High burden of clonal mast cell disorders and hereditary α-tryptasemia in patients who need Hymenoptera venom immunotherapy.

BACKGROUND: In patients who require venom immunotherapy (VIT), there is a need to identify underlying mast cell (MC) disorders since these may affect the risk and severity of future sting reactions and the long-term effectiveness of VIT. METHODS: 1319 individuals with Hymenoptera venom allergy (HVA) who needed VIT from referral centers in Slovenia, Austria, Croatia, and Poland underwent examination for KIT p.D816V in peripheral blood leukocytes (PBL) using a highly sensitive PCR test and tryptase genotyping by digital droplet PCR. We also included 183 control individuals with large local reactions (LLRs) to Hymenoptera stings and with asymptomatic sensitization to Hymenoptera venoms. RESULTS: 285 of 1319 individuals recommended for VIT (21.6%) were positive for KIT p.D816V in PBL, preferably those who present with severe reaction (33.9% [n = 207 of 610] with Ring-Messmer grade 3-4 vs. 11% [n = 78 of 709] with Grade 1-2; p < .0001), whereas only 1.3% (n = 2 of 152) of controls with LLR and none with asymptomatic sensitization (n = 31) had KIT p.D816V. KIT p.D816V allelic burden was higher in those with severe reaction (median 0.018% [n = 207] in Grade 3-4 vs. 0.001% [n = 78] in Grade 1-2; p < .0001), and the majority had normal baseline serum tryptase levels (69% [n = 196 of 285]). All KIT p.D816V-positive individuals (n = 41) who underwent bone marrow (BM) biopsy were found to have underlying clonal diseases, principally BM mastocytosis. HαT was also associated with severe HVA and symptoms (p < .01), and remarkably, 31.0% (n = 31 of 100) were found to have concomitant KIT p.D816V. Concomitant HαT and KIT p.D816V showed an additive effect, and having both was associated with the highest risk for severe HVA, even higher than having either HαT or KIT p.D816V alone (OR = 3.8; p < .01). CONCLUSIONS: By employing prospective universal tryptase genotyping and examination for KIT p.D816V in PBL in large HVA populations, we have demonstrated a high burden of clonal MC disorders and HαT in patients who require VIT.

Routine KIT p.D816V screening identifies clonal mast cell disease in patients with Hymenoptera allergy regularly missed using baseline tryptase levels alone.

BACKGROUND: Clonal mast cell disorders and elevated basal serum tryptase (BST) levels with unknown cause(s) are associated with severe Hymenoptera venom-triggered anaphylaxis (HVA). However, some individuals with clonal disease have a normal BST level (<11.4 ng/mL). OBJECTIVE: Our aim was to evaluate whether screening for KIT p.D816V in the blood is a useful clinical tool to risk-stratify patients with venom allergy. METHODS: We prospectively recruited 374 patients with Hymenoptera allergy and no overt signs of mastocytosis who were referred to our center during the years 2018 and 2019. KIT p.D816V was determined in their peripheral blood by quantitative PCR, and tryptase genotyping was performed by droplet digital PCR. RESULTS: In all, 351 patients (93.9%) had normal levels of BST, and KIT p.D816V was detected in 8% of patients (28 of 351), predominantly in patients with the most severe Mueller grade IV anaphylaxis (18.2% [24 of 132] vs 1.8% in patients with lower grades [4 of 88 with grade III and 0 of 131 with other grades]; P < .001). In grade IV patients with a normal BST level, KIT p.D816V was associated with more severe symptoms, including a significantly higher frequency of loss of consciousness (58.3% [14 of 24] vs 34.3% [37 of 108]; P = .03) and absence of skin symptoms (41.7% [10 of 24] vs 15.7% [17 of 108]; P = .004). Among patients with a normal BST level, KIT p.D816V (OR = 10.25 [95% CI = 3.75-36.14]; P < .0001) was the major risk factor associated with severe HVA. Hereditary α-tryptasemia (HαT) due to increased germline copies of TPSAB1 encoding α-tryptase was the most common cause (65.2% [15 of 23]) of elevated BST level in patients with HVA, and together with KIT p.D816V, it accounted for 90% of BST level elevations (20 of 23) in patients with HVA. CONCLUSION: These results indicate that routine KIT p.D816V screening identifies clonal disease in high-risk patients with HVA who are regularly missed when BST level is used alone.

Complement activation and cryoglobulinemia are common in monoclonal gammopathy of renal significance: Data from a case series.

