Platelet distribution width for differential diagnosis of thrombocytosis

Abstract

Differential diagnosis of thrombocytosis is not always obvious. The routine clinical chemistry laboratory classically provides only limited help in distinguishing between reactive thrombocytosis (RT) and autonomous thrombocytosis, where platelet production escapes normal regulatory processes, and which is seen in myeloproliferative diseases (MPD) such as essential thrombocythemia and polycythemia vera. We explored the clinical use of platelet distribution width (PDW) in the differential diagnosis of thrombocytosis. During a 3-month period, 250 patients presenting with a platelet count >500 × 109/L were studied; 174 were classified as having RT, 42 had a diagnosis of MPD, and 34 patients were excluded because they had a hemopathy different from MPD, and either did or did not present a known etiologic factor for RT. First, we determined that in the RT group the value of PDW was closely linked to both mean platelet volume (MPV) and platelet count (PLT) (PDW = 79.5 − 0.005 PLT − 3.5 MPV; r = 0.848, R2 = 0.720). Therefore a new parameter, PDWresidual, was defined (PDWresidual = PDWobserved − PDWexpected). Second, the discrimination between reactive and autonomous thrombocytosis obtained with PDWresidual was compared with that obtained with either PDW, MPV, or PLT. PDWresidual proved much more powerful than each of the other parameters used separately: 76% of MPD patients had a PDWresidual above the 95th percentile value of the RT population and none of the MPD patients had a PDWresidualbelow the 50th percentile. Thus, the combined interpretation of PLT, MPV, and PDW through the use of a PDWresidualappears highly useful in the differential diagnosis of thrombocytosis. Also, through simple modeling, more information can be drawn from parameters such as PDW that hitherto were mostly discarded as being without clinical interest.

Relationship between platelet volume indices with macrovascular and peripheral neuropathy complications in type 2 diabetic patients (2型糖尿病患者血小板容积参数与大血管及外周神经并发症的相关性研究)

“…Studies have also shown that PDW was useful in the differential diagnosis of thrombocytosis and thrombocytopenia. 23,24 Our results further support the measurements of MPV and PDW would be useful for independent predictors of diabetes macrovascular complications, which need more studies to confirm. Diabetic neuropathy is one of the most serious complications of diabetes, with an estimated prevalence of 13.1% in patients with known diabetes and 7.1% in newly diagnosed diabetic patients.…”

Canine reference intervals for the Sysmex XT‐2000iV hematology analyzer

“…However, the instrument has not been validated for LFR, MFR, HFR, IRF, MPV, P‐LCR, PCT, and PDW; thus, these data may be useful in future studies. However, the clinical value of these new indices has been investigated in only a few studies in human 19–21 and veterinary hematology 22,23 . Within‐laboratory precision of the analyzer with human control samples and repeatability with canine blood were satisfactory.…”

Evaluation of Platelet Parameters in Children with Autism Spectrum Disorder: Elongated Collagen‐Adenosine Diphosphate and Collagen‐Epinephrine Closure Times

“…However only nine patients presenting with CARS scored falling in the severe range participated in this study and studies with higher sample sizes of severe autism are needed to explicate this point. PDW is an indication of variation in volume of platelets and increases in the presence of platelet anisocytosis [Osselaer, Jamart, & Scheiff, 1997]. PDW is a test obtained from direct flow cytometric measurement of platelet cell volume and is not well documented at the clinical setting (Dixon, 1997;van der Loo & Martin, 1997).…”