Hyperleukocytosis and leukostasis: management of a medical emergency

Prophylactic red blood cell transfusions in children and neonates with cancer: An evidence-based clinical practice guideline

BACKGROUND

Red blood cell (RBC) transfusions play an important role in supportive care in children and neonates with cancer. However, in current clinical practice, evidence-based recommendations are lacking on when to administer prophylactic RBC transfusions. To address this gap, a clinical practice guideline (CPG) was developed to systematically review the available evidence and provide recommendations for clinicians.

METHODS

A systematic literature review in three databases was conducted. The GRADE methodology was used to assess, extract, and summarize the evidence. A multidisciplinary panel of 21 professionals was assembled to ensure comprehensive expertise. If there was insufficient evidence in children with cancer, additional evidence was gathered in general pediatric or adult oncology guidelines, or the panel utilized shared expert opinion to develop a comprehensive CPG. Multiple in-person meetings were conducted to discuss evidence, complete evidence-to-decision frameworks, and formulate recommendations.

RESULTS

Four studies including 203 children with all types of cancer, met the inclusion criteria. The expert panel assessed all evidence and translated it into recommendations. In total, 47 recommendations were formulated regarding RBC transfusions in children and neonates with cancer. For instance, specific thresholds for prophylactic RBC transfusions were recommended for children and neonates with cancer who have sepsis, are on ECMO, or are undergoing radiotherapy.

CONCLUSION

This clinical practice guideline presents evidence-based recommendations regarding RBC transfusions in children and neonates with cancer. By providing these recommendations, we aim to guide clinicians and contribute to improving outcomes for children and neonates with cancer.

Pseudohyperkalemia in pediatric patients with newly diagnosed hematological malignancies

Patients with newly diagnosed hematological malignancies often present with a considerable cellular burden, leading to complications including hyperkalemia. However, pseudohyperkalemia, arising from in vitro cell lysis, can pose challenges in clinical practice. Although pseudohyperkalemia is frequently reported in adult hematological malignancies, its occurrence in pediatric patients is underreported, and its incidence in this demographic remains unclear. We retrospectively reviewed the medical records of pediatric patients who received a new diagnosis of hematological malignancies from 2011 to 2022 at Taichung Veterans General Hospital. Hyperkalemia was defined by a serum or plasma potassium level exceeding 5.5 mEq/L. Pseudohyperkalemia was defined by 1) a potassium decrease of over 1 mEq/L in within 4 h without intervention or 2) the absence of electrocardiography changes indicative of hyperkalemia. Cases with apparent red blood cell hemolysis were excluded. A total of 157 pediatric patients with a new diagnosis of hematological malignancies were included, 14 of whom exhibited hyperkalemia. Among these 14 cases, 7 cases (4.5%) were of pseudohyperkalemia. This rate increased to 21.2% in patients with initial hyperleukocytosis. Pseudohyperkalemia was associated with a higher initial white blood cell count and lower serum sodium level. All episodes of pseudohyperkalemia occurred in the pediatric emergency department, where samples were obtained as plasma, whereas all true hyperkalemia cases were observed in the ordinary ward or intensive care unit, where samples were obtained as serum. Timely recognition of pseudohyperkalemia is crucial to avoiding unnecessary potassium-lowering interventions in pediatric patients with newly diagnosed hematological malignancies.

Therapeutic Leukapheresis in a Pediatric Acute Myeloid Leukemia (AML) Crisis as a Critical Life-Saving Adjunctive Therapy: A Case Report

Hematological malignancies can present with severe complications, including hyperleukocytosis, which demands immediate intervention due to elevated leukocyte counts that increase blood viscosity and cause microcirculatory abnormalities. This case report highlights the critical role of therapeutic leukapheresis in managing a pediatric patient with acute myeloid leukemia (AML) in crisis. A six-year-old male child presented with symptoms of severe hyperleukocytosis, including high-grade fever, respiratory distress, and a significant leukocyte count (555,820/µL). Immediate interventions included intravenous hydration, antibiotics, steroids, and non-invasive ventilation, followed by therapeutic leukapheresis. The leukapheresis procedure successfully reduced the leukocyte count by 81% without any adverse events. Post-procedure treatment with etoposide further decreased the leukocyte count, leading to symptomatic improvement and stabilization of the patient. The patient was later discharged in stable condition and continued receiving induction-phase chemotherapy. This case underscores the efficacy and necessity of leukapheresis as a life-saving adjunctive therapy in pediatric AML crises, demonstrating its role in rapidly reducing leukocyte counts and preventing life-threatening complications.

