Application of targeted next generation sequencing for the mutational profiling of patients with acute lymphoblastic leukemia.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children, whereas it is less common in adults. Identification of cytogenetic aberrations and a small number of molecular abnormalities are still the most important risk and therapy stratification methods in clinical practice today. Next generation sequencing (NGS) technology provides a large amount of data contributing to elucidation of mutational landscape of childhood (cALL) and adult ALL (aALL). METHODS: We analyzed DNA samples from 34 cALL and aALL patients, using NGS targeted sequencing TruSeq Amplicon - Cancer Panel (TSACP) which targets mutational hotspots in 48 cancer related genes. RESULTS: We identified a total of 330 variants in the coding regions, out of which only 95 were potentially protein-changing. Observed in individual patients, detected mutations predominantly disrupted Ras/RTK pathway (STK11, KIT, MET, NRAS, KRAS, PTEN). Additionally, we identified 5 patients with the same mutation in HNF1A gene, disrupting both Wnt and Notch signaling pathway. In two patients we detected variants in NOTCH1 gene. HNF1A and NOTCH1 variants were mutually exclusive, while genes involved in Ras/RTK pathway exhibit a tendency of mutation accumulation. CONCLUSIONS: Our results showed that ALL contains low number of mutations, without significant differences between cALL and aALL (median per patient 2 and 3, respectively). Detected mutations affect few key signaling pathways, primarily Ras/RTK cascade. This study contributes to knowledge of ALL mutational landscape, leading to better understanding of molecular basis of this disease.

Incidence and Mortality Patterns of Acute Myeloid Leukemia in Belgrade, Serbia (1999⁻2013).

Introduction: To assess incidence and mortality trends of acute myeloid leukemia (AML) in Belgrade (Serbia) in a 15-year period (from 1999 to 2013). Material and Methods: Data were obtained from the Cancer Registry of Serbia, Institute of Public Health of Serbia. Standardized incidence and mortality rates per 100,000 inhabitants were calculated by direct standardization method using World Standard Population. Analysis of raw data indicated single-digit numbers per year and per 5-year age cohorts. Therefore, we merged years of diagnosis to three-year intervals, creating so-called "moving averages". We also merged study population to 10-year age cohorts. Results: Both incidence and mortality rates increased with age, i.e., the lowest rates were observed in the youngest age groups and the highest rates were observed in oldest age groups. In all age groups, except the youngest (15⁻24 years), AML incidence was statistically significantly higher in men compared with women. Average age-adjusted incidence was 2.73/100,000 (95% confidence interval (CI) 2.28⁻3.71). Average age-adjusted mortality was 1.81/100,000 (95% CI 1.30⁻2.26). Overall, there were no significant changes in incidence trend. Age-adjusted incidence rates had increasing tendency among men aged 65⁻74 years (B = 0.80, standard error (SE) = 0.11; p = 0.005) and in total population aged 65⁻74 years (B = 0.41, SE = 0.09; p = 0.023). Increasing tendency in incidence of AML among women was observed in age group >75 years (B = 0.63, SE = 0.14; p = 0.019). No changes of mortality trend were observed. Conclusion: There was no significant change in trends of AML from 1999 to 2013 in the population of Belgrade.

Use of Wilms Tumor 1 Gene Expression as a Reliable Marker for Prognosis and Minimal Residual Disease Monitoring in Acute Myeloid Leukemia With Normal Karyotype Patients.

BACKGROUND: Acute myeloid leukemia with normal karyotype (AML-NK) represents the largest group of AML patients classified with an intermediate prognosis. A constant need exists to introduce new molecular markers for more precise risk stratification and for minimal residual disease (MRD) monitoring. PATIENTS AND METHODS: Quantitative assessment of Wilms tumor 1 (WT1) gene transcripts was performed using real-time polymerase chain reaction. The bone marrow samples were collected at the diagnosis from 104 AML-NK patients and from 34 of these patients during follow-up or disease relapse. RESULTS: We found that overexpression of the WT1 gene (WT1high status), present in 25.5% of patients, was an independent unfavorable factor for achieving complete remission. WT1high status was also associated with resistance to therapy and shorter disease-free survival and overall survival. Assessment of the log reduction value of WT1 expression, measured in paired diagnosis/complete remission samples, revealed that patients with a log reduction of < 2 had a tendency toward shorter disease-free survival and overall survival and a greater incidence of disease relapse. Combining WT1 gene expression status with NPM1 and FLT3-ITD mutational status, we found that the tumor behavior of intermediate patients (FLT3-ITD-/NPM1- double negative) with WT1high status is almost the same as the tumor behavior of the adverse risk group. CONCLUSION: WT1 expression status represents a good molecular marker of prognosis, response to treatment, and MRD monitoring. Above all, the usage of the WT1 expression level as an additional marker for more precise risk stratification of AML-NK patients could lead to more adapted, personalized treatment protocols.

