Evaluation of Mannose-Binding Lectin is a Useful Approach to Predict the Risk of Infectious Complications Following Autologous Hematopoietic Stem Cell Transplantation.

Hematopoietic stem cell transplantation (HSCT) associated immunocompromised state carries high risk of infectious complications. Mannose-binding lectin (MBL) is an acute phase protein involved in innate immune response. Serum MBL level is genetically determined and quite stable. According to literature, significant association was shown between low MBL concentrations and serious infections. The association between serum MBL level and frequency and severity of infections was studied in 186 patients following autologous HSCT. Double-monoclonal antibody sandwich enzyme-linked immunosorbent assay was used to determine MBL antigen level in sera. MBL levels were measured around 100 days following transplantation, in a period without active infection. Twenty-one patients (11%) were MBL deficient. The median time of first infection and number of infections during the first year post-transplantation were not significantly different between patients with MBL deficiency and those without MBL deficiency. The occurrence and number of infections after HSCT correlated with the MBL/C-reactive protein ratio. The number of severe infections was not higher among those with MBL deficiency. The occurrence of infections after the pre-engraftment period during the first year post-transplantation was significantly different in patient groups separated by MBL cut-off level. The MBL/C-reactive protein ratio might be a useful marker of infectious complications. MBL measurement may be helpful in antibiotic treatment. In case of MBL deficiency, earlier and more intensive treatment may be indicated.

Complement activation in thrombotic thrombocytopenic purpura.

BACKGROUND: Ultra-large von Willebrand factor and deficiency of its cleaving protease are important factors in the events leading to thrombotic microangiopathy; however, the mechanisms involved are only partly understood. Whereas pathological activation of the alternative complement pathway is linked to atypical hemolytic uremic syndrome, the role of complement activation in thrombotic thrombocytopenic purpura (TTP) is unknown. The aim of this study was to investigate whether signs of complement activation are characteristic of TTP. PATIENTS AND METHODS: Twenty-three patients with TTP (18 women, median age 38 years) and 17 healthy controls (13 women, median age 38 years) were included. Complement parameters (C3, Factors H, I, B and total alternative pathway activity) together with complement activation fragments (C3a) or complexes (C1rs-INH, C3bBbP, sC5b9) were measured by ELISA or RID. ADAMTS13 activity and anti-ADAMTS13 inhibitory antibodies were measured by the VWF-FRET73 assay. RESULTS: Increased levels of C3a, and SC5b9 were observed in TTP during acute episodes, as compared with healthy controls. Decreased complement C3 levels indicative of complement consumption occurred in 15% of acute TTP patients. Significant decrease of complement activation products C3a and SC5b9 was observed during plasma exchange (PEX). The sustained presence of anti-ADAMTS13 inhibitory antibodies in complete remission was associated with increased complement activation. CONCLUSION: These data document in an observational study the presence of complement activation in TTP. Further investigation is needed to determine its potential pathogenetic significance.

Anti-TNF-alpha antibody (infliximab) therapy supports the recovery of eNOS and VEGFR2 protein expression in endothelial cells.

The aim of this study is to investigate the effect of sera obtained from patients of Crohn's disease treated by anti-TNF-alpha antibody (Infliximab) on the expression of endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor receptor-2 (VEGFR2) protein in human umbilical vein endothelial cells (HUVEC) cultured in vitro. HUVEC was cultured in the presence of sera derived from patients before and after treatment, or from healthy individuals. Effects of sera on the expression of eNOS and VEGFR2 were monitored by determination of mRNA and protein levels using real time quantitative PCR and Western blot analysis, respectively. The serum of Crohn's patients contained elevated levels of TNF-alpha (34±1.80 pg/mL), which resulted in a decrease in the protein level of eNOS in HUVEC with a simultaneous induction of VEGFR2. Infliximab treatment normalized the expression level of these proteins by decreasing TNF-alpha level, particularly in those cases when clinical healing was also recorded, and it also conferred restitution of the level of angiogenic cytokines. Results suggest that altered angiogenesis possibly contributes to the initiation and perpetuation of inflammatory processes in inflammatory bowel disease (IBD). Endothelial dysfunction, a selective feature of Crohn's disease is beneficially affected by intravascular TNF-alpha neutralization.

