Pathologic thrombopoiesis of rheumatoid arthritis

Mitochondrial Oxidative Stress Related Diagnostic Model Accurately Assesses Rheumatoid Arthritis Risk Stratification and Immune Infiltration Characterization

Rheumatoid arthritis (RA) is a chronic autoimmune disease that affects synovial joints, leading to joint destruction, impaired physical function, and reduced quality of life. However, no accurate method for assessing RA risk currently exists. Given the critical role of early detection and intervention in RA management, further comprehensive risk assessments are essential. Mitochondrial oxidative stress (MOS) is a key factor in the initiation and progression of RA. The bidirectional interaction between RA and MOS supports the feasibility of MOS-based risk stratification for RA. Using public databases, we first applied the weighted gene co-expression network analysis (WGCNA) model to identify key genes involved in RA among MOS-related genes. Differential expression patterns of MOS-related genes were then analyzed using various machine learning algorithms to identify potential biomarkers. A nomogram model was established using CDKN1A, GADD45B, and MAFF genes to predict RA risk, followed by an evaluation of its reliability and stability. Additionally, we analyzed MOS-associated molecular subtypes and immune infiltration characteristics. Our findings highlight the significant role of MOS in RA development and underscore the clinical value of personalized treatment strategies.

Identifying antinuclear antibody positive individuals at risk for developing systemic autoimmune disease: development and validation of a real-time risk model

Objective

Positive antinuclear antibodies (ANAs) cause diagnostic dilemmas for clinicians. Currently, no tools exist to help clinicians interpret the significance of a positive ANA in individuals without diagnosed autoimmune diseases. We developed and validated a risk model to predict risk of developing autoimmune disease in positive ANA individuals.

Methods

Using a de-identified electronic health record (EHR), we randomly chart reviewed 2,000 positive ANA individuals to determine if a systemic autoimmune disease was diagnosed by a rheumatologist. A priori, we considered demographics, billing codes for autoimmune disease-related symptoms, and laboratory values as variables for the risk model. We performed logistic regression and machine learning models using training and validation samples.

Results

We assembled training (n = 1030) and validation (n = 449) sets. Positive ANA individuals who were younger, female, had a higher titer ANA, higher platelet count, disease-specific autoantibodies, and more billing codes related to symptoms of autoimmune diseases were all more likely to develop autoimmune diseases. The most important variables included having a disease-specific autoantibody, number of billing codes for autoimmune disease-related symptoms, and platelet count. In the logistic regression model, AUC was 0.83 (95% CI 0.79-0.86) in the training set and 0.75 (95% CI 0.68-0.81) in the validation set.

Conclusion

We developed and validated a risk model that predicts risk for developing systemic autoimmune diseases and can be deployed easily within the EHR. The model can risk stratify positive ANA individuals to ensure high-risk individuals receive urgent rheumatology referrals while reassuring low-risk individuals and reducing unnecessary referrals.

Mean Platelet Volume in a Series of 315 Patients with Rheumatoid Arthritis: Relationship with Disease Characteristics, including Subclinical Atherosclerosis and Cardiovascular Comorbidity

Mean platelet volume (MPV) refers to the average platelet size in femtoliters. Increased or decreased MPV has been associated with several disorders, including inflammatory and cardiovascular diseases. In the present study, our objective was to analyze the relationship of MPV with disease activity in a large and well-characterized series of patients with rheumatoid arthritis (RA). This is a cross-sectional study that included 315 patients with RA and 208 controls matched by sex and age. Complete blood count, including MPV, was assessed. Multivariable analysis was performed to examine the relationship of MPV with RA disease characteristics, carotid atherosclerosis, and traditional cardiovascular factors, including a comprehensive profile of lipid molecules and insulin resistance or beta cell function indices. The multivariable analysis, which includes other hematological modifications produced by the disease and platelet values, showed that MPV levels were significantly lower in RA patients than in controls. Erythrocyte sedimentation rate and interleukin-6, but not C-reactive protein, were negatively correlated with MPV after adjustment for covariates. Similarly, disease activity and MPV had a significant and independent negative correlation. No relationships were found between MPV and cardiovascular risk factors, lipid profile or insulin resistance indices or subclinical atherosclerosis. In conclusion, patients with RA have lower levels of MPV than controls. MPV is negatively related to acute phase reactants and disease activity in RA.

Clinical prediction rule for bacterial arthritis: Chi-squared automatic interaction detector decision tree analysis model

Objectives:

Differences in demographic factors, symptoms, and laboratory data between bacterial and non-bacterial arthritis have not been defined. We aimed to identify predictors of bacterial arthritis, excluding synovial testing.

