LETTER TO THE EDITOR
The relationship between mean platelet volume and varicocele doi: 10.1111/and.12260 With great interest we read the article by Coban et al. (2014). They assessed the relationship between mean platelet volume (MPV), platelet count (PLT), platelet distribution width (PDW) and varicocele. MPV values were statistically significantly higher, whereas PLT and PDW values were statistically significantly lower, in the varicocele group than in control group, respectively. There was no significant correlation between MPV, PDW and the varicocele grade and spermatic vein diameter. This is an interesting study with a relatively large sample size. However, we think that there are methodological problems in the study. Firstly, the method used for MPV assessment is not clear. They used the EDTA tube for blood sample collection. It is clear that MPV increases over time in EDTA-anticoagulated samples, and this increase was shown to be proportional with the delay in time between sample collection and laboratory analysis (Bath & Butterworth, 1996). With impedance counting, the MPV increases over time as platelets swell in EDTA, with increases of 7.9% within 30 min and an overall increase of 13.4% over 24 h (Lance et al., 2010). The recommended optimal measuring time of MPV is 2 h after venipuncture (Lance et al., 2010). It would be better if they clarified this situation in this retrospective study. Secondly, it has to be kept in mind that there are significant associations of MPV with some cardiovascular conditions like smoking, obesity, hyperlipidaemia, hypertension, coronary artery disease, metabolic syndrome, statin use and atrial fibrillation (Vizioli et al., 2009; Varol et al., 2010, 2013). They excluded coronary artery disease, hypertension, diabetes mellitus, renal failure and haematological disorders. However, they did not mention about the body mass index, smoking status, blood lipid levels and presence of metabolic syndrome. It has been shown that obesity, hyperlipidaemia, smoking and metabolic syndrome increase MPV values (Vizioli et al., 2009; Varol et al., 2010, 2013). Absolutely, these factors should have been considered in assessment. The difference of MPV between groups might be due to these associated factors.
© 2015 Blackwell Verlag GmbH Andrologia 2015, 47, 245
Mean platelet volume is universally available with routine blood counts by automated hemograms and a simple and easy method of assessing platelet function. In comparison with smaller ones, larger platelets have more granules, aggregate more rapidly with collagen, have higher thromboxane A2 level and express more glycoprotein Ib and IIb/IIIa receptors (Park et al., 2002; Vizioli et al., 2009). We believe that MPV can be affected by many inflammatory and cardiovascular risk factors. Because of that, all confounding factors should be to taken into account. Also standardised methods should be used for assessment of MPV. E. Varol & M. Ozaydin Department of Cardiology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey e-mail: [email protected] References Bath PM, Butterworth RJ (1996) Platelet size: measurement, physiology and vascular disease. Blood Coagul Fibrinolysis 7:157–161. Coban S, Kelesß I, Bıyık I, G€ uzelsoy M, T€ urkoglu AR, Ozg€ unay T, Ocak N (2014) Is there any relationship between mean platelet volume and varicocele? Andrologia doi: 10.1111/and. 12220 [Epub ahead of print]. Lance MD, van Oerle R, Henskens YM, Marcus MA (2010) Do we need time adjusted mean platelet volume measurements? Lab Hematol 16:28–31. Park Y, Schoene N, Harris W (2002) Mean platelet volume as an indicator of platelet activation: methodological issues. Platelets 13:301–306. Varol E, Akcay S, Icli A, Yucel H, Ozkan E, Erdogan D, Ozaydin M (2010) Mean platelet volume in patients with prehypertension and hypertension. Clin Hemorheol Microcirc 45:67–72. Varol E, Icli A, Kocyigit S, Erdogan D, Ozaydin M, Dogan A (2013) Effect of smoking cessation on mean platelet volume. Clin Appl Thromb Hemost 19:315–319. Vizioli L, Muscari S, Muscari A (2009) The relationship of mean platelet volume with the risk and prognosis of cardiovascular diseases. Int J Clin Pract 63:1509–1515.
