Germline genetic variants in Turkish familial multiple myeloma/monoclonal gammopathy of undetermined significance cases.

Multiple myeloma (MM) is a haematological malignancy primarily affecting the elderly, with a striking male predilection and ethnic disparities in incidence. Familial predisposition to MM has long been recognized, but the genetic underpinnings remain elusive. This study aimed to investigate germline variants in Turkish families with recurrent MM cases. A total of 37 MM-affected families, comprising 77 individuals, were included. Targeted next-generation sequencing analysis yielded no previously reported rare variants. Whole exome sequencing analysis in 11 families identified rare disease-causing variants in various genes, some previously linked to familial MM and others not previously associated. Notably, genes involved in ubiquitination, V(D)J recombination and the PI3K/AKT/mTOR pathway were among those identified. Furthermore, a specific variant in BNIP1 (rs28199) was found in 13 patients across nine families, indicating its potential significance in MM pathogenesis. While this study sheds light on genetic variations in familial MM in Turkey, its limitations include sample size and the absence of in vivo investigations. In conclusion, familial MM likely involves a polygenic inheritance pattern with rare, disease-causing variants in various genes, emphasizing the need for international collaborative efforts to unravel the intricate genetic basis of MM and develop targeted therapies.

Bortezomib-based therapy for relapsed/refractory multiple myeloma in real-world medical practice.

OBJECTIVE: The efficacy and safety of bortezomib-based therapy for relapsed/refractory multiple myeloma (RRMM) in clinical trials may differ from the oncology practice experience. The electronic VELCADE® OBservational Study was designed to prospectively evaluate bortezomib for multiple myeloma (MM) in real-world medical practice. METHOD: Patients scheduled to receive intravenous bortezomib for MM were eligible. The primary objective was to evaluate clinical outcomes, including response, time to response, time to next therapy, treatment-free interval, progression-free survival (PFS), and overall survival (OS). Secondary objectives included safety and healthcare resource utilization. RESULTS: In total, 873 patients with a median of two therapy lines prior to initiating bortezomib were included. The overall response rate (≥partial response) was 69%, including 37% complete response/near-complete response. Median time to response was 1.8 months, median time to next therapy was 9.7 months, and median treatment-free interval was 7.9 months. After 22.6 months' median follow-up, median PFS was 12.0 months and median OS was 36.1 months. The most common adverse events (AEs) were neuropathy not otherwise specified (19%), diarrhea NOS, and thrombocytopenia (each 17%); 230 (26%) patients discontinued bortezomib due to AEs. Of 689 (79%) patients without baseline peripheral neuropathy (PN), the rate of new-onset any-grade PN increased to 51% (12% grade 3/4) by cycle 8. Overall, 244 (28%) patients were hospitalized, 372 (43%) attended an outpatient visit, and 341 (39%) underwent a diagnostic/therapeutic procedure during bortezomib treatment. CONCLUSION: These prospective real-world data demonstrate the effectiveness and safety of bortezomib-based therapy for RRMM and confirm high response rates and long OS for this population.

Preliminary Report of the Academic CAR-T (ISIKOK-19) Cell Clinical Trial in Turkey: Characterization of Product and Outcomes of Clinical Application

Objective: Chimeric antigen receptor T (CAR-T) cell therapies have already made an impact on the treatment of B-cell malignancies. Although CAR-T cell therapies are promising, there are concerns about commercial products regarding their affordability and sustainability. In this preliminary study, the results of the first production and clinical data of an academic CAR-T cell (ISIKOK-19) trial in Turkey are presented. Materials and Methods: A pilot clinical trial (NCT04206943) designed to assess the safety and feasibility of ISIKOK-19 T-cell therapy for patients with relapsed and refractory CD19+ tumors was conducted and participating patients received ISIKOK-19 infusions between October 2019 and July 2021. The production data of the first 8 patients and the clinical outcome of 7 patients who received ISIKOK-19 cell infusions are presented in this study. Results: Nine patients were enrolled in the trial [5 with acute lymphoblastic leukemia (ALL) and 4 with non-Hodgkin lymphoma (NHL)], but only 7 patients could receive treatment. Two of the 3 participating ALL patients and 3 of the 4 NHL patients had complete/partial response (overall response rate: 72%). Four patients (57%) had CAR-T-related toxicities (cytokine release syndrome, CAR-T-related encephalopathy syndrome, and pancytopenia). Two patients were unresponsive and had progressive disease following CAR-T therapy. Two patients with partial response had progressive disease during follow-up. Conclusion: Production efficacy and fulfillment of the criteria of quality control were satisfactory for academic production. Response rates and toxicity profiles were also acceptable for this heavily pretreated/refractory patient group. ISIKOK-19 cells appear to be a safe, economical, and efficient treatment option for CD19+ tumors. However, the findings of this study need to be supported by the currently ongoing ISIKOK-19 clinical trial.

