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L Chrobák

Publications and source records attributed to L Chrobák.

At least 19 recordsLinked to original sources

The significance of soluble CD138 in diagnosis of monoclonal gammopathies.

Report is summary of the results of study designed to ascertain the significance of soluble CD138 (sCD138) assessment in patients with different monoclonal gammopathies. Previous studies have shown that sCD138 is shed from the surface of myeloma cells into serum and that this marker is a new independent prognostic parameter in multiple myeloma. In presented study was evaluated serum sCD138 level in 14 patients with monoclonal gammopathy of undetermined significance (MGUS) and in 17 patients with multiple myeloma (MM), all MM patients were treated by high-dose chemotherapy regimen with subsequent autologous transplantation of peripheral blood stem cells. To determine the sCD138 level we used a rapid and simple ELISA procedure. The mean serum sCD138 level of patients with MGUS was 32 ng/ml (range: 5-128). Soluble CD138 levels were elevated in the sera of 10 out of 17 (59%) multiple myeloma patients, the mean baseline sCD138 concentration was 1542 ng/ml (range: 10-17300). In spite of small number of patients the difference between MGUS and MM group was highly statistically significant (p<0.001). Multiple myeloma patients with high level of sCD138 at diagnosis (cut-off value: 500 ng/ml) had worse prognosis despite of good response to chemotherapy in some of them (p=0.029). It seems that determination of sCD138 can be recommended as a helpful and reliable marker for differential diagnosis as well as prognosis of monoclonal gammopathies.

Biomarkers↗

[Combination of imatinib and anagrelide in treatment of chronic myeloid leukemia in blastic phase].

Chronic myeloid leukemia in blast phase (BP) is resistant to chemotherapy and majority of patients die within 6 months. Inhibitor Bcr-Abl tyrosine kinase imatinib mesylate dramatically improved outcome of patients in chronic phase (CP) and is also effective in BP of CML. The prognosis of patients treated with imatinib in BP is worse than in CP. High platelet counts are often observed at diagnosis or in the subsequent course of the CML in about 25% of patients. Thrombohemorrhagic complications associated with the thrombocythemia may be serious. Anagrelide selectively reduces circulating platelets and is used in treatment of thrombocythemia in chronic myeloproliferative disorders. Efficacy and safety of combination imatinib mesylate with anagrelide was demonstrated in chronic and accelerated phase of CML. No study about the use of imatinib with anagrelide in BP has been found. 51-year-old white man with CML presented in blast phase was followed for 4 years. Imatinib mesylate in dose of 600 mg p.o. qd. was administered after the failure of initial chemotherapy. The patient was treated with imatinib for 45 months, 14.5 months in combination with anagrelide. Partial hematologic response in duration of 33 months was induced by imatinib, cytogenetic response was not reached. Imatinib-resistant thrombocythemia was controlled with anagrelide in dose of 0.5-1 mg p.o. qd. No thrombohemorrhagic complications were observed. The patient tolerated the combination of imatinib and anagrelide well and long-term survival gave him the chance of treatment with the new tyrosin kinase inhibitor (dasatinib).

Antineoplastic Agents↗

[The idiopathic hypereosinophilic syndrome and chronic eosinophilic leukemia].

Idiopathic hypereosinophilic syndrome is a heterogenous group of hematological disorders characterized by eosinophilia (> 1.5 x 10(9)/l) persistent for more than 6 months, exclusion of reactive eosinophilia from other causes, such as parasitic infections or allergy, and evidence of end-organ damage. According to World Health Organization the exclusion includes all neoplastic disorders in which eosinophils are part of the neoplastic clone. Excluded should be also T cell population with aberant phenotype and abnormal cytokine production, recently considert also as "lymphocytic" variants of the HES [42]. HES has to be reclassified as chronic eosinophilic leukemia (CEL) when there is evidence for clonality based on the presence of chromosomal abnormalities or inactivation of X-chromosome in female patients. The successful empiric treatment of patients with tyrosine kinase inhibitor imatinib (Glivec) suggested the presence of an imatinib-sensitive tyrosine kinase inhibitor. The identification of a specific intersticial chromosome deletion del(4)(q12;q12) creating the FIP1L1-PDGFRA fusion gene confirmed this hypothesis. Patients carrying this gene should be reclassified as CEL and detection of this gene is a positive predictor for response to imatinib therapy. Effective doses of imatinib are 100 mg/day. The side effects are minimal. The only exception is an acute left ventricular dysfunction which has been reported in three patients within the first week of treatment with imatinib. Imatinib has been successfully used also in some patients with the constitutively activated thyrosine kinase ETV6-PDGFRbeta [1] and in systemic mast cell disease associated with eosinophilia. Other therapeutical options for HES/CEL have been mentioned. The resistence to imatinib and the possibilities how to overcome it are discussed.

