Dear Editor, In a recent issue of your journal, we were grateful to read an interesting article by Icli et al. [1] assessing the mean platelet volume (MPV), which is an indicator of platelet activation in patients with infective endocarditis (IE), and changes in MPV values after antibiotic treatment. They found that the MPV was significantly higher among patients with IE when compared with the control group and that the MPV values of patients with IE decreased significantly with treatment (from 9.86 ± 1.1 to 7.86 ± 1.0 fl, p < 0.01). We thank these authors for their complementary contributions to the area of platelet activation in IE patients.
Platelets exhibit intraindividual and interindividual heterogeneity in their size and density. MPV, the most commonly used measure of platelet size, is a simple, inexpensive and widely available marker of platelet reactivity. It has been shown that MPV is associated with various cardiovascular conditions including IE and adverse outcomes [2]. Previous studies with IE patients show that normalization of inflammatory markers with antimicrobial therapy is a good predictor of favorable late outcome [3,4]. In addition, one of the determinants of an adverse outcome in IE is the presence of systemic embolization, particularly cerebral embolization. IE vegetations consist of bacteria, platelets and inflammatory cells in a fibrin mesh. Thus, the results of the current study should be combined and endorsed with clinical outcomes like systemic embolization and correlation with other proinflammatory markers like C-reactive protein [3,4] and neutrophil-to-lymphocyte ratio [5]. Medications like aspirin which can affect the MPV values should be reported along with the other medications administered to patients.
References
- 1.Icli A, Tayyar S, Varol E, et al. Mean platelet volume is increased in infective endocarditis and decreases after treatment. Med Princ Pract. 2013;22:270–273. doi: 10.1159/000345393. [DOI] [PMC free article] [PubMed] [Google Scholar]
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