Outcomes of Patients With Newly Diagnosed AML and Hyperleukocytosis

PURPOSE

AML presenting with hyperleukocytosis is associated with poor outcomes. We aim to understand the factors associated with early mortality and overall survival (OS) to help guide management and improve early mortality.

METHODS

We retrospectively reviewed data from 129 consecutive patients with newly diagnosed AML and a WBC count ≥100 × 109/L between January 2010 and April 2020. Logistic regression models estimated odds ratios for 4-week mortality. Cox proportional hazard models estimated hazard ratios for OS.

RESULTS

The median age was 65 years (range, 23-86); the median WBC was 146 × 109/L (range, 100-687). Seventy-five (58%) patients had clinical leukostasis (CL). FLT3, NPM1, and RAS pathway mutations were detected in 63%, 45%, and 27% of patients, respectively. Cytoreduction consisted of hydroxyurea in 124 (96%) patients, cytarabine in 69 (54%), and leukapheresis in 31 (24%). The cumulative 4-week and 8-week mortality rates were 9% and 13%, respectively, all in patients age 65 years and older. By multivariate analysis, older age, CL, and thrombocytopenia <40 × 109/L were independently associated with a higher 4-week mortality rate. After a median follow-up of 49.4 months, the median OS was 14.3 months (95% CI, 7 to 21.6), with 4-year OS of 29%. Age 65 years and older, CL, tumor lysis syndrome, elevated LDH ≥2,000 U/L, elevated lactate ≥2.2 mmol/L, and poor-risk cytogenetics were independent factors associated with worse OS.

CONCLUSION

Hyperleukocytosis is a life-threatening hematologic emergency. Early recognition and intervention including cytoreduction, blood product support, antibiotics, and renal replacement therapy may help mitigate the risk of morbidity and early mortality.

Redefining hyperviscosity in acute leukemia: Potential implications for red cell transfusions in the microvasculature

Hyperleukocytosis is an emergency of acute leukemia leading to blood hyperviscosity, potentially resulting in life-threatening microvascular obstruction, or leukostasis. Due to the high number of red cells in the circulation, hematocrit/hemoglobin levels (Hct/Hgb) are major drivers of blood viscosity, but how Hct/Hgb mediates hyperviscosity in acute leukemia remains unknown. In vivo hemorheological studies are difficult to conduct and interpret due to issues related to visualizing and manipulating the microvasculature. To that end, a multi-vessel microfluidic device recapitulating the size-scale and geometry of the microvasculature was designed to investigate how Hct/Hgb interacts with acute leukemia to induce "in vitro" leukostasis. Using patient samples and cell lines, the degree of leukostasis was different among leukemia immunophenotypes with respect to white blood cell (WBC) count and Hct/Hgb. Among lymphoid immunophenotypes, severe anemia is protective against in vitro leukostasis and Hct/Hgb thresholds became apparent above which in vitro leukostasis significantly increased, to a greater extent with B-cell acute lymphoblastic leukemia (ALL) versus T-cell ALL. In vitro leukostasis in acute myeloid leukemia was primarily driven by WBC with little interaction with Hct/Hgb. This sets the stage for prospective clinical studies assessing how red cell transfusion may affect leukostasis risk in immunophenotypically different acute leukemia patients.

Successful Therapeutic Leukapheresis for Chronic Myeloid Leukemia Identified by Persistent Erection: A Case Report

Cytoreduction in leukostasis can be achieved using leukapheresis. We report a case of chronic myeloid leukemia (CML) identified by a persistent erection, which was successfully treated using the Spectra Optia®︎ apheresis system. A 29-year-old male presented with an erection for 12 hours without identified triggers and no improvement despite penile corpus cavernosum puncture. His white blood cell count was 458,930/μL. A diagnosis of CML-induced persistent erection with secondary hyperleukocytosis was established. Following an emergency bilateral penile corpus cavernosum incision (distal shunting), he received hydroxyurea and febuxostat. Persistent erection resolved after leukapheresis for two consecutive days. Rapid leukocyte count reduction can effectively address leukostasis in CML without major complications.

