Significance of platelet function diagnostics for clarification of suspected battered child syndrome.

The manifestation of an unclear bleeding tendency in childhood calls for an extended coagulation work-up, particularly when a battered child syndrome is suspected and typical concomitant injuries are absent. The chosen diagnostic tests should be able to detect the presence of relatively common coagulation defects such as von Willebrand syndrome or hemophilia, but also rare diseases such as inherited thrombocytopathies. The PFA-100® test does not help to provide a definite diagnosis especially in cases of mild inherited thrombocytopathies, since in most cases the PFA-100® test results are normal. For this purpose, specific platelet function testing is needed. However, the methods are only available in some coagulation laboratories. Also, other limitations need to be taken into consideration such as pre-analytical problems and difficulties in the interpretation of test results especially in infants. We present two cases that were diagnosed with an aspirin-like defect as an inherited thrombocytopathy, even though their PFA-100 closure times were within the normal range. Based on pathological findings in the platelet aggregometry test, this diagnosis could be made.

Factor XIII deficiency mistaken for battered child syndrome: case of "correct" test ordering negated by a commonly accepted qualitative test with limited negative predictive value.

We report herein a case of Factor XIII deficiency that remained undiagnosed until 2 years of age. Part of the delay in diagnosis was a consequence of testing that was performed on a blood sample obtained after plasma transfusion therapy for a life-threatening bleeding episode. Due to insufficient family follow-up after discharge from the hospital, the diagnosis was delayed 1 year until the child was rehospitalized and a pre-transfusion plasma sample was tested. The commonly accepted approach of using only a qualitative test for the diagnosis of factor XIII deficiency is challenged by this case report.