an intensive care department and 5% from the emergency department. Departments most frequently requesting tests were neurology (20%), paediatric intensive care (15%) and cardiology (12%). Indications for testing were arterial thrombosis (5%), cerebral vein thrombosis (4%), deep vein thrombosis (12%), stroke (23%), asymptomatic relative (6%), intra-abdominal vein thrombosis (8%), start oestrogen containing medication (2%), purpura fulminans (0.2%), heparin resistance (8%) and other (35%).

DISCUSSION

The large majority of requests did not satisfy the BCSH criteria. Requesting behaviours are haphazard. Better appreciation of the difficulties of interpreting results in children of different ages and in different clinical settings amongst paediatricians is required.