Somatic mutations of isocitrate dehydrogenases 1 and 2 are prognostic and follow-up markers in patients with acute myeloid leukaemia with normal karyotype.

BACKGROUND: Mutations in the isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) genes are frequent molecular lesions in acute myeloid leukaemia with normal karyotype (AML-NK). The effects of IDH mutations on clinical features and treatment outcome in AML-NK have been widely investigated, but only a few studies monitored these mutations during follow-up. PATIENTS AND METHODS: In our study samples from 110 adult de novo AML-NK were studied for the presence of IDH1 and IDH2 mutations, their associations with other prognostic markers and disease outcome. We also analyzed the stability of these mutations during the course of the disease in complete remission (CR) and relapse. RESULTS: IDH mutations were found in 25 (23%) patients. IDH+ patients tend to have lower CR rate compared to IDH-patients (44% vs 62.2%, p = 0.152), and had slightly lower disease free survival (12 months vs 17 months; p = 0.091). On the other hand, the presence of IDH mutations had significant impact on overall survival (2 vs 7 months; p = 0.039). The stability of IDH mutations were studied sequentially in 19 IDH+ patients. All of them lost the mutation in CR, and the same IDH mutations were detected in relapsed samples. CONCLUSIONS: Our study shows that the presence of IDH mutations confer an adverse effect in AML-NK patients, which in combination with other molecular markers can lead to an improved risk stratification and better treatment. Also, IDH mutations are very stable during the course of the disease and can be potentially used as markers for minimal residual disease detection.

Hypercalcemia with multiple osteolytic lesions and increased circulating tumor necrosis factor in an adult patient with B-cell acute lymphoblastic leukemia.

INTRODUCTION: Acute lymphoblastic leukemia (ALL) is very rarely presented with diffuse osteolytic lesions and hypercalcemia. CASE OUTLINE: We report a 28-year-old male with the B-cell ALL who presented with extensive osteolytic lesions, bone pain, hepatosplenomegaly, and pancytopenia without circulating blasts in peripheral blood. An increased serum level of tumor necrosis factor (TNF-α) was registered while the levels of IL-1α and IL-1ß were normal. The patient failed to achieve remission on two induction regimens but achieved one after the successful allogeneic stem cell transplantation, which lasted for six months, after which he developed a relapse and died. CONCLUSION: The presented case may serve as a clinical demonstration of possible involvement of TNF-α as a pathogenic factor in the evolution of osteolytic lesions that are occasionally observed in patients with ALL. This might have relevance in the management of such patients as chemotherapy alone may not represent the beneficial option in this clinical context.

Parallel targeted next generation sequencing of childhood and adult acute myeloid leukemia patients reveals uniform genomic profile of the disease.

The age-specific differences in the genetic mechanisms of myeloid leukemogenesis have been observed and studied previously. However, NGS technology has provided a possibility to obtain a large amount of mutation data. We analyzed DNA samples from 20 childhood (cAML) and 20 adult AML (aAML) patients, using NGS targeted sequencing. The average coverage of high-quality sequences was 2981 × per amplicon. A total of 412 (207 cAML, 205 aAML) variants in the coding regions were detected; out of which, only 122 (62 cAML and 60 aAML) were potentially protein-changing. Our results confirmed that AML contains small number of genetic alterations (median 3 mutations/patient in both groups). The prevalence of the most frequent single gene AML associated mutations differed in cAML and aAML patient cohorts: IDH1 (0 % cAML, 5 % aAML), IDH2 (0 % cAML, 10 % aAML), NPM1 (10 % cAML, 35 % aAML). Additionally, potentially protein-changing variants were found in tyrosine kinase genes or genes encoding tyrosine kinase associated proteins (JAK3, ABL1, GNAQ, and EGFR) in cAML, while among aAML, the prevalence is directed towards variants in the methylation and histone modifying genes (IDH1, IDH2, and SMARCB1). Besides uniform genomic profile of AML, specific genetic characteristic was exclusively detected in cAML and aAML.