Methods:

This retrospective cross-sectional survey was performed at a university hospital. All patients included received arthrocentesis from January 1, 2010, to December 31, 2020. Clinical information was gathered from medical charts from the time of synovial fluid sample collection. Factors potentially predictive of bacterial arthritis were analyzed using the Student’s t-test or chi-squared test, and the chi-squared automatic interaction detector decision tree analysis. The resulting subgroups were divided into three groups according to the risk of bacterial arthritis: low-risk, intermediate-risk, or high-risk groups.

Results:

A total of 460 patients (male/female = 229/231; mean ± standard deviation age, 70.26 ± 17.66 years) were included, of whom 68 patients (14.8%) had bacterial arthritis. The chi-squared automatic interaction detector decision tree analysis revealed that patients with C-reactive protein > 21.09 mg/dL (incidence of septic arthritis: 48.7%) and C-reactive protein ⩽ 21.09 mg/dL plus 27.70 < platelet count ⩽ 30.70 × 10⁴/μL (incidence: 36.1%) were high-risk groups.

Conclusions:

Our results emphasize that patients categorized as high risk of bacterial arthritis, and appropriate treatment could be initiated as soon as possible.

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.

Is It Possible to Predict Clonal Thrombocytosis in Triple-Negative Patients with Isolated Thrombocytosis Based Only on Clinical or Blood Findings?

JAK2, MPL, and CALR mutations define clonal thrombocytosis in about 90% of patients with sustained isolated thrombocytosis. In the remainder of patients (triple-negative patients) diagnosing clonal thrombocytosis is especially difficult due to the different underlying conditions and possible inconclusive bone marrow biopsy results. The ability to predict patients with sustained isolated thrombocytosis with a potential clonal origin has a prognostic value and warrants further examination. The aim of our study was to define a non-invasive clinical or blood parameter that could help predict clonal thrombocytosis in triple-negative patients. We studied 237 JAK2 V617-negative patients who were diagnosed with isolated thrombocytosis and referred to the haematology service. Sixteen routine clinical and blood parameters were included in the logistic regression model which was used to predict the type of thrombocytosis (reactive/clonal). Platelet count and lactate dehydrogenase (LDH) were the only statistically significant predictors of clonal thrombocytosis. The platelet count threshold for the most accurate prediction of clonal or reactive thrombocytosis was 449 × 10⁹/L. Other tested clinical and blood parameters were not statistically significant predictors of clonal thrombocytosis. The level of LDH was significantly higher in CALR-positive patients compared to CALR-negative patients. We did not identify any new clinical or blood parameters that could distinguish clonal from reactive thrombocytosis. When diagnosing clonal thrombocytosis triple-negative patients are most likely to be misdiagnosed. Treatment in patients with suspected triple negative clonal thrombocytosis should not be delayed if cardiovascular risk factors or pregnancy coexist, even in the absence of firm diagnostic criteria. In those cases the approach “better treat more than less” should be followed.

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.

The role of mean platelet volume in patients with Takayasu arteritis

Background Takayasu arteritis is a chronic non-specific inflammatory disease and mean platelet volume can either be decreased or increased during inflammation. However, there are no published data to confirm an association between mean platelet volume and Takayasu arteritis. Our aim was to evaluate the role of mean platelet volume in patients with Takayasu arteritis. Methods A total of 119 consecutive patients with Takayasu arteritis and 217 healthy individuals were included in this study. Forty-five Takayasu arteritis patients with active disease were followed with prednisone therapy. Results Mean platelet volume of patients was low compared with control groups (10.1 ± 1.47 fL vs. 11.2 ± 0.91 fL; P < 0.001). Mean platelet volume was lower in active Takayasu arteritis than in inactive Takayasu arteritis patients (9.3 ± 1.39 fL vs. 10.6 ± 1.28 fL; P< 0.001). Mean platelet volume values were significantly increased after prednisone treatment (9.3 ± 1.45 fL vs. 10.5 ± 1.29 fL; P < 0.001). Mean platelet volume negatively correlated with C-reactive protein, erythrocyte sedimentation rate, neutrophil count and platelet count (r = - 0.219, P = 0.018; r = - 0.296, P < 0.001; r = - 0.273, P = 0.003; r =-0.486, P< 0.001), and positively correlated with platelet distribution width (r=0.304, P ≤ 0.001) in patients with Takayasu arteritis. An inverse correlation between mean platelet volume and erythrocyte sedimentation rate was observed in active Takayasu arteritis patients (r = -0.406, P = 0.010). In multiple linear regression analysis, mean platelet volume was independently correlated with erythrocyte sedimentation rate in patients with Takayasu arteritis. Conclusions Our results suggest that mean platelet volume may identify active disease in patients with Takayasu arteritis, and the values of mean platelet volume may help to establish remission of active disease after treatment in Takayasu arteritis patients.

