Michael Voulgarelis

Hematologic manifestations and predictors of lymphoma development in primary Sjögren syndrome: clinical and pathophysiologic aspects.

The diverse hematologic manifestations of primary Sjögren syndrome (pSS) have not been systematically investigated, and their prognostic relevance remains unclear. We conducted a retrospective study of 536 consecutive patients followed in our institution to assess the prevalence of hematologic abnormalities and their associations with various disease manifestations in pSS. We also aimed to identify risk factors for the development of non-Hodgkin lymphoma (NHL) overall and by subtype. Anemia of chronic disease and hypergammaglobulinemia were the most prevalent hematologic manifestations encountered at diagnosis and during the course of pSS. Univariate analysis between cytopenias and glandular manifestations revealed a statistically significant correlation between lymphocytopenia and parotid gland enlargement (p = 0.002), as well as between neutropenia and xerostomia (p = 0.019). Anemia, lymphocytopenia, thrombocytopenia, hypergammaglobulinemia, the presence of monoclonal serum proteins, and cryoglobulinemia correlated significantly with the presence of extraglandular symptoms such as palpable purpura, lymphadenopathy, and splenomegaly. Lymphoma was diagnosed in 7.5% (95% confidence interval [CI], 5.4%-10%) of patients. Marginal zone B-cell lymphomas (MZBCLs) were the predominant histologic type (65%; 95% CI, 48.3%-79.4%), while diffuse large B-cell lymphomas (DLBCLs) accounted for 17.5% (95% CI, 7.3%-32.8%) of all cases. The development of NHL in patients with pSS could be predicted by the presence of simple clinical and laboratory factors at diagnosis: neutropenia (p = 0.041), cryoglobulinemia (p = 0.008), splenomegaly (p = 0.006), lymphadenopathy (p = 0.021), and low C4 levels (p = 0.009). Patients carrying any of these factors had a more than 5-fold increased risk of NHL compared to patients with no risk factors at all. The above set of disease characteristics could predict subsequent development of MZBCL; the presence of lymphocytopenia (p = 0.044) at diagnosis served as a risk factor for the development of a non-MZBCL, most commonly DLBCL. Anemia of chronic disease and hypergammaglobulinemia are common hematologic manifestations at diagnosis and during the course of pSS. Neutropenia and cryoglobulinemia at diagnosis are significantly associated with an increased risk of lymphoma development. Abbreviations: AECC = American-European Consensus Classification, CI = confidence interval, DLBCL= diffuse large B-cell lymphoma, HR = hazard ratio, MALT = mucosa-associated lymphoid tissue, MZBCL = marginal zone B-cell lymphoma, NHL = non-Hodgkin lymphoma, NPV = negative predictive value, PPV = positive predictive value, pSS = primary Sjögren syndrome.

Pathogenetic mechanisms in the initiation and perpetuation of Sjögren's syndrome

Sjögrens syndrome (SS), a chronic autoimmune disorder, particularly compromises the function of exocrine glands. The involvement of these glands is characterized by focal, mononuclear cell infiltrates that surround the ducts and replace the secretory units. The pathogenetic mechanisms of this autoimmune exocrinopathy have not been fully elucidated. Immunologically-activated or apoptotic glandular epithelial cells that expose autoantigens in genetically predisposed individuals might drive autoimmune-mediated tissue injury. Alterations in several immune mediators, such as upregulation of type I interferon-regulated genes, abnormal expression of B-cell-activating factor and activation of the interleukin-23–type 17 T-helper cell pathway, have been reported. Extension of the pathological process that affects the exocrine glands into periepithelial and extraepithelial tissue can cause a considerable percentage of patients to exhibit systemic findings that involve the lungs, liver or kidneys. These manifestations develop as a result of lymphocytic invasion or an immune-complex-mediated process, or both, and present as skin vasculitis coupled with peripheral neuropathy or glomerulonephritis (or both). Patients with systemic extraepithelial manifestations display low serum levels of the complement component C4 and mixed type II cryoglobulins, and show an increased risk of developing non-Hodgkin lymphoma, thereby reflecting an overall worse prognosis with higher mortality rates than those without extraepithelial manifestations.