Chronic Disease↗

[Imatinib mesylate (Glivec) in treatment of chronic phase chronic myeloid leukemia].

The new knowledge in molecular biology and pathophysiology of chronic myeloid leukemia enabled the development of imatinib mesylate (Glivec, formerly STI571). Imatinib potently inhibits several protein tyrosine kinases, including BCR-ABL, c-Kit, and PDGF receptor. Imatinib blocks the phosphorylation of downstream target proteins and interrupts the malignant transformation leading to the development of CML. Phase I and II studies demonstrated that imatinib is highly effective and well tolerated in all phase of CML. We got our experience with imatinib on more than two-year monitoring 34 patients within the Expanded Access Study CST1571 0113. Imatinib 400 mg/d was administered orally to 10 women and 24 men in median age of 53 years (22-70) who were hematologically (n = 9) or cytogenetically (n = 13) resistant, cytogenetically refractory (n = 3) or intolerant (n = 9) to interferon alpha. The median follow-up time was 97.5 weeks (23-115), the median time from CML diagnosis to the start of the study was 32.3 months (6-140.5). Complete hematologic response was achieved in 33 of 34 (97%) pts, total major cytogenetic response (complete plus major) in 21 of 33 (63%) pts. Cytogenetic relapse was observed in 2 of 33 pts (6%), cytogenetic progression in 4 (12%) pts. Non-hematologic toxicity was mild (grade 1 or 2) and no patient was excluded from the study due to it. Hematological toxicity grade 3 limited dose of imatinib in 26% of patients and probably caused lower rate of cytogenetic responses in heavy pretreated patients. Both quantitative RT-PCR methods (competitive RT-PCR and real-time RT-PCR Light-Cycler) were found useful to monitor patients with CML on imatinib therapy. Our results confirmed high efficacy and safety of imatinib in late-chronic phase CML patients failing prior interferon therapy. The lower incidence of hematological toxicity and higher rate of cytogenetic responses in patients treated with imatinib in early-chronic phase CML justify according to our opinion the recommendation to administer imatinib early after the diagnosis of CML in patients who are not indicated for allogeneic transplantation.

Adult↗

[Splenomegaly (clinical importance, diagnosis and therapy)].

An enlarged spleen is a frequent and important clinical sign. It may be a presenting or dominant feature of a number of primary blood diseases as well as other clinical disorders of different etiology. The splenic structure consisting of the white pulp, the red pulp and intermediate marginal zone together with a complicated splenic blood flow enable the spleen to fulfill its functions: filtration (phagocytosis), immunological function, reservoir of blood and its corpuscules and extramedullary hematopoiesis in certain diseases. Enlargement of the spleen may occur as a result of various pathological conditions. This article is based on the history, physical examination and laboratory routine test results as proposed approach to the differential diagnosis of splenomegaly. Progress and changes in management of blood diseases resulted in reappraisal of indications for splenectomy. Progress in surgery has made it possible to perform splenectomy under videolaparoscopic control avoiding laparotomy.

Diagnosis, Differential↗

[Diagnosis and therapy of idiopathic thrombocytopenic purpura (ITP) in adults].

Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder resulting from the binding of antibodies directed toward platelet surface glycoproteins GP IIb/IIIa and GP Ib/IX leading to their clearance by reticuloendothelial system. The diagnosis of ITP is made clinically by exclusion of other causes of thrombocytopenia. The treatment of chronic ITP is palliative, not curative and is directed toward inactivation and removal of a major site of platelet destruction and antibody production represented by the spleen. Spontaneous remission of ITP in adults are very rare. The goal of treatment for ITP is to prevent serious bleeding. About 30% of the affected patients show a long term response to steroid therapy. Splenectomy is the treatment of choice in the remaining patients. The treatment of patients refractory to corticosteroid therapy and splenectomy remains largely empirical and to date a generally accepted therapy has not been established. The newest approch to the treatment involves the use of monoclonal antibodies. In intracranial bleeding and in severe bleeding in refractory ITP use of rVIIa has been shown to might be useful. ITP in pregnancy represent a special situation. There is the trend toward treating these patients in a more conservative fashion.

Adult↗

Myelodysplastic and myeloproliferative type of chronic myelomonocytic leukemia--distinct subgroups or two stages of the same disease?

Several authors have tried to solve the problems in the classification of CMML. A fully suitable classification does not exist. The goal of our study was to determine common and different signs of MD and MP type of CMML and to observe frequency of shifts from MD to MP-CMML. Sixty nine CMML patients were divided according to FAB proposal into two groups: 31 patients into the MD group (WBC < or = 13 x 10(9)/l) and 38 patients into the MP group (WBC < or = 13 x 10(9)/l). Presenting features and the course of the disease in both groups were evaluated. The median age of patients was not different in both groups (71.5 and 74 years, respectively), male/female ratio was 1.1 and 2.4, respectively. The median follow-up time was 15.5 months (1-58.8) in MP group and 24 months (2-118) in MD group. In MP group splenomegaly, hepatomegaly, lymphadenopathy, abnormal karyotype and skin involvement were found more often than in MD group. Median LDH value was higher in MP group. Probability of survival was higher in the MD group than in MP group (median 30 and 11 months, respectively). Leukaemia transformation frequency was similar in both groups. In 12 out of 24 (50%) MD group patients WBC increased during the course of the disease over 13 x 10(9)/l. Oscillation of WBC values below and over 13 x 10(9)/l was observed in three patients. During the follow-up time number of patients with splenomegaly and/or immature granulocytes in the PB increased. After inclusion of 12 patients who shifted from MD to MP group a new CMML group resulted characterised by longer median survival (17 months) due to a higher number of patients in an earlier stage of the disease. Failure of evolution of myeloproliferative signs and lower frequency of AL in the remaining group might be explained by an early stage of CMML, untimely deaths due to unrelated causes and/or by patients suffering of RA with monocytosis rather than of CMML. In summary, our data suggest, that evolution from MD-CMML to MP-CMML is a frequent event and that MD-CMML could be the early stage of CMML in most of cases. The WBC at diagnosis as the single criterion for subclassification of CMML does not seem to be fully justified. We propose that CMML should not be divided in MD and MP types and that monitoring of patients and search for other signs of myeloproliferation such as PB immature granulocytes, splenomegaly, lymphadenopathy, skin involvement, pleural or peritoneal effusions, spontaneous growth of CFU-GM in vitro should be taken in consideration for a better classification of CMML, which would have an impact on the therapeutic approach.

Adult↗

The degree of bone marrow infiltration in patients with hairy cell leukemia treated with splenectomy compatible with long-term hematological remission.

To determine the degree of bone marrow infiltration with hairy cells which is compatible with long-term hematological remission in patients treated with splenectomy, we have investigated 7 patients surviving in hematological remission 61 to 255 months (median 184 months) after splenectomy. As hematological remission has been considered absence of hairy cells (HCs) in the peripheral blood, normalization of peripheral blood cell counts (hemoglobin 120 g/l, white cell count 4.0 x 10(9)/l, absolute granulocyte count 1.5 x 10(9)/l, platelet count 100 x 10(9)/l) and absence of lymfadenopathy and any other activity of the disease. For detection of HCs a very sensitive method of immunostaining with monoclonal antibody DBA.44 in our own modification has been used. Low values of sIL-2R which is considered to be a non invasive marker of tumor burden and activity in HCL were in agreement with the opinion that the bone marrow was the only locality of tumor involvement in splenectomized patients. Infiltration up to 20% with HCs (range 4% to 20%, median 10%) was found to be compatible with long-term hematological remission and long-term overall survival. Patient (No 1) with 30% infiltration of bone marrow with HCs, still normal peripheral blood cell counts, but a very high level of sIL-2R represents extraordinary finding which has been discussed in details.