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.

Changes of Platelet Indices in Juvenile Idiopathic Arthritis in Acute Phase and After Two Months Treatment

BACKGROUND

Various indices have been raised as predictors of activity and severity of juvenile idiopathic arthritis.

OBJECTIVES

This study was conducted to investigate the changes of platelet indices in acute phase and two months after treatment in these patients.

PATIENTS AND METHODS

In a cohort study, platelet count, mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT) were evaluated in children referred to children's medical center, Tehran due to juvenile idiopathic arthritis from March 2013 to March 2014 during the acute phase and two months after standard treatment. The statistical data were analyzed by SPSS 19 software, and the significance level was set as P < 0.05.

RESULTS

In this study, 55 children (24 boys and 31 girls) with mean ± SD age of 7.50 ± 3.35 years were studied. The mean ± SD value of platelet count was 441872.7 ± 151836.9 in the acute phase and reached 395418.2 ± 119601.6 two months after treatment (P = 0.01). The mean ± SD PCT in the acute phase of various subtypes of the disease was 0.32 ± 0.11, which reached 0.29 ± 0.10 after treatment (P = 0.09). However, the PDW range in different subtypes of the disease reached 13.4 ± 8.0 from 13.9 ± 2.9 and MPV reached 8.7 ± 0.9 from 8.8 ± 1.1 after treatment, but they were not significantly different from the results in the acute phase (P = 0.5).

CONCLUSIONS

Platelet count is one of the most remarkable indices in JIA. Evaluation of PCT can also help determine the severity of the inflammatory process in the follow-up and treatment process.

Mean platelet volume, red cell distribution width, platelet-to-lymphocyte and neutrophil-to-lymphocyte ratios in patients with ankylosing spondylitis and their relationships with high-frequency hearing thresholds

The mean platelet volume (MPV), red cell distribution width (RDW) and neutrophil-to-lymphocyte ratio (NLR) comprise laboratory markers in ankylosing spondylitis (AS). There is a controversy in the literature regarding which type of ear involvement is characteristic of AS. The aim of this study was to simultaneously investigate the MPV, RDW, platelet to lymphocyte (PLR) and NLR in patients with AS and their relationships with high-frequency hearing thresholds. Thirty patients with AS and 35 age-matched healthy subjects were included. Each subject was tested with low- (250, 500, 1000 and 2000 Hz) and high- (4000, 8000, 10,000, 12,000, 14,000 and 16,000 Hz) frequency audiometry. Additionally, the case and control groups were evaluated regarding the average hearing thresholds in bone conduction. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels were measured. The RDW, MPV, neutrophils, lymphocytes and platelet counts were evaluated with the complete blood count. Furthermore, the NLR and PLR were calculated. The complete blood count, platelet numbers, ESR, CRP and NLR levels were significantly increased in the AS patients compared with the healthy controls (p < 0.001, p = 0.007, p < 0.001, p < 0.001 and p = 0.047, respectively). There was no statistically significant difference in the RDW, PLR or MPV levels (p > 0.05) in the AS patients compared with the healthy controls. The BASDAI score and disease duration were not correlated with the ESR, CRP levels, MPV, PLR, RDW or NLR in patients with AS (all; p > 0.05). The AS patients had increased average measurement values for the hearing threshold in both ears at frequencies of 250, 500, 1000 and 2000 Hz; however, there was no statistically significant difference (p > 0.05). The average values of the hearing threshold in both ears at the high frequencies of 4000, 6000, 8000, 10,000, 12,000 and 14,000 Hz were significantly increased in the case group; however, it was not significantly increased at 16,000 Hz. The current study is the first to investigate the PLR, NLR, MPV and RDW levels in acute AS. We identified a significantly increased NLR, leukocyte count, ESR and CRP in AS patients. Sensorineural hearing loss, especially at extended high frequencies, is common in patients with AS and may represent an extra-articular feature of the disease. The combined use of NLR with the leukocyte count and other clinical assessments may facilitate the diagnostic process of ankylosing spondylitis.