The ISTH DIC-score predicts early mortality in patients with non-promyelocitic acute myeloid leukemia

Coagulation disorders frequently complicate the clinical course of acute myeloid leukemia (AML) patients. This study examined the frequency and prognostic significance, with regards of early mortality, of the presence of overt disseminated intravascular coagulation (DIC) at AML diagnosis and its correlation with clinical and biological characteristics. A retrospective analysis of 351 newly diagnosed non-promyelocytic AML patients was conducted, utilizing the 2018 ISTH DIC-Score criteria to evaluate the presence of overt DIC at AML onset. The study cohort had a median age of 65 years with a predominance of male gender (59 %). Overt DIC was present in 21 % of cases and was associated with advanced age, comorbidities, poor performance status, hyperleukocytosis, LDH levels, NPM1 mutations, expression of CD33 and CD4, and lack of expression of CD34. With a median follow-up of 72 months (3-147 months), the 6-year overall survival (OS) was 17.4 %, with patients having overt DIC showing significantly poorer outcomes (7.2 % compared to 20.3 % of those without DIC, p < 0.001). Patients with overt DIC showed markedly high early mortality rates at 30 (42.5 % vs 8 %), 60 (49.3 % vs 16.9 %), and 120 days (64.4 % vs 25.6 %) from disease onset. In multivariate analysis overt DIC retained its independent prognostic value for early mortality. In conclusion, the prevalence and clinical relevance of DIC in non-promyelocytic AML is not negligible, underlining its potential as an unfavorable prognostic marker. In newly diagnosed patients with AML, early recognition and measure to counteract coagulation disturbances might help mitigate the elevated mortality risk associated with DIC.

Red cell exchange for rapid leukoreduction in adults with hyperleukocytosis and leukostasis

ABSTRACT

We show that red cell exchange (RCE) treats hyperleukocytosis in acute leukemia. RCE provided similar leukoreduction to standard therapeutic leukoreduction and could be superior in patients with severe anemia or monocytic leukemias or when requiring rapid treatment.

Effectiveness of leukapheresis on early survival in acute myeloid leukemia: An observational propensity score matching cohort study

BACKGROUND

The association between leukapheresis (LK) as a treatment option for hyperleukocytosis (HL) in patients with acute myeloid leukemia (AML) remains controversial.

METHODS

Data were extracted from the electronic medical record for 2801 patients with AML between April 2009 and December 2019. LK was performed when the leukocyte count was ≥100 × 109 /L at the time initial bone marrow examination.

RESULTS

A comparison between the patients with HL in the non-LK (n = 1579) and LK (n = 208) groups revealed survival probabilities (%) of 93.2% and 90.4% (P = .130) for day 30 (D30), 85.4% and 84.2% (P = .196) for D60, and 83.6% and 80.8% (P = .258) for D90, respectively. After propensity score matching, a comparison between the patients with HL in the non-LK (n = 192) and LK (n = 192) groups revealed survival probabilities (%) of 83.9% and 91.2% (P = .030) for D30, 75.0% and 84.9% (P = .015) for day 60 (D60), and 62.4% and 81.3% (P = .034) for day 90 (D90), respectively. After D150, the observed effect of LK appeared to be mitigated without a survival benefit.

DISCUSSION

LK was associated with improved early survival outcomes at D30, D60, and D90 among patients with AML exhibiting HL. Thus, it may be considered a treatment option for reducing cell mass in such patients.

Genetic mutations and leukapheresis in acute myeloid leukemia: is there a link?

Acute myeloid leukemia is the most common acute leukemia in adults and up to 20% of patients present with hyperleukocytosis at the onset of the disease. The therapeutic approach involves medical support, cytoreductive treatment, and/or leukapheresis. Despite WBC count greater than 100.000/μL, not all patients develop symptoms. To clarify the role of leukapheresis in the setting of hyperleukocytotic AML, we aimed to find associations between AML morphologic subtypes and molecular alterations on presence or absence of leukostasis symptoms (and hence therapeutic vs prophylactic leukapheresis) and clinical outcomes in the cohort of 41 patients at our single center who underwent leukapheresis for hyperleukocytotic AML. There was a trend for increased WBC count, 30-day mortality, M4-M5 AML subtypes, and number of leukapheresis procedures performed in symptomatic hyperleukocytotic pts. No molecular marker was significantly associated with presence or absence of leukostasis symptoms due to small sample size, though there was a trend for increased NPM1-mutated and NPM1 + FLT3-mutated AML in asymptomatic patients and a greater proportion of symptomatic patients who were negative for all assessed molecular alterations. In conclusion, leukapheresis combined with cytoreductive treatment represents a synergic and efficient approach in the management of hyperleukocytosis especially in symptomatic patients considering the higher mortality independently from the presence of specific clonal markers whose distribution among the two groups may result more considerable with a higher number of patients.