Peripartum cardiomyopathy in a patient treated for acute myeloid leukemia.

INTRODUCTION: Peripartum cardiomyopathy usually presents with systolic heart failure during the last months of pregnancy and up to five months postpartum. The disease is rare and can be fatal. CASE OUTLINE: We report a 30-year-old female who was diagnosed with acute myeloid leukemia, with maturation and cytogenetic finding of t(8;21)(q22;q22),del(9)(q22) in January 2004. She was treated with chemotherapy and achieved complete remission that lasts to date. She became pregnant and delivered a healthy newborn with caesarean section in 2009. Seven months later, she again became pregnant and delivered the second child with caesarean section in January 2011. Seven days after delivery she developed symptoms and signs of heart failure. Electrocardiogram showed sinus rhythm, low voltage and negative T-waves in inferior and lateral leads. Echocardiography revealed global left ventricular dysfunction with ejection fraction of 15%, with mobile thrombotic mass of 12 mm attached to the left ventricle wall. She was treated with both unfractionated and low-molecular heparin, diuretics, cardiotonics, and beta-blockers. Within six following weeks left ventricle systolic function improved up to 25-30%. The full clinical recovery was achieved in September 2013, resulting in absence of heart failure and left ventricular ejection fraction of 54%. CONCLUSION: Peripartum cardiomyopathy is a rare condition. The cause of cardiomyopathy is unknown, but it is believed that it could be triggered by various conditions and risk factors. Although the patient was treated with cardiotoxic drugs (doxorubicin and mitoxantrone) in permitted doses, they could have been contributory factors of myocardial damage. Close monitoring of cardiac function in the peripartal period might be beneficial in patients treated with cardiotoxic drugs.

Mucormycosis of the paranasal sinuses in a patient with acute myeloid leukemia.

Introduction: Invasive fungal infection is among the leading causes of morbidity, mortality, and economic burden for patients with acute leukemia after induction of chemotherapy. In the past few decades, the incidence of invasive fungal infection has increased dramatically. Its management has been further complicated by the increasing frequency of infection by non-Aspergillus molds (e.g. Mucorales). Neutropenic patients are at a high risk of developing an invasive mucormycosis with fulminant course and high mortality rate (35­100%). Case Outline: We are presenting the case of a 72-year-old male with an acute monoblastic leukemia. The patient was treated during five days with hydroxycarbamide 2 × 500 mg/day, followed by cytarabine 2 × 20 mg/sc over the next 10 days. He developed febrile neutropenia, headache, and edema of the right orbital region of the face. Computed tomography of the sinuses revealed shadow in sinuses with thickening of mucosa of the right paranasal sinuses. Lavage and aspirate from the sinuses revealed Rhizopus oryzae. Mucormycosis was successfully treated with amphotericin B (5 mg/kg/day) followed by ketoconazole (400 mg/day). Two months later the patient died from primary disease. Conclusion: In patients with acute leukemia who developed aplasia, febrile neutropenia, and pain in paranasal sinuses, fungal infection should be taken into consideration. New and non-invasive methods for taking samples from sinuses should be standardized in order to establish an early and accurate diagnosis of mucormycosis with the source in paranasal sinuses, and to start early treatment by a proper antifungal drug. Clear communication between physician and mycologist is critical to ensure proper and timely sampling of lavage and aspirate from sinuses and correct specimen processing when mucormycosis is suspected clinically.

[Favorable Outcome of Hepatosplenic Candidiasis in a Patient with Acute Leukemia].

