To the editor,
We read with great interest the article “Mean Platelet Volume and Mean Platelet Volume/Platelet Count Ratio in Infective Endocarditis” by Cho et al. [Citation1]. The authors concluded that higher MPV level is associated with infective endocarditis (IE) and might be a diagnostic marker of this disease.
MPV describes the size of platelets and is utilized as a marker of platelet activation and function [Citation2]. MPV is an emerging marker of inflammation and also intensity of inflammation [Citation3]. IE-related endothelial damage and hypercoagulability may be associated with inflammation and these conditions may lead to life-threatening complications such as thromboembolism and even death [Citation1].
In previous studies, it was demonstrated that diabetes mellitus, peripheral artery disease, acute coronary syndromes, autoimmune disorders, thrombocytopenia, congestive heart failure, acute pulmonary emboli, thyroid functional abnormalities, local or systemic infections, malignancy, inflammatory diseases, and many drugs may potentially affect MPV levels [Citation2]. Thus, it would have been better if the authors had mentioned these MPV-effecting factors while assessing the associations between MPV and IE.
MPV may alter in subacute and acute IE. Subacute forms of IE or prosthetic valve IE may have different presentations because of biofilm and low-level inflammatory responses. Even though the number of the patients were limited in this study, it would also have been relevant if the authors had discriminated between subacute IE and acute IE. Recent studies have demonstrated that B-type natriuretic peptide (BNP), procalcitonin (PCT), cystatin C, and matrix metalloproteinase-9 levels are found to be associated with the infective endocarditis (IE) [Citation4–6]. In this context, the authors could have compared their cases according to these parameters affecting the prognosis and severity of this disease.
Medication may also alter MPV in patients with IE, so it would have been useful if the patients were described in greater detail in terms of antibiotic use and/or other medications. In addition, it would also have been better if the authors indicated the elapsed time between taking the blood samples and measuring MPV since waiting period prior to analysis may affect MPV value [Citation7].
We believe that the findings of Cho et al. will lead to further research regarding the relationship between MPV and IE [Citation1]. Anyway, it should be kept in mind that MPV alone without other variables (e.g., C-reactive protein, PCT, and BNP) may not provide certain information about the inflammatory status of the patient with IE.
Declaration of interest
The authors have no competing interests to declare.
References
- Cho SY, Jeon YL, Kim W, Kim WS, Lee HJ, Lee WI, Park TS. Mean platelet volume and mean platelet volume/platelet count ratio in infective endocarditis. Platelets. 2013 Nov 8. [Epub ahead of print]
- Karagöz E, Tanoglu A. Mean Platelet Volume: An Emerging Diagnostic Factor of Recurrent Aphthous Stomatitis and Behcet Disease. Angiology. 2013 Dec 9. [Epub ahead of print]
- Gasparyan AY, Ayvazyan L, Mikhailidis DP, Kitas GD. Mean platelet volume: A link between thrombosis and inflammation? Curr Pharm Des 2011;17:47–58
- Cornelissen CG, Frechen DA, Schreiner K, Marx N, Krüger S. Inflammatory parameters and prediction of prognosis in infective endocarditis. BMC Infect Dis 2013;13:272
- Bjurman C, Snygg-Martin U, Olaison L, Fu ML, Hammarsten O. Cystatin C in a composite risk score for mortality in patients with infective endocarditis: A cohort study. BMJ Open 2012;12:2
- Thuny F, Habib G, Le Dolley Y, Canault M, Casalta J-P, Verdier M, Avierinos J-F, Raoult D, Mege J-L, Morange P-E, Alessi M-C. Circulating matrix metalloproteinases in infective endocarditis: A possible marker of the embolic risk. PLoS One 2011;6:e18830
- Demirin H, Ozhan H, Ucgun T, Celer A, Bulur S, Cil H, Gunes C, Yildirim HA. Normal range of mean platelet volume in healthy subjects: Insight from a large epidemiologic study. Thromb Res 2011;128:358–360