Heparin treatment in antiphospholipid syndrome with recurrent pregnancy loss: a systematic review and meta-analysis.

OBJECTIVE: To estimate the effect of combined heparin and aspirin compared with aspirin monotherapy in pregnant women with antiphospholipid syndrome and recurrent pregnancy loss. DATA SOURCES: We searched the PubMed database up to December 2009 for English-language studies using the key words “aspirin AND (heparin OR low molecular weight heparin), (antiphospholipid OR anticardiolipin OR aPL) AND pregnancy.” METHODS OF STUDY SELECTION: Two hundred ninety- two studies were initially screened. Randomized controlled trials comparing the effect of heparin (unfractionated heparin or low molecular weight heparin) plus aspirin compared with aspirin alone on the live-birth rate in women with a history of at least two miscarriages and antiphospholipid antibodies were eligible. TABULATION, INTEGRATION, AND RESULTS: The pooled effect of unfractionated heparin and low molecular weight heparin was evaluable in three and two randomized controlled studies, respectively, with regard to live births, which was the major outcome. Overall, treatment effects were in favor of heparin against first-trimester losses (odd ratio [OR] 0.39, 95% confidence interval [CI] 0.24–0.65, number needed to treat 6). More specifically, unfractionated heparin displayed a significant effect (OR 0.26, 95% CI 0.14–0.48, number needed to treat 4), while the pooled effect of low molecular weight heparin was insignificant (OR 0.70, 95% CI 0.34–1.45). Combination therapy of either unfractionated heparin or low molecular weight heparin with aspirin failed to display any significant effect in the prevention of late-pregnancy losses. No significant differences were observed between treatment and control groups for any other outcomes. CONCLUSION: The combination of unfractionated heparin and aspirin confers a significant benefit in live births. However, the efficacy of low molecular weight heparin plus aspirin remains unproven, highlighting the urgent need for large controlled trials.

Prognosis and outcome of non-Hodgkin lymphoma in primary Sjögren syndrome.

AbstractSjögren syndrome (SS) has been associated with the development of non-Hodgkin lymphoma (NHL). From a cohort of 584 SS patients followed in our department from 1980 to 2010, we retrospectively analyzed 53 consecutive NHL cases. Considerations included histologic type, clinical manifestation and NHL staging, treatment, response rate and overall survival (OS), event-free survival (EFS), and standardized mortality ratio (SMR).Mucosa-associated lymphoid tissue (MALT) lymphomas constituted the majority (59%) of NHL subtypes, followed by nodal marginal zone lymphomas (NMZLs) (15%) and diffuse large B-cell lymphomas (DLBCLs) (15%). Six lymphoma patients died during the median follow-up of 40.8 months. The corresponding age/sex-adjusted SMR of SS with and without NHLs versus the general population was 3.25 (95% confidence interval [CI] 1.32–6.76) and 1.08 (95% CI, 0.79–1.45), respectively. A “watch and wait” policy was adopted for 9 patients with asymptomatic localized salivary MALT lymphomas. Eight patients with limited-stage MALT lymphomas and extraglandular manifestations were treated with rituximab. Ten MALT lymphoma patients with disseminated disease received chemotherapy with or without rituximab. The 3-year OS and EFS in patients with MALT lymphomas was 97% and 78%, respectively. Rituximab plus CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) was the chosen therapeutic intervention for patients with DLBCLs. A successful outcome was recorded for this group, with 100% OS and EFS at 3 years. Patients with NMZLs had a less favorable outcome, with a 3-year OS of 80% and EFS of 53%. Our results describe the course and prognosis of SS-associated NHL and highlight the need for a risk-stratified treatment approach.

