The Role of Thalidomide and Its Analogs in the Treatment of Hereditary Hemorrhagic Telangiectasia: A Systematic Review.

Background: Hereditary hemorrhagic telangiectasia (HHT) is a disease characterized by arteriovenous malformations and telangiectases, in which the endothelium and immune system play a role in the pathophysiology. Therefore, treatments with antiangiogenic properties which are also regarded as immunomodulators were demonstrated to play an important role in treatment. This systematic review aimed to gather the accumulated information of the use of thalidomide and its analogs in the treatment of HHT. Methods: In this systematic review, publications that were published up to March 2024 and met the inclusion criteria were compiled using the keywords 'thalidomide', 'lenalidomide', 'pomalidomide', 'immunomodulatory drugs' and 'HHT' in Medline and Scholars databases. Results: A total of 53 articles were evaluated and 15 were included in the study. Thalidomide was the predominant used agent and was observed to be used in patients with ages ranging from 37 to 77 years, with doses ranging from 50 to 200 mg daily, and the mean follow-up period was observed to be 6-60 months. Assessments regarding efficacy were based on the epistaxis severity score (ESS), hemoglobin level, and transfusion independence. While thalidomide showed significant efficacy, it also had an adverse event rate of any severity of up to 85% of patients. Use of lenalidomide to control bleeding in HHT was reported in a single case report, while the use of pomalidomide was observed to be investigated in Phase 1 and Phase 2 studies in patients aged 48 to 70 years, with doses ranging from 1 to 5 mg daily for 6-24 months. This treatment was reported to provide significant improvement in hemoglobin levels and ESS. Adverse events of any severity were observed at a frequency of 60-66%. Conclusions: Antiangiogenic agents such as thalidomide, lenalidomide, and pomalidomide may be effective in managing HHT. However, further studies are needed to optimize the timing, dose, and sequence.

Myeloproliferative Neoplasm Symptom Assessment Total Symptom Score (MPN-SAF TSS) in Chronic Myeloproliferative Neoplasms with Relation to Genetic Burden and Thrombosis

The Myeloproliferative Neoplasm Symptom Assessment Total Symptom Score (MPN-SAF TSS) is a surrogate marker for symptom evaluation in chronic myeloproliferative neoplasms (MPNs). However, insufficient data are available regarding the relationship among the MPN-SAF TSS, JAK2 mutation allele burden, and thrombosis. In this retrospective analysis, we aimed to determine the genetic burdens, clinical features, and relationships with MPN-SAF TSS in MPN patients. One hundred thirty JAK2V617F-positive patients with MPNs were included in our study. We calculated the MPN-SAF TSS for all patients and compared it with their clinical characteristics. Patients with higher JAK2V617F mutation allele burden had higher MPN-SAF TSS values (p=0.008). Patients with thrombosis had higher MPN-SAF TSS than patients without thrombosis (p=0.003). The mean MPN-SAF TSS was higher in patients with primary myelofibrosis compared to those with polycythemia vera and essential thrombocythemia. Thrombosis was associated with increased symptom severity in several domains, including fatigue, abdominal discomfort, inactivity, night sweats, pruritus, weight loss, and early satiety. Additionally, an increase in JAK2 allele burden was observed with higher symptom scores. The MPN-SAF TSS proved to be a reliable tool for assessing symptom burden in Turkish MPN patients. Furthermore, the significant association between thrombosis occurrence and symptom severity suggests that thrombotic events may contribute to symptom development. Notably, increasing JAK2 allele burden was correlated with more severe symptoms, highlighting its potential role in predicting disease burden. This study emphasizes the importance of symptom assessment in MPN patients and supports the incorporation of the MPN-SAF TSS in routine clinical practice to enhance patient care and management.

Management of Primary Immune Thrombocytopenia: Turkish Modified Delphi-Based Consensus Statement for Special Considerations