Early growth response-1 (EGR-1) and nuclear factor of activated T cells (NFAT) cooperate to mediate CD40L expression in megakaryocytes and platelets

Increasing evidence implicates circulating platelets as mediators of chronic inflammatory and autoimmune diseases via the expression and release of CD40L, an important modulator of inflammation and adaptive immune responses traditionally associated with activated T cells. Emerging evidence suggests that platelet CD40L is dynamically regulated in several chronic inflammatory and autoimmune diseases and may mediate progression and secondary pathology associated with those disease states. The present study identifies NFATc2 as a key transcriptional modulator of CD40L expression in megakaryocytes and inflammatory activity of platelets. Furthermore, the current data show that EGR-1, a member of the early growth response family of zinc finger transcription factors, modulates NFATc2-dependent regulation of CD40L expression in megakaryocytes. Our novel demonstration that in vivo biochemical or genetic inhibition of NFATc2 activity in megakaryocyte diminishes platelet CD40L implicates the NFATc2/EGR-1 axis as a key regulatory pathway of inflammatory and immunomodulatory activity in platelets and represents a target for the development of therapeutics for the potential treatment of chronic inflammatory and autoimmune diseases.

The predictive value of mean platelet volume in differential diagnosis of non-functional pancreatic neuroendocrine tumors from pancreatic adenocarcinomas

OBJECTIVE

The aim of the present study is to evaluate in a retrospective manner the diagnostic value of mean platelet volume (MPV) in pancreatic adenocarcinomas and pancreatic neuroendocrine tumors (PNETs).

PATIENTS AND METHODS

A total of 92 patients, who were admitted for pancreatic adenocarcinoma (n=76) and PNET (n=16) between March 2007 and December 2009, were analyzed retrospectively for demographics and clinical information.

RESULTS

Thirty-nine patients (51.3%) had a resectable, whereas 37 patients (48.7%) had an unresectable pancreatic adenocarcinoma. Nine patients (56.3%) had a non-functional PNET, 6 patients (37.5%) had an insulinoma, and the remaining one patient had a gastrinoma. The mean age was 59.3±10.5 for pancreatic adenocarcinomas and 45.1±10.6 for PNETs. The mean age at diagnosis was significantly higher in patients with pancreatic adenocarcinomas than the patients with PNET (p<0.001). Preoperative mean hemoglobin levels were significantly lower in patients with pancreatic adenocarcinoma than those with PNET (12.4±1.8g/dl vs 13.7±2.2g/dl), (p<0.013). The preoperative median MPV levels were significantly lower in patients with PNET 7.8fL (7.2-9.4) than in patients with pancreatic adenocarcinomas 8.6fL (6.6-13.5), (p<0.014). In subgroup analysis, a significant difference in MPV levels was mainly caused by the difference between pancreatic adenocarcinomas and non-functional PNETs (p=0.017). The cut-off value of MPV level for detection of PNETs was calculated as≤7.8fL using ROC analysis [Sensitivity: 66.7%, specificity: 75.9%, AUC: 0.734 (0.587-0.880) p=0.022]. In logistic regression analysis, independent predictive factors for determining PNETs in the differential diagnosis of pancreatic adenocarcinomas were calculated as age (OR=0.068, 95% CI: 0.012-0.398), Ca 19-9 (OR=0.039, 95% CI: 0.006-0.263), MPV (OR=0.595, 95% CI: 0.243-1.458), and hemoglobin (OR=1.317, 95% CI: 0.831-2.086).

CONCLUSION

Age, Ca 19-9, MPV, and hemoglobin levels have diagnostic value for distinguishing PNETs from pancreatic adenocarcinomas.

Thrombocytosis: diagnostic evaluation, thrombotic risk stratification, and risk-based management strategies

Thrombocytosis is a commonly encountered clinical scenario, with a large proportion of cases discovered incidentally. The differential diagnosis for thrombocytosis is broad and the diagnostic process can be challenging. Thrombocytosis can be spurious, attributed to a reactive process or due to clonal disorder. This distinction is important as it carries implications for evaluation, prognosis, and treatment. Clonal thrombocytosis associated with the myeloproliferative neoplasms, especially essential thrombocythemia and polycythemia vera, carries a unique prognostic profile, with a markedly increased risk of thrombosis. This risk is the driving factor behind treatment strategies in these disorders. Clinical trials utilizing targeted therapies in thrombocytosis are ongoing with new therapeutic targets waiting to be explored. This paper will outline the mechanisms underlying thrombocytosis, the diagnostic evaluation of thrombocytosis, complications of thrombocytosis with a special focus on thrombotic risk as well as treatment options for clonal processes leading to thrombocytosis, including essential thrombocythemia and polycythemia vera.