The predictive value of stimulation index calculated by modified mixed lymphocyte culture in the detection of GVHD following hematopoietic stem cell transplantation.

OBJECTIVE: Mixed lymphocyte culture (MLC) is one of the routine tests performed prior to hematopoietic stem cell transplantation (HSCT) as a predictive assay for assessing the quality of donor matching and graft-versus-host disease (GVHD). The stimulation index is one of the formulas of the MLC test, and it is used for evaluation of matching between donor and recipient. Modified MLC (mMLC) test is produced by adding various cytokines to the MLC test, and increased sensitivity has been reported with this modification. METHODS: The importance of the stimulation index values in MLC and mMLC tests was evaluated in 59 patients who received HSCs from human leukocyte antigen-identical sibling donors. In the mMLC test, cytokines were added as interleukin (IL)-2, IL-2 + IL-4 and IL-2 + interferon (IFN)-gamma + tumor necrosis factor (TNF)-alpha. Stimulation index values in mMLC test were compared with stimulation index values in MLC test. RESULTS: Twenty-three (39%) patients developed GVHD. When evaluated in terms of stimulation index >1 patients, in MLC, 55% of the patients developed GVHD (p=0.229), whereas these values were 75% in the IL-2 added mMLC test (p=0.035), 100% in the IL-2 + IL-4 added mMLC test (p=0.076) and 85.7% in the IL-2 + IFN-gamma + TNF-alpha added mMLC test (p=0.015). CONCLUSION: mMLC increased the sensitivity of the test. The relation between the positive results and evidence of GVHD after transplantation was found significant.

Hyperbaric Oxygen: an important treatment modality in severe hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation.

OBJECTIVE: Hemorrhagic cystitis (HC) is a generally self-limited complication of hematopoietic stem cell transplantation (HSCT). It may occur in the early or late posttransplant period and can promote sometimes severe morbidity. We analyzed our data regarding HC in allogeneic HSCT patients in order to establish the efficacy of hyperbaric oxygen (HBO) therapy in severe HC and to document the main problems during its use. METHODS: Between March 1993 and August 2006, 161 patients received allogeneic HSCT. Mesna, hyperhydration and forced diuresis were used as early HC prophylaxis of cyclophosphamide-induced HC. However, HC was diagnosed in 49 of the 161 recipients and 17 of them were considered as severe HC. We analyzed their data retrospectively. RESULTS: Forced diuresis with hyperhydration (up to 8 L/day) and transfusion support to maintain a platelet count above 30x109/L were sufficient in 10 of the 17 patients with severe HC. Alternative therapies used included intravesical irrigation with formalin and prostaglandin (PG)F2 alpha and HBO, and HBO appeared to be the most useful among them. CONCLUSION: We conclude that HBO offers a noninvasive therapeutic alternative in the management of intractable HC in the HSCT setting.

Bortezomib retreatment for relapsed and refractory multiple myeloma in real-world clinical practice.

