Predictive Effect of Mean Platelet Volume in Patients with Portal Vein Thrombosis: A Meta-analysis of Case-control Studies

Portal Vein Thrombosis Might Develop by COVID-19 Infection or Vaccination: A Systematic Review of Case-Report Studies

Background and Objective: Infection by the novel coronavirus disease 2019 (COVID-19) has been associated with different types of thrombotic complications same as portal vein thrombosis (PVT). However, by emerging vaccines of COVID, the thrombosis did not seem to be concerning anymore. Until new findings showed that, the vaccine of COVID itself can cause PVT.

Method: We performed an electronic search in PubMed, Scopus, and Web of Sciences to evaluate the possibility of occurring PVT due to infection and vaccination of COVID-19. The results were reported in a narrative method and categorized into tables.

Result: Overall, 40 cases of PVT from 34 studies were reviewed in this article. The prevalence of PVT following COVID-19 was more remarkable in males. However, it was more common in females after vaccinations of COVID-19 in the reviewed cases. Regardless of etiology, 20 of PVT cases reviewed in this article had at least one comorbidity. The most common clinical presentation was abdominal pain (AP). After anticoagulant therapies, most of the patients improved or discharged.

Conclusion: As long as the laboratory findings are not appropriate enough to predict PVT, the diagnosis of this complication with whatever underlying reason is challengeable, while rapid diagnosis and treatment of that are vital. Therefore, by providing available data in an organized way, we aimed to prepare the information of infected patients for better and easier future diagnosis of PVT in new cases.

Evaluation of Platelet Indices in Patients with Splanchnic Vein Thrombosis

Splanchnic vein thrombosis (SVT) is a rare and lethal form of venous thrombosis. The role of platelet indices (PI's) is not well studied in SVT. The present study was aimed to assess if the PI's have a significant association with SVT. This was a prospective case control study from coagulation laboratory of Hematology department. A total 100 cases of SVT and 80 controls were screened for PI's (MPV, PCT & PDW) and platelet count (PC) along with routine thrombophilic risk factors. The SVT cases were divided into 3 subgroups, that comprised of EHPVO/ PVT (n = 69), BCS (n = 27), and MVT (n = 4). The mean PC and PCT were significantly lower in patients than the controls. The PDW was significantly higher in cases than in the controls and MPV was relatively higher in cases however did not show statistical significance. In addition, 16 patients were found to have deranged thrombophilic risk factors. Among these, 8 cases had inherited risk factors (2: FVL; 5: PC; 1: PS) and 8 cases had acquired risk factors (2: APL; and 5: multiple factors and one case had both FVL mutation and APL positivity). The PDW and PCT together with PC were found to significantly differ in SVT cases than in controls, particularly in idiopathic cases. It may be worthwhile to explore the utility of PI's as a potential risk factor in SVT.

Supplementary Information

The online version contains supplementary material available at (10.1007/s12288-021-01400-5).

Mean platelet volume in arterial and venous thrombotic disorders

The mean platelet volume (MPV) is an easy, rapid and inexpensive laboratory parameter which basically mirrors platelet size. Due to the essential role of platelets in hemostasis, many studies have assessed the MPV value in patients with arterial and venous thrombotic disorders. These have then been summarized in some interesting meta-analyses and recent studies that will be discussed in this narrative review. Taken together, the currently available evidence suggests that the MPV may be substantially increased in concomitance with acute episodes of coronary artery disease, venous thromboembolism, portal vein thrombosis, stroke, erectile dysfunction and preeclampsia. In many of these conditions, an increased MPV value may also be associated with unfavorable outcomes. Despite these convincing findings, some important technical issues should be considered for improving the clinical usefulness of this measure. These essentially include anticoagulant, timing of sample collection, the sample storage conditions, the influence of the analytical techniques, the approaches used for its calculation, the accurate definition of reference ranges and diagnostic cut-offs, as well as the current lack of standardization, which makes data obtained with different techniques/analyzers poorly comparable. Provided that the impact of these variables can be abated or minimized, the MPV can gain a valuable role in the laboratory workout of many arterial and venous thrombotic disorders.

Platelet count and mean volume in acute stroke: a systematic review and meta-analysis

Changes of mean platelet volume (MPV) and platelet count (PC) could be a marker or a predictor of acute stroke (AS). We conducted a systematic review and meta-analysis of the published literature on the reporting of MPV and PC in AS. Studies were included in accordance with Patient Population or Problem, Intervention, Comparison, Outcomes, and Setting framework. The PRISMA strategy was used to report findings. Risk of bias was assessed with the Newcastle-Ottawa Scale. We included 34 eligible articles retrieved from the literature. PC was significantly lower in AS patients [standardized mean difference (SMD) = - 0.30, (95% CI: - 0.49 to - 0.11), N = 2492, P = .002] compared with controls (N = 3615). The MPV was significantly higher [SMD = 0.52 (95% CI: 0.28-0.76), N = 2739, P < .001] compared with controls (N = 3810). Subgroup analyses showed significantly lower PC in both ischemic stroke (Difference SMD = -0.18, 95% CI: -0.35-0.01) and hemorrhagic stroke (-0.94, -1.62 to -0.25), but only samples by citrate anticoagulant showed significantly lower result for patients compared to controls (-0.36, -0.68 to -0.04). Ischemic stroke patients had higher MPV (0.57, 0.31-0.83), and samples by Ethylenediaminetetraacetic acid (EDTA) anticoagulant showed significantly higher result for patients compared to controls (0.86, 0.55-1.17). PC and MPV appeared to be significantly different between patients with AS and control populations. MPV was significantly higher in ischemic stroke and PC was significantly lower in both ischemic and hemorrhagic strokes. These characteristics might be related to AS and associated with it. It is advisable to pay attention to elapsed time between phlebotomy and hematology analysis, anticoagulant and hemocytometer types in AS.

SYSTEMATIC REVIEW REGISTRATION

This meta-analysis is registered on the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42017067864 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=67864).

Evaluation of complete blood count parameters in cardiovascular diseases: An early indicator of prognosis?

BACKGROUND

Studies have been conducted to evaluate the correlation between complete blood count (CBC) indices and cardiovascular diseases (CVDs). Considering the dispersion of these studies as well as reports on prognostic value of CBC parameters in CVDs, we have summarized these findings as a review article for the first time.

METHODS

Relevant English language literature was searched and retrieved from Google Scholar search engine and PubMed database (1996-2018). We used "Complete blood count", "Cardiovascular disease", "Red cell distribution width", and "Mean platelet volume" as keywords.

RESULTS

Numerous studies indicated that red cell distribution width (RDW) is an independent prognostic biomarker in relation to CVD diseases. MPV is another considerable prognostic biomarker for CVDs. Elevations of inflammatory markers such as neutrophil to lymphocyte ratio (NLR) in CVD patients (especially in myocardial infarction and heart failure) can be considered as a factor of poor prognosis.

CONCLUSIONS

RDW can be used as a valuable independent biomarker to investigate the prognosis of patients with heart failure (HF), atherosclerosis, myocardial infarction (MI), and other CVDs. Rapid and stable increase in MPV makes it a reliable prognostic/diagnostic parameter in CVDs such as MI and unstable angina. Among different inflammatory markers the evaluation of total white blood cell count, NLR, monocyte to high-density lipoprotein ratio (MHR) and platelet to lymphocyte ratio (PLR) may have a high value in predicting the prognosis of different CVDs including MI, HF and atherosclerosis in patients.