Platelet function in rheumatoid arthritis: arthritic and cardiovascular implications

Patients with rheumatoid arthritis (RA) are at high risk of cardiovascular events. Platelet biomarkers are involved in inflammation, atherosclerosis and thrombosis. Cardiovascular and RA-associated factors can alter the structure and function of platelets, starting from megakaryocytopoiesis. Reactive megakaryocytopoiesis increases circulating platelets count and triggers hyperactivity. Hyperactive platelets target synovial membranes with subsequent local rheumatoid inflammation. Hyperactive platelets interact with other cells, and target the vascular wall. Accumulating evidence suggests that disease modifying anti-rheumatic drugs (DMARD) decrease platelet activity.

Platelet function in rheumatoid arthritis: arthritic and cardiovascular implications

Patients with rheumatoid arthritis (RA) are at high risk of cardiovascular events. Platelet biomarkers are involved in inflammation, atherosclerosis and thrombosis. Cardiovascular and RA-associated factors can alter the structure and function of platelets, starting from megakaryocytopoiesis. Reactive megakaryocytopoiesis increases circulating platelets count and triggers hyperactivity. Hyperactive platelets target synovial membranes with subsequent local rheumatoid inflammation. Hyperactive platelets interact with other cells, and target the vascular wall. Accumulating evidence suggests that disease modifying anti-rheumatic drugs (DMARD) decrease platelet activity.

Increased cancer risks among arthroplasty patients: 30 year follow-up of the Swedish Knee Arthroplasty Register

BACKGROUND

An increasing number of young patients are undergoing knee arthroplasties. Thus, the long-term risks of having a knee prosthesis must be evaluated. This study focuses on the potential carcinogenic effects of the prosthesis; it is a long-term follow-up of all patients in Sweden between 1975 and 2006.

METHODS

The incidence of cancer in a total population of operated individuals was compared to the overall national cancer incidence in Sweden by means of standardised incidence ratios. Analysis of cancer latency period was performed to identify potential aetiological factors.

RESULTS

For male and female patients with rheumatoid arthritis (RA) or osteoarthritis (OA), the overall cancer risks were elevated, ranging from 1.10 (95% confidence interval (CI): 1.03-1.18) for men with OA to 1.26 (1.23-1.29) for men with RA. The greatest increases in risk were observed for the leukaemia subtypes, myelodysplastic syndromes (MDS) and essential thrombocytosis (ET), ranging from 3.31 (1.24-8.83) for ET in men with OA to 7.38 (1.85-29.51) for ET in women with RA. Increases in risk were also observed for breast cancer, prostate cancer and melanoma. The latency analysis revealed elevated risks late in the study period for both solid and haematopoietic cancers. However, only increases in MDS and possibly prostate cancer and melanoma rates appeared to be connected to the operation.

CONCLUSION

This study showed that OA and RA arthroplasty patients have a significantly higher risk of cancer than the general population. Elevated risks of MDS and possibly prostate cancer and melanoma indicated a potential connection to exposure to metals in the implant. The observed excessive incidence of ET was likely associated with the inflammatory disease.

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.

Postoperative thrombocytosis as a marker for complications after urologic surgery

OBJECTIVE

To determine whether thrombocytosis after urologic surgery is a random phenomenon or if it is related to postoperative complications.

MATERIAL AND METHODS

We evaluated the postoperative course of patients who had a normal platelet count before surgery and developed significant thrombocytosis (platelet count> 500 x 10(9)/l) after surgery during the years 1991-2003. The rate of postoperative complications was compared among patients who did and did not develop thrombocytosis for the three commonest surgical procedures associated with the condition (radical cystectomy, percutaneous nephrolithotripsy and nephrectomy).

RESULTS

A total of 179 patients developed thrombocytosis (mean+/-SD platelet count 580+/-105 x 10(9)/l; range 501-1,390 x 10(9)/l) after a mean of 13.6 days (SD 14.7 days) following surgery. In 90% of these patients, postoperative complications were diagnosed. The most frequent complications were as follows: urosepsis, n = 49 (27%); hemorrhage, n = 37 (21%); and thromboembolism, n = 15 (8.4%). These complications were diagnosed by means of clinical examination in 114 cases (64%), CT in 31 (17%), Doppler ultrasound in seven (4%) and other diagnostic modalities in nine. In 18 patients (10%), no apparent complication was diagnosed. The rate of postoperative complications was significantly higher among patients who developed thrombocytosis after surgery compared to those who did not (p < 0.00001). In 63 patients (35%), the finding of thrombocytosis preceded the diagnosis of the complication (by a median period of 5 days). In these patients, thrombocytosis was essentially an early marker for the impending complication.