AIMS: Studies have shown that bortezomib retreatment is effective in relapsed/refractory multiple myeloma (MM). The observational, prospective electronic VELCADE® OBservational Study (eVOBS) study assessed bortezomib-based therapies for patients with MM in everyday practice. Here, we report on those patients receiving retreatment with bortezomib. METHODS: Consenting adults scheduled to receive bortezomib for MM were enrolled at 162 sites across Europe, Canada, Brazil, Russia, and Turkey between 2006 and 2010. Retrospective data on prior therapies and prospective observational data after bortezomib initiation were captured electronically at baseline, after every bortezomib cycle, and every 12 weeks after discontinuation or progression. Investigator-assessed responses and adverse events (AEs) were evaluated. RESULTS: Ninety-six of 873 patients enrolled to eVOBS received bortezomib as first retreatment for progressive disease during the prospective observation period. Median age was 62 years, 53% were male, and median number of prior therapies at retreatment was 4. Overall, 41% of patients initiated bortezomib retreatment in combination with dexamethasone, 16% in combination with lenalidomide, and 21% received monotherapy. Rate of partial response or better (≥PR) was 75% at initial bortezomib therapy, including 44% complete response (CR)/near CR (nCR); at retreatment, ≥PR rate was 46%, including 15% CR/nCR. Median progression-free survival was 11.4 months (95% confidence interval [CI]: 9.1-12.7) from start of initial bortezomib treatment and 6.4 months (95% CI: 4.4-7.2) from start of retreatment. Median overall survival from start of retreatment was 17.6 months (95% CI: 14.4-23.5). Of the 96 patients retreated with bortezomib, 77% reported an AE. Peripheral neuropathy during bortezomib retreatment occurred in 49% of patients, including 10% grade 3/4. CONCLUSION: These data suggest that retreatment with bortezomib is a feasible option for patients with relapsed/refractory MM.

Intracoronary autologous bone marrow-derived mononuclear cell transplantation improves coronary collateral vessel formation and recruitment capacity in patients with ischemic cardiomyopathy: a combined hemodynamic and scintigraphic approach.

This study investigated the effects of intracoronary autologous bone marrow-derived mononuclear cell (BMC) transplantation on coronary microcirculation. Fifteen patients with ischemic cardiomyopathy were treated by intracoronary infusion of BMCs via the patent infarct-related artery. The thermodilution-derived coronary flow reserve, index of microvascular resistance, pressure-derived collateral flow index, and coronary wedge pressure were measured at baseline and at 6 months. Successive balloon inflations during BMC transplantation were performed to observe the recruitment in pressure-derived collateral flow index and coronary wedge pressure, and the percentage changes between baseline and 6 months were calculated. The mean (SD) coronary flow reserve increased from 1.3 (0.4) to 2.1 (0.5), and the mean (SD) index of microvascular resistance decreased from 44.9 (24.4) to 21.2 (14.1) (P = .001 for both). The mean (SD) improvement in pressure-derived collateral flow index (from 0.14 [0.05] to 0.22 [0.08]) was also statistically significant (P = .001). Similarly, the percentage improvements in pressure-derived collateral flow index and coronary wedge pressure were statistically significant (P = .01 for both). The percentage improvement in perfusion assessed by single-photon emission computed tomography strongly correlated with the percentage changes in pressure-derived collateral flow index (r = 0.88, P = .001) and coronary wedge pressure (r = 0.69, P = .01). These results demonstrate for the first time (to our knowledge) that intracoronary autologous BMC transplantation improves coronary collateral vessel formation and recruitment capacity in human subjects.

[Nosocomial respiratory syncytial virus infections in three cases in a bone marrow transplantation unit]. / Kemik iligi nakli ünitesinde yatan üç olguda nozokomiyal solunum sinsityal virus enfeksiyonu.

Here we report the spread of respiratory syncytial virus (RSV) infection among three patients, who were hospitalized in an adult hematopoetic stem cell transplantation (HSCT) unit because of hematologic diseases, and effects of RSV infection on post-transplant outcome. The patients were placed into reverse isolation for administration of preparative regimens (high dose chemotherapy) in HSCT unit with high-energy particulate air (HEPA)-filtered single rooms. First case was a 62 years-old man with advanced multiple myeloma, which was refractory to multiple line treatment with high dose steroid including regimens and with secondary acute myelogenous leukaemia (AML); second case was a 45 years-old male patient with multiple myeloma, who had undergone autologous HSCT following high dose chemotherapy; third case was a 52 years-old man with AML that was refractory to multiple line treatment and had undergone allogeneic HSCT from a HLA-matched unrelated donor. Nasopharyngeal aspirate samples were collected from the patients in order to search for RSV positivity. RSV was investigated by in-house nested polymerase chain reaction (PCR) in the first patient and by direct antigen detection method (Monofluoscreen RSV-Biorad, France) in the others. First case had clinical picture of RSV infection just on the HSCT day when high dose chemotherapy has already been given. As RSV-RNA analysis yielded positive result, peroral ribavirin was initiated. Engraftment did not occur in this patient. He developed severe respiratory failure which necessitated mechanical ventilatory support, however, he has succumbed. After the detection of RSV positive index case, weekly screening of RSV in other five patients in the same unit had been performed. Following the first case, after nine and 17 days, respectively, RSV positivity was detected in two more patients. While clinical signs and symptoms of RSV infection developed in second case, third case remained asymptomatic. Both of the following patients had received ribavirin very early at first RSV positivity and recovered from RSV infection. Engraftment did not occur in the last patient who had undergone allogeneic HSCT from a HLA-matched unrelated donor and a second HSCT was performed. As a result, in HSCT patients, early diagnosis of RSV infection by PCR analysis may provide support to postpone immunosupressive treatment and help assesment of the management.