Objective: Primary immune thrombocytopenia (ITP) is an acquired disorder of platelets with a complex and unclear mechanism of increased immune destruction or impaired production of platelets. While the management of ITP is evolving, there is still a need for guidance, particularly in certain circumstances such as pregnancy, emergencies, or patients requiring co-medications. We aimed to determine the tendencies of hematologists in Türkiye in the event of such special considerations. Materials and Methods: Applying a modified Delphi method, the Turkish National ITP Working Group, founded under the auspices of the Turkish Society of Hematology, developed a questionnaire consisting of statements regarding pregnancy, emergencies, and circumstances requiring co-treatment with antiaggregants or anticoagulants. A total of 107 hematologists working in university or state hospitals voted for their agreement or disagreement with the statements for two sequential rounds. Results: The participating hematologists reached an agreement on starting treatment for pregnant patients with platelets of less than 30x109/L and delivery either vaginally or by cesarean section being safe at platelet counts above 50x109/L. For emergencies and the rescue management of ITP, the panel agreed against the use of high-dose corticosteroids alone, preferring combinations with transfusions or intravenous immunoglobulin. For patients who require interventions, platelet counts of >50x109/L were regarded as safe for low-risk procedures as well as co-treatment with antiplatelets or anticoagulants. Conclusion: As the National ITP Study Group, we have observed the need to increase the practice guidance regarding patients with primary ITP requiring additional treatments including invasive interventions and co-treatments for coagulation. Decisions on the management of ITP during pregnancy should be individualized. There is a lack of consensus on the thresholds of platelet counts as well as co-morbidities and co-medications. This lack of consensus may be due to variations in practices.

Management of Adult Primary Immune Thrombocytopenia: Delphi-Based Consensus Recommendations

Objective: Primary immune thrombocytopenia (pITP) is an acquired autoimmune disorder related to the increased destruction and/or impaired production of platelets. Its diagnosis and management are challenging and require expertise and the interpretation of international consensus reports and guidelines with national variations in availability. We aimed to assess the agreement of hematologists in Türkiye on certain aspects of both first-line and second-line management of patients with pITP. Materials and Methods: Applying a modified Delphi method, the Turkish National ITP Working Group (14 steering committee members), founded under the auspices of the Turkish Society of Hematology, developed a 21-item questionnaire consisting of statements regarding the first-line and second-line treatment of pITP. A total of 107 adult hematologists working in either university or state hospitals voted for their agreement or disagreement with the statements in two consecutive rounds. Results: The participants reached consensus on the use of corticosteroids as first-line treatment and with limited duration. Methylprednisolone was the corticosteroid of choice rather than dexamethasone. Use of intravenous immunoglobulin was not preferred for patients without bleeding. It was also agreed that thrombopoietin receptor antagonists (TPO-RAs) or rituximab should be recommended as second-line treatment and that splenectomy could be considered 12-24 months after diagnosis in patients with chronic pITP. Conclusion: The optimization of the dose and duration of TPO-RAs in addition to corticosteroids is necessary to improve the management of patients with pITP.

Immune Thrombotic Thrombocytopenic Purpura in Elderly Patients: The Roles of PLASMIC and French Scores

Objective: In recent years, new developments have been incorporated into daily practice in the management of immune thrombotic thrombocytopenic purpura (iTTP). In particular, clinical scoring systems could help clinicians with clinical decision-making and early recognition. However, older patients frequently present with more organ involvement and in unusual ways. The ways in which age could affect these clinical prediction scoring systems remain unclear. We evaluated the use of PLASMIC and French scores in patients over 60 years of age. Materials and Methods: We performed a retrospective cross-sectional analysis of patients over 60 years of age with a presumptive diagnosis of iTTP between 2014 and 2022 at 10 centers. We calculated PLASMIC and French scores and compared our data with a single-center analysis of younger patients presenting with thrombotic microangiopathy. Results: Our study included 30 patients over 60 years of age and a control group of 28 patients younger than 60 years. The diagnostic sensitivity and specificity of a French score of ≥1 were lower in older patients compared to the control group (78.9% vs. 100% and 18.2% vs. 57.1%, respectively). The diagnostic sensitivity and specificity of a PLASMIC score of ≥5 were 100% vs. 95% and 27.3% vs. 100% for the study group and control group, respectively. Our study showed a higher mortality rate in older patients compared to the control group (30% vs. 7.1%, p=0.043). Conclusion: For a limited number of patients (n=6), our results showed that rituximab can reduce mortality. Given that the reliability of clinical prediction scores for iTTP in older patients may be lower, more caution must be undertaken in interpreting their results.

Morphologic evaluation of megakaryocytes in immune thrombocytopenia patients older than 80 years.