CONCLUSIONS

Postoperative thrombocytosis is not a random phenomenon. It is a serious sign that should not be ignored. Septic and thromboembolic complications should be actively sought by means of thorough clinical evaluation. CT of the abdomen should be considered in appropriate clinical settings. The timing of thrombocytosis and the pathologic spectrum of diseases demonstrated by patients with it justify classifying it as a marker of the subacute phase.

Consistent up-regulation of Stat3 Independently of Jak2 mutations in a new murine model of essential thrombocythemia

Janus-activated kinase 2 (JAK2) mutations are common in myeloproliferative disorders; however, although they are detected in virtually all polycythemia vera patients, they are found in approximately 50% of essential thrombocythemia (ET) patients, suggesting that converging pathways/abnormalities underlie the onset of ET. Recently, the chromosomal translocation 3;21, leading to the fusion gene AML1/MDS1/EVI1 (AME), was observed in an ET patient. After we forced the expression of AME in the bone marrow (BM) of C57BL/6J mice, all the reconstituted mice died of a disease with symptoms similar to ET with a latency of 8 to 16 months. Peripheral blood smears consistently showed an elevated number of dysplastic platelets with anisocytosis, degranulation, and giant size. Although the AME-positive mice did not harbor Jak2 mutations, the BM of most of them had significantly higher levels of activated Stat3 than the controls. With combined biochemical and biological assays we found that AME binds to the Stat3 promoter leading to its up-regulation. Signal transducers and activators of transcription 3 (STAT3) analysis of a small group of ET patients shows that in about half of the patients, there is STAT3 hyperactivation independently of JAK2 mutations, suggesting that the hyperactivation of STAT3 by JAK2 mutations or promoter activation may be a critical step in development of ET.

The effect of drug interactions on bleeding risk associated with warfarin therapy in hospitalized patients

BACKGROUND

Bleeding is a serious adverse drug reaction associated with warfarin therapy, often induced by interacting co-medication.

METHODS

We investigated the frequency and clinical consequences of warfarin drug interactions utilizing medical records of 6,772 warfarin-treated in-patients of Turku University Hospital.

RESULTS

A total of 48% of warfarin-treated in-patients were exposed to interacting co-medication. Adjusted odds ratio (OR) for bleeding was highest for cytochrome P450 2C9 (CYP2C9) inhibitors (OR 3.6; 95% confidence interval (CI) 2.4-5.6). Non-selective non-steroidal anti-inflammatory drugs (NSAID) and coxibs were associated with a bleeding risk of a similar magnitude (OR 2.6; 95% CI 1.6-4.2 and OR 3.1; 95% CI 1.4-6.7, respectively). Selective serotonin re-uptake inhibitors (SSRI) were associated with a remarkably higher bleeding risk than non-SSRIs (OR 2.6; 95% CI 1.5-4.3 and OR 1.2; 95% CI 0.3-4.3, respectively). Odds ratio for bleeding in the platelet aggregation inhibitor group was 1.6 (95% CI 0.8-3.1).

CONCLUSION

We conclude that co-medication in warfarin-treated in-patients is common and should be carefully evaluated to decrease the bleeding risk associated with warfarin therapy.

Mean platelet volume (MPV) as an inflammatory marker in ankylosing spondylitis and rheumatoid arthritis

AIMS

The aim of this retrospective study was to investigate the correlation between MPV and the clinical disease activity indices of rheumatoid arthritis and ankylosing spondylitis.

METHODS

The study consisted of 32 active RA patients (males/females: 7/25, mean age: 49+/-13) and 30 active AS patients (males/females: 15/15, mean age: 36+/-12) along with 26 osteoarthritis (OA) patients (males/females: 4/22, mean age: 52+/-8) and 29 age-matched healthy subjects (males/females: 5/24, mean age: 41+/-7) as control groups for RA and AS, respectively.

RESULTS

MPV was significantly lower in both AS patients and RA patients with active disease as compared to controls (RA vs OA p<0.001, AS vs healthy subjects p<0.001). After treatment MPV values significantly increased in AS and RA (p<0.001 for all). However, MPV values remained somewhat lower in RA patients than OA patients (p=0.019). There was a negative correlation between MPV values and BASDAI scores in AS patients after two months of treatment (r=-0.507; p=0.004).

CONCLUSION

Our results suggest that assessment of MPV may provide additional information about inflammation in AS and RA.

Platelets: the universal killer?