INTRODUCTION: Monoclonal gammopathy of renal significance (MGRS) denotes kidney diseases caused by monoclonal immunoglobulins in patients who do not have an overt hematological malignancy. Treatment is primarily directed against the underlying clone. Complement activation and cryoglobulinemia are known factors that can contribute to tissue damage, however, the full extent of their involvement is not clear. MATERIALS AND METHODS: This was a retrospective study including all patients with MGRS referred for consultation to our hospital over a 3-year period. RESULTS: We identified 17 patients, of which 12 had proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID). Treatment with anti-clonal or immunosuppressive therapy was successful in 60% of patients with PGNMID, and treatment success was more common in patients with λ chain (100%) compared to κ chain deposits (20%). Serum markers of complement involvement were identified in 41% of all patients (88% of tested samples), most commonly high serum C5b-9 values or anti-factor H autoantibodies (both 24%). Patients with complement involvement did not respond well to treatment, which was unsuccessful in all treated patients with anti-factor H autoantibodies and 75% of patients with high serum C5b-9 values. Cryoglobulinemia was identified in 29% of all patients (71% tested samples) and was monoclonal in 40% of positive cases and mixed in 60%. None of the patients with cryoglobulinemia had organized deposits, however, there was a trend toward more common intramembranous deposits. In patients with monoclonal cryoglobulinemia both anti-clonal and immunosuppressive treatment were unsuccessful. All patients with mixed cryoglobulinemia were treated successfully with immunosuppressive therapy. CONCLUSION: Treatment of patients with PGNMID was successful in most cases. Complement involvement as well as monoclonal and mixed cryoglobulinemia were relatively common in our cohort, with the first two generally associated with unsuccessful treatment and the latter with successful treatment.

Treatment of ChAdOx1 nCoV-19 Vaccine-Induced Immune Thrombotic Thrombocytopenia Related Acute Ischemic Stroke.

Recently cases of vaccine-induced immune thrombotic thrombocytopenia (VITT) and thrombosis following the adenoviral vector vaccine against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were reported. A mechanism similar to heparin-induced thrombocytopenia was proposed with antibodies to platelet factor 4 (PF4). Vaccine related arterial thrombosis in the brain is rare but life-threatening and optimal treatment is not established. We report clinical, laboratory, imaging findings and treatment in a 51-year-old female presenting with acute left middle cerebral artery (MCA) occlusion 7 days after the first dose of ChAdOx1 nCoV-19 vaccine. Due to low platelet count and suspicion of VITT she was not eligible for intravenous thrombolysis (IVT) and proceeded to mechanical thrombectomy (MER) with successful recanalization four hours after onset of symptoms. Treatment with intravenous immunoglobulin (IVIG) and heparin pentasaccharide fondaparinux was initiated. Presence of anti-PF4 antibodies was confirmed. The patient improved clinically with normalization of platelet count. Clinicians should be alert of VITT in patients with acute ischemic stroke after ChAdOx1 nCov-19 vaccination and low platelet counts. MER showed to be feasible and effective. We propose considering MER in patients with VITT and large vessel occlusion despite thrombocytopenia. High-dose IVIG should be started immediately. Alternative anticoagulation to heparin should be started 24 hours after stroke onset unless significant hemorrhagic transformation occurred. Platelet transfusion is contraindicated and should be considered only in severe hemorrhagic complications. Restenosis or reocclusion of the revascularized artery is possible due to the hypercoagulable state in VITT and angiographic surveillance after the procedure is reasonable.

Feasibility and safety of exercise training and nutritional support prior to haematopoietic stem cell transplantation in patients with haematologic malignancies.

BACKGROUND: Prehabilitation with regular exercise and nutritional care for patients undergoing surgeries for malignant disease was recently introduced to increase physiologic reserve prior to the procedure, accelerate recovery and improve outcomes. This study aimed to investigate the feasibility and safety of combined exercise training and nutritional support in patients with haematologic malignancies prior to haematopoietic stem cell transplantation (HSCT). METHODS: In this single-arm pilot study, 34 HSCT candidates were enrolled at least two weeks before admission for the procedure. Patients performed aerobic exercises at least 4 days per week for 20-30 min and strength exercises 3 days per week for 10-20 min. They received daily supplements of whey protein (0.3-0.4 g/kg body weight) and oral nutritional supplements if needed. The primary endpoints were feasibility (acceptability > 75%, attrition < 20%, adherence > 66%) and safety. The secondary endpoints were fat-free mass (FFM), muscle strength, physical performance and health-related quality of life (HRQoL) at HSCT. RESULTS: The rate of acceptability, attrition and adherence to aerobic exercise, strength exercise and protein supplement consumption was 82.4, 17.8, 71, 78 and 80%, respectively. No severe adverse events were reported. Twenty-eight patients participated in the study for a median of 6.0 weeks (range, 2-14). They performed aerobic exercises 4.5 days per week for 132 min per week and strength exercises 3.0 times per week. Patients consumed 20.7 g of extra protein daily. At the end of the programme, we recorded increases of 1.1 kg in FFM (p = 0.011), 50 m in walking distance in the 6-min walking test (6MWT) (p < 0.001), 3.3 repetitions in the 30-s chair-stand test (30sCST) score (p < 0.001) and 2.6 kg in handgrip strength (p = 0.006). The EORTC QLQ-C30 scores improved by 8.6 (p < 0.006) for global health status, 8.3 (p = 0.009) for emotional functioning, and 12.1 (p = 0.014) for social functioning. There was less fatigue, nausea and insomnia (p < 0.05). CONCLUSIONS: Our study shows that a multimodal intervention programme with partially supervised exercise training combined with nutritional support prior to HSCT is feasible and safe. Patients showed improvements in FFM, physical performance and HRQoL. Additional research is needed to assess the possible positive effects of such interventions.