Autologous stem cells collected after debulking by high dose chemotherapy in late phase chronic myeloid leukemia may improve Imatinib efficacy.

The current curative therapeutic option for the treatment of chronic myeloid leukemia (CML) in the chronic phase is still allogeneic stem cell transplantation (SCT). For the patients who are not candidates for allogeneic SCT, Imatinib is the treatment of choice. It was found that high dose chemotherapy with autologous stem cell rescue prolongs the disease-free survival and may also restore sensitivity to interferon. Here we report the results of Imatinib treatment in three late-phase CML patients who were submitted to autologous SCT following resistance to interferon. Complete cytogenetic response and major molecular response were achieved in the three cases. Imatinib has the potential to induce late molecular remissions during the course of treatment and its effect may be optimized by a previous autologous SCT in this type of patients.

Allogeneic Hematopoietic Stem Cell Transplantation for Adult Acute Lymphoblastic Leukemia: Results from a Single Center, 1993-2011.

Background: For adult ALL patients, the indications and appropriate timing of allogeneic hematopoietic stem cell transplantation (AHSCT) continue to be debated. The primary aim of this single-institution study was to compare the results of our adult ALL patients that had been allografted with those reported in the current literature. Subjects and Methods: This study included 53 consecutive adults with acute lymphoblastic leukemia (ALL) who underwent allogeneic hematopoietic stem cell transplantation (AHSCT) with myeloablative (92%) and reduced-intensity (8%) conditioning between 1993 and 2011. Results: Mean patient age was 27 years (SD:8.62) and donor age was 33.7 years (SD:9.47). Fourteen patients were in first remission; 21 in ≥2nd remission, 15 in relapse and 3 had primary refractory leukemia. Thirty-four, 15 and 4 patients received busulfan plus cyclophosphamide, cyclophosphamide/total body irradiation and fludarabine-based regimens, respectively. For graft-versus-host disease (GVHD) prophylaxis, cyclosporine plus methotrexate were used. Forty-six donors were related and 7 were unrelated. Thirty patients received granulocyte-colony stimulating factor (G-CSF) mobilized peripheral blood and 23 received bone marrow as stem cell source. Twenty-six patients relapsed at a mean duration of 11.3 months (SD:19.1). Forty-four patients succumbed to their disease after a mean follow-up of 13.6 months (SD:19.5). The cause of mortality was relapse (n=24; 54.5%) and transplant-related etiologies (n=20; 45.5%). The estimated five year probabilities of overall survival (OS) and progression-free survival (PFS) were 37% and 12%, respectively. Conclusion: By multivariate analyses, transplantation in first remission was the most important predictor of transplant success.

Complete Remission of Burkitt Lymphoma After Surgical Excision: A Case Report.

Burkitt lymphoma (BL) is a highly aggressive B cell non-Hodgkin lymphoma that has a high proliferation rate. The prognosis for BL is generally favorable, with cure rate of 75-90 % with modern chemoimmunotherapy regimens. Prompt administration of multiagent immunochemotherapy regimens is critical, because BL is almost always fatal if left untreated. Nevertheless here we report a case of BL that is still in complete remission after more than 4 years without any further treatment after surgical excision of the involved lymph node.