OBJECTIVE: In immune thrombocytopenia (ITP), which is a common acquired bleeding disorder, cytotoxic T-cell-mediated cellular immune response against both circulating platelets and bone marrow megakaryocytes are the most important mechanisms in the pathogenesis. METHODS: In our study, we evaluated the features of 33 patients with ITP, over 80 years of age. RESULTS: The median age of the patients was 90, 15 patients were female (45.4%). The mean platelet count of the patients was 39×109/L and the mean mean platelet volume was 10,33fL. Twelve patients had a target thrombocyte count greater than 30×109/L, while 20 patients had a target platelet count of 75×109/L or greater with an absolute indication of antiaggregation. In the environmental spread, 18 dysplasia findings were observed. CONCLUSION: Morphologic observations suggesting dysplasia including micromegakaryocytes and a non-dysplastic but dysmegakaryopoietic finding, multiple segmented nuclei may be related to the degree of thrombocytopenia and response to treatment. Likewise, nondysplastic features including immature forms, emperipolesis, bare nucleus, hypolobulation, and hypersegmented nucleus were related to the degree of thrombocytopenia.

Successful pregnancy and delivery management in a patient with Bernard Soulier Syndrome.

Bernard Soulier Syndrome (BSS) is an inherited bleeding disorder characterized by macrothrombocytopenia and absence of ristocetin-induced platelet aggregation. Clinical findings vary from person to person. Most of the patients are diagnosed with muco-cutaneous bleeding such as purpura, epistaxis and gingival bleeding in early childhood. Few pregnant women with BSS are described in the literature. Management of thrombocytopenia during pregnancy and delivery requires a multidisciplinary approach. The family should be warned about the potentially life-threatening bleeding during pregnancy and the delivery and the decision about mode of delivery should be individualised, involving discussion with patient and multidisciplinary team.

International Forum: The Turkish perspective on apheresis activity: The Turkish apheresis registry report.

Therapeutic apheresis is an extracorporeal treatment that selectively removes abnormal cells or harmful substances in the blood that are associated with or cause certain diseases. During the last decades the application of therapeutic apheresis has expanded to a broad spectrum of hematological and non-hematological diseases due to various studies on the clinical efficacy of this procedure. In this context there are more than 30 centers performing therapeutic apheresis and registered in the apheresis database in Turkey. Herein, we, The Turkish Apheresis Registry, aimed to analyze some key articles published so far from Turkey regarding the use of apheresis for various indications.

Incidence and predisposing factors of infection in patients treated with hypomethylating agents.

OBJECTIVE: Hypomethylating agents may have adverse effects such as cytopenias, cytopenia associated infections and fatality due to infections despite their favorable effects in the treatment of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML). The infection prophylaxis approach is based on expert opinions and real-life experiences. Hence, we aimed to reveal the frequence of infections, predisposing factors of infection and to analyse infection attributable mortality in patients with high-risk MDS, CMML and AML who received hypomethylating agents in our center where routine infection prophylaxis is not applied. MATERIAL-METHOD: 43 adult patients with AML or high-risk MDS or CMML who received HMA ≥ 2 consecutive cycles from January 2014 to December 2020 were enrolled in the study. RESULTS: 43 patients and 173 treatment cycles were analyzed. The median age was 72 years and 61.3 % of patients were males. The distribution of the patients' diagnoses was; AML in 15 patients (34.9 %), high risk MDS in 20 patients (46.5 %), AML with myelodysplasia-related changes in 5 patients (11.6 %) and CMML in 3 patients (7 %). 38 infection events (21.9 %) occurred in 173 treatment cycles. 86.9 % (33 cycles) and 2.6 % (1 cycle) of infected cycles were bacterial and viral infections, respectively and 10.5 % (4 cycles) were bacterial and fungal concurrently. The most common origin of the infection was respiratory system. Hemoglobin count was lower and CRP level was higher at the beginning of the infected cycles significantly (p values were 0.002 and 0.012, respectively). Requirement of red blood cell and platelet transfusions were found to be significantly increased in the infected cycles (p values were 0.000 and 0.001, respectively). While > 4 cycles of treatment and increased platelet count were found to be protective against infection, > 6 points of Charlson Comorbidity Index (CCI) were found to increase the risk of infection. The median survival was 7.8 months in non-infected cycles while 6.83 months in infected cycles. This difference was not statistically significant (p value was 0.077). DISCUSSION: The prevention and management of infections and infection-related deaths in patients treated with HMAs is crucial. Therefore, patients with a lower platelet count or a CCI score of > 6 may be candidates for infection prophylaxis when exposed to HMAs.