Clinical and immunoserological characteristics of mixed connective tissue disease associated with pulmonary arterial hypertension.

We investigated the clinical characteristics and immunoserological alterations in patients with mixed connective tissue disease (MCTD) associated with pulmonary arterial hypertension (PAH). Anti-U1RNP autoantibodies, anti-endothelial cell antibodies (AECA) and serum thrombomodulin (TM) as well as von Willebrand factor antigen (vWFAg) concentrations were measured in 25 patients with MCTD associated with PAH and in 154 MCTD patients without PAH. The results showed that the probability of survival was lower in MCTD patients with PAH than in the 154 MCTD-non-PAH patients (5-year survival rate in MCTD with PAH: 73%, versus 96% in MCTD-non-PAH; P < 0.01). AECA were more frequently present in the sera of MCTD patients with PAH than in MCTD-non-PAH (P < 0.001). Serum TM and vWFAg levels were higher in MCTD-PAH patients than in MCTD-non-PAH patients (TM: P < 0.001; vWFAg: P < 0.001). Significant correlation was noticed between the quantity of AECA and TM level (r = 0.466) as well as the quantity of AECA and vWFAg level (r = 0.550). In conclusion, our results suggest that in MCTD the presence of AECA and endothelial cell activation may play a role in the development of PAH and in the maintenance of obliterative vascular processes.

The most severe forms of Perthes' disease associated with the homozygous Factor V Leiden mutation.

It has recently been postulated that thrombophilia may have a role in the aetiology of Perthes' disease. The published reports, however, remain conflicting. In this study a retrospective analysis of the coagulation parameters was made in 47 patients with Perthes' disease and the results compared with the clinical data. Five patients with Factor V Leiden mutation were found (10.6%) and surprisingly four of them had a homozygous pattern. These four patients showed the most severe form of the disease, Catterall group IV, with flattening of the entire epiphysis, involvement of the metaphysis, shortening and broadening of the femoral neck, trochanteric overgrowth and developed mushroom-shaped aspherical laterally displaced femoral heads in dysplastic acetabula. We would like to suggest that the homozygous form of Factor V Leiden mutation has some role in the clinical course of Perthes' disease and particularly its most severe form.

Effects of in vitro platelet activation on platelet derived nitric oxide production in healthy humans and in chronic myeloproliferative diseases with elevated platelet counts.

Intravascular EDRF-NO production is known to be impaired in some diseases, e.g., diabetes. This phenomenon may also contribute to the development of diabetic vascular disease. More recently the presence of NO synthase (ecNOS, iNOS) have been recognized in human platelets. Platelets produce NO only during activation, even though in minute amounts. This platelet derived NO seems to play an important physiological role, as it inhibits further platelet recruitment quite substantially. In the present report washed platelets isolated from healthy persons and patients with chronic myeloproliferative diseases (CMPD) were exposed to common and physiologically relevant activators (i.e., thrombin, collagen, epinephrine etc.). These tests were carried out in 20 healthy volunteers and 15 patients suffering from myeloproliferative disorders associated with thrombocytosis. As a consequence of pathological platelet function observed in CMPD, the in vitro platelet NO response is impaired in the patient group. One may assume, that reduced platelet NO response, at least in part, may contribute to platelet hyperfunction, angiopathy and thrombotic complications in some cases of CMPD.

[Comments about dosing of low molecular weight heparins (LMWH)]. / Gondolatok a kis molekulatömegú heparinok (LMWH) adagolásáról.