INTRODUCTION: Acute leukemias treatment requires strong chemotherapy. Patients that develop bone marrow aplasia become immunocompromised, thus becoming liable to bacterial and fungal infections. Fungal infections caused by Candida are frequent. Hepatosplenic candidiasis (HSC) is a frequent consequence of invasive candidiasis which is clinically presented with prolonged febrility unresponsive to antibiotics. CASE OUTLINE: A 53-year-old patient with acute myeloid leukemia was submitted to standard chemotherapy "3+7" regimen (daunoblastine 80 mg i.v. on days 1 to 3, cytarabine 2 x 170 mg i.v. during 7 days) and achieved complete remission. However, during remission he developed febrility unresponsive to antibiotics. Computerised tomography (CT) of the abdomen showed multiple hypodense lesions within the liver and spleen. Haemocultures on fungi were negative. However, seroconversion of biomarkers for invasive fungal infection (FI) (Candida and Aspergillus antigen/Ag and antibody/Ab) indicated possible HSC. Only high positivity of anti-Candida IgG antibodies, positivity of mannan and CT finding we regarded sufficient for the diagnosis and antimycotic therapy.Three months of treatment with different antimycotics were necessary for complete disappearance of both clinical symptoms and CT findings. CONCLUSION: In patients with prolonged febrile neutropenia IFI has to be strongly suspected. If imaging techniques show multiple hypodense lesions within liver and spleen, HSC has to be taken seriously into consideration. We believe that, along with CT finding, positive laboratory Candida biomarkers (mannan and IgG antibodies) should be considered sufficient for"probable HSC" and commencement of antifungal therapy, which must be long enough, i.e. until complete disappearance of clinical symptoms and CT findings are achieved.

Acute Myocardial Infarction during Induction Chemotherapy for Acute MLL t(4;11) Leukemia with Lineage Switch and Extreme Leukocytosis.

INTRODUCTION: In patients with acute leukemias hemorrhage is the most frequent problem. Vein thrombotic events may appear rarely but arterial thromboses are exceptionally rare. We present a patient with acute leukemia and bilateral deep leg vein thrombosis who developed an acute myocardial infarction (AMI) during induction chemotherapy. The etiology and treatment of AMI in patients with acute leukemia, which is a rare occurrence, is discussed. CASE OUTLINE: In April of 2012 a 37-year-old male presented with bilateral deep leg vein thrombosis and malaise. Laboratory data were as follows: Hb 118 g/L, WBC 354 x 10(9)/L (with 91% blasts in differential leukocyte count), platelets 60x109/L. Bone marrow aspirate and immunophenotype revealed the presence of acute lymphoblastic leukemia. Cytogenetic analysis was as follows: 46,XY,t(4;11)(q21:q23) [2]/62-82,XYt(4;11)[18]. Molecular analysis showed MLL-AF4 rearrangement. The patient was on low molecular weight heparin and combined chemotherapy according to protocol HyperCVAD. On day 10 after chemotherapy he got chest pain. Three days later AMI was diagnosed (creatine kinase 66 U/L, CK-MB 13U/L, troponin 1.19 µg/L). Electrocardiogram showed the ST elevation in leads D1, D2, aVL, V5 and V6 and "micro q" in D1. On echocardiography, hypokinesia of the left ventricle and ejection fraction of 39% was found. After recovering from AMI and restoring left ventricle ejection fraction to 59%, second course of HyperCVAD was given. The control bone marrow aspirate showed 88% of blasts but with monoblastic appearance. Flow cytometry confirmed a lineage switch from lymphoblasts to monoblasts. In further course of the disease he was treated with a variety of chemotherapeutic combinations without achieving remission. Eventually, palliative chemotherapy was administered to reduce the bulk of blasts. He died five months after the initial diagnosis. CONCLUSION: AMI in young adults with acute leukemia is a very rare complication which may occur in patients with very high white blood cell count in addition with presence of a CD56 adhesion molecule and other concomitant thrombophilic factors. The treatment of AMI in patients with acute leukemias should include antiplatelet and anticoagulant therapy, even with more aggressive methods depending on patient's age and clinical risk assessment.

Thrombotic events in acute promyelocytic leukemia.

INTRODUCTION: Thrombotic events (TE) appear to be more common in acute promyelocytic leukemia (APL) than in other acute leukemias, with reported prevalence ranging from 2 to 10-15%. MATERIALS AND METHODS: We retrospectively analyzed the data on TE appearance in 63 APL patients. RESULTS: TE occured in 13 (20.6%) cases, four arterial (6.3%) and nine venous (14.3%). TE were more frequently diagnosed after initiation of weekly D-dimer monitoring (7 TE during 20 months vs 6 during 76 months, P=0.032). Patients with and without venous thrombosis were significantly different regarding female/male ratio (P=0.046), PT (P=0.022), aPTT (P=0.044), ISTH DIC score (P=0.001), bcr3 (P=0.02) and FLT3-ITD (P=0.028) mutation. The most significant risk factor for venous TE occurrence in multivariate analysis was FLT3-ITD mutation (P=0.034). PAI-1 4G/4G polymorphism was five times more frequent in patients with venous TE than without it (P=0.05). Regarding risk factors for arterial TE we failed to identify any. CONCLUSIONS: We have demonstrated that APL-related TE rate is higher than previously reported and that weekly D-dimer monitoring might help to identify patients with silent thrombosis. Moreover, our study suggests a possible relationship between venous TE occurrence and several laboratory findings (PT, aPTT, ISTH DIC score, bcr3 isoform, FLT3-ITD mutation and PAI 4G/4G). Prophylactic use of heparin might be considered in patients with ISTH DIC score<5, bcr3 isoform, FLT3-ITD mutation and PAI 4G/4G.