Improved survival of AML patients by addition of cladribine to standard induction chemotherapy.

One hundred and eight consecutive acute myeloid leukemia (AML) patients aged 60 or less treated with two different induction regimens were retrospectively analyzed. Induction regimen for the first 50 consecutive patients was DA3+7, and the following 58 patients received cladribine 5 mg/m2 on days 1 through 5 in addition to DA3+7 (DAC). There were no significant differences in the median age and the proportion of patients with unfavorable characteristics between the two groups. Remission after induction chemotherapy was achieved in 30/50 (60%) patients in DA3+7 and in 46/58 (79%) in DAC group (p = 0.028). The median survival in the DA3+7 group was 18 months, while in the DAC group it was not reached (p = 0.034). We confirmed results from other research groups by demonstrating improved remission induction rate and overall survival of AML patients aged 60 years or less treated with DAC induction compared with standard DA3+7 induction chemotherapy.

CD56 Expression Is an Important Prognostic Factor in Multiple Myeloma Even with Bortezomib Induction.

OBJECTIVES: In this retrospective study, we evaluated the impact of CD56, CD117, and CD28 expression on clinical characteristics and survival in newly diagnosed myeloma patients treated with bortezomib-based induction therapy. METHODS: We analyzed 110 myeloma patients. Immunophenotype was determined using panels consisting of CD19/CD38/CD45/CD56/CD138 and CD20, CD28, and CD117 were used additionally. All samples were tested for recurrent chromosomal aberrations. RESULTS: CD56, CD117, and CD28 expression rates were 71, 6, and 68%, respectively. The lack of CD56 expression was associated with light chain myeloma. The lack of CD117 expression was associated with elevated creatinine levels (p = 0.037). We discovered the correlation between CD 28 expression and female gender. The median progression-free survival (PFS) for patients with revised International Staging System stage 2 disease with CD56 expression or the lack of CD56 expression was 20.5 vs. 13.8 months (p = 0.03). In patients undergoing autologous hematopoietic stem cell transplantation (aHSCT), we found no difference in PFS and overall survival regarding the CD56 expression. We found no impact of CD117 and CD28 expression on PFS in patients regarding aHSCT. CONCLUSIONS: Induction treatment incorporating bortezomib diminishes the negative impact of the lack of CD117 expression and aberrancy of CD28 but does not overcome the negative impact of the lack of CD56 expression.

Mobilization with cyclophosphamide reduces the number of lymphocyte subpopulations in the leukapheresis product and delays their reconstitution after autologous hematopoietic stem cell transplantation in patients with multiple myeloma.