Low molecular weight heparins (LMWHs) have different schedules for dosage according to the official descriptions and recommendations prepared by the particular manufacturer. Therapeutic regimens are mainly depending on bodyweight, even if data concerning the possible effects body composure (i.e. in obesity, lean body mass) are apparently more or less missing. Prophylactic doses are either based on bodyweight (or just an approximation, weight-frames) or mainly perioperative cases on the assessment of the surgical risk. Manufacturers are busy to supply easy and convenient way to approach dosage and prepare, providing fixed, frequently used amounts of LMWHs in disposable syringes. On the other hand haematologist may or should assess bodyweight, history of thrombosis, thrombophilia or bleeding risk, and disease or intervention simultaneously, and may look for a synthetic estimation of an individual dose for each patient. It is rather difficult to establish, which way should be preferred. This review tries to analyse pros and cons in respect of dose estimation with LMWHs in therapy or prophylaxis.

The possible association of in vivo leukocyte-platelet heterophilic aggregate formation and the development of diabetic angiopathy.

Circulating leukocyte-platelet heterophilic aggregates produce procoagulant, oxidative and mitogenic substances, and can cause microembolism in capillaries as well as acute arterial thrombosis. Our aim was to determine if there was any difference in the number of circulating heterophilic aggregates between diabetic patients and controls, if the formation of aggregates correlated with the actual HgbA1c level, duration of diabetes and postprandial rise in serum glucose level, with different vascular complications and whether decreasing postprandial serum glucose had any effect on heterophilic aggregate formation. The number of circulating heterophilic aggregates was measured in 90 diabetic patients (Type 1, 29; Type 2, 61) and in 23 control subjects by a flow-cytometric assay, and the result was given as percentage of the respective leukocyte subsets. There was no significant difference in lymphocyte-platelet and neutrophil-platelet aggregate number in patients and controls; however, there was a significant difference in the percentage of monocyte-platelet aggregates between the diabetic and control group (Type 1, 43.0 +/- 17.8; Type 2, 34.9 +/- 12.5; control, 24.6 +/- 8.2; P < 0.01 and P < 0.5, respectively). Patients with proliferative retinopathy and nephropathy showed the highest number of monocyte-platelet aggregates. No significant correlation was, however, found with HgbA1c. In Type 2 diabetes a non-significant, but remarkable, tendency between elevation of postprandial serum glucose levels and platelet-monocyte aggregate formation was observed and acarbose seemed to be effective in decreasing both. This study provides further support that heterophilic aggregates might have role in the pathogenesis of diabetic vascular complications.

[Molecular biology examination in chronic lymphocytic leukemia]. / Molekuláris biológiai vizsgálatok krónikus lymphoid leukaemiában.

Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia characterised by the accumulation of monoclonal CD5 + B-lymphocytes. The pathogenesis and the biology of CLL is complex and many details are still unknown. Several molecular biological methods have been used in the investigation of CLL, among them the study of apoptosis appears to be one of the most important. Initial experiences obtained by the spontaneous and fludarabine induced apoptosis, multidrug resistance (MDR)-test and fluorescent in situ hybridization (FISH) are reported by the authors. Apoptosis of CLL cells could be induced by fludarabine, while more studies should be performed to determine the exact role of MDR-test and FISH.

[Hematologic aspects of inflammatory bowel diseases]. / A gyulladásos bélbetegségek hematológiai vonatkozásai.

Anaemia, thrombocytosis are common secondary changes in inflammatory bowel disease (IBD), reflecting the clinical severity of the IBD cases, too. On the other hand, increased platelet function, fibrinolytic abnormalities, hypercoagulation of IBD patients predispose to thromboembolic events, and they may as well contribute to the local microcirculatory alterations leading to IBD itself. Reduced FXIII levels have been observed in IBD, which seems to be correlated with mucosal repair and might have therapeutic importance, too. Genetic thrombophilia received much attention recently, however, much less is known how frequent they are in IBD, what their clinical significance is, do they modify the clinical course itself. A short, concise review about links between haematology and IBD is given.

[Disseminated intravascular coagulation(DIC)]. / Disszeminált intravascularis coagulatio (DIC).