For many, the final terminal event in life is cessation of the heart beat. In turn, this is generally because this organ has been deprived of oxygen and glucose as the blood can no longer deliver these requirements to the myocardium. The principal reason for this is blockage of one or more coronary arteries or arterioles by platelet rich thrombus. A similar process exists for the pathophysiology of stroke--a disabilitating and often fatal event caused by occlusion or rupture of arteries in, or feeding, the brain. These scenarios are best developed in cardiovascular disease, but apply to almost all human disease. Therefore, the ultimate culprit for these major life events is the overactive platelet-too ready to form an inappropriate thrombus. Thus, one way forward in postponing an occlusive thrombotic event is to minimise platelet activation, new tools and treatments for which are eagerly sought.

Poor prognosis indicated by nucleated red blood cells in peripheral blood is not associated with organ failure of the liver or kidney

BACKGROUND

The appearance of nucleated red blood cells (NRBCs) in peripheral blood is associated with a variety of severe diseases. When NRBCs are detected in blood, this is generally associated with increased mortality.

METHODS

In a prospective study, NRBCs and other laboratory parameters were measured daily in the peripheral blood of surgical intensive care patients. The appearance of NRBCs was analyzed in relation to laboratory indicators of organ injury.

RESULTS

A total of 284 surgical intensive care patients were included in this study. The mortality of NRBC-positive patients was 44.0% (40/91). This was significantly higher (p<0.001) than the mortality of NRBC-negative patients (4.2%, 8/193). Mortality increased with the NRBC concentration and the length of the NRBC-positive period. Multiple logistic regression analysis of several other clinical and laboratory risk indicators revealed a significant association between NRBCs and increased mortality, with an odds ratio of 1.95 (95% CI 1.35-2.82; p<0.001) for each increment in NRBC category (0, 1-40, 41-80, 81-240 and >240 NRBC/microL). After the initial detection of NRBCs in blood, there were no significant increases in creatinine concentrations or alanine aminotransferase activity. However, the appearance of NRBCs coincided with increasing C-reactive protein and thrombocyte concentrations.

CONCLUSIONS

The detection of NRBCs in blood of surgical intensive care patients is of prognostic power with regard to patient mortality. This prognostic significance of NRBCs was independent of some clinical and other laboratory risk parameters. The appearance of NRBCs in blood was not associated with kidney failure or lesion of the liver.

The role of megakaryocytes in skeletal homeostasis and rheumatoid arthritis

PURPOSE OF REVIEW

This review provides an update on the role of megakaryocytes in skeletal homeostasis, and discusses these findings in the context of rheumatoid arthritis.

RECENT FINDINGS

Thrombocytosis is a common complication of rheumatoid arthritis, and is presumably caused by an up-regulation in megakaryocytopoiesis. In general, patients with rheumatoid arthritis exhibit localized joint bone erosion with systemic bone loss, and rheumatoid arthritis patients with thrombocytosis tend to have more severe disease. Interestingly, in addition to their role in rheumatoid arthritis with thrombocytosis, it has been demonstrated recently that megakaryocytes play a dual role in regulating skeletal mass by inhibiting bone resorption while simultaneously stimulating bone formation. This seeming contradiction in the putative role of megakaryocytes in skeletal regulation and rheumatoid arthritis is the focus of this review.

SUMMARY

In rheumatoid arthritis there are substantial increases in the levels of several pro-inflammatory pleiotropic cytokines. As would be expected, in addition to their role in inflammation, these cytokines play a critical role in the megakaryocytopoiesis seen in patients who develop reactive thrombocytosis, and these cytokines also are known to regulate osteoclastogenesis. Thus, it appears that in rheumatoid arthritis with reactive thrombocytosis, the ability of the cytokines to enhance osteoclastogenesis outweighs the ability of megakaryocytes to inhibit osteoclastogenesis.

Thrombocytosis accompanying urinary tract infection suggests obstruction or abscess

OBJECTIVE

Reactive thrombocytosis can be found in patients with different types of infections, including upper urinary tract infection (UTI). In this study, we determined whether thrombocytosis in patients with upper UTI is a random phenomenon or is related to complications associated with the UTI.

METHODS

We reviewed the charts of patients admitted to the urology department with a diagnosis of upper UTI and thrombocytosis (platelet count >500 x 10(9)/L) in the years 1991 to 2003 (study group). Patients admitted to the urology department in the year 2003 with a diagnosis of upper UTI without thrombocytosis served as the control group.

