Graefes Arch Clin Exp Ophthalmol (2013) 251:2839–2840 DOI 10.1007/s00417-013-2488-z
LETTER TO THE EDITOR
Letter to the editor: mean platelet volume and diabetic retinopathy Cengiz Beyan & Esin Beyan
Received: 22 August 2013 / Accepted: 1 October 2013 / Published online: 23 October 2013 # Springer-Verlag Berlin Heidelberg 2013
Dear Editor, We read with great interest the article by Ayhan Tuzcu et al. about the relationship between mean platelet volume (MPV) and retinopathy in patients with type 2 diabetes mellitus [1]. The authors performed a study aimed to evaluate the effect of MPV on diabetic retinopathy in patients with type 2 diabetes mellitus. They suggested that the risks of development of diabetic retinopathy and proliferative diabetic retinopathy increase with higher MPV values. We would like to discuss this study. The sentence of “MPV is a parameter of platelet function” does not reflect the current literature. The MPV and/or other platelet indices are not used as platelet function tests [2]. Light transmission aggregometry is the gold standard for the study of patients with defects of platelet function [3]. Beyan et al. investigated whether platelet indices have a correlation with functional aggregation responses using optical method in healthy adults, and evaluated the predictive significance of platelet indices over platelet aggregation responses [4]. They did not find any correlation between platelet aggregation responses obtained with turbidometric platelet aggregometry
C. Beyan (*) Department of Hematology, Gulhane Military Medical Academy, Etlik, 06018 Ankara, Turkey e-mail: [email protected] C. Beyan e-mail: [email protected] E. Beyan Department of Internal Medicine, Kecioren Training and Research Hospital, Ankara, Turkey
and platelet indices including platelet count, MPV, platelet distribution width, and plateletcrit proposed as indicators of certain pathologic conditions, and it does not seem possible to use platelet indices as a direct indicator of platelet function. Accurate measurements of platelet count and size are important for diagnostic, therapeutic, and research purposes. Lancé et al. reviewed the preanalytical variability of the MPV, and proposed a possible approach to standardization [5]. MPV does not routinely use a part of the complete blood count because of the ethylenediaminetetraacetic acid (EDTA)induced changes over time [6]. EDTA-induced platelet shape changes result in a progressive increase in MPV with impedance technology. In general, the MPV increases up to 30 % within 5 min of exposure, and increases further by 10 to 15 % over the next 2 h [7]. Some investigators have reported variable increases in MPV with EDTA storage up to 50 % [6]. The effect of EDTA on MPV with optical analysis is less well-documented, but appears to be unpredictable, decreasing in many patient samples and increasing in others [6]. Lancé et al. performed a study to standardize the measurements of MPV. They suggested that timing is important when measuring the MPV, and that the optimal measurement time should be 120 min with EDTA after venipuncture [8]. Furthermore, different technologies for measuring the MPV give different results. Studies comparing results from different instruments have shown MPV variability up to 40 % [6]. The MPV measurement time, the MPV measurement method, and using technologies for the measurement of MPV were not described in this retrospective study. As a conclusion, the MPV measurement protocol should be standardized before the using of MPV for diabetic retinopathy in patients with type 2 diabetes.
2840 Conflict of interest The authors have no conflict of interest.
References 1. Ayhan Tuzcu E, Arıca S, Ilhan N, Daglioglu M, Coskun M, Ilhan O, Ustun I (2013) Relationship between mean platelet volume and retinopathy in patients with type 2 diabetes mellitus. Graefes Arch Clin Exp Ophthalmol Aug 17 [Epub ahead of print]. doi:10.1007/ s00417-013-2444-y 2. Harrison P (2013) Platelet function testing. UpToDate. http://www. uptodate.com/contents/platelet-function-testing. Accessed 22 Aug 2013 3. Cattaneo M (2009) Light transmission aggregometry and ATP release for the diagnostic assessment of platelet function. Semin Thromb Hemost 35:158–167. doi:10.1055/s-0029-1220324
Graefes Arch Clin Exp Ophthalmol (2013) 251:2839–2840 4. Beyan C, Kaptan K, Ifran A (2006) Platelet count, mean platelet volume, platelet distribution width, and plateletcrit do not correlate with optical platelet aggregation responses in healthy volunteers. J Thromb Thrombolysis 22:161–164. doi:10.1007/s11239-006-9014-7 5. Lancé MD, Sloep M, Henskens YM, Marcus MA (2012) Mean platelet volume as a diagnostic marker for cardiovascular disease: drawbacks of preanalytical conditions and measuring techniques. Clin Appl Thromb Hemost 18:561–568. doi:10.1177/ 1076029612458147 6. George TI (2013) Automated hematology instrumentation. UpToDate. http://www.uptodate.com/contents/automated-hematologyinstrumentation. Accessed 22 Aug 2013 7. Jackson SR, Carter JM (1993) Platelet volume: laboratory measurement and clinical application. Blood Rev 7:104–113 8. Lancé MD, van Oerle R, Henskens YM, Marcus MA (2010) Do we need time adjusted mean platelet volume measurements? Lab Hematol 16:28–31. doi:10.1532/LH96.10011