Comparison of two laboratory assays in monitoring the efficacy of different prophylaxis regimens for severe haemophilia.

BACKGROUND: The goal of this study was to compare the validity of two laboratory assays, rotation thromboelastometry (ROTEM) and endogenous thrombin potential (ETP), in monitoring and evaluating different prophylactic treatment regimens in patients with severe haemophilia. METHODS: Twenty adult patients with severe haemophilia were divided into three groups according to treatment regimen with concentrate of factor (F) VIII/IX: full-dose prophylaxis (5 patients), intermediate-dose prophylaxis (5 patients), and on demand treatment (10 patients). RESULTS: The ROTEM for the group treated with full-dose prophylaxis was significantly lower than ROTEM for the group treated with intermediate-dose prophylaxis (p = 0.025). Among the patients given full-dose prophylaxis, 40% (2 patients) had prolonged ROTEM after 3 months of treatment, while among those given intermediate-dose prophylaxis all patients (100%, 5 patients) had prolonged ROTEM (p = 0.038). The ETP was significantly improved after 3 months of full-dose in comparison with intermediate-dose prophylaxis (p = 0.042). CONCLUSIONS: ROTEM and ETP are useful laboratory assays for monitoring efficacy of different prophylaxis regimens with concentrate of FVIII/IX in patients with severe haemophilia, helping in making decisions regarding optimal dose-regimen prophylaxis.

The effect of paraprotein on platelet aggregation.

BACKGROUND: Some patients with paraproteinemia have platelet aggregation disorders and the aim of this study was to examine disturbance of platelet aggregation in healthy blood donors by isolated paraprotein in vitro. METHODS: Using Rivanol, paraprotein was separated from the serum of ten patients with paraproteinemia, who had decreased platelet aggregation with several inducers. Platelet aggregation in ten healthy donors was measured with and without addition of the isolated induced paraprotein. The test was repeated with added human immunoglobulins for intravenous use. RESULTS: Average of maximal levels of platelet aggregation has been significantly decreased in plasma rich in platelets (PRP) of healthy donors after addition of paraprotein when inducers are used: adenosine diphosphate (ADP) (P = 0.007), collagen (COL) (P = 0.008), ristocetin (RIS) (P = 0.001), and epinephrine (EPI) (P = 0.002). Average of latent time of platelet aggregation was significantly prolonged in healthy donors after addition of paraprotein with inducers: COL (P = 0.008), RIS (P = 0.008) and EPI (P = 0.006) while addition of human immunoglobulins caused no change in platelet aggregation. In comparison, when human immunoglobulins were added, maximal platelet aggregation and latent time did not change significantly. Paraprotein isolated from patients with paraproteinamia, who had decrease platelet aggregation, had significantly decreased platelet aggregation when added to PRP of healthy donors, in vitro. CONCLUSION: Platelet aggregation was not significantly changed was confirmed with addition of human immunoglobulins.

Proven invasive pulmonary mucormycosis successfully treated with amphotericin B and surgery in patient with acute myeloblastic leukemia: a case report.