BACKGROUND: Autologous hematopoietic stem cell transplantation is considered the standard of care for younger patients with multiple myeloma. Several mobilization regimens are currently used, most commonly growth factors alone or in combination with chemotherapy. The aim of our study was to investigate the differences in lymphocyte subpopulation counts between three different mobilization regimens on collection day, in the leukapheresis product and on day 15 after autologous hematopoietic stem cell transplantation. PATIENTS AND METHODS: In total 48 patients were prospectively enrolled in three different mobilization regimens; (i) filgrastim (20), (ii) pegfilgrastim (19) and (iii) cyclophosphamide + filgrastim (9). Lymphocytes, CD16+/56+ natural killer and CD4+/CD25high T regulatory cells were determined by flow cytometry. RESULTS: We found a statistically significant difference between the mobilization regimens. Cyclophosphamide reduced lymphocyte and natural killer (NK) cell counts on collection day (lymphocytes 1.08 × 109/L; NK cells 0.07 × 109/L) compared to filgrastim (lymphocytes 3.08 × 109/L; NK cells 0.52 × 109/L) and pegfilgrastim (lymphocytes 3 × 109/L; NK cells 0.42 × 109/L). As a consequence lymphocyte and NK cell counts were also lower in the leukapheresis products following cyclophosphamide mobilization regimen (lymphocytes 50.1 × 109/L; NK cells 4.18 × 109/L) compared to filgrastim (lymphocytes 112 × 109/L; NK cells 17.5 × 109/L) and pegfilgrastim (lymphocytes 112 × 109/L; NK cells 14.3 × 109/L). In all mobilization regimens T regulatory cells increased 2-fold on collection day, regarding the base line value before mobilization. There was no difference in T regulatory cell counts between the regimens. CONCLUSIONS: Mobilization with cyclophophamide reduces the number of mobilized and collected lymphocytes and NK cells as compared to mobilization with growth factors only and results in their delayed reconstitution following autologous hematopoietic stem cell transplantation. We found no difference between filgrastim and pegfilgrastim mobilization.

Amplification of Chromosome 1q Predicts Poor Overall Survival in Newly Diagnosed Multiple Myeloma Patients.

Background: Chromosome 1q copy number alterations are common in newly diagnosed patients with multiple myeloma, and in most published studies, there is no distinction made between three copies or the addition of at least four copies. The impact of these copy number alterations on patient outcome and optimal treatment is not fully understood. Methods: We retrospectively analyzed 136 transplant eligible patients with newly diagnosed multiple myeloma from our national registry, who were treated with first autologous stem cell transplantation (aHSCT) between January 1, 2018, and December 31, 2021. The primary endpoint was overall survival. Results: Patients with at least four copies of chromosome 1q had the poorest prognosis, with an overall survival of only 28.3 months. In multivariate analysis, four copies of chromosome 1q were the only statistically significant factor for overall survival. Conclusions: Despite the use of novel agents, transplantation, and maintenance therapy, patients with a gain of four copies of chromosome 1q have a very poor survival rate. Therefore, prospective studies using immunotherapy in this patient population are necessary.

An unforeseen reality: Hemophagocytic lymphohistiocytosis following alemtuzumab treatment for a multiple sclerosis.

Alemtuzumab is a humanized monoclonal antibody indicated for treatment of highly active relapsing-remitting multiple sclerosis (HA-RRMS). It binds to CD52 antigen and produces a rapid and prolonged lymphocyte depletion followed by a different pattern of T and B cell repopulation. Among others, its adverse events are autoimmune diseases.In this article, we present a patient with HA-RRMS, who was subsequently treated with alemtuzumab and afterwards developed hemophagocytic lymphohistiocytosis (HLH). Albeit rarely, HLH can be triggered by alemtuzumab treatment.HLH can favourably respond to prompt immunosuppressant therapy.Multidisciplinary approach by a team consisting of a neurology, hematology and rheumatology specialist is needed to treat this potentially lethal condition.

Recognition of Philadelphia chromosome-like acute lymphoblastic leukemia as part of routine diagnostic work-up.

INTRODUCTION: Philadelphia chromosome (Ph)-like acute lymphoblastic leukemia (ALL) is a biologically and clinically challenging subtype of B-cell ALL which has been incorporated into the 2016 revision of the World Health classification of acute leukemia. It is independently associated with poor outcome. As it can only be reliably detected by expression profiling, it is difficult to diagnose with routine methods. Its recognition has become of greater importance due to prognostication and even more due to the new diagnostic options given by targeted therapies. There is still no standardized diagnostic test enabling its prompt recognition. Here, we introduce our approach how to detect it by combination of widely available techniques. METHODS: 179 ALL patients diagnosed in our center during the last 8 years were included. Data on immunophenotype and cytogenetics were used to select patients with potentially Ph-like ALL (65/179). CRLF2 gene rearrangement (CRLF2-r) was tested by FISH in 59/65 patients, and next-generation sequencing was done by Archer FusionPlex ALL kit in 34 patients. TSLPR expression was determined in 20 patients. RESULTS: Philadelphia chromosome-like aberrations were confirmed in 9 patients. In 10% of tested samples, CRLF2-r was confirmed. Due to a lack of material, NGS was done only in a half of potentially Ph-like cases. In 10%, other Ph-like fusions were found by NGS. CONCLUSIONS: The obtained frequencies, and genetic and patients' characteristics are in concordance with the literature data, ensuring a reliable detection of this challenging ALL subtype. The proposed algorithm allows detection of Ph-like ALL at reasonable cost and acceptable workload.