LETTER TO THE EDITOR
Letter to the editor: mean platelet volume and diabetic retinopathy Cengiz Beyan & Esin Beyan
Received: 22 August 2013 / Accepted: 1 October 2013 / Published online: 23 October 2013 # Springer-Verlag Berlin Heidelberg 2013
Dear Editor, We read with great interest the article by Ayhan Tuzcu et al. about the relationship between mean platelet volume (MPV) and retinopathy in patients with type 2 diabetes mellitus [1]. The authors performed a study aimed to evaluate the effect of MPV on diabetic retinopathy in patients with type 2 diabetes mellitus. They suggested that the risks of development of diabetic retinopathy and proliferative diabetic retinopathy increase with higher MPV values. We would like to discuss this study. The sentence of “MPV is a parameter of platelet function” does not reflect the current literature. The MPV and/or other platelet indices are not used as platelet function tests [2]. Light transmission aggregometry is the gold standard for the study of patients with defects of platelet function [3]. Beyan et al. investigated whether platelet indices have a correlation with functional aggregation responses using optical method in healthy adults, and evaluated the predictive significance of platelet indices over platelet aggregation responses [4]. They did not find any correlation between platelet aggregation responses obtained with turbidometric platelet aggregometry
C. Beyan (*) Department of Hematology, Gulhane Military Medical Academy, Etlik, 06018 Ankara, Turkey e-mail: [email protected] C. Beyan e-mail: [email protected] E. Beyan Department of Internal Medicine, Kecioren Training and Research Hospital, Ankara, Turkey
and platelet indices including platelet count, MPV, platelet distribution width, and plateletcrit proposed as indicators of certain pathologic conditions, and it does not seem possible to use platelet indices as a direct indicator of platelet function. Accurate measurements of platelet count and size are important for diagnostic, therapeutic, and research purposes. Lancé et al. reviewed the preanalytical variability of the MPV, and proposed a possible approach to standardization [5]. MPV does not routinely use a part of the complete blood count because of the ethylenediaminetetraacetic acid (EDTA)induced changes over time [6]. EDTA-induced platelet shape changes result in a progressive increase in MPV with impedance technology. In general, the MPV increases up to 30 % within 5 min of exposure, and increases further by 10 to 15 % over the next 2 h [7]. Some investigators have reported variable increases in MPV with EDTA storage up to 50 % [6]. The effect of EDTA on MPV with optical analysis is less well-documented, but appears to be unpredictable, decreasing in many patient samples and increasing in others [6]. Lancé et al. performed a study to standardize the measurements of MPV. They suggested that timing is important when measuring the MPV, and that the optimal measurement time should be 120 min with EDTA after venipuncture [8]. Furthermore, different technologies for measuring the MPV give different results. Studies comparing results from different instruments have shown MPV variability up to 40 % [6]. The MPV measurement time, the MPV measurement method, and using technologies for the measurement of MPV were not described in this retrospective study. As a conclusion, the MPV measurement protocol should be standardized before the using of MPV for diabetic retinopathy in patients with type 2 diabetes.
2840 Conflict of interest The authors have no conflict of interest.
References 1. Ayhan Tuzcu E, Arıca S, Ilhan N, Daglioglu M, Coskun M, Ilhan O, Ustun I (2013) Relationship between mean platelet volume and retinopathy in patients with type 2 diabetes mellitus. Graefes Arch Clin Exp Ophthalmol Aug 17 [Epub ahead of print]. doi:10.1007/ s00417-013-2444-y 2. Harrison P (2013) Platelet function testing. UpToDate. http://www. uptodate.com/contents/platelet-function-testing. Accessed 22 Aug 2013 3. Cattaneo M (2009) Light transmission aggregometry and ATP release for the diagnostic assessment of platelet function. Semin Thromb Hemost 35:158–167. doi:10.1055/s-0029-1220324
Graefes Arch Clin Exp Ophthalmol (2013) 251:2839–2840 4. Beyan C, Kaptan K, Ifran A (2006) Platelet count, mean platelet volume, platelet distribution width, and plateletcrit do not correlate with optical platelet aggregation responses in healthy volunteers. J Thromb Thrombolysis 22:161–164. doi:10.1007/s11239-006-9014-7 5. Lancé MD, Sloep M, Henskens YM, Marcus MA (2012) Mean platelet volume as a diagnostic marker for cardiovascular disease: drawbacks of preanalytical conditions and measuring techniques. Clin Appl Thromb Hemost 18:561–568. doi:10.1177/ 1076029612458147 6. George TI (2013) Automated hematology instrumentation. UpToDate. http://www.uptodate.com/contents/automated-hematologyinstrumentation. Accessed 22 Aug 2013 7. Jackson SR, Carter JM (1993) Platelet volume: laboratory measurement and clinical application. Blood Rev 7:104–113 8. Lancé MD, van Oerle R, Henskens YM, Marcus MA (2010) Do we need time adjusted mean platelet volume measurements? Lab Hematol 16:28–31. doi:10.1532/LH96.10011