Leukostasis With Isolated Central Nervous System Involvement in Chronic Phase of Chronic Myelogenous Leukemia

Chronic myelogenous leukemia (CML) is a hematologic malignancy with unique significance to the field of hematology and oncology, specifically due to the development of tyrosine kinase inhibitors (TKIs). CML often presents with nonspecific symptoms, and the quality of life in patients with CML has drastically improved as a result of TKIs. However, complications of CML including the risk of transforming into life-threatening blast crises continue to exist. Further, as most patients are asymptomatic in the chronic phase, patients often present with serious complications associated with noncompliance to TKIs. For example, central nervous system (CNS) manifestations of CML have been reported, both as the initial presentation of undiagnosed CML and as known complication of uncontrolled CML. Hyperleukocytosis is a manifestation of uncontrolled CML and leukostasis is a complication, occurring in cases of acute myeloid leukemia (AML). Here we present a rare case of leukostasis in a patient with known CML presenting on computed tomography (CT) as intracranial masses in the chronic phase. Our goal is to discuss this rare case of leukostasis in adult CML and describe its management.

An isoform of the giant protein titin is a master regulator of human T lymphocyte trafficking

Response to multiple microenvironmental cues and resilience to mechanical stress are essential features of trafficking leukocytes. Here, we describe unexpected role of titin (TTN), the largest protein encoded by the human genome, in the regulation of mechanisms of lymphocyte trafficking. Human T and B lymphocytes express five TTN isoforms, exhibiting cell-specific expression, distinct localization to plasma membrane microdomains, and different distribution to cytosolic versus nuclear compartments. In T lymphocytes, the LTTN1 isoform governs the morphogenesis of plasma membrane microvilli independently of ERM protein phosphorylation status, thus allowing selectin-mediated capturing and rolling adhesions. Likewise, LTTN1 controls chemokine-triggered integrin activation. Accordingly, LTTN1 mediates rho and rap small GTPases activation, but not actin polymerization. In contrast, chemotaxis is facilitated by LTTN1 degradation. Finally, LTTN1 controls resilience to passive cell deformation and ensures T lymphocyte survival in the blood stream. LTTN1 is, thus, a critical and versatile housekeeping regulator of T lymphocyte trafficking.

Safety and performance of the Spectra Optia apheresis system for white blood cell depletion in patients with elevated white blood cell counts

BACKGROUND

For the past 30 years, white blood cell depletion (WBCD) or leukocytapheresis has been conducted to rapidly reduce excessive circulating white blood cell (WBC) concentrations in patients at risk for or with symptoms of leukostasis due to hyperleukocytosis. The goal of leukocytapheresis is to prevent or treat acute complications from leukostasis, thereby enabling patients to receive potentially curative chemotherapy.

METHODS

This report details the results from a retrospective and a prospective clinical study conducted in the European Union and the People's Republic of China, which assessed the use of the Spectra Optia Apheresis System for leukocytapheresis in patients with hyperleukocytosis. The primary objective of both studies was to the assess the safety and performance of the WBCD procedure in patients with elevated WBC counts.

RESULTS

Data were collected from 72 participants completing 87 WBCD procedures. The mean percent change in participant WBC counts post-procedure was 50.3 ± 21.2% and the collection efficiency (CE1) of the WBCD procedures was 53.7 ± 19.8%. Sixty-one participants (95.3%) experienced a total of 279 adverse events (AEs) with the majority of the AEs related to post-procedure changes in laboratory values, which is an anticipated AE in this patient population.

CONCLUSION

The data collected within these studies indicate that the WBCD procedure is safe and well tolerated in patients with hyperleukocytosis as evaluated by percent decrease in WBC count, CE1, and AE incidence.

Repeated small-volume exchange transfusion for hyperleukocytosis in pediatric acute leukemia: A retrospective analysis

Introduction

Leukapheresis reduces hyperleukocytosis in children with acute leukemia. Although the usefulness of this procedure is under debate, a repeated small-volume exchange transfusion along with leukapheresis yielded satisfactory results.

Methods

Forty-seven patients with acute leukemia [32 acute lymphocytic leukemia (ALL) and 15 acute myeloblastic leukemia (AML)] were enrolled between January 2017 and June 2022 and underwent repeated small-volume exchange transfusion. The following were measured: demographic and clinical characteristics, time of the procedure, PWBC (peripheral white blood cell) count, hemoglobin, platelet count, blood biochemistry, electrolytes, coagulation, leukostasis, TLS (tumor lysis syndrome), DIC (disseminated intravascular coagulopathy), adverse events (AEs), and serious AEs (SAEs).