Disseminated intravascular coagulation (DIC) remains a multifaced syndrome, which may develop with different background and aetiology into venous thromboembolism (mainly chronic, paraneoplastic DIC) or into severe bleeding, factor consumption, thrombocytopenia (i.e. gynaecological acute DIC) or may appear as microthrombotic organ hypoperfusion, organ-failure and necrosis (septic DIC variant). The understanding and consideration of pathogenetic events promotes better identification and interpretation of DIC syndrome and its categories, render more adequate diagnostics and therapy available. The vast majority of new data accumulated in the septic type of DIC, and this general review also tries to put the major emphasis on sepsis-DIC link, laboratory diagnosis and apparent new therapeutic approaches.

[Immune thrombocytopenic purpura (ITP)]. / Immunthrombocytopeniás purpura (ITP).

Immune thrombocytopenic purpura (ITP) belongs to the major classical entities of clinical haematology. Diagnosis is still based on documentation of "megakaryocytic thrombocytopenia" and exclusion of other factors, diseases. The childhood (mainly acute) and adult type (mainly chronic) seem to differ substantially, and run different prognosis as well as response to therapeutic measures. A lasting remission or cure is uncommon with corticosteroids alone in the chronic cases, so splenectomy is frequently necessary and indicated. Standard therapy is poorly defined or established in splenectomy refractory cases, which situation requires experience, therapeutic skills and special care. There are many promising efforts to spare splenectomy, especially in younger patients. New standards are also recommended in ITP crisis situations (wet purpura, pregnancy and delivery, splenectomy, etc.). Standard as well as innovative approaches, focusing on clinical care, are briefly evaluated and reviewed in this report.

[Cerebral deep vein thrombosis associated with rectal cancer]. / Rectumcarcinomával társult agyi mélyvénás thrombosis.

The authors report a case where the patient suffered from deep cerebral venous thrombosis, which developed beside cerebral metastases of a colorectal cancer. The pathogenesis and diagnosis of this disease are also discussed. This rare location of thrombosis is mainly due to hypercoagulable state seen in the use of oral contraceptive drugs, Behçet syndrome, nephrotic syndrome, and as paraneoplastic syndrome in malignant diseases. Literature reports less than 50 cases of deep cerebral venous thrombosis, of which less than 10 are evoked by malignant disease. The symptoms of DCVT can mimic cerebral metastases in cancer patients. The course of disease is aggressive, the prognosis is poor. Even if the patients survive considerable neurological deficits may remain. Authors emphasize the importance of current modern diagnostic imaging methods in the diagnosis. The possibility of deep cerebral venous thrombosis must be taken into account if sudden neurological symptoms develop in a cancer patient.

[Fluorescence in situ hybridization in the diagnosis and follow-up of chronic myelogenous leukemia]. / Fluoreszcencia in situ hibridizációval szerzett tapasztalataink a krónikus myeloid leukaemia diagnosztikájában és követésében.

Chronic myelogenous leukaemia is a clonal myeloproliferative stem cell disease. Its cytogenetical hallmark is the Philadelphia chromosome (Ph) or the BCR/ABL fusion gene. Their identification is important both in the diagnosis and the follow-up of the disease. In our department we have investigated the BCR/ABL gene arrangement in 21 patients with fluorescence in situ hybridization. The aim of the analysis in freshly suspected patients without any previous therapy was to confirm diagnosis and mapping the ratio of Philadelphia positive cells. In contrast to the 95-100% Ph-positivity of mononuclear cells by classical cytogenetical examinations we found BCR/ABL gene arrangement only in various but always lower proportions. Therefore the latter examination gives a better representation of residual normal hemopoesis. Out of 9 patients who had received interferon treatment for at least 6 months, 4 gave a major, 4 a minor cytogenetical answer and in 1 case there was no cytogenetical response. Seven patients reached a complete and 2 a partial hematological remission. Among 5 other patients receiving interferon treatment, in 2 cases with double Ph-positivity we found a rapid progression. The data of 3 patients had to be excluded from the evaluation due to the so far short following time.

