Assessment of Mean Platelet Volume in Patients with Systemic Lupus Erythematosus

Role of Platelets in Rheumatic Chronic Autoimmune Inflammatory Diseases

Platelets are essential in maintaining blood homeostasis and regulating several inflammatory processes. They constantly interact with immune cells, have immunoregulatory functions, and can affect, through immunologically active substances, endothelium, leukocytes, and other immune response components. In reverse, inflammatory and immune processes can activate platelets, which might be significant in autoimmune disease progression and arising complications. Thus, considering this interplay, targeting platelet activity may represent a new approach to treatment of autoimmune diseases. This review aims to highlight the role of platelets in the pathogenic mechanisms of the most frequent chronic autoimmune inflammatory diseases to identify gaps in current knowledge and to provide potential new targets for medical interventions.

Association between Mean Platelet Volume and Systemic Lupus Erythematosus: A Meta-Analysis

Background

This meta-analysis aimed to investigate the association between mean platelet volume (MPV) and systemic lupus erythematosus (SLE) disease activity, and laboratory parameters including the SLE Disease Activity Index (SLEDAI), C3 levels, anti-double-stranded DNA (anti-dsDNA) antibodies, and erythrocyte sedimentation rate (ESR).

Methods

The Medline, Embase, and Cochrane databases were searched comprehensively to identify relevant articles. Meta-Analyses were performed to assess differences in MPV between patients with SLE and control groups and between active and inactive SLE. A separate meta-analysis explored correlation coefficients between MPV and SLEDAI, C3, anti-dsDNA, and ESR.

Results

Fourteen studies comprising 659 patients with SLE and 682 controls were included. No significant difference in MPV was found between patients with SLE and control groups (standardized mean difference [SMD]: 0.406; 95% confidence interval [CI]: -0.087 to 0.899; P = 0.107). When stratified by ethnicity, the Arab population displayed markedly elevated MPV levels within the SLE group (SMD: 1.032; 95% CI: 0.475-1.588; P <0.001), unlike their European and Asian counterparts. MPV levels were higher in the active disease group than in the inactive group, particularly among the Arab population (SMD: 2.100; 95% CI: 0.406-3.794; P = 0.015), while no significant difference was observed within the Asian population (SMD: -1.493; 95% CI = -4.465 to 1.479; P = 0.325). MPV did not correlate with SLEDAI (correlation coefficient: 0.252; 95% CI: -0.016 to 0.486; P = 0.065), ESR, C3, or anti-dsDNA.

Conclusion

MPV levels were generally higher in patients with SLE among the Arab population. Moreover, MPV and disease activity were positively correlated within the Arab population, underscoring the potential of MPV as a disease activity indicator in specific ethnic groups.

The mean platelet volume (MPV) in patients with systemic lupus erythematosus (SLE) and its correlation with disease activity: a cross-sectional/case-control study

Introduction

Systemic lupus erythematosus (SLE) is a systemic disease, with unknown etiology. The authors aimed in this study to determine the connection between mean platelet volume (MPV) and disease activity of SLE. Although it has been studied in other rheumatological conditions like rheumatoid arthritis, its role in adult patients with SLE needs to be defined, especially in Syria.

Materials and methods

The authors have included in a cross-sectional study, 80 patients with SLE and 80 controls.The SLE group was divided into two groups based on their disease activity index: the active disease group and the non-active disease group.In all groups, MPV and erythrocyte sedimentation rate (ESR) were analyzed. Clinical findings and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) were evaluated in all patients.

Results

MPV was significantly lower in SLE patients compared to the control group (8.49±1.2 fl and 10.0±0.5 fl, respectively) (P=0.001). A decrease in MPV below the cut-off value (7.2 fl) increased the risk of active disease by an odds ratio of 9.79 (95% CI: 3.4-27.9) (P<0.001).

Conclusion

MPV may be a disease activity indicator in patients with SLE. MPV is reduced in patients with active SLE and presents an inverse correlation with SLEDAI.