Adult↗

[Treatment of paroxysmal nocturnal hemoglobinuria (PNH)].

Paroxysmal nocturnal hemoglobinuria is an acquired clonal disorder of the hematopoietic stem cell in which intravascular hemolysis is due to an intrinsic defect in the membrane of red cells that makes them increasingly susceptible to lysis by complement. The phenotypic hallmark of PNH cells is an absence or marked deficiency of GPI-anchored proteins such as CD 59+, CD 55+ and others which normally protect cells from the action of complement. PHN is closely associated with aplastic anemia. Some degree of bone marrow failure is always present. Management of PNH is complicated by a highly variable clinical picture and course. Some patients have severe anemia aggravated by hemolytic crises and associated thromboses. Bone marrow failure is accompanied with frequent infections and hemorrhagic manifestations due to thrombocytopenia. With the exception of marrow transplantation, no definite therapy is available. In the exceptional circumstance in which the patient has a syngeneic twin, bone marrow transplantation is the most appropriate therapy for severe PNH because of absence of graft-versus-host disease. In general syngeneic transplantation without preconditioning has been unsuccessful because abnormal hematopoiesis returns. Allogeneic bone marrow transplantation has been used, but the transplant-associated morbidity and mortality are high due mainly to the fatal graft-versus-host disease and severe posttransplant marrow failure. Use of an unrelated donor transplant has to be considered as contraindicated. PNH is associated with striking predisposition to intravascular thrombosis which often involves the portal system or the brain. Fatal thromboses account for about 40-50% of all deaths in patients with PNH. The etiology of the thrombophilia in PNH is not fully clarified. Anticoagulation or thrombolytic therapy is required for treatment of venous thrombosis, the latter vena cava. Prophylactic anticoagulation in patients without contraindications such as severe thrombocytopenia seems to be justified. However, whether such therapy may be efficacious in reducing the incidence of thromboses or affect survival is conjectural. PNH patients have varying degree of platelet activation and some authors suggest that antiplatelet therapy might be efficacious in reducing the incidence and severity of venous thrombosis in PNH. Pregnancy is hazardous. Female patients should avoid the use of oral contraceptives. Pregnant patients require combined care of an experienced hematologist and obstetrician specialized in the management of high-risk pregnancies.

Anemia, Aplastic↗

[History of chest percussion].

Although percussion of the abdomen was already known to the Greek physician Galenos (2nd century A. D.) who used it to distinguish between ascites and meteorism, the Viennese physician Leopold Auenbrugger (1722-1809) started to use, the percussion of the chest as a diagnostic tool. In 1761 he published his experience in a treatise called "New Method for Detecting Hidden Ailments of the Chest by Percussion of the Thorax" (Inventum novum ex percussione thoracis hummani ut signo abstruso interni pectoris morbos detergendi). However, this method was introduced into practice only 50 years later by Jean Nicolas Corvisart, who translated Auenbrugger's book in 1808 into French. The famous Vinnese internist of Czech origin Joseph Skoda (1805-1881) set the teaching about percussion and auscultation on a firm physical basis. Skoda confronted the physical findings with dissection materials in close cooperation with the renowned Vinnese pathologist Karl Rokitansky (1804-1878), who was born in Hradec Králové. The Medical School in Prague became famous for its excellent command of methods based on physical examination and surpassed even the Viennese School.

History, 15th Century↗

[Microcytic and hypochromic anemias].

