Cytokines affecting megakaryocytopoiesis in rheumatoid arthritis with thrombocytosis

Interleukin-10 in the Vasculature: Pathophysiological Implications

Interleukin-10 (IL-10) is an important immunomodulatory cytokine, initially characterized as an anti-inflammatory agent released by immune cells during infectious and inflammatory processes. IL-10 exhibits biological functions that extend to the regulation of different intracellular signaling pathways directly associated with vascular function. This cytokine plays a vital role in vascular tone regulation through the change of important proteins involved in vasoconstriction and vasodilation. Numerous investigations covered here have shown that therapeutic strategies inducing IL-10 result in anti-inflammatory, anti-hypertrophic, antihyperplastic, anti-apoptotic and antihypertensive effects. This non-systematic review summarizes the modulating effects mediated by IL-10 in vascular tissue, particularly on vascular tone, and the intracellular pathway induced by this cytokine. We also highlight the advances in IL-10 manipulation as a therapeutic target in different cardiovascular pathophysiologies, including the physiological implications in animals and humans. Finally, the review illustrates current and potential future perspectives of the potential use of IL-10 in clinical trials, based on the clinical evidence.

Systemic effects of IL-6 blockade in rheumatoid arthritis beyond the joints

Interleukin (IL)-6 is produced locally in response to an inflammatory stimulus, and is able to induce systemic manifestations at distance from the site of inflammation. Its unique signaling mechanism, including classical and trans-signaling pathways, leads to a major expansion in the number of cell types responding to IL-6. This pleiotropic cytokine is a key factor in the pathogenesis of rheumatoid arthritis (RA) and is involved in many extra-articular manifestations that accompany the disease. Thus, IL-6 blockade is associated with various biological effects beyond the joints. In this review, the systemic effects of IL-6 in RA comorbidities and the consequences of its blockade will be discussed, including anemia of chronic disease, cardiovascular risks, bone and muscle functions, and neuro-psychological manifestations.

Accelerated Spatial Fibrin Growth and Impaired Contraction of Blood Clots in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease associated with thrombotic complications. To elucidate pathogenic mechanisms, hemostatic disorders in RA were correlated with other laboratory and clinical manifestations. Hemostasis was assessed using relatively new complementary tests, the spatial growth of a plasma clot (Thrombodynamics assay), and contraction of whole blood clots. Platelet functionality was assessed with flow cytometry that quantified the expression of P-selectin and the fibrinogen-binding capacity of platelets before and after activation with a thrombin receptor-activating peptide. Parameters of fibrin clot growth and the kinetics of contraction of blood clots were significantly altered in patients with RA compared to the control group. In Thrombodynamics measurements, an increase in the clot growth rate, size, and optical density of plasma clots altogether indicated chronic hypercoagulability. The rate and extent of blood clot contraction in patients with RA was significantly reduced and associated with platelet dysfunction revealed by an impaired response to activation. Changes in the parameters of clot growth and contraction correlated with the laboratory signs of systemic inflammation, including hyperfibrinogenemia. These results confirm the pathogenic role of hemostatic disorders in RA and support the validity of fibrin clot growth and the blood clot contraction assay as indicators of a (pro)thrombotic state.

Cardiovascular Effects of Biologic Disease-Modifying Anti-Rheumatic Drugs (DMARDs)

The risk of cardiovascular (CV) disease is increased among patients with systemic autoimmune rheumatic diseases and remains an underserved area of medical need. Although traditional risk factors for CV disease, such as hypertension, smoking, dyslipidemia and obesity contribute to endothelial dysfunction in rheumatoid arthritis (RA), they are not enough on their own to explain the observed excess CV risk. Rather, systemic inflammation seems to play a pivotal role in both disease states. Considering the inflammatory process in autoimmune diseases, scientific interest has focused on recently introduced biologic disease-modifying agents (bDMARDS) such as inhibitors of Tumor Necrosis Factor- α (ΤΝF-α), Interleukins -1 (IL-1) and -6 (IL-6). Despite the widespread use of bDMARDS in RA and other chronic autoimmune inflammatory diseases, their precise impact on CV disease and outcome remains to be elucidated, while prospective randomized control trials assessing their impact on hard CV endpoints are scarce. In this review, we summarize current knowledge concerning the effect of bDMARDs on CV outcome and on the risk of developing CV disease in patients with systemic autoimmune rheumatic diseases.