Is JAK2 V617F mutation more than a diagnostic index? A meta-analysis of clinical outcomes in essential thrombocythemia.

A systematic review and meta-analysis was carried out to compare the frequency of clinically significant outcomes between JAK2 V617F positive and wild type patients with essential thrombocythemia (ET). JAK2 V617F positivity in patients with ET was associated with a clear increase in the odds of thrombosis [OR=1.83 (95% CI, 1.32-2.53), p<0.0001], and much higher odds of transformation to polycythemia vera [OR=7.67 (95% CI, 2.04-28.87), p=0.0009]. The mean difference of the white blood cell count between JAK2 positive and negative patients was associated with an increased odds ratio for thrombosis (p=0.02). The JAK2 V617F mutation in patients with ET is associated with an increased risk of adverse cardiovascular outcomes via an increase in the leukocyte count.

Anaemia in systemic lupus erythematosus: from pathophysiology to clinical assessment

Haematological abnormalities are common in systemic lupus erythematosus. Anaemia is found in about 50% of patients, with anaemia of chronic disease being the most common form. Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the pathogenesis of this type of anaemia. Patients with autoimmune haemolytic anaemia usually belong to a distinct category, which is associated with anticardiolipin antibodies, thrombosis, thrombocytopenia, and renal disease, often in the context of secondary antiphospholipid syndrome. Autoantibodies, T lymphocytes, and deregulation of the cytokine network can affect bone marrow erythropoiesis, leading to anaemia.

Thrombosis in paroxysmal nocturnal hemoglobinuria: sites, risks, outcome. An overview

MEDLINE Database (1953 to 2006) has been extensively reviewed using the terms PNH, Thrombosis and Paroxysmal Nocturnal Hemoglobinuria, Thrombosis as search criteria; 294 citations were retrieved. Eligible articles were reviews, cohort studies, and case reports providing individual patient data on the site of thrombosis and outcome (death or survival) related to the thrombotic event. Ninety-three articles (nine cohort studies and 84 case reports and reviews of published cases) provided data on 363 PNH cases with thrombosis and outcome in 339 cases. When the same case was reported twice, in a review article and as a case report, only one of the citing articles was included as a data source. When either the site of thrombosis or the outcome was not evident, this case was excluded. Our study population finally consisted of 339 cases of PNH with thrombosis. Treatment options were available in 162 cases and were classified as conventional (n 1⁄4 118) (for those receiving unfractionated heparin, low molecular weight heparin, or warfarin) and interventional modalities (n 1⁄4 44), either to restore blood flow (thrombolysis, anatomic shunts, angioplasty) or reverse coagulation defect (bone marrow transplantation). Odds ratios with their corresponding 95% confidence intervals (CIs) were measured to quantify relative risk of death (RR) in univariate and multivariate logistic regression models. A score chart was developed to facilitate the practical application of the multivariate regression model. The regression coefficients of the significant covariates were rounded off to the proximal 0.5. The value of each predictor (site of thrombosis) has a corresponding score in the chart. The scores are added, resulting in a sum score, which corresponds to a probability according to a logistic transformation. For the significant sites of thrombosis associated with mortality, the population attributable mortality (PAM) was also calculated and depicted. PAM is defined as the proportion of deaths occurring in the total study population (PNH patients with thrombosis) that can be explained by the risk factor (site of thrombosis). Assigned score corresponds to an individual’s probability to die when a thrombosis at this specific site occurs. Instead, PAM refers to the proportion of deaths in the whole study population that is attributed to the particular exposure (specific site of thrombosis). Significance was set to 0.05. The STATA V8 (Stata Corporation, College Station, TX, USA) package was used for statistical analysis.