Castleman Disease: A Multicenter Case Series from Turkey

Objective: Castleman disease (CD) is a rare disease also known as angiofollicular lymph node hyperplasia. The two main histological subtypes are the hyaline vascular and plasma cell variants. It is further classified as unicentric CD (UCD) or multicentric CD (MCD) according to the anatomical distribution of the disease and the number of lymph nodes involved. The aim of this multicenter study was to evaluate all cases of CD identified to date in Turkey to set up a national registry to improve the early recognition, treatment, and follow-up of CD. Materials and Methods: Both adult (n=130) and pediatric (n=10) patients with lymph node or involved field biopsy results reported as CD were included in the study. Patients' demographic information, clinical and laboratory characteristics, imaging study results, treatment strategies, and clinical outcomes were evaluated retrospectively. Results: A total of 140 patients (69 male and 71 female) with a diagnosis of UCD (n=73) or MCD (n=67) were included. The mean age was 39 years in the UCD group and 47 years in the MCD group. Female patients were more common in the UCD group. The most common histological subtype was hyaline vascular for both UCD and MCD patients. Asymptomatic patients were more common in the UCD group. Anemia, elevations of acute phase reactants, and hypoalbuminemia were more common in the MCD group. The most commonly used treatment strategies for UCD were surgical excision, rituximab, and radiotherapy, respectively. All UCD patients were alive at a median of 19.5 months of follow-up. The most commonly used treatment strategies for MCD were methyl prednisolone, R-CHOP, R-CVP, and rituximab. Thirteen MCD patients had died at a median of 34 months of follow-up. Conclusion: This study is important in presenting the patient characteristics and treatment strategies for CD from Turkey, with the potential of increasing awareness about CD. Treatment data may help in making decisions, particularly in countries that do not have access to siltuximab. However, larger prospective studies are needed to make definitive conclusions.

Results of multicenter registry for patients with inherited factor VII deficiency in Turkey.

INTRODUCTION: Inherited factor VII (FVII) deficiency (FVIID) is the most common of inherited rare bleeding disorders. Other determinants of clinical severity apart from FVII level (FVIIL) include genetic and environmental factors. We aimed to identify the cut-off FVIILs for general and severe bleedings in patients with FVIID by using an online national registry system including clinical, laboratory, and demographic characteristics of patients. METHODS: Demographic, clinical, and laboratory data of patients with FVIID extracted from the national database, constituted by the Turkish Society of Hematology, were examined. Bleeding phenotypes, general characteristics, and laboratory features were assessed in terms of FVIILs. Bleeding rates and prophylaxis during special procedures/interventions were also recorded. RESULTS: Data from 197 patients showed that 46.2% of patients had FVIIL< 10%. Most bleeds were of mucosal origin (67.7%), and severe bleeds tended to occur in younger patients (median age: 15 (IQR:6-29)). Cut-off FVIILs for all and severe bleeds were 16.5% and 7.5%, respectively. The major reason for long-term prophylaxis was observed as central nervous system bleeding (80%). CONCLUSION: Our data are consistent with most of the published literature in terms of cut-off FVIIL for bleeding, as well as reasons for prophylaxis, showing both an increased severity of bleeding and younger age at diagnosis with decreasing FVIIL. However, in order to offer a classification similar to that in Hemophilia A or B, data of a larger cohort with information about environmental and genetic factors are required.

Efficacy and Safety of Ibrutinib Therapy in Patients with Chronic Lymphocytic Leukemia: Retrospective Analysis of Real-Life Data

Objective: This study aimed to retrospectively evaluate the efficacy, safety, and survival outcome of single-agent ibrutinib therapy in chronic lymphocytic leukemia patients. Materials and Methods: A total of 136 patients (mean age ± standard deviation: 64.6±10.3 years, 66.9% males) who had received at least one dose of ibrutinib were included in this retrospective multicenter, noninterventional hospital-registry study conducted at 33 centers across Turkey. Data on patient demographics, baseline characteristics, laboratory findings, and leukemia-cell cytogenetics were retrieved. Treatment response, survival outcome including overall survival (OS) and progression-free survival (PFS), and safety data were analyzed. Results: Overall, 36.7% of patients were categorized as Eastern Cooperative Oncology Group (ECOG) class 2-3, while 44.9% were in Rai stage 4. Fluorescence in situ hybridization revealed the presence of del(17p) in 39.8% of the patients. Patients received a median of 2.0 (range: 0-7) lines of pre-ibrutinib therapy. Median duration of therapy was 8.8 months (range: 0.4-58.0 months). The 1-year PFS and OS rates were 82.2% and 84.6%, respectively, while median PFS time was 30.0 (standard error, 95% confidence interval: 5.1, 20.0-40.0) months and median OS time was 37.9 (3.2, 31.5-44.2) months. Treatment response (complete or partial response), PFS time, and OS time were better with 0-2 lines versus 3-7 lines of prior therapy (p<0.001, p=0.001, and p<0.001, respectively), with ECOG class 0-1 versus class 2-3 (p=0.006, p=0.011, and p=0.001, respectively), and with Rai stage 0-2 versus 3-4 (p=0.002, p=0.001, and p=0.002, respectively). No significant difference was noted in treatment response rates or survival outcome with respect to the presence of comorbidity, bulky disease, or del(17p). While 176 adverse events (AEs) were reported in 74 (54.4%) patients, 46 of those 176 AEs were grade 3-4, including pneumonia (n=12), neutropenia (n=11), anemia (n=5), thrombocytopenia (n=5), and fever (n=5). Conclusion: This real-life analysis confirms the favorable efficacy and safety profile of long-term ibrutinib treatment while emphasizing the potential adverse impacts of poorer ECOG performance status, heavy treatment prior to ibrutinib, and advanced Rai stage on patient compliance, treatment response, and survival outcomes.

