Diagnostic usefulness of a lumi-aggregometer adenosine triphosphate release assay for the assessment of platelet function disorders.

Abstract

Platelet dense granule release assays are recommended for diagnosing platelet function disorders and are commonly performed by Lumi-Aggregometer (Chrono-Log, Havertown, PA) assays of adenosine triphosphate (ATP) release. We conducted a prospective cohort study of people tested for ATP release defects to assess bleeding symptoms. Reduced release, with 1 or more agonists, was more common among patients with bleeding disorders than among healthy control subjects (P < .001). The respective likelihood (odds ratio [95% confidence interval]) of a bleeding disorder or an inherited platelet function disorder were high when release was reduced with 1 or more agonists (17 [6-46]; 128 [30-545]), even if aggregation was normal (12 [4-34]; 105 [20-565]). ATP release had high specificity and moderate sensitivity for inherited platelet function disorders, with most abnormalities detected by the combination of 6 μmol/L epinephrine, 5.0 μg/mL collagen, and 1 μmol/L U46619. Platelet ATP release assays are useful for evaluating common bleeding disorders, regardless of aggregation findings.