Platelets and the Lectin Pathway of Complement Activation in Patients with Systemic Lupus Erythematosus or Antiphospholipid Syndrome

Background  Patients with systemic lupus erythematosus (SLE) have an increased risk of thrombosis even when they do not have antiphospholipid syndrome (APS). Interactions between complement activation and activated platelets have been suggested in SLE and APS and could play a role in the increased thrombosis risk. Objectives  To explore factors potentially related to the prothrombotic pathophysiology in patients with SLE, primary APS, and healthy controls, by investigating lectin pathway proteins (LPPs), complement activation, platelet aggregation, and platelet activation. Methods  This cross-sectional cohort study included 20 SLE patients, 17 primary APS, and 39 healthy controls. Flow cytometry and light transmission aggregometry were used to assess platelet activation and aggregation. Using time-resolved immunofluorometric assays, the plasma concentrations of 11 LPPs and C3dg, reflecting complement activation, were measured. Results  H-ficolin plasma concentrations were higher in SLE and APS patients than in controls ( p  = 0.01 and p  = 0.03). M-ficolin was lower in SLE than in APS ( p  = 0.01) and controls ( p  = 0.03). MAp19 was higher in APS patients than in SLE patients ( p  = 0.01) and controls ( p  < 0.001). In APS patients, MASP-2 and C3dg correlated negatively with platelet activation. Platelet-bound fibrinogen after agonist stimulation and C3dg concentrations correlated negatively with platelet activation. Conclusion  We observed significant differences between SLE and APS patients regarding complement proteins and platelet activation. Particularly the negative correlations between MASP-2 and C3dg with platelet activation only observed in APS patients suggest that interactions between complement activation and platelets differ in SLE and APS.

Mean platelet volume to lymphocyte ratio and platelet distribution width to lymphocyte ratio in Iraqi patients diagnosed with systemic lupus erythematosus

Introduction

The mean platelet volume to lymphocyte ratio (MPVLR) and platelet distribution width to lymphocyte ratio (PDWLR) have the potential to serve as markers of inflammation which may indicate disease activity. The mean platelet volume to lymphocyte ratio and PDWLR were assessed in patients with systemic lupus erythematosus (SLE) in this study.

Material and methods

Sixty-two patients with systemic lupus erythematosus and 79 controls who were age and gender matched were included. Their sociodemographic information, as well as disease activity scores based on the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), disease duration, current medications, lymphocytes, platelets, platelet distribution width (PDW), and mean platelet volume (MPV), anti-nuclear antibody (ANA), anti-double stranded deoxyribonucleic acid (anti-dsDNA), and complement components (C3, C4) were recorded. The correlations of MPVLR and PDWLR with disease activity and some laboratory parameters were analyzed.

Results

Lupus patients had significantly higher median (interquartile range) values for MPVLR and PDWLR than controls (5.69 [1.16-23.67] vs. 4.40 [2.78-11.93], p = 0.009) and 10.51 (2.87-79.37) vs. 5.21 (2.88-14.66), p < 0.001] respectively. According to the ROC curve, > 7.53 was the best PDWLR cut-off value for predicting SLE with a sensitivity of 71%, a specificity of 87% and an accuracy of 82.6%, whereas the optimum MPVLR cut-off value was > 6.46 with a sensitivity of 45.2%, a specificity of 88.9% and an accuracy of 76.8%. In addition, MPVLR had a significant positive correlation with SLEDAI (r = 0.34, p = 0.008). However, there was no significant correlation between PDWLR and SLEDAI (r = 0.23, p = 0.067). Furthermore, PDWLR had a significant positive correlation with PDW (r = 0.482, p < 0.001), while MPVLR had a significant negative correlation with C3 level (r = -0.260, p = 0.042). Both PDWLR and MPVLR were positively correlated with nephritis (r = 0.388, p = 0.002; r = 0.246, p = 0.038, respectively).

Conclusions

The platelet distribution width to lymphocyte ratio can be considered as an assisting biomarker in the diagnosis of SLE with the other clinical and serological parameters. The mean platelet volume to lymphocyte ratio may be used in the evaluation of disease activity in SLE patients.