Blood mean platelet volume and platelet lymphocyte ratio as new predictors of hip osteoarthritis severity

Osteoarthritis (OA) is a low grade systemic inflammatory disease in which many inflammatory mediators are known to be elevated in the peripheric blood. Blood platelet lymphocyte ratio (PLR) and mean platelet volume (MPV) are accepted as novel markers in many of the systemic inflammatory disorders, but have not been investigated in synovitis-free radiographic OA yet.The aim of this study was to evaluate the levels of blood PLR and MPV in radiographic hip OA. A total of 880 patients were evaluated retrospectively and after certain exclusion criteria, 237 of them who have primary hip OA were included. Age, sex, height, weight, body mass index, neutrophil, lymphocyte and platelet counts, erythrocyte sedimentation rate (ESR), PLR, and MPV levels were recorded, Kellgren-Lawrence (KL) grading of the hip joints were performed. Patients were then divided into 2 groups as KL grades 1 to 2 (mild-moderate) and KL grades 3 to 4 (severe) hip OA.Mean age, mean neutrophil, lymphocyte and platelet counts, mean MPV, mean PLR, and mean ESR were statistically significantly different between mild/moderate hip OA group and severe hip OA group. In univariate analysis, older age and higher MPV, PLR, and ESR were severely associated with severe hip OA. In multiple logistic regression analysis, MPV, PLR, and ESR emerged as independent predictors of severe hip OA.The results of the present study, for the first time in the literature, suggest blood PLR and MPV as novel inflammatory markers predicting the radiographic severity of hip OA in the daily practice.

A Study on Association between Common Haematological Parameters and Disease Activity in Rheumatoid Arthritis

INTRODUCTION

Rheumatoid Arthritis (RA) is a chronic systemic inflammatory disease where assessment of disease activity is essential for management of patient. Currently, many composite scoring systems are used for evaluation of disease activity but they are mainly clinical-based. As several haematological parameters are altered due to systemic inflammatory process in RA, this study was intended to evaluate role of common haematological parameters to assess disease activity in RA.

AIM

To find out the association of disease activity of Rheumatoid Arthritis (RA) with platelet count, Mean Platelet Volume (MPV) and Haemoglobin (Hb) level so that these cost-effective haematological parameters can be used as additional factors to assess disease activity.

MATERIALS AND METHODS

This hospital based cross-sectional study was done on newly diagnosed patients of RA along with age and sex matched healthy control population. Patients suffering from malignancies, renal failure, diabetes mellitus or RA patients on drug therapy were excluded. Clinically, disease activity of RA was measured using DAS 28-3 Score (Modified Disease Activity Score using three variables- tender joint count, swollen joint count and ESR). Haematological parameters were measured by automated cell counter.

RESULTS

Total 80 cases were selected (60 female and 20 male). 48 patients with high disease activity (DAS 28-3>5.1) were labelled as Group-A and 32 with low to moderate disease activity (DAS 28-3 ≤5.1) as Group- B. Mean platelet count of patients of group A and group B were 4.53 lac/cmm and 2.17 lac/cmm respectively (p <0.001). MPV mean in group A and B were 11.86 fl and 10.19 fl respectively (p <0.001). Mean Hb (g/dl) was 10.05 and 12.25 for group A and B respectively (p=0.001) for male patients while in females it was 10.12 and 11.91 for group A and B, respectively (p=0.003). Mean platelet count and MPV in control population were 2.07 lac/cmm and 9.4 fl, respectively while mean Hb (g/dl) was 13.31 (male) and 12.01 (female).

CONCLUSION

In our study it was observed that Hb is significantly lower in patients with high disease activity whereas platelet count and MPV are significantly higher with high disease activity compared to patients with low to moderate disease activity.

Chronic arthritis and cardiovascular disease: altered blood parameters give rise to a prothrombotic propensity

OBJECTIVE

Rheumatoid arthritis, and to a lesser extent ankylosing spondylitis and psoriatic arthritis, associates with increased morbidity and mortality due to cardiovascular complications. We hypothesized that the increased risk of cardiovascular disease is reflected by changes in blood parameters that are compatible with a prothrombotic propensity. To substantiate this notion, we performed an extensive literature search identifying such parameters.

METHODS

A search through PubMed (1970-2013) was done to find primary articles with the following search terms: rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis or synovial fluid. These were combined with keywords reflecting processes of atherothrombosis: atherosclerosis, cardiovascular disease, coagulation, endothelial, fibrinolysis, mean platelet volume, microparticle, platelet, platelet count and mass, thrombosis, and thrombus.

RESULTS

The published studies point to a multitude of blood-related processes that can contribute to a prothrombotic propensity in chronic inflammatory diseases. These include an increase in platelet mass; low-level platelet activation, enforced by interaction with leukocytes and the formation of proinflammatory cytokines; a locally activated endothelium; and an increased coagulant activity. Patient treatment with methotrexate or TNF-α blockers appears to result in normalization of several of these prothrombotic parameters.

CONCLUSION

This analysis provides a first identification of the mechanisms by which inflammatory arthritis can aggravate cardiovascular disease.

