Mean Platelet Volume (MPV) as an indicator of disease activity and severity in lupus

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.

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.

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.

Recent Updates and Advances in Winiwarter-Buerger Disease (Thromboangiitis Obliterans): Biomolecular Mechanisms, Diagnostics and Clinical Consequences

Thromboangiitis obliterans (TAO) or Buerger’s disease is a segmental inflammatory, thrombotic occlusive peripheral vascular disease with unknown aetiology that usually involves the medium and small-sized vessels of young male smokers. Due to its unknown aetiology and similarities with atherosclerosis and vasculitis, TAO diagnosis is still challenging. We aimed to review the status of biomolecular and laboratory para-clinical markers in TAO compared to atherosclerosis and vasculitis. We reported that, although some biomarkers might be common in TAO, atherosclerosis, and vasculitis, each disease occurs through a different pathway and, to our knowledge, there is no specific and definitive marker for differentiating TAO from atherosclerosis or vasculitis. Our review highlighted that pro-inflammatory and cell-mediated immunity cytokines, IL-33, HMGB1, neopterin, MMPs, ICAM1, complement components, fibrinogen, oxidative stress, NO levels, eNOS polymorphism, adrenalin and noradrenalin, lead, cadmium, and homocysteine are common markers. Nitric oxide, MPV, TLRs, MDA, ox-LDL, sST2, antioxidant system, autoantibodies, and type of infection are differential markers, whereas platelet and leukocyte count, haemoglobin, lipid profile, CRP, ESR, FBS, creatinine, d-dimer, hypercoagulation activity, as well as protein C and S are controversial markers. Finally, our study proposed diagnostic panels for laboratory differential diagnosis to be considered at first and in more advanced stages.

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.

Clinical relevance of neutrophil-to-lymphocyte ratio and mean platelet volume in pediatric Henoch-Schonlein Purpura: a meta-analysis

The association of neutrophil-to-lymphocyte ratio (NLR) and mean platelet volume (MPV) with the severe gastrointestinal (GI) involvement in pediatric Henoch–Schonlein Purpura (HSP) has been reported in many studies. However, the conclusions from the previous studies were controversial. Therefore, for the first time, we performed a meta-analysis to systematically evaluate the relationship of NLR and MPV to the severe GI involvements. We retrieved PubMed, EMBASE, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) (up to October 2020) thoroughly to acquire eligible studies. The pooled standard mean difference (SMD) with 95% confidence interval (CI) was used to describe the correlation of NLR and MPV with the severe GI involvement. A total of 1² studies comprising 2168 patients with HSP were included in this meta-analysis. Our combined analysis showed that NLR in HSP patients with the severe GI involvement was significantly higher than that in those without the severe GI involvement (SMD = 1.37; 95% CI: 0.70–2.05; p < 0.01). In addition, a lower MPV was observed in children with severe GI involvement (SMD = −0.29; 95% CI: −0.56 – −0.01, p = 0.042). Our sensitivity analysis and publication bias evaluation indicated that our combined results were reliable. Taken together, our study suggested NLR and MPV may be used as biomarkers for predicting or diagnosing the severe GI involvement in children with HSP. Nevertheless, more homogeneous studies with a larger sample size are required to validate these findings.

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.

Platelets in Skin Autoimmune Diseases

Systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and small vessel vasculitis are three autoimmune diseases frequently manifested in the skin. They share common pathogenic features, including production of autoantibodies, loss of tolerance to self-antigens, tissue necrosis and fibrosis, vasculopathy and activation of the coagulation system. Platelets occupy a central part within the coagulation cascade and are well-recognized for their hemostatic role. However, recent cumulative evidence implicates their additional and multifaceted immunoregulatory functions. Platelets express immune receptors and they store growth factors, cytokines, and chemokines in their granules enabling a significant contribution to inflammation. A plethora of activating triggers such as damage associated molecular patterns (DAMPs) released from damaged endothelial cells, immune complexes, or complement effector molecules can mediate platelet activation. Activated platelets further foster an inflammatory environment and the crosstalk with the endothelium and leukocytes by the release of immunoactive molecules and microparticles. Further insight into the pathogenic implications of platelet activation will pave the way for new therapeutic strategies targeting autoimmune diseases. In this review, we discuss the inflammatory functions of platelets and their mechanistic contribution to the pathophysiology of SSc, ANCA associated small vessel vasculitis and other autoimmune diseases affecting the skin.

Altered mean platelet volume in children with Henoch-Schonlein purpura and its association with disease activity

Background

Henoch-Schonlein purpura is a systemic small-vessel vasculitis that occurs mainly in children. A review of the literature has suggested a correlation between mean platelet volume and several inflammatory disorders. However, to the best of our knowledge, any potential correlation between mean platelet volume and Henoch-Schonlein purpura has not been reported in the literature. Therefore, our study aimed to evaluate the role of mean platelet volume concentrations in patients with Henoch-Schonlein purpura.

Methods

This study included 97 children with Henoch-Schonlein purpura and 120 healthy individuals as controls.

Results

Mean platelet volume concentrations were found to be significantly lower in Henoch-Schonlein purpura patients compared with healthy controls (8.1 ± 0.86 vs. 9.4 ± 0.81, P < 0.001). Similarly, significant negative correlations were observed between mean platelet volume and neutrophil count, platelet count and erythrocyte sedimentation rate in patients with Henoch-Schonlein purpura (r=−0.327, P = 0.001; r=−0.419, P < 0.001; r=−0.255, P = 0.012). Interestingly, mean platelet volume was significantly lower in the acute phase compared with the convalescent phase of Henoch-Schonlein purpura patients (7.8 ± 0.86 vs. 8.3 ± 0.77, P = 0.002). A cut-off value for mean platelet volume was 7.85 with area under the curve of 0.726 to identify acute phase vs. convalescent phase in patients with Henoch-Schonlein purpura. Mean platelet volume was independently associated with Henoch-Schonlein purpura in logistic regression analysis (odds ratio = 0.114, 95% confidence interval = 0.053–0.243, P < 0.001).

Conclusions

Our results suggest that mean platelet volume is inversely associated with disease in patients with Henoch-Schonlein purpura, and mean platelet volume may be a useful marker to identify active disease in Henoch-Schonlein purpura patients.