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The relationship between mean platelet volume and varicocele doi: 10.1111/and.12260 With great interest we read the article by Coban et al. (2014). They assessed the relationship between mean platelet volume (MPV), platelet count (PLT), platelet distribution width (PDW) and varicocele. MPV values were statistically significantly higher, whereas PLT and PDW values were statistically significantly lower, in the varicocele group than in control group, respectively. There was no significant correlation between MPV, PDW and the varicocele grade and spermatic vein diameter. This is an interesting study with a relatively large sample size. However, we think that there are methodological problems in the study. Firstly, the method used for MPV assessment is not clear. They used the EDTA tube for blood sample collection. It is clear that MPV increases over time in EDTA-anticoagulated samples, and this increase was shown to be proportional with the delay in time between sample collection and laboratory analysis (Bath & Butterworth, 1996). With impedance counting, the MPV increases over time as platelets swell in EDTA, with increases of 7.9% within 30 min and an overall increase of 13.4% over 24 h (Lance et al., 2010). The recommended optimal measuring time of MPV is 2 h after venipuncture (Lance et al., 2010). It would be better if they clarified this situation in this retrospective study. Secondly, it has to be kept in mind that there are significant associations of MPV with some cardiovascular conditions like smoking, obesity, hyperlipidaemia, hypertension, coronary artery disease, metabolic syndrome, statin use and atrial fibrillation (Vizioli et al., 2009; Varol et al., 2010, 2013). They excluded coronary artery disease, hypertension, diabetes mellitus, renal failure and haematological disorders. However, they did not mention about the body mass index, smoking status, blood lipid levels and presence of metabolic syndrome. It has been shown that obesity, hyperlipidaemia, smoking and metabolic syndrome increase MPV values (Vizioli et al., 2009; Varol et al., 2010, 2013). Absolutely, these factors should have been considered in assessment. The difference of MPV between groups might be due to these associated factors.
© 2015 Blackwell Verlag GmbH Andrologia 2015, 47, 245
Mean platelet volume is universally available with routine blood counts by automated hemograms and a simple and easy method of assessing platelet function. In comparison with smaller ones, larger platelets have more granules, aggregate more rapidly with collagen, have higher thromboxane A2 level and express more glycoprotein Ib and IIb/IIIa receptors (Park et al., 2002; Vizioli et al., 2009). We believe that MPV can be affected by many inflammatory and cardiovascular risk factors. Because of that, all confounding factors should be to taken into account. Also standardised methods should be used for assessment of MPV. E. Varol & M. Ozaydin Department of Cardiology, Faculty of Medicine, Suleyman Demirel University, Isparta, Turkey e-mail: [email protected] References Bath PM, Butterworth RJ (1996) Platelet size: measurement, physiology and vascular disease. Blood Coagul Fibrinolysis 7:157–161. Coban S, Kelesß I, Bıyık I, G€ uzelsoy M, T€ urkoglu AR, Ozg€ unay T, Ocak N (2014) Is there any relationship between mean platelet volume and varicocele? Andrologia doi: 10.1111/and. 12220 [Epub ahead of print]. Lance MD, van Oerle R, Henskens YM, Marcus MA (2010) Do we need time adjusted mean platelet volume measurements? Lab Hematol 16:28–31. Park Y, Schoene N, Harris W (2002) Mean platelet volume as an indicator of platelet activation: methodological issues. Platelets 13:301–306. Varol E, Akcay S, Icli A, Yucel H, Ozkan E, Erdogan D, Ozaydin M (2010) Mean platelet volume in patients with prehypertension and hypertension. Clin Hemorheol Microcirc 45:67–72. Varol E, Icli A, Kocyigit S, Erdogan D, Ozaydin M, Dogan A (2013) Effect of smoking cessation on mean platelet volume. Clin Appl Thromb Hemost 19:315–319. Vizioli L, Muscari S, Muscari A (2009) The relationship of mean platelet volume with the risk and prognosis of cardiovascular diseases. Int J Clin Pract 63:1509–1515.
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