Response to traditional disease-modifying anti-rheumatic drugs in indigent South Africans with early rheumatoid arthritis

The clinical response to traditional disease-modifying anti-rheumatic drugs (DMARDs) in indigent South Africans with early rheumatoid arthritis was investigated. A cohort of patients with early (≤2 years) RA who were DMARD-naïve at inception were prospectively assessed for response to DMARDs using the Simplified Disease Activity Index (SDAI) over a 12-month period. Patients with low disease activity (LDA) at 12 months were compared to those with moderate and high disease activity with respect to demographic, clinical, autoantibody and radiographic features. The 171 patients (140 females) had a mean (SD) age of 47.1 (12.4) years, symptom duration of 11.7 (7.1) months and baseline SDAI of 39.4 (16.2). There was a significant overall improvement in the SDAI and its components in the 134 (78.4%) patients who completed the 12 months visit, but only 28.4% of them achieved LDA. The majority of patients (91%) were treated with methotrexate as monotherapy or in combination with chloroquine and/or sulphasalazine. Baseline features that independently predicted a LDA state at 12 months were lower Health Assessment Questionnaire Disability Index (p = 0.023) and a higher haemoglobin level (p = 0.048). Receiver operating characteristic curve analysis showed that the 6-month SDAI was better than the baseline SDAI in predicting the 12-month SDAI (area under the curve of 0.69 vs. 0.52, respectively, p = 0.008). In conclusion, less than a third of the patients achieved a low disease activity at 12 months on traditional DMARDs. Patients who have an inadequate response to traditional DMARDs at 6 months are unlikely to show further improvement on traditional DMARDs at 12 months. These findings underscore the need for better disease control by an aggressive tight control strategy, including intense patient education and biologic therapy.

The effect of desmopressin on blood loss in patients with rheumatoid arthritis undergoing hip arthroplasty

BACKGROUND

Blood loss is an important issue for patients with rheumatoid arthritis undergoing hip surgery. We hypothesised that intraoperative desmopressin treatment would result in a reduction in blood loss in rheumatoid patients undergoing total hip arthroplasty.

METHODS

Seventy-five patients scheduled for elective total hip arthroplasty were randomised to three groups to receive 0.4 microg/kg desmopressin (D 0.4), 0.2 microg/kg desmopressin (D 0.2) or placebo intraoperatively in a double-blind fashion. Blood transfusions were based on calculated safe allowable blood loss and haemoglobin measurements (trigger 90 g/l, 5.59 mmol/l). The primary endpoint was the total blood loss measured till the end of the fourth post-operative day. Secondary endpoints included red cell transfusion requirements and haemoglobin.

RESULTS

Total blood loss during the study period was not significantly different between the groups (D 0.4 1829 +/- 1068; D 0.2 2240 +/- 843 and placebo 2254 +/- 1040 ml; P= 0.50). The total amount of red cell transfusions was fewer in group D 0.4 (3.6 +/- 1.6 U) when compared with D 0.2 (4.4 +/- 1.7 U; P=0.009) and placebo (4.5 +/- 2.0 U; P= 0.011) groups. Haemoglobin concentration was lower in the placebo group in the first (5.42 +/- 1.16 vs. 5.98 +/- 0.47 mmol/l; P=0.033) and the second (6.28 +/- 0.66 vs. 6.69 +/- 0.47 mmol/l; P=0.033) post-operative mornings compared with group D 0.4.

CONCLUSION

Despite a lack of difference in the primary outcome, total blood loss, intraoperative administration of 0.4 microg/kg desmopressin resulted in fewer total red cell transfusion requirements in rheumatoid patients undergoing total hip arthroplasty when compared with 0.2 microg/kg treatment and placebo.

Differing effect of systemic anti psoriasis therapies on platelet physiology--a case report and review of literature

BACKGROUND

Psoriasis is a common, chronic relapsing inflammatory skin disease. Lately, there is increasing evidence that psoriasis is more than "skin deep". Epidemiological studies showed that severe psoriasis might have also important systemic manifestations such as metabolic deregulations, cardiovascular disease (CVD) and increased mortality. Moreover, recently psoriasis patients were found to have platelet hyperactivity.

CASE PRESENTATION

This is a case report and review of the literature. We present a patient with long standing severe psoriasis vulgaris with marked thrombocytosis. His thrombocytosis did not correlate with disease severity but rather with the different treatments that he was exposed to, subsiding only during treatment with anti Tumor Necrosis Factor (TNF)- agents. A literature review revealed that in rheumatoid arthritis, another systemic inflammatory disease; interleukin (IL)-6 might be implicated in causing thrombocytosis.