Enrichment of complement, immunoglobulins and autoantibody targets in the proteome of platelets from patients with Systemic Lupus Erythematosus (SLE)

Background  Systemic lupus erythematosus (SLE) is a complex disease characterized by autoimmunity toward apoptotic cells, excessive amounts of circulating immune complexes, and complement activation. A decreased platelet size has been observed in SLE and their nonhemostatic functions may play an active role in the disease. The main objective of this study was to find clues that could explain their decreased size and functional role, analyzing the entire platelet proteome.

Methods  Platelets were isolated from 23 patients with SLE. The five individuals with the highest and lowest average platelet forward scatter were selected for further analysis. Platelet protein content was analyzed using liquid chromatography with tandem mass spectrometry (LC-MS/MS) and compared with platelets from five healthy controls. Data are available via ProteomeXchange with identifier PXD031202.

Results  Out of 2,572 proteins identified, 396 had significantly different levels (ANOVA q -value ≤ 0.01). Forty proteins, including immunoglobulin-, complement- and phosphatidylserine-binding proteins had higher abundance in platelets from SLE patients, largely independent of size (fold difference of ≥1.5 and a t -test p -value of ≤0.05 as cut-off). Functional characterization revealed increased degranulation and skewed hemostatic balance in platelets from SLE patients. In the SLE proteome, immunoglobulin proteins were negatively correlated to serum complement C3 and C4 and the highest relative levels were detected in platelets of normal size.

Conclusion  Platelets from SLE patients shared a specific protein profile, including immunoglobulins, complement proteins, and autoantigens, largely independent of the platelet size and in agreement with an integrated role for platelets in SLE.

Is mean platelet volume related to disease activity in systemic lupus erythematosus?

INTRODUCTION

Systemic lupus erythematosus (SLE) is a connective tissue disease that is chronic, recurrent and multisystem with unknown aetiology. There is still no single biomarker that is pathognomonic for the disease. We know that platelets are the main part of haemostasis and thrombosis. We aimed to investigate whether there is a connection between MPV with SLE and inflammatory markers.

MATERIAL AND METHODS

We have included 39 female patients with SLE and 45 controls in this study. In both groups, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP) levels and MPV levels were investigated. Clinical findings and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) were evaluated in patients.

RESULTS

There was no significant difference between the two groups in terms of demographic data. The MPV was 8.1 ± 0.5 (mean ± SD) in the patient's group and 7.6 ± 0.3 in the control group. There was a significant difference between the two groups in terms of MPV (P < .001). The ESR level was 30.7 ± 29 in the patient's group and 16.7 ± 10 in the control group. In the patient's group, the CRP levels were higher compared with that of the control group (8.2 ± 13, 4.5 ± 4, respectively). We found a statistically significant positive correlation between MPV with arthritis (r = .310,P = .004), nephritis (r = .446,P < .001), central nervous system involvement (r = .241,P = .027), vasculitis (r = .228,P = .037) and SLEDAI (r = .329,P = .002). In our study, we found increased levels of MPV in patients with SLE. Also, we observed a positive correlation among MPV with sedimentation, CRP, clinical manifestations and SLEDAI.

CONCLUSION

We consider that MPV may be a new activation indicator for the SLE.

Clinical Usefulness of Hematologic Indices as Predictive Parameters for Systemic Lupus Erythematosus

OBJECTIVE

This study assessed the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume, platelet distribution width, and red cell distribution width (RDW) in systemic lupus erythematosus (SLE) patients and their correlation with disease activity.

METHODS

Two hundred eight SLE patients and 205 age- and sex-matched healthy controls were included. Disease activity was assessed using the systemic lupus erythematosus disease activity index 2000, and hematological indices were determined.

RESULTS

Lymphocyte and platelet counts were significantly lower in SLE patients than in the controls, while the NLR, PLR, and RDW were significantly higher (P < .05). In patients with active disease, the neutrophil counts, NLR, and PLR were significantly higher than in those with inactive disease (P < .05), while the lymphocyte count was significantly lower (P < .05). Based on receiver operating characteristic curve analyses, only for lymphocyte count and PLR. The area under curve was significantly higher (P = .001 and P = .053, respectively).