RESULTS

The study group consisted of 83 patients admitted to the urology department with a diagnosis of upper UTI and thrombocytosis (mean platelet count, 593 x 10(9)/L; SD, 88; range, 501-949). The control group consisted of 99 patients. An obstructed kidney was found in 54 patients (65%) of the study group and in 18 patients (18%) of the control group (P < .00001). Perinephric abscess was found in 7 patients (8%) in the study group compared with none in the control group (P < .003). The positive predictive value of thrombocytosis for kidney obstruction or abscess in patients with upper UTI was 71%. Nephrectomy of a nonfunctioning infected kidney was required in 6 patients of the study group (7%) and 2 of the control group (P = .14). In 26 patients (31%) of the study group, the finding of thrombocytosis preceded the diagnosis of the complication (by a median period of 3 days). In these patients, thrombocytosis was essentially an early marker for the complication.

CONCLUSIONS

Thrombocytosis in a patient with upper UTI is not a random phenomenon. It is a marker of kidney obstruction or perinephric abscess. The finding of thrombocytosis in a patient with upper UTI should alert the attending physician to actively search for these complications. Cross-sectional imaging study (abdominal ultrasonography or computed tomography) should be performed.

Th1 shift in CIDP versus Th2 shift in vasculitic neuropathy in CSF

To investigate the intra- and extracellular levels of various cytokines and chemokines in CSF in chronic inflammatory demyelinating polyneuropathy (CIDP) and vasculitic neuropathy (VN), 16 cytokines, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 (p70), IL-13, IL-17, IFN-gamma, TNF-alpha, G-CSF, MCP-1 and MIP-1beta, were measured in CSF supernatant by a multiplexed fluorescent bead-based immunoassay and intracellular production of IFN-gamma and IL-4 in CSF CD4+ T cells were simultaneously measured by flow cytometry in 14 patients with CIDP, 8 patients with VN and 25 patients with other noninflammatory neurologic diseases (OND). In the CSF supernatant, a significant increase of IL-17, IL-8 and IL-6, and a significant decrease of IL-4, IL-5 and IL-7 levels were detected in pretreated CIDP as compared with OND. A significant increase of IL-6, IL-8 and IL-10 levels was found in pretreated VN. Both IL-17 and IL-8 levels correlated strongly with CSF protein levels in CIDP, although the correlation of IL-6 levels was weak. In CSF CD4+ T cells, IFN-gamma+ IL-4- cell percentages were markedly elevated in CIDP compared with OND, but not in VN, resulting in a significant increase of intracellular IFN-gamma/IL-4 ratio in CIDP, even in the absence of CSF pleocytosis. The nonresponders to intravenous immunoglobulins (IVIGs) showed a significantly lower IFN-gamma- IL-4+ CD4+ T cell percentage, and tended to have a higher intracellular IFN-gamma/IL-4 ratio than the responders in CSF. Marked upregulation of Th1 cytokine, IL-17, and downregulation of Th2 cytokines, together with infiltration of IFN-gamma-producing CD4+ T cells are useful markers for CIDP, while several Th2 cytokines are upregulated in VN in CSF.

The inflammatory side of human chondrocytes unveiled by antibody microarrays

Although being largely used for pathobiological models of cartilage diseases such as osteoarthritis (OA), human chondrocytes are still enigmatic cells, in as much as a large part of their secretome is unknown. We took advantage of the recent development of antibody-based microarrays to study multiple protein expression by human chondrocytes obtained from one healthy and five osteoarthritic joints, in unstimulated conditions or after stimulation by the proinflammatory cytokines interleukin-1 (IL-1) or tumour necrosis factor (TNF). The secretion media of chondrocytes were incubated with array membranes consisting of 79 antibodies directed against cytokines, chemokines, and angiogenic or growth factors. Several proteins were identified as new secretion products of chondrocytes, including the growth or angiogenic factors EGF, thrombopoietin, GDNF, NT-3 and -4, and PlGF, the chemokines ENA-78, MCP-2, IP-10, MIP-3alpha, NAP-2, PARC, and the cytokines MIF, IL-12, and IL-16. Most of the newly identified chemokines were increased intensely after stimulation by IL-1 or TNF, as for other proteins of the array, including GRO proteins, GM-CSF, IL-6, IL-8, MIP-1beta, GCP-2, and osteoprotegerin. The up-regulation by cytokines suggested that these proteins may participate in the destruction of cartilage and/or in the initiation of chemotactic events within the joint during OA. In conclusion, the microarray approach enabled to unveil part of an as yet unexplored chondrocyte secretome. Our findings demonstrated that chondrocytes were equipped with a proinflammatory arsenal of proteins which may play an important part in the pathogenesis of OA and/or its drift towards an inflammatory, rheumatoid phenotype.