Results

The demographic and clinical characteristics were not significantly different between ALL and AML patients, but differences were observed in PWBC counts (424.2 ± 135.6 vs. 223.8 ± 58.0 × 109/L). The procedures needed 3-8 processes, and the average procedure time was not significantly different between ALL and AML. The PWBC count gradually reduced to <100 × 109/L; hemoglobin, platelet count, K+, Na+, and Ca2+ were unchanged. Alanine aminotransferase, aspartate aminotransferase, total bilirubin, blood urea nitrogen, creatinine, troponin-I, creatine kinase-MB, prothrombin time, and activated partial thromboplastin time maintained normal or recovered from abnormal ranges. The manifestations of leukostasis, TLS, and DIC improved or disappeared. No AEs and SAEs occurred. The required total blood volume was based on initial PWBC count, manifestations of leukostasis, and age.

Conclusions

Our finding suggests that repeated small-volume exchange transfusion is effective and safe for treating hyperleukocytosis in children with acute leukemia.

Post-remission outcomes in AML patients with high hyperleukocytosis and inaugural life-threatening complications

Introduction

Patients with hyperleukocytic (HL) acute myeloid leukemia (AML) are at higher risk of early death. Initial management of these patients is challenging, not fully codified and heterogenous. Retrospective studies showed that several symptomatic measures might decrease early death rate but long-term data are scarce. We aimed to analyze whether the therapeutic measures carried out urgently at diagnosis may influence the outcome among HL AML patients having achieved who survived inaugural complications.

Methods

We retrospectively reviewed all medical charts from patients admitted to Saint-Louis Hospital between January, 1^st 1997 and December, 31st 2018 with newly diagnosed AML and white blood cell (WBC) count above 50x10⁹/L. Outcome measures were cumulative incidence of relapse (CIR), treatment-related mortality (TRM) defined as relapse-free death, and overall survival. Univariate and multivariate analyses were performed using Cox proportional hazards models.

Results

A total of 184 patients with HL AML in complete remission (CR) were included in this study. At 2 years after CR. 62.5% of patients were alive, at 5 years, cumulated incidence of relapse was 55.8%. We found that every therapeutic measure, including life-sustaining therapies carried out in the initial phase of the disease, did not increase the relapse risk. The use of hydroxyurea for more than 4 days was associated with a higher risk of relapse. At the end of the study, 94 patients (51.1%) were still alive including 23 patients out of 44 aged less than 60 yo that were able to return to work.

Conclusion

We show that the use of emergency measures including life sustaining therapies does not come at the expense of a higher risk of relapse or mortality, except in the case of prolonged use of hydroxyurea. Patients with HL AML should be able to benefit from all available techniques, regardless of their initial severity.

Effectiveness and safety of leukapheresis in hyperleukocytic leukemias: a retrospective multicenter study

Leukapheresis is an effective adjuvant therapy for leukemia patients with hyperleukocytosis, but few studies have reported recent data with modern modalities and comparisons among different leukemia types. We conducted a retrospective study on leukapheresis among 420 patients with AML, ALL and CML in four local centers. WBC counts decreased significantly (p < 0.001) postleukapheresis in all three cohorts. Clearance efficiency was higher in acute leukemia patients than CML patients (p < 0.01). Concomitant leukocytoreduction drugs improved WBC reduction only in AML patients (p < 0.05). Leukocyte, hemoglobin and platelet levels preleukapheresis might affect the clearance efficiency in AML and/or ALL patients. Hematological toxicities were the major concerns, but most of them were mild, and only 11 patients died of all causes within one week postleukapheresis. In conclusion, leukapheresis can safely reduce the leukemic burden, especially for patients with acute leukemias.