CONCLUSION

PLR can serve as a biomarker for indicating SLE disease activity.

Low Intra-Individual Variation in Mean Platelet Volume Over Time in Systemic Lupus Erythematosus

Platelets have recently emerged as important immune modulators in systemic lupus erythematosus (SLE), in addition to their role in thrombosis and cardiovascular disease. However, studies investigating mean platelet volume (MPV) in SLE are often scarce, conflicting and cross-sectional. In this study, MPV was measured in clinical routine throughout a defined time-period to quantify both individual MPV fluctuations and investigate if such variations are associated with disease activity and clinical phenotypes of SLE. Of our 212 patients, 34 patients had only one MPV value reported with the remaining 178 patients having between 2 and 19 visits with recorded MPV values. The intra-individual MPV variation was low, with a median variation of 0.7 fL. This was further supported by the finding that 84% of patients stayed within their reference interval category (i.e., small, normal or large) over time. In our cohort, no correlation between disease activity and MPV neither cross-sectionally nor longitudinally was found. Mean platelet volume values were significantly smaller in SLE patients (mean 10.5 fL) compared to controls (mean 10.8 fL), p < 0.0001. Based on the reference interval, 2.4% (n = 5) of patients had large-sized platelets, 84.4% (n = 179) had normal-sized and 13.2% (n = 28) had small-sized. A larger proportion (85.7%) of patients with small-sized platelets met the anti-dsDNA criterion (ACR10b; p = 0.003) compared to patients with normal and large (57.6%) sized platelets. In conclusion, the intra-individual MPV variation was of low magnitude and fluctuations in disease activity did not have any significant impact on MPV longitudinally. This lack of variability in MPV over time indicates that measuring MPV at any time-point is sufficient. Further studies are warranted to evaluate MPV as a possible biomarker in SLE, as well as to determine the underlying mechanisms influencing platelet size in SLE.

Mean platelet volume in children with systemic lupus erythematosus

BACKGROUND

Platelets are heterogeneous in size, density, metabolic, functional, and biochemical properties. Mean platelet volume (MPV) is a measure of the average size of platelet in a blood sample.

AIM

We aimed to evaluate the mean platelet volume as a marker for disease activity in children with systemic lupus erythematosus.

MATERIALS AND METHODS

This was a prospective case-control study, which included 50 patients with SLE and 50 age and sex, matched healthy controls. All subjects were subjected to history taking, physical examination and laboratory parameters in active and remission phases of the diseases.

RESULTS

The MPV value in the SLE group was significantly higher than control group (9.6 ± 1.3 fL, 9.1 ± 0.57 fL, respectively, p = 0.04). There was a significant increase of weight, blood pressure, urea, creatinine, proteinuria, CRP, ESR, cholestrol, MPV values, SLEDAI-2K scores and significant decrease of HB, albumin, C3, mean platelet volume (MPC) in the active stage than in the remission stage. There was a significant negative correlation between MPV and MPC in active stage of the disease but the correlation was insignificant in remission stage.

CONCLUSION

MPV increased in active phase of patients with SLE and can be an easy, rapid, inexpensive and simple method to assess disease activity in children with SLE.

Serum Amyloid A: A Potential Biomarker Assessing Disease Activity in Systemic Lupus Erythematosus

Background

This study aimed to investigate the association between levels of serum amyloid A (SAA) and the activity of systemic lupus erythematosus (SLE).

Material/Methods

The study included 135 patients with SLE, including 52 patients with active SLE and 83 patients with inactive SLE and 149 healthy controls. The degree of activity of SLE was assessed using the SLE Disease Activity Index 2000 (SLEDAI-2K). Serum SAA levels were measured using a Cobas 8000 c702 modular analyzer.