Sarcopenia in Hodgkin's lymphoma evaluated with 18-FDG PET/CT, focus on age, performance, and treatment.

Sarcopenia is defined as a progressive and generalized muscle disorder associated with certain physiological and pathological conditions. We aimed to evaluate the prevalence of sarcopenia in patients with HL using 18-fluoro deoxyglucose (FDG) PET/CT, which would provide a data of muscle mass with the CT compartment and also data of muscle metabolism with the 18-FDG compartment of the imaging modality. Fifty-nine patients diagnosed with HL were included in the study. PET/CT images before and after treatment were evaluated with regard to lumbar muscle mass and metabolism. Mean lumbar muscle evaluation with CT before treatment was 92, 40 HU, and after treatment was 89, 41 HU. Mean metabolic tumor volume (MTV) evaluated with FDG PET before treatment was 4, 13 mm3 while after treatment was 4, 10 mm3. The lumbar muscle mass in terms of HU which was evaluated with CT was observed to be decreased after treatment. Likewise, the metabolic evaluation was observed to be also decreased after treatment. Despite the decline in muscle mass after treatment in the whole group, this decline was particularly observed in the better initial performance group. In patients with BMI > 32, there was a significant decline in muscle mass. Abdominal nodal involvement was related with poorer muscle mass and quality. In HL care, particular attention should be given to patients who are younger and with better physical condition in terms of preserving the muscle reserves and preventing sarcopenia.

Economic analysis of oral posaconazole prophylaxis in acute myeloid leukemia during remission induction in Turkey.

OBJECTIVE: Invasive fungal infections (IFI) are important and trending causes of mortality in patients with acute leukemia, especially during the remission induction. METHODS: In this study, 225 patients who were diagnosed with acute myeloid leukemia (AML) and undergoing intensive treatment for remission induction were enrolled in a retrospective manner. RESULTS: Within the whole group, which consisted of 225 patients, 90 patients received prophylactic antifungal treatment (PAT) (40%), while 135 patients did not (60%) receive. The mean cost of hospitalization was 9.151,6 (2.872,6-20.483,3) US dollars. Gender distribution and mean ages of groups were similar. One hundred fourteen patients not on PAT (84.4%) and five patients on PAT (5.5%) received intravenous antifungal treatment. Thirty-two of the patients who were not on PAT (23.7%) and 11 of the patients on PAT died during remission induction (12.22%). The mean day of the hospitalization was 22.61 days for the patients on PAT and 33.89 days for the patients who were not on PAT. In patients on PAT, the mean number of transfused platelet units was six (0-9), while 12.51 (4-43) units for patients who were not on PAT. CONCLUSION: In our study, the oral suspension form of posaconazole was observed to be cost-effective to prevent IFI with a significant decrease in mortality during remission induction treatment.

The Incidence of Venous Thromboembolism and Impact on Survival in Hodgkin Lymphoma.