The emerging oral pathogen, Filifactor alocis, extends the functional lifespan of human neutrophil

Periodontitis is a chronic inflammatory infectious disease that affects the integrity of tooth‐supporting tissues and has adverse systemic consequences. Advances in sequencing technologies have uncovered organisms that are exclusively found in high numbers in periodontal lesions, such as the gram‐positive anaerobic rod, Filifactor alocis. F. alocis can manipulate neutrophil effector functions, which allows the organism to survive within these granulocytes. Several neutrophil functions have been tested in the context of F. alocis challenge, but the effect of the organism on neutrophil apoptosis is still unknown. RNA sequencing of human neutrophils challenged with F. alocis showed that apoptosis pathways were differentially regulated. Compared to media‐cultured controls, F. alocis‐challenged neutrophils maintain their nuclear morphology, do not stain for Annexin V or 7‐AAD, and have decreased DNA fragmentation. Inhibition of apoptosis by F. alocis involved reduced caspase‐3, −8, and − 9 activation and upregulation of important anti‐apoptotic proteins. Prolonged lifespan was dependent on contact through TLR2/6, and F. alocis‐challenged neutrophils retained their functional capacity to induce inflammation for longer timepoints. This is the first in‐depth characterization of neutrophil apoptotic programs in response to an oral pathogen and provides key information on how bacteria manipulate immune cell mechanisms to maintain a dysregulated inflammatory response.

Hematological Malignancies and the Kidney

The incidence of hematologic malignancies is on the rise worldwide. Kidney disease is ubiquitous in patients with hematologic malignancies, encompassing a wide spectrum of disorders involving each kidney compartment, including the vasculature, tubules, interstitium, and glomerulus, and there is significant overlap of kidney involvement with each hematologic malignancy. Vascular disorders include both microvascular and macrovascular damage, via thrombotic microangiopathy, hyperleukocytosis, hyperviscosity, and cryoglobulinemia. The tubulointerstitial compartment may be affected by prerenal azotemia and acute tubular injury, but malignant infiltration, tumor lysis syndrome, extramedullary hematopoiesis, cast nephropathy, granulomatous interstitial nephritis, and lysozymuria should be considered in certain populations. Obstructive uropathy may occur due to nephrolithiasis or retroperitoneal fibrosis. Glomerular disorders, including membranoproliferative, membranous, minimal change, and focal segmental glomerulosclerosis, can rarely occur. By understanding how each compartment may be affected, care can best be optimized for these patients. In this review, we summarize the widely varied etiologies of kidney diseases stratified by kidney compartment and hematologic malignancy, focusing on demographics, pathology, pathophysiology, mechanism, and outcomes. We conclude with common electrolyte abnormalities associated with hematologic malignancies.

The recognition and nursing management of common oncological emergencies in children

An oncological emergency may be the initial presentation of a cancer, a sign of cancer progression, or a complication of cancer treatment. The most frequently encountered paediatric oncological emergencies include neutropenic sepsis, hyperleukocytosis, brain tumours presenting with raised intracranial pressure, tumour lysis syndrome and superior mediastinal syndrome. These are all life-threatening conditions that require urgent recognition and management. Health professionals working in an emergency department (ED) are likely to be involved in managing these children. This article brings together the current guidance and recommendations for these specific emergencies. It also includes two case studies that demonstrate the challenges health professionals can face while managing these situations. It is important that health professionals have an acute awareness of oncological emergencies. Confidence in recognising the presentations, diagnoses and initial management are essential because these conditions may be life-threatening and time critical.

Hyperleukocytic Acute Leukemia Circulating Exosomes Regulate HSCs and BM-MSCs

Hyperleukocytic acute leukemia (HLAL) circulating exosomes are delivered to hematopoietic stem cells (HSCs) and bone marrow mesenchymal stem cells (BM-MSCs), thereby inhibiting the normal hematopoietic process. In this paper, we have evaluated and explored the effects of miR-125b, which is carried by HLAL-derived exosomes, on the hematopoietic function of HSCs and BM-MSCs. For this purpose, we have isolated exosomes from the peripheral blood of HLAL patients and healthy volunteers. Then, we measured the level of miR-125b in exosomes cocultured exosomes with HSCs and BM-MSCs. Moreover, we have used miR-125b inhibitors/mimic for intervention and then measured miR-125b expression and colony forming unit (CFU). Apart from it, HSC and BM-MSC hematopoietic-related factors α-globulin, γ-globulin, CSF2, CRTX4 and CXCL12, SCF, IGF1, and DKK1 expression were measured. Evaluation of the miR-125b and BAK1 targeting relationship, level of miR-125b, and expression of hematopoietic-related genes was performed after patients are treated with miR-125b mimic and si-BAK1. We have observed that miR-125b was upregulated in HLAL-derived exosomes. After HLAL-exosome acts on HSCs, the level of miR-125b is upregulated, reducing CFU and affecting the expression of α-globulin, γ-globulin, CSF2, and CRCX4. For BM-MSCs, after the action of HLAL-exo, the level of miR-125b is upregulated and affected the expression of CXCL12, SCF, IGF1, and DKK1. Exosomes derived from HLAL carry miR-125b to target and regulate BAK1. Further study confirmed that miR-125b and BAK1mimic reduced the expression of miR-125b and reversed the effect of miR-125b mimic on hematopoietic-related genes. These results demonstrated that HLAL-derived exosomes carrying miR-125b inhibit the hematopoietic differentiation of HSC and hematopoietic support function of BM-MSC through BAK1.