Isolated extramedullary cutaneous relapse despite concomitant severe graft-vs.-host disease and tissue chimerism analysis in a patient with acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation: A case report.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment option for patients with acute lymphoblastic leukemia (ALL). The curative potential of allo-HSCT for ALL is, in part, due to the graft-vs.-leukemia (GVL) effect, in addition to the intensive conditioning chemo-radiotherapy. However, relapse remains the major cause of treatment failure following allo-HSCT for ALL. In the allo-HSCT setting, testing for genetic markers of hematopoietic chimerism has become a part of the routine diagnostic program. Routine chimerism analysis is usually performed in peripheral blood or bone marrow; in fact, little is known about the value of tissue chimerism in patients with extramedullary relapse (EMR) after the allo-HSCT setting. The present study reports on, a case of a patient with ALL who experienced isolated cutaneous EMR despite ongoing graft-vs.-host disease (GVHD), and the results of peripheral blood and skin tissue chimerism studies using multiplex polymerase chain reaction (PCR) of short tandem repeats (STR-PCR). The present case demonstrates that, although complete remission and/or chimerism may be achieved in the bone marrow, chimerism achieved at the tissue level, and the subsequent GVL effect, may be limited, despite concomitant severe GVHD following allo-HSCT. Our tissue chimerism analysis results provide a good example of how skin tissue may be a 'sanctuary' site for effector cells of GVL, despite active GVHD and complete hematopoetic chimerism.

Allogeneic stem cell transplantation in a blast-phase chronic myeloid leukemia patient with carbapenem-resistant Klebsiella pneumoniae tricuspid valve endocarditis: A case report.

In chronic myeloid leukemia (CML), the occurrence of blastic transformation is rare. Treatment outcome is generally poor. Allogeneic stem cell transplantation (allo-SCT) is the only potentially curative treatment option for advanced-phase CML. Infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates are associated with high morbidity and mortality rates, particularly in patients with haematological malignancies. Infection and colonization by these multiresistant bacteria may represent a challenge in SCT recipients for the management of post-transplantation complications, as well as for the eligibility to receive a transplant in patients who acquire the pathogen prior to the procedure. We herein report the case of a blast-phase CML patient with a highly resistant, CRKP-associated tricuspid valve endocarditis, who was treated with a combination of systemic antimicrobial therapy and surgical valve repair, and subsequently underwent a successful allo-SCT.

The Clinical Significance of IDH Mutations in Essential Thrombocythemia and Primary Myelofibrosis.

BACKGROUND: Limited data exist regarding impact of IDH mutations in Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs). Prognostic significance of IDH mutations was asessed in 184 Ph-negative MPN patients - 107 essential thrombocythemia (ET) and 77 primary myelofibrosis (PMF). METHODS: High-resolution melting (HRM) analysis was used to detect IDH1 and IDH2 mutations. RESULTS: PMF and ET patients showed no significant difference for prevalence of IDH mutations. Mutant IDH (IDH1 or IDH2) was documented in five of PMF (6.5%) and two of ET patients (1.9%). IDH mutations in ET patients included one IDH1 R132C and one IDH2 R140Q. Of the five IDH-mutated PMF patients, four (80%) displayed IDH1 (three IDH1 R132C and one IDH1 R132S) and one (20%) carried IDH2 (IDH2 R140Q) mutation. Sixty percent (three in five) of IDH-mutated PMF patients carried JAK2V617F with following allele burdens: 31-50%, 5-12.5% and 31-50%, respectively. Three of 77 PMF patients (3.9%) simultaneously harbored IDH and JAK2V617F mutations. IDH mutations in PMF showed a trend towards higher rate in females (100% and 52.8%, respectively). Bleeding complications were significantly higher in IDH-mutated PMF patients compared to IDH wild-type counterparts. Trend towards a lower prevalance of acetylsalicylic acid (ASA) use was present in IDH mutant PMF patients compared to wild-type counterparts (20% and 63.9%, respectively). Death rate was higher in IDH-mutated PMF patients compared to IDH wild-type PMF patients (60% and 15.3%). In univariate analysis, a significantly shorter leukemia-free survival (LFS) was observed in IDH-mutated PMF patients. CONCLUSIONS: We conclude that IDH mutations indicate a risk for leukemic transformation in PMF.

Complete resolution of transplantation-associated thrombotic microangiopathy and hepatic veno-occlusive disease by defibrotide and plasma exchange.