Results

The levels of SAA were significantly increased in patients with active SLE compared with patients with inactive SLE (median IQR, 16.65 mg/L; range, 9.35–39.68 mg/L, and median IQR, 2.30 mg/L, range, 1.30–4.80 mg/L) (p<0.001). Levels of SAA were significantly correlated with the SLEDAI-2K scores, the erythrocyte sedimentation rate (ESR), and hypersensitive C-reactive protein (Hs-CRP) in patients with SLE (r=0.726, p<0.001; r=0.631, p<0.001; r=0.774, p<0.001, respectively). Multivariate logistic regression analysis showed that the SAA values were independently associated with active SLE when controlled for white blood cell (WBC) count, red blood cell distribution width (RDW), ESR, and Hs-CRP (OR=1.772; p=0.01; 95% CI, 1.101–2.851). Receiver operating characteristic (ROC) curve analysis for SAA was used to identify patients with active SLE with an area under the curve of 0.971, a sensitivity of 90.4%, and a specificity of 94.0%.

Conclusions

SAA levels were significantly correlated with disease activity in patients with SLE.

Mean platelet volume levels in children with sleep-disordered breathing: a meta-analysis

BACKGROUND

Pediatric sleep-disordered breathing (SDB) correlated with respiratory conditions of snoring and hypopnea. Mean platelet volume (MPV) was an inflammatory marker, related to increased inflammatory condition of pediatric patients. Increase of MPV level may cause failure to thrive or increased upper airway infection rate. The aim of this study was to perform systematic review and meta-analysis to investigate the difference on MPV values for pediatric SDB, and compare the change on MPV after surgery in patients with pediatric SDB.

METHODS

A systemic review of the studies from PubMed, EMBASE, and Cochrane Library databases was conducted in March 2020, supported by reviewing of published articles for studies comparing MPV in pediatric SDB. Meta-analysis was used to compare the change of MPV in pediatric SDB, and sub-group analysis was also used to compare the MPV decrease after surgeries of adenoidectomy or adenotonsillectomy.

RESULTS

There were seven studies included in the review. Six of them including 963 subjects showed that a significant increase of MPV was noted in pediatric SDB compared to those in pediatric non-SDB (P < 0.05). Total standardized mean difference (SMD) in MPV between pediatric SDB and non-SDB was 0.51 (95% CI =0.30-0.72, P < 0.05). A significant decrease of MPV was found in pediatric SDB patients who underwent surgery (total SMD = - 0.36; 95% CI = - 0.70- -0.02, P < 0.05). Decreases of MPV after adenoidectomy and adenotonsillectomy were observed, but only the effect of adenotonsillectomy had a statistical significance (total SMD = - 0.72; 95% CI = - 1.18 - -0.26, P < 0.05).

CONCLUSION

The MPV was significantly higher in patients with pediatric SDB, indicating the presence of increased platelet activity in pediatric SDB patients. The level of MPV could be reduced by the two surgeries, especially adenotonsillectomy.

Relation between mean platelet volume and C-reactive protein

Mean platelet volume (MPV) is a measure of platelet activation, and C-reactive protein (CRP) is an established marker of inflammation. Studies on the correlation between MPV and CRP have produced ambiguous results. We undertook a population study with the National Health and Nutrition Examination Survey (NHANES) data (2005-2010) to investigate the relationship between CRP and MPV. CRP was analyzed both as a continuous variable and as a categorical variable (low, intermediate, or high). Multivariate ordinary least squares regression analysis was used to predict the association. Statistical analyses were performed with Stata MP 15.1. In 16,329 participants, mean MPV was 7.9 fL (standard deviation 0.87). Overall mean CRP in the population was 0.4 mg/dL (standard deviation 0.78). In adjusted regression models with CRP as a continuous measure, individuals with high CRP had significantly lower MPV (b = -0.04; standard error 0.01; 95% confidence interval -0.06 to -0.01; P = 0.002). In adjusted regression models using CRP categories, participants with high CRP (>3 mg/dL) had significantly lower MPV compared with the low CRP group (b = -0.20; standard error 0.09; 95% confidence interval -0.38 to -0.01; P = 0.035). Our study revealed a significant inverse correlation between MPV and CRP in NHANES participants.