Long term remission of Sjögren’s syndrome associated aggressive B cell non-Hodgkin’s lymphomas following combined B cell depletion therapy and CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone)

Background: Primary Sjögren’s syndrome (SS) is associated with an increased frequency of non-Hodgkin’s lymphomas (NHLs), mainly of low histological grade. However, aggressive diffuse large B cell lymphomas (DLBCL) characterised by poor treatment outcome can also be encountered in SS. It has recently been shown that rituxan has significant therapeutic activity in this type of lymphoma. Objective: To evaluate the efficacy of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisone) in combination with rituxan in SS patients with DLBCL, and to determine the outcome in such patients. Methods: In an open, single case trial, six SS patients with DLBCL were assigned to receive eight cycles of CHOP every three weeks plus rituxan given on day 1 of each cycle. In a retrospective study, conducted by the European Concerted Action for SS, nine cases were diagnosed as DLBCL, all of whom had been treated with CHOP alone. These patients were used as historical controls. Results: The difference in the overall survival between the two treatment groups was significant. The group treated with rituxan plus CHOP had a 100% two year overall survival rate, while the historical controls had only a 37% survival rate. Extraglandular manifestations serving as predictors for lymphoma development such as palpable purpura and peripheral neuropathy disappeared. The remission of these signs was accompanied by a decrease in both circulating monoclonal cryoglobulins and rheumatoid factor activity and an increase in C4 levels. Clinically relevant toxicity was not detected. Conclusions: The addition of rituxan to standard CHOP chemotherapy results in improved treatment outcome in SS patients with aggressive DLBCL, without increasing toxicity.

Toll-like Receptor-4 Is Up-Regulated in Hematopoietic Progenitor Cells and Contributes to Increased Apoptosis in Myelodysplastic Syndromes

Purpose: To investigate the function and expression of Toll-like receptors (TLR) in bone marrow cells of myelodysplastic syndrome (MDS) patients and to examine their involvement in the apoptotic phenomenon characterizing MDS hematopoiesis. Experimental Design: TLR mRNA and protein expression was investigated in bone marrow cell populations of MDS patients and controls. TLR-4 ability to recognize lipopolysaccharide and up-regulate self mRNA and protein expression was examined. Tumor necrosis factor involvement in the constitutive and lipopolysaccharide (LPS)-induced TLR expression was also evaluated. Possible correlation between TLR-4 overexpression and apoptosis was investigated by simultaneous staining with Annexin V and TLR-4. Results: TLR-2 and TLR-4 are expressed in almost all bone marrow cell lineages including megakaryocytes, erythroid cells, myeloid precursors, monocytes, and B lymphocytes and are up-regulated in MDS patients compared with controls. In hematopoietic CD34+ cells, TLR-4 is also expressed and significantly up-regulated at both the mRNA and protein levels. Treatment with an anti–tumor necrosis factor antibody reduces both constitutive and LPS-induced TLR-4 levels. Increased TLR-4 expression correlates with increased apoptosis as TLR-4 is almost exclusively found in apoptotic bone marrow mononuclear and CD34+ cells. The addition of the TLR-4 ligand LPS further enhances the apoptosis of these cells. Conclusions: TLR-4 and other TLRs are significantly up-regulated in MDS patients whereas TLR-4 is involved in promoting apoptosis, possibly contributing to MDS cytopenia.

Toll-Like Receptors, Tissue Injury, and Tumourigenesis

Toll-like receptors (TLRs) belong to a class of molecules known as pattern recognition receptors, and they are part of the innate immune system, although they modulate mechanisms that impact the development of adaptive immune responses. Several studies have shown that TLRs, and their intracellular signalling components, constitute an important cellular pathway mediating the inflammatory process. Moreover, their critical role in the regulation of tissue injury and wound healing process as well as in the regulation of apoptosis is well established. However, interest in the role of these receptors in cancer development and progression has been increasing over the last years. TLRs are likely candidates to mediate effects of the innate immune system within the tumour microenvironment. A rapidly expanding area of research regarding the expression and function of TLRs in cancer cells and its association with chemoresistance and tumourigenesis, and TLR-based therapy as potential immunotherapy in cancer treatment is taking place over the last years.