Transplantation-associated thrombotic microangiopathy has been associated with significantly reduced survival following allogeneic bone marrow transplantation. We describe here the course of Transplantation-associated thrombotic microangiopathy and hepatic veno-occlusive disease, and response to plasma exchange therapy. A 19-year-old male patient underwent hematopoietic stem cell transplantation (HSCT) from his HLA-matched brother for lymphoblastic lymphoma in the first complete remission. Transplantation-associated thrombotic microangiopathy was diagnosed 17 days after transplantation. At that time, neurological abnormalities were not present. Cyclosporin A (CsA) was discontinued. Hematological stabilization was recorded. On day +20, abdominal distention, painful hepatomegaly and ascites complicated the clinical picture. With a high hepatic venous pressure gradient (18mmH20), veno-occlusive disease of the liver was diagnosed and defibrotide was started, which resulted in a dramatic cessation of pain and increase in urinary output. However, transplantation-associated thrombotic microangiopathy-related symptoms progressed and plasma exchange was instituted, which resulted in worsening of veno-occlusive disease symptoms. He was referred to the Intensive Care Unit due to respiratory compromise and was intubated. Plasma exchange was continued in order after hemofiltration. In three days, fever resolved, hemofiltration could be stopped, and ventilator dependence ended. After 19 aphereses, serum LDH level returned to normal and schistocytes were minimal on microscopic examination of the blood film. Platelet count increase was more gradual. Plasma exchange was discontinued. On the 40th day of defibrotide, all symptoms related with veno-occlusive disease were resolved and defibrotide was stopped. We think that our case is important to establish the relation and management strategy of these two small vessel complications of HSCT.

Prognostic significance of ASXL1, JAK2V617F mutations and JAK2V617F allele burden in Philadelphia-negative myeloproliferative neoplasms.

BACKGROUND: Despite insights into the genetic basis of Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs), a significant proportion of essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients present with no known MPN disease alleles. There were no previous studies investigating the impact of ASXL1 mutations in Ph-negative MPNs in Turkey. In the current study, we investigated the prognostic significance of ASXL1 mutations in Turkish MPN patients. We also aimed to determine the prognostic significance of JAK2V617F allele burden and the relationship of JAK2V617F mutation with ASXL1 mutations in Ph-negative MPNs. METHODS: About 184 patients from a single center diagnosed with Ph-negative MPNs were screened for ASXL1, JAK2V617F mutations, and JAK2V617F allele burden: 107 ET and 77 PMF. RESULTS: A total of 29 ASXL1 mutations were detected in 24.7% of PMF and 8.4% of ET patients. ASXL1-mutated ET patients showed a trend toward an increase in the incidence of cerebrovascular events and higher total leukocyte counts. ASXL1-mutation in PMF was associated with older age and a higher prevalence of bleeding complications. In univariate analysis, overall survival (OS) was significantly reduced in ASXL1-mutated PMF patients. In multivariate analysis, Dynamic International Prognostic Scoring System-plus high-risk category and ASXL1 mutation status were independently associated with shorter survival in PMF. In PMF, mutational status and allele burden of JAK2V617F showed no difference in terms of OS and leukemia-free survival. CONCLUSION: We conclude that ASXL1 mutations are molecular predictors of short OS in PMF.

The Burden of JAK2V617F Mutated Allele in Turkish Patients With Myeloproliferative Neoplasms.

BACKGROUND: Studies regarding the impact of JAK2V617F allele burden on phenotypic properties and clinical course in Philadelphia-negative myeloproliferative neoplasms (Ph-negative MPNs) have reported variable results. We aimed to analyze the association of mutated JAK2V617F allele burden with laboratory characteristics and clinical phenotype in Turkish patients (107 essential thrombocythemia (ET) and 77 primary myelofibrosis (PMF)). METHODS: Peripheral blood samples of 184 patients with Ph-negative MPNs were analyzed for JAK2V617F allele status and burden. JAK2 MutaScreen assay (Ipsogen, Luminy Biotech, Marseille, France) was used to detect the JAK2V617F status and quantitative JAK2V617F allele burdens in genomic DNA using TaqMan allelic discrimination. RESULTS: Frequency of JAK2V617F-positive patients with high mutation load (allele burden > 50%) was higher in PMF compared to ET (23.4% and 4.7%, respectively; P = 0.001). We found significant association between ET patients with high JAK2V617F allele burden and lower hemoglobin (Hgb) and hematocrit (Hct), higher LDH levels and more prevalent massive splenomegaly (P = 0.001, P = 0.001, P = 0.012 and P = 0.015, respectively). ET patients with high mutation load displayed higher prevalence of bleeding compared to low mutation load and wild-type mutational status (P = 0.003). Rate of DVT was significantly higher in ET patients with mutant allele burden in upper half compared to lower half and wild-type (P = 0.029). We observed significant association between PMF patients with high JAK2V617F allele burden and higher Hgb, Hct levels and leukocyte counts (P = 0.003, P = 0.021 and P = 0.001, respectively). CONCLUSIONS: Our study demonstrated JAK2V617F allele burden correlates with clinical features in ET and PMF. We conclude quantification of JAK2V617F mutation contributes to the workup of Ph-negative MPNs.