Leukapheresis and Hyperleukocytosis, Past and Future

Hyperleukocytosis is a hematologic crisis caused by excessive proliferation of leukemic cells and has a relatively high early mortality due to a series of severe complications. Therefore, prompt and effective intervention is required. Leukapheresis performed using apheresis equipment to separate leukocytes from peripheral blood, at the same time returns autologous plasma, platelets and erythrocytes to the patient, is applied clinically for the treatment of hyperleukocytosis. Leukapheresis not only removes excessive leukocytes rapidly and corrects metabolic abnormalities but also alleviates the symptoms of leukostasis. In addition, the procedure of leukapheresis is generally well tolerated. Leukapheresis has become one of the most imperative adjuvant therapies to treat hyperleukocytosis, especially in the patient who was not inappropriate to cytoreduce with Ara-C or hydroxyurea. In this review, we present the background of leukapheresis development and highlight its clinical application in hyperleukocytic leukemia patients.

Leukapheresis Does Not Improve Early Survival Outcome of Acute Myeloid Leukemia with Leukostasis Patients - A Dual-Center Retrospective Cohort Study

Introduction

Leukostasis is a medical emergency with high mortality which often occurs in acute myeloid leukemia patients with hyperleukocytosis. One of the therapies that can be used for leukostasis in acute myeloid leukemia is leukapheresis. However, whether leukapheresis can provide better survival benefit when compared with patients not receiving leukapheresis is still unclear. Hence, we aimed to evaluate the effect of chemotherapy plus leukapheresis combination versus chemotherapy only on 28-day survival of acute myeloid leukemia patients with leukostasis.

Methods

This study was a dual-center retrospective cohort using secondary data from medical records collected from November 2018 to March 2019. Inclusion criteria were adult patients aged 18 years old or above, diagnosed with acute leukemia with hyperleukocytosis status defined by WBC count greater than 100,000/uL, and with symptoms of leukostasis. One-month survival analysis was conducted using Kaplan–Meier curve method. Univariate and multivariate analyses were then conducted using Cox proportional hazards model to obtain value of hazard ratio (HR) with a 95% confidence interval (CI).

Results

A total of 38 patients were obtained for analysis. The median overall survival was 25 days (95% CI: 17.001–32.999 days) in the chemotherapy only group and 20 days (95% CI: 1.497–38.503) in the chemotherapy with leukapheresis group. The use of leukapheresis did not affect 28-day survival (HR: 1.140; 95% CI: 0.396–3.283; p value: 0.809) and 7-day survival (HR: 1.073; 95% CI: 0.277–4.152; p value: 0.919). In the multivariate analysis, age ≥60 years, blast percentage ≥90%, creatinine ≥1.4 mg/dL, and presence of disseminated intravascular coagulation were associated with worse 28-day survival.

Conclusion

AML patients with leukostasis who received both chemotherapy and leukapheresis did not have better 28-day survival and 7-day survival when compared with patients receiving chemotherapy only. Old age, high blast percentage, high creatinine, and presence of disseminated intravascular coagulation were prognostic factors for worse 28-day survival.

Clinical characteristics of tumor lysis syndrome in childhood acute lymphoblastic leukemia