Targeting Autophagy Triggers Apoptosis and Complements the Action of Venetoclax in Chronic Lymphocytic Leukemia Cells.

Continuous treatment of patients with chronic lymphocytic leukemia (CLL) with venetoclax, an antagonist of the anti-apoptotic protein Bcl-2, can result in resistance, which highlights the need for novel targets to trigger cell death in CLL. Venetoclax also induces autophagy by perturbing the Bcl-2/Beclin-1 complex, so autophagy might represent a target in CLL. Diverse autophagy inhibitors were assessed for cytotoxic activities against patient-derived CLL cells. The AMPK inhibitor dorsomorphin, the ULK1/2 inhibitor MRT68921, and the autophagosome-lysosome fusion inhibitor chloroquine demonstrated concentration-dependent and time-dependent cytotoxicity against CLL cells, even in those from hard-to-treat patients who carried del(11q) and del(17p). Dorsomorphin and MRT68921 but not chloroquine triggered caspase-dependent cell death. According to the metabolic activities of CLL cells and PBMCs following treatments with 10 µM dorsomorphin (13% vs. 84%), 10 µM MRT68921 (7% vs. 78%), and 25 µM chloroquine (41% vs. 107%), these autophagy inhibitors are selective toward CLL cells. In these CLL cells, venetoclax induced autophagy, and addition of dorsomorphin, MRT68921, or chloroquine showed potent synergistic cytotoxicities. Additionally, MRT68921 alone induced G2 arrest, but when combined with venetoclax, it triggered caspase-dependent cytotoxicity. These data provide the rationale to target autophagy and for autophagy inhibitors as potential treatments for patients with CLL.

Surgery results in low relapse and progression rates in extramedullary plasmacytoma of the head and neck: A case cohort and review of the literature.

Extramedullary plasmacytoma of the head and neck is a rare indolent neoplasm. Radiotherapy is often the preferred treatment option with excellent local control and survival. The risk of local recurrence or transformation to multiple myeloma is 10-30%. In our case-cohort, thorough, sensitive initial evaluation for disseminated clonal disease and the incorporation of surgery led to excellent results with no recurrences or systemic progression.

18F-FDG PET/CT for Staging and Evaluation of Therapy in a Patient With Unusual Hairy Cell Leukemia Presentation.

Hairy cell leukemia is a rare hematologic malignancy characterized by splenomegaly, pancytopenia, and susceptibility to infections. We report a case of a 66-year-old man, diagnosed with hairy cell leukemia, without severe cytopenias and splenomegaly, but with an extensive pathological retroperitoneal mass and infiltration of the spleen and skeletal involvement. All findings were highly avid on pretreatment F-FDG PET/CT scan. Treatment response evaluation F-FDG PET/CT scan showed normalization of FDG uptake on all previously pathological sites.

Filgrastim-alone versus pegylated filgrastim-alone for autologous peripheral blood stem cells mobilization in newly diagnosed multiple myeloma patients.

BACKGROUND: Autologous hematopoietic stem cell transplantation (aHSCT) is the recommended standard upfront treatment for transplant eligible myeloma patients. Considering possible complications related to chemotherapy-cytokine mobilization, cytokine-alone mobilization is often used. We compared mobilization with filgrastim alone to pegfilgrastim alone in newly diagnosed myeloma patients after induction treatment with bortezomib and dexamethasone. The comparison was made between peripheral blood stem cell (PBSC) yields, number of apheresis, hematopoietic stem cell subsets, and time to neutrophil and platelet engraftment after aHSCT. METHODS: A total of 42 myeloma patients were prospectively enrolled in the study: 21 received filgrastim, 21 pegfilgrastim. Flow cytometry was used to determine the number of PBSC, myeloid, lymphoid, and megakaryocyte precursors in peripheral blood and apheresis product on day 1 of apheresis. RESULTS: The median number of collected PBSC was 5.05 × 106/kg in the filgrastim and 4.66 × 106/kg in the pegfilgrastim group (p = 0.428). The median number of apheresis was 2.5 in the filgrastim and 2 in the pegfilgrastim group (p = 0.901). The number of megakaryocyte precursors in peripheral blood was significantly higher in the filgrastim group, but not in the apheresis products. There were no statistically significant differences in the myeloid and lymphoid precursors in the peripheral blood and in the apheresis products. The median time to neutrophil and platelet engraftment was 13 days and 16.5 days for filgrastim and 13 days and 16 days for pegfilgrastim group. CONCLUSIONS: We can conclude that pegfilgrastim alone is at least equally successful as filgrastim alone for the PBSC mobilization in newly diagnosed myeloma patients.