BACKGROUND: Thrombosis increase the acute and long-term morbidity and mortality in malignancy patients. We analyzed venous thromboembolism (VTE) in patients with Hodgkin lymphoma, the impact of VTE on survival, predisposing factors for VTE, and predicting value of Khorana and ThroLy score models. PATIENTS AND METHODS: We included 150 adult patients with Hodgkin lymphoma between January 2010 and 2018 at our university hospital. RESULTS: VTE was observed in 31 patients (20.7%). The types of VTE were 18 upper and 3 lower extremity deep vein thrombosis and 10 pulmonary embolism (1 with lower extremity deep vein thrombosis). Twenty-nine patients developed VTE during the treatment with a median time of episode as 5 months. In logistic regression analysis, a body mass index of >32 kg/m2, high fibrinogen levels, initial thrombocytosis and leukocytosis, splenic and extranodal involvement, presence of a central venous line, advanced stage, line of treatment status of thromboprophylaxis, VTE timing, and better Eastern Cooperative Oncology Group performance scores were observed to be related with VTE. Kaplan Meier survival analysis showed a negative impact of VTE on survival. Khorana and ThroLy risk assessment models were found predictive for VTE (P = .000 and P = .003, respectively), although only ThroLy score was associated with the survival. CONCLUSION: Thromboprophylaxis and precautions for VTE in patients with Hodgkin lymphoma according to validated risk assessment models can improve prognosis and quality of life owing to the impact of VTE on survival in the study.

Drug Induced Thrombotic Microangiopathy with Certolizumab Pegol

Background: Certolizumab pegol is used to treat ankylosing spondylitis, Crohn's disease, psoriatic arthritis, and rheumatoid arthritis. Unlike other monoclonal antibodies such as infliximab and adalimumab, certolizumab does not contain an Fc fraction and hence does not induce complement activation. In this report, we describe the case of a patient with thrombotic microangiopathy caused due to certolizumab pegol, with a brief description about the pathophysiological approach to thrombotic microangiopathy. Case Report: A-39-year-old man suffering from ankylosing spondylitis for the past 10 years presented with fatigue. He had been on certolizumab pegol treatment for 6 months, starting with 400 and 200 mg every 2 weeks. He had significant nonimmune hemolytic anemia and thrombocytopenia without a disseminated intravascular coagulopathy. Schistocytes were observed in more than 10% of the erythrocytes per field. Plasma exchange along with corticosteroid treatment was started. There was a dramatic improvement within a week, and after 10 sessions of plasma exchange, the patient was discharged on corticosteroids with a tapering plan. ADAMTS13 enzyme activity was determined to be normal. Conclusion: The development of drug-induced thrombotic microangiopathy may be either immune-mediated or dose-dependent toxicity-mediated Anti-drug antibodies and their immunological aspects are still unclear and yet to be elucidated.

Hypogammaglobulinemia and Poor Performance Status are Predisposing Factors for Vancomycin-Resistant Enterococcus Colonization in Patients with Hematological Malignancies.

OBJECTIVE: Vancomycin-resistant enterococci (VRE) are common pathogens of hospital-acquired infection. Long hospitalization periods, use of broad-spectrum antibiotics, and immunosuppression are major risks for VRE colonization. We aimed to evaluate patients' characteristics and factors that may contribute to VRE colonization. MATERIALS AND METHODS: Data of 66 patients with colonization and 112 patients without colonization who were hospitalized in the hematology clinic were collected. Hematological malignancies, preexisting gastrointestinal complaints, the presence of hypogammaglobulinemia at the time of diagnosis, complications like neutropenic enterocolitis (NEC), and Eastern Cooperative Oncology Group (ECOG) and Karnofsky performance statuses were recorded. RESULTS: Ages of the patients ranged between 19 and 95 years (mean: 55.99). Karnofsky and ECOG scores were statistically related to VRE colonization (p<0.000 and p<0.000), though only the Karnofsky score was significant based on logistic regression analysis. Almost all patients with acute leukemia (45 patients) had been on antibiotics (piperacillin-tazobactam, ceftazidime, and meropenem), while no patients with myelodysplastic syndrome, myeloma, or benign diseases and 2 patients with lymphoma and 1 with chronic myeloid leukemia were on antibiotics. Median time for colonization regardless of antibiotic use and diagnosis was 4.5 days (range: 3-11 days). In the VRE-colonized group, 40.9% of patients had NEC development, while in the non-colonized group, only 1.7% had NEC development. In the VRE-colonized group 46 patients (69.7%) and in the non-colonized group 27 patients (24.1%) had hypogammaglobulinemia at diagnosis; among these patients, 23 patients in the VRE-colonized group (50%) had a B-cell malignancy (lymphoma, myeloma, or chronic lymphocytic leukemia). CONCLUSION: Besides already anticipated diseases like leukemia, B-cell malignancies are also at high risk for colonization. This proclivity may be attributed to lack of gastrointestinal IgA due to hypogammaglobulinemia. Prolonged hospitalization (>7 days) may also be accepted as a risk factor, independent of diagnosis or antibiotic use. Performance status is also an important factor for colonization, which may be related to poorer hygiene and increased external help.