Effect of preanalytical and analytical variables on the clinical utility of mean platelet volume

BACKGROUND: The study endpoint was to analyze the effect of preanalytical (time, temperature, anticoagulant) and analytical (imprecision, correlation between volume and platelet concentration) variables on mean platelet volume (MPV). A further aim was to calculate in an adult population the reference intervals using the Sysmex XE-5000 analyzer. A critical evaluation was also made of the clinical utility of these parameters. METHODS: Analyses of the above values were performed in duplicate in 170 healthy adults of both sexes: (1) within 30 min from collection, and (2) after 4 h. To evaluate stability over time, the value of the platelet parameters of 20 subjects were determined, a re-analysis being performed for a period of up to 24 h on samples maintained at room temperature and 4°C using either K2-EDTA or Na-citrate as anticoagulants. RESULTS: The stability over time of MPV closely depends on the anticoagulant used, storage temperature and time interval between venipuncture and analysis. An inverse, non-linear correlation between MPV and platelet count was also found. CONCLUSIONS: In view of their effect on MPV and other related indices, the preanalytical and analytical variables make them, little more than experimental.