Abstract
In patients with normal plasmatic coagulation and bleeding tendency, platelet function
defect can be assumed. Congenital platelet function defects are rare. Much more commonly
they are acquired. The clinical bleeding tendency of platelet function defects is
heterogeneous, which makes diagnostic approaches difficult. During the years, a large
variety of tests for morphological phenotyping and functional analysis have been developed.
The diagnosis of platelet function defects is based on standardized bleeding assessment
tools followed by a profound morphological evaluation of the platelets. Platelet function
assays like light transmission aggregation, luminoaggregometry, and impedance aggregometry
followed by flow cytometry are commonly used to establish the diagnosis in these patients.
Nevertheless, despite great efforts, standardization of these tests is poor and in
most cases, quality control is lacking. In addition, these tests are still limited
to specialized laboratories. This review summarizes the approaches to morphologic
phenotyping and platelet testing in patients with suspected platelet dysfunction,
beginning with a standardized bleeding score and ending with flow cytometry testing.
The diagnosis of a functional defect requires a good collaboration between the laboratory
and the clinician.
Keywords
platelet function defect - light transmission aggregometry - inherited platelet disorder
- granule defect