INTRODUCTION: Invasive mucormycosis (zygomycosis) is the third most frequent fungal infection in patients with hematologic malignancies. It often results in a fatal outcome mainly due to the difficulty of early diagnosis and its resistance to antimycotics. CASE PRESENTATION: A 52-year-old Caucasian man was diagnosed with acute myeloblastic leukemia. Following the induction chemotherapy he developed febrile neutropenia. Meropenem (3×1000mg/day) was introduced empirically. A chest computed tomography showed soft-tissue consolidation change in his right upper lobe. A bronchoscopy was performed and the histology indicated invasive pulmonary aspergillosis based on fungal hypha detection. Also, high risk patients are routinely screened for invasive fungal infections using commercially available serological enzyme-linked immunosorbent assay tests: galactomannan and mannan (Bio-Rad, France), as well as anti-Aspergillus immunoglobulin G and/or immunoglobulin M and anti-Candida immunoglobulin G and/or immunoglobulin M antibodies (Virion-Serion, Germany). Galactomannan showed low positivity and voriconazole therapy (2×400mg/first day; 2×300mg/following days) was implemented. The patient became afebrile and a partial remission of disease was established. After 2 months, the patient developed a fever and a chest multi-slice computed tomography showed soft-tissue mass compressing his upper right bronchus. Voriconazole (2×400mg/first day; 2×300mg/following days) was reintroduced and bronchoscopy was repeated. Histologic examination of the new specimen was done, as well as a revision of the earlier samples in the reference laboratory and the diagnosis was switched to invasive pulmonary mucormycosis. The treatment was changed to amphotericin B colloidal dispersion (1×400mg/day). The complete remission of acute myeloblastic leukemia was verified after 2 months. During his immunerestitution, a high positivity of the anti-Aspergillus immunoglobulin M antibodies was found in a single serum sample and pulmonary radiography was unchanged. A lobectomy of his right upper pulmonary lobe was done and the mycology culture of the lung tissue sample revealed Rhizopus oryzae. He remained in complete remission for more than 1 year. CONCLUSIONS: Invasive mucormycosis was successfully treated with amphotericin B, surgery and secondary itraconazole prophylaxis. As a rare disease invasive mucormycosis is not well understood by the medical community and therefore an improvement of education about prevention, diagnosis and treatment of invasive mucormycosis is necessary.

Complex patterns of chromosome 11 aberrations in myeloid malignancies target CBL, MLL, DDB1 and LMO2.

Exome sequencing of primary tumors identifies complex somatic mutation patterns. Assignment of relevance of individual somatic mutations is difficult and poses the next challenge for interpretation of next generation sequencing data. Here we present an approach how exome sequencing in combination with SNP microarray data may identify targets of chromosomal aberrations in myeloid malignancies. The rationale of this approach is that hotspots of chromosomal aberrations might also harbor point mutations in the target genes of deletions, gains or uniparental disomies (UPDs). Chromosome 11 is a frequent target of lesions in myeloid malignancies. Therefore, we studied chromosome 11 in a total of 813 samples from 773 individual patients with different myeloid malignancies by SNP microarrays and complemented the data with exome sequencing in selected cases exhibiting chromosome 11 defects. We found gains, losses and UPDs of chromosome 11 in 52 of the 813 samples (6.4%). Chromosome 11q UPDs frequently associated with mutations of CBL. In one patient the 11qUPD amplified somatic mutations in both CBL and the DNA repair gene DDB1. A duplication within MLL exon 3 was detected in another patient with 11qUPD. We identified several common deleted regions (CDR) on chromosome 11. One of the CDRs associated with de novo acute myeloid leukemia (P=0.013). One patient with a deletion at the LMO2 locus harbored an additional point mutation on the other allele indicating that LMO2 might be a tumor suppressor frequently targeted by 11p deletions. Our chromosome-centered analysis indicates that chromosome 11 contains a number of tumor suppressor genes and that the role of this chromosome in myeloid malignancies is more complex than previously recognized.

Dipeptidyl peptidase IV: serum activity and expression on lymphocytes in different hematological malignancies.

The aim of this research was to determine the serum dipeptidyl peptidase IV (DPPIV) activity as well as the percentages of CD26 + lymphocytes and CD26 + overall white blood cells in patients with hematological malignancies: non-Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL), leukemia, plasmacytoma and multiple myeloma, and in healthy individuals. Data from our study showed significantly decreased serum DPPIV activity and a significant decrease in the percentage of: CD26 + lymphocytes, CD26 + overall white blood cells and lymphocytes in patients with NHL in comparison to healthy controls. Patients with leukemia had a statistically significant lower activity of DPPIV in serum and significant decrease in the percentage of CD26 + lymphocytes in relation to healthy controls. Furthermore, significantly decreased DPPIV serum activity associated with a significantly reduced percentage of CD26 + overall white blood cells and percentage of lymphocytes was found in patients with multiple myeloma when compared to the healthy control group. The obtained results indicate that immune disturbances that can occur in hematological malignancies might be related to the decreased expression and activity of CD26/DPPIV that we observed.

