The haematological investigation of suspected Non Accidental Injury

Most children suspected of Non Accidental Injury (NAI) will undergo a number of haematological investigations to exclude coagulation defects. Investigations should be dependent on the clinical presentation but often there can be an over or under-requesting of haematological investigations. The correct interpretation of results is reliant on an understanding of both the physiological processes involved in coagulation in children of different ages and of the laboratory testing of the coagulation systems. Age-specific, population-based studies of bruising and bleeding patterns in normal children, NAI children and children with congenital bleeding disorders may be helpful in limiting the number of investigations undertaken for suspected NAI. Investigation of suspected Non Accidental Injury requires a multidisciplinary approach; close liaison between the haematology laboratory and the requesting clinician is integral to this approach. This article describes the use of a staged approach to laboratory investigation.