Increased leukocyte-platelet adhesion in chronic myeloproliferative disorders with high platelet counts.

The heterophilic adhesions between monocytes and platelets may result in the modification of both platelet and monocyte function. This mutual modification includes a greater activation of platelets with increased production of PDGF and other metabolites as well as an enhanced tissue factor expression of monocytes with greater activity in the circulation. The heterophilic aggregation has been well documented during extracorporal circulation, haemodialysis and in diabetic retinopathy. Here we provide evidence that there is significant increase of monocyte-platelet aggregates in disorders associated with high platelet counts, such as chronic myeloproliferative disorders. The presence of these heterophilic aggregates may contribute to the vascular complications observed frequently in polycythaemia vera and essential thrombocythaemia.

[Detection of minimal residual diseases in B-cell tumors using PCR specific for the immunoglobulin heavy chain gene]. / A minimális reziduális betegség kimutatása B-sejtes tumorok esetében az immunglobulin nehézlánc génre specifikus polimeráz láncreakció segítségével.

In B-cell non-Hodgkin's lymphomas (NHL), clonal rearrangement of the immunoglobulin heavy chain (IgH) gene provides a useful marker for the detection of minimal residual disease (MRD) after treatment. To explore clinical usefulness of polymerase chain reaction (PCR) analysis of clonal IgH gene rearrangement in the detection of MRD a follow up study of 10 patients with B-cell NHL have been performed. At the time of diagnosis, tumor DNAs were PCR-amplified using sense primer specific for the heavy chain variable region (VH) and antisense primer specific for the heavy chain joining region (JH) of the IgH gene. The clonal rearrangement of IgH gene detected by PCR was used as clonal marker to determine MRD after treatment. In three cases, where clinical remission was not achieved, clonal IgH gene rearrangement was detected after the treatment. In seven cases, clinical remission was achieved after induction therapy but the PCR analysis revealed clonal IgH gene rearrangement in three of the cases. In all of the three cases, where MRD was detected by PCR, clinical relapse developed after 7-28 months of the therapy. In all cases that have relapsed, the IgH gene rearrangement was identical at the time of initial diagnosis and at the relapse. This study demonstrates that PCR analysis of clonal IgH gene rearrangement is a useful method to monitor and detect MRD before clinical relapse.

[Hemostasis in liver diseases]. / Májbetegségek és haemostasis.

Liver plays central role in the synthesis and metabolism of the pro- and anticoagulant enzymes of blood coagulation. Acute or chronic liver failure frequently result in different bleeding phenomena. Thrombocytopenia due to hypersplenism and lack of haemopoietic factors seems to be common, but in spite of thrombocytopenia and more or less platelet malfunction thrombocytopenic bleeding is usually less prominent feature. Bleeding esophageal varices, clotting abnormalities with peritonejugular shunts may pose many difficulties in clinical practice. Transjugular intrahepatic shunt (TIPS) has been a major step forward treating refractory esophageal bleeding or ascites, however to keep the stent patent seems to be still unresolved. Along with the bleeding tendency or symptoms concommittant venous thromboembolic events are may not be considered as rare events in cirrhosis. Special problems are also coupled with ascites, which contains an almost full inventory of coagulation proteins, also with the medical and interventional therapy of Budd-Chiari syndrome, and other veno-occlusive conditions with or without transplantation.

[The role of alpha-interferon therapy in chronic myeloid leukemia]. / Az alpha-interferon-kezelés szerepe krónikus myeloid leukaemiában.

Alpha-interferons are widely accepted and used in chronic myeloid leukaemia. The standard indication is the chronic phase, and it seems to be clear, that by prolonging the chronic phase interferon therapy results in better overall survival than busulphan or hydroxyurea (this comparison needs metaanalysis) monotherapy. A review and recommendation is given considering the indications (with a special attention to stemcell transplantation), dosage, contraindications and monitoring interferon treatment.