International Society of Thrombosis and Hemostasis Scoring System for disseminated intravascular coagulation ≥ 6: a new predictor of hemorrhagic early death in acute promyelocytic leukemia.

High-hemorrhagic early death (ED) rate is a major impediment in the managing of acute promyelocytic leukemia (APL). In our group of 56 newly diagnosed APL patients, ED occurred in 12 subjects, due to endocranial bleeding (8/12), differentiation syndrome (2/12), or infection (2/12). Predictors of hemorrhagic ED were as follows: white blood cells count ≥ 20 × 10(9)/L (P = 0.002337), Eastern cooperative oncology group performance status ≥ 3 (P = 0.00173), fibrinogen level <2 g/L (P = 0.004907), prothrombin time <50% (P = 0.0124), and International Society of Thrombosis and Hemostasis Scoring System for disseminated intravascular coagulation (ISTH DIC score) ≥ 6 (P = 0.00741). Multivariate analysis indicated ISTH DIC score ≥ 6 to be the most significant predictor for hemorrhagic ED (P = 0.008). The main finding of this study is that simple coagulation-related tests, performed on hospital admission and combined in the ISTH DIC score, might help to identify patients at high risk for fatal bleeding needing more aggressive supportive measures.

Prognostic risk score for the survival of elderly patients with acute myeloid leukaemia comprising comorbidities.

Using various risk factor scores, we aimed to identify a subset of elderly patients with acute myeloid leukaemia (AML) for whom it was possible to assess the prognosis. We also aimed to develop a novel prognostic score system. This single centre study involved 102 patients of ≥60 years of age with non-promyelocytic AML. The adverse cytogenetic risk group appeared as the most significant independent prognostic factor for overall survival (OS). Our prognostic scoring system was developed after analysing prognostic risk factors and was applied for patients with favourable and intermediate (I and II) cytogenetic risk groups: age <65 years of age, normal lactate dehydrogenase (LDH) and a comorbidity score obtained applying the haematopoietic cell transplantation-specific comorbidity index (HCT-CI) < 3 = 0 points, in which age ≥65 years = 1 point and an elevated LDH score and HCT-CI ≥3 = 2 points. According to this prognostic model, patients without adverse cytogenetics were classified into three risk groups: favourable = 0-2 points, intermediate = 3-4 points and poor = > 4 points. The OS between these groups was highly significant (p < 0.001). The prognostic model developed in this study may refine the prognosis procedure of elderly AML patients without an adverse karyotype regarding OS, thereby guiding the treatment approach.

Risk factors for vancomycin-resistant Enterococcus colonization in hematologic patients.

BACKGROUND/AIM: Vancomycin-resistant Enterococci (VRE) is one of the most important hospital pathogens. The aim of the study was to evaluate VRE colonization in patients hospitalized at the Hematology Intensive Care Unit, as well as the associated risk factors. METHODS: A prospective cohort study involved 70 patients hospitalized at the Intensive Care Unit (ICU), Clinic for Hematology, Clinical Center of Serbia, Belgrade, during 3 months. Baseline demographic data, data about antibiotic usage and other risk factors for VRE colonization during the present and previous hospitalizations (within 6 months) were recorded for each patient using the questionnaire. Feces or rectal swab was collected for culture from patients on admission and at discharge in case when VRE was not isolated on admission. Enterococci were isolated by standard microbiological methods. Isolate sensitivity was tested by disk-diffusion test using 30 microg/mL (BBL) Vancomycin plates according to the Clinical and Laboratory Standards Institute (CLSI) standard. RESULTS: Analysing results showed that 7% of the patients had been already colonized with VRE upon ICU admission. The rate of VRE colonization during present hospitalization was 41.5%. Univariate logistic regression demonstrated the statistically significant differences in diagnosis, length of present stay, use of aminoglycosides and piperacillin/tazobactam in present hospitalization, duration of use of carbapenem and piperacillin/tazobactam in present hospitalization between the VRE-colonized and non-colonized patients. Acute myeloid leukemia (AML), use of carbapenem in previous hospitalization and duration of use of piperacillin/tazobactam in present hospitalization were independent risk factors for VRE-colonized patients according to multivariate logistic regression. CONCLUSION: VRE colonization rate was high among the patients admitted to hematology ICU. Rational use of antibiotics and active surveillance may be helpful preventive measures against the development of bacterial resistance to antimicrobial agents.