Cyclosporine-associated hyperkalemia: report of four allogeneic blood stem-cell transplant cases.

BACKGROUND: Nephrotoxicity is a well-known effect of cyclosporine (CsA) that causes a reduction in glomerular filtration rate through vasoconstriction of the afferent glomerular arterioles and may result in acute renal failure. Isolated CsA-induced hyperkalemia occurring through different mechanisms is also common. However, there are only a few "case reports" addressing this phenomenon in allogeneic bone marrow transplantation patients. In this report, we propose mechanisms and methods of managing CsA-associated hyperkalemia in allogeneic transplantation. METHODS: We report on four allogeneic blood stem- cell transplant cases and a review of the literature. RESULTS: Four adult leukemia patients underwent allogeneic peripheral blood stem cell transplantation and received CsA as a part of their graft-versus-host disease prophylaxis. The patients developed hyperkalemia, despite adequate kidney function. CsA seemed to be the only pharmaceutical agent to which this electrolyte abnormality could be attributed. Renal tubule dysfunction and secondary hypoaldosteronism seemed to be the reasons for CsA-associated hyperkalemia. CONCLUSION: This report of four cases demonstrates that CsA should be considered among the possible causes of hyperkalemia in bone marrow transplantation. There may be a need for urgent intervention depending on the severity of hyperkalemia. Monitoring of blood CsA level and dose adjustment are important for the prevention of this complication.

A male-specific increase in the HLA-DRB4 (DR53) frequency in high-risk and relapsed childhood ALL.

Previous studies reported significant HLA-DR associations with various leukemias one of which is with HLA-DRB4 (DR53) family in male patients with childhood ALL. We have HLA-DR-typed 212 high-risk or relapsed patients with childhood (n=114) and adult (n=98) ALL and a total of 250 healthy controls (118 children, 132 adult) by PCR-SSP analysis. The members of the HLA-DRB3 (DR52) family were underrepresented in patients most significantly for HLA-DRB1*12 (P=0.0007) and HLA-DRB1*13 (P=0.0001). In childhood ALL, the protective effect of DRB3 was evident in homozygous form (P=0.001). The DRB4 marker frequency was increased in males with childhood ALL (67.4%) compared to age- and sex-matched controls (42.1%, P=0.003) and female patients (35.7%, P=0.004). Besides being a general marker for increased susceptibility to childhood ALL in males, HLA-DRB4 is over-represented in high-risk patients. These results further suggest that the HLA system is one of the components of genetic susceptibility to leukemia but mainly in childhood and in boys only.

Diffuse alveolar hemorrhage associated with thrombotic thrombocytopenic purpura after allogeneic bone marrow transplantation.

Alveolar hemorrhage is an early complication after bone marrow transplantation (BMT) and often associated with inflammatory pulmonary processes. We present a case of diffuse alveolar hemorrhage associated with BMT associated thrombotic thrombocytopenic purpura (BMT-TTP). An 18-years-old man with acute myeloid leukaemia (FAB; M5) underwent ABO incompatible BMT from his HLA-identical sister. On the 37th day of BMT, BMT-TTP was diagnosed with the occurrence of red cell fragmentation and rise in serum lactic dehydrogenase (LDH) level with severe sudden decrease in hemoglobin and platelet levels. Cyclosporine A (CsA) was ceased and plasma infusion with plasma exchange was started. On the 42nd day of BMT, the diagnosis of diffuse alveolar hemorrhage was made by the clinical, bronchoscopic and bronchoalveolar lavage fluid findings. Alveolar hemorrhage among patients with BMT-TTP has been scarce reported. These two complications may be regarded as related, as small vessel injury is a central feature in both and they may share aetiological and pathogenetic factors.