CONCLUSION

This unique case report illustrates that different systemic treatments for psoriasis might have implications beyond the care of skin lesions. This insight is especially important in psoriasis patients in view of their deranged hemostatic balance toward a prothrombotic state, which might increase the risk of thrombosis and CVD. Therefore, further studies analyzing the effect of different drugs on platelets physiology are warranted.

Reactive thrombocytosis: an early manifestation of Takayasu arteritis

A woman with Takayasu arteritis is reported who presented with constitutional symptoms and persistent thrombocytosis documented since 3 years before the diagnosis. Disease-specific symptoms such as arm claudication, transient loss of vision, and self-remitting eye ptosis present at the time were apparently missed, because she is a non-English-speaking Hispanic woman whose history was obtained through an interpreter. Extensive workup done at the time failed to reach a definite etiology. A computed tomography scan of the chest done because of midthoracic back pain and an elevated erythrocyte sedimentation rate showed circumferential wall thickening and mild surrounding edema throughout the thoracic and abdominal aorta and both carotid arteries consistent with Takayasu arteritis. Prednisone at a dosage of 1 mg/kg twice a day decreased the platelet count within 45 days of its initiation. Takayasu arteritis should be considered in the differential diagnosis of unexplained thrombocytosis, particularly in young women.

Pathologic thrombopoiesis of rheumatoid arthritis

Rheumatoid arthritis (RA) is frequently complicated by thrombocytosis correlated with disease activity. The exact pathogenetic mechanism(s) that cause increased platelet counts in RA are still unknown. Recent investigations indicate that proinflammatory pleiotropic cytokines of RA also have megakaryocytopoietic/thrombopoietic properties. Moreover, several lineage-dominant hematopoietic cytokines can also act as acute phase responders and contribute to the inflammation. This review focuses on the current literature and our experience regarding the dual relationships of the pathologic thrombopoiesis of RA. Growth factors contributing to it, namely interleukin (IL)-6, IL-11, stem cell factor, leukemia inhibitory factor, granulocyte colony stimulating factor, thrombopoietin (TPO), and the regulation of megakaryocytopoiesis during the inflammatory cascade are reviewed. Some data indicate that thrombopoietin could contribute to the reactive thrombocytosis of RA. In the non-lineage-specific gp130 cytokine family, IL-6 appears to predominate for the induction of megakaryopoiesis. However, other cytokines and growth factors may also contribute to the pathologic megakaryocytopoiesis of RA. Those pleiotropic mediators seem to act in concert to regulate this enigmatic process. Clarification of the pathobiologic basis of thrombopoiesis in RA may improve understanding of the disease pathogenesis and management of the inflammatory thrombocytosis.

Assessment of platelet numbers and morphology in the peripheral blood smear

Automated systems are currently in widespread use for the assessment of patients' complete blood counts. The evaluation of the peripheral blood smear, however, still constitutes a pivotal tool in the evaluation of patients with hematologic disorders. This article focuses on disorders affecting the number or morphology of platelets as assessed by evaluation of a peripheral blood smear and also outlines some of their important clinical findings.

A combination of megakaryocyte growth and development factor and interleukin-1 is sufficient to culture large numbers of megakaryocytic progenitors and megakaryocytes for transfusion purposes

Chemotherapy-induced thrombocytopenia is a major risk factor in cancer treatment. The transfusion of autologous ex vivo expanded megakaryocytes could be a new therapy to shorten the period of thrombocytopenia. Therefore we investigated, in a liquid culture system, the effect of various cytokine combinations composed of pegylated megakaryocyte growth and development factor (PEG-rHuMGDF), interleukin-1 (IL-1), IL-3, IL-6, IL-11 and stem cell factor (SCF) on the proliferation and differentiation of CD34+ cells, in order to define the most optimal and minimum levels of cytokine combinations for megakaryocyte expansion. Besides PEG-rHuMGDF, IL-1 was found to be important for optimal megakaryocyte expansion. Depletion of either SCF, IL-6 or IL-11 did not exert a large effect, but the absence of IL-1 strongly diminished the number of megakaryocytic cells. Addition of IL-3 to the combination PEG-rHuMGDF, IL-1, IL-6, IL-11 and SCF significantly reduced the number of megakaryocyte progenitors (CD34+CD41+ cells) and the number of CFU-Meg. Furthermore, we found a strong correlation between the number of CD34+CD41+ cells and the number of CFU-Meg obtained after 8 d culture. Our study shows that optimal ex vivo expansion of megakaryocytes is achieved by the combination of PEG-rHuMGDF and IL-1. The numbers of megakaryocytes and megakaryocyte progenitors (CD34+CD41+) obtained in our liquid culture system with the growth factor combination PEG-rHuMGDF and IL-1 are suitable for transfusion purposes.