In the majority of cases, microcytosis is the result of impaired hemoglobin synthesis. Disorders of iron metabolism and protoporphyrin and heme synthesis, as well as impaired globin synthesis, lead to defective hemoglobin production and to the generation of microcytosis and microcytic anemia. Iron deficiency anemie, anemia of chronic diseases, thalassemias, congenital sideroblastic anemias and homozygous HbE disease are the main representatives of microcytosis and microcytic anemias. Serum iron, total iron binding capacity, transferrin saturation, serum ferritin, serum transferrin receptor, transferrin receptor-ferritin index, and zinc-protoporhyrin concentration in erythrocytes are tests used for assessment of iron deficiency. The convention laboratory test for diagnosing iron deficiency is the measurement of serum ferritin. The most precise method for evaluating body iron stores is the examination for iron on aspirated bone marrow or marrow biopsy. Increased content of Hb A2 over 3.5% is diagnostic for beta-thalassemia. Presence of ringed sideroblasts is characteristic of sideroblastic anemias. Hemoglobin electrophoresis is required for the diagnosis of hemoglobinopathy E. The optimal therapeutic regimen in iron deficiency anemia used in this country is to administer 100 mg of elemental iron twice daily separately from meals. Ferrous sulphate (Ferronat Retard tbl. or Sorbifer Dulures tbl.) which are slow-releasing iron formulations are preferred because of their low cost, high bioavailability and low side-effects. Parenteral iron therapy is justified only in patients who cannot absorb iron, who have blood losses that exceed the maximal absorptive capacity of their intestinal tract or who are totally intolerant of oral iron. However, parenteral iron therapy may be associated with serious and even fatal side-effects.

Anemia, Hypochromic↗

Paroxysmal nocturnal hemoglobinuria (membrane defect, pathogenesis, aplastic anemia, diagnosis).

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disorder in which intravascular hemolysis results from the somatic mutation of the totipotent stem cells causing an intrinsic defect in red cell membrane. PNH cells lack glycosylphosphatidylinositol (GPI) anchored membrane proteins. Of these proteins absence of CD 59 (MIRL--membrane inhibitor of reactive lysis, protectin) and CD 55 (DAF--decay accelerating factor) makes the PNH cells abnormally sensitive to the lytic action of complement. The defect appears to be in the somatic mutation of the X-linked PIG-A (phosphatidylinositolglycan A class) gene which participate in an early step of GPI-anchor synthesis. PNH is characterized by recurrent life threatening venous thromboses and an intimate association with aplastic anemia (AA). It seems that PNH always coexists with bone marrow failure (BMF) (37). The possible explanation may be that some GPI-anchored proteins may be a critical target recognized by immune effector cells. PNH clones not possessing these critical GPI-anchored proteins will survive because they are selectively resistant to the autoimmune assault that eliminates most normal clones. The flow cytometry of erythrocytes using anti-CD 59 and anti-CD 59 and anti-CD 55 of granulocytes has been now introduced as a very sensitive and quantitative method of PNH diagnosis able to detect PNH cells even in normal individuals (1,54). Thus it seems now clear that we must make distinction between the detection of very occasional PNH cells in patients with BMF and PNH as a clinicohematological entity. Unfortunately, we do not know the minimal content of PNH cells required to produce clinical signs of PNH (38).

Anemia, Aplastic↗

[Monitoring minimal residual disease in patients with hairy cell leukemia in complete remission after treatment with 2-chlorodioxyadenosine].

Treatment of hairy cell leukemia with 2-chlorodeoxyadenosine (2-CdA) induces in 85% patients complete remission. Complete remission is defined as the condition when signs of activity of the disease are absent, splenomegaly and lymphadenopathy are absent, the hemoglobin concentration is > or = 120 g/l, the absolute number of granulocytes is > or = 1.5 x 10(9)/l and the number of thrombocytes is > or = 100 x 10(9)/l. In complete remission in the peripheral blood, bone marrow aspirate and bioptic samples obtained by trephin bone marrow core biopsy, using standard staining (hematoxylin-eosin and May-Grünwald-Giemsa's method), no leukemic cells are present. When more sensitive methods are used (immunophenotyping, immunohistochemistry or molecular genetic methods), a persisting leukemic population can be detected which is described as minimal residual disease (MRD). For detection of MRD the authors used immunohistochemical examination of bone marrow with DBA.44 antibodies. As leukemic cells they described those which produced intense cytoplasmic and membrane positivity with antibody DBA.44 and corresponded morphologically to hairy cells. For evaluation computer analysis of the picture LUCIA-M was used. The infiltration grade was examined on three areas of standard size (3 x 65,265 micron 2) and expressed in percent. A total of 45 trepanobioptic specimens from 21 patients were examined who achieved after treatment with 2-CdA complete remission. In all samples suitable for evaluation the presence of leukemic cells (MRD) was detected with a median of 3% and a range of 1% to 18%. With induction of complete remission correlates also the low serum level of the soluble receptor for IL-2 (sIL-2R). In a female patient after 24 months of treatment with 2-CdA the grade of leukemic infiltration rose from 1% to 12% and during the 36th month to 50% DBA.44+ leukemic cells. The incipient relapse in this patient was not associated, despite marked infiltration of bone marrow, with failure of hematopoiesis and a marked rise of sIL-2R.

Adult↗

Minimal residual disease, its detection and significance in hairy-cell leukemia.

As minimal residual disease (MRD) is considered the detection of hairy cells (HCs) in a patient with hairy cell leukemia (HCL) in complete remission with the absence of detectable HCs by routine morphology of peripheral blood, aspirates and bone marrow core sections, using more sensitive methods of identification as immunohistological staining or polymerase chain reaction (PCR) to detect immunoglobulin heavy chain genes rearrangement. Various monoclonal antibodies (MoAbs) as CD20, DBA.44, B ly-7, HC2, CD25 and CD11c have been applied using immunological staining. There is no standardized technique for identification of MRD. According to the technique used the MRD has been detected in 13% to 100% of patients in complete remission (CR). It may be concluded that many patients, if not all, in stable CR may have residual HCs. Whether MRD will have impact on early relapse or on long term outcome, or whether patients in CR with persistent MRD will remain so, is a matter of a longer follow-up.

Antibodies, Monoclonal↗

Is factor V Leiden a risk factor for fetal loss?

A successful pregnancy is dependent on the development of adequate placental circulation. The abnormalities of placental vasculature may result in a number of gestational pathologies, including fetal loss. The aim of our study was to determine whether women with f V Leiden are at an increased risk of pregnancy loss. For this purpose we assessed three groups of women. In a prospective group we examined 30 females with spontaneous abortions for f V Leiden. In a retrospective group we assessed the frequency of abortions in 80 women (172 pregnancies) with f V Leiden (72 heterozygous, 8 homozygous) from 57 unrelated families. In a control group we evaluated the frequency of abortions in 45 women without f V Leiden. Factor V Leiden was found in 3% of women in the 1st group. Fetal loss occurred in 10% of women in the 2nd group and in 9% in the 3rd group. Factor V Leiden was not found to be a risk factor for fetal loss in our study group.

Abortion, Spontaneous↗

[Thrombophilic states].

Thrombophilia is defined as an increased tendency to thrombosis and can be inherited or acquired. The thrombotic events in patients with inherited thrombophilia tend to occur at a young age, are often idiopathic, recurrent and may occur at unusual sites (e.g. mesenteric, portal and cerebral veins and in inferior vena cava). The most common of the hereditary defects appear to be antithrombin, protein C, protein S deficiency, which account for 10% of individuals presenting with venous thromboembolism, resistance to anticoagulant effect of activated protein C (APC-R), which is present in 17 to 64% of patients with thrombosis and prothrombin 20210 G-->A variant with 6% prevalence in patients with thrombosis. APC-R is due in 90% to the presence of factor V Leiden. Rarer defects include heparin cofactor II (HC II), plasminogen or tissue plasminogen activator deficiency (TPA), elevated plasminogen activator inhibitor-1 (PAI-1) and dysfibrinogenemia. The most common acquired defects are antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies). Hyperhemocystinemia is responsible as well for arterial as venous thrombosis. A substantial proportion of venous thrombotic events occurs spontaneously, i.e. without a precipitating event. Risk factors for thrombosis include surgery, trauma, immobility, congestive heart failure, pregnancy including puerperium and oral contraceptive usage. The thrombotic risk is increased in patients who are homozygous for factor V Leiden and markedly increased in patients with combined defects.

Female↗