Tumor lysis syndrome (TLS) is a common and fatal complication of childhood hematologic malignancies, especially acute lymphoblastic leukemia (ALL). The clinical features, therapeutic regimens, and outcomes of TLS have not been comprehensively analyzed in Chinese children with ALL. A total of 5537 children with ALL were recruited from the Chinese Children’s Cancer Group, including 79 diagnosed with TLS. The clinical characteristics, treatment regimens, and survival of TLS patients were analyzed. Age distribution of children with TLS was remarkably different from those without TLS. White blood cells (WBC) count ≥ 50 × 10⁹/L was associated with a higher risk of TLS [odds ratio (OR) = 2.6, 95% CI = 1.6–4.5]. The incidence of T-ALL in TLS children was significantly higher than that in non-TLS controls (OR = 4.7, 95% CI = 2.6–8.8). Hyperphosphatemia and hypocalcemia were more common in TLS children with hyperleukocytosis (OR = 2.6, 95% CI = 1.0–6.9 and OR = 5.4, 95% CI = 2.0–14.2, respectively). Significant differences in levels of potassium (P = 0.004), calcium (P < 0.001), phosphorus (P < 0.001) and uric acid (P < 0.001) were observed between groups of TLS patients with and without increased creatinine. Laboratory analysis showed that older age was associated with a higher level of creatinine. Calcium level was notably lower in males. WBC count, lactate dehydrogenase, and creatinine levels were significantly higher in T-ALL subgroup, whereas procalcitonin level was higher in B-ALL children. Older age, infant, a higher level of WBC and T-ALL were risk factors TLS occurrence. Hyperleukocytosis has an impact on the severity of TLS, while renal injury may be an important feature in the process of TLS.

Effect of prophylactic leukapheresis on early mortality and overall survival in acute leukemia patients with hyperleukocytosis

Hyperleukocytosis has been associated with early mortality owing to the presence of complications including leukostasis, tumor lysis syndrome (TLS), and disseminated intravascular coagulation (DIC). Leukapheresis is a fast and effective cytoreductive procedure that removes leukocytes from the peripheral circulation. This single-center, retrospective, and observational study included 32 patients diagnosed with acute leukemia who underwent leukapheresis due to hyperleukocytosis between 2014 and 2020. This study primarily aimed to investigate the effect of prophylactic leukapheresis on early mortality and overall survival (OS). In the symptomatic group, seven and two patients died in the first and second weeks, respectively. In the prophylactic leukapheresis group, two and one patients died in the first and second weeks (p = 0.792), respectively. OS was significantly longer in the prophylactic leukapheresis group (p = 0.004). The leukapheresis procedure appears to be effective on early mortality and OS. Initiation of prophylactic leukapheresis before the appearance of leukostasis symptoms is effective on OS and possibly early mortality.

Intracranial Hemorrhage in a Pediatric Patient with Chronic Myeloid Leukemia in Chronic Phase: A Case Report

Chronic myeloid leukemia (CML) is an uncommon entity in pediatric patients. CML in chronic phase (CML-CP) has a relatively favorable outcome. Leukostasis occurs in 9.7% of patients with CML. One of the most serious leukostasis-related complications is intracranial hemorrhage (ICH). However, this is very rare in patients with CML-CP, and few early mortalities have been reported in CML patients with leukostasis. We report the case of a 14-year-old female patient with CML-CP who developed ICH 8 days after admission. A 14-year-old girl developed symptoms of fatigue and slight fever and was diagnosed with CML-CP. She was treated with imatinib and received low-molecular-weight heparin owing to coagulation abnormalities. However, 6 days later, she developed sensorineural hearing loss, which is a symptom of leukostasis. She received hydroxyurea to reduce her white blood cell (WBC) count, and her treatment was changed from imatinib to nilotinib. The WBC and platelet counts remained unchanged, blast counts did not increase, and mild coagulation abnormality persisted. Eight days after admission, she suddenly lost consciousness and experienced respiratory arrest. Cranial computed tomography revealed multiple ICH lesions and brain hernia. She received intensive care but was diagnosed with brain death by electroencephalography and died 14 days after hospitalization. ICH is very rare in patients with CML-CP; however, patients with leukostasis and coagulation abnormalities can develop severe hemorrhage, even in the chronic phase. Thus, it is necessary to accurately estimate the cause and provide appropriate treatment for these patients.

Acute Myeloid Leukemia: Advanced Practice Management From Presentation to Cure

Acute myeloid leukemia (AML) is the most common acute leukemia in adults, diagnosed in approximately 21,450 individuals annually in the US with nearly 11,000 deaths attributable to this disease (National Cancer Institute, 2020). Acute myeloid leukemia is a disease of the elderly, with the average age of diagnosis being 68 years old (Kouchkovsky & Abdul-Hay, 2016). It is a heterogeneous disease with widely varying presentations but universally carries a poor prognosis in the majority of those affected. Unfortunately, the 5-year overall survival rate remains poor, at less than 5% in patients over 65 years of age (Thein, Ershler, Jemal, Yates, & Baer, 2013). The landscape of AML is beginning to change, however, as new and improved treatments are emerging. Advanced practitioners (APs) are often involved in the care of these complex patients from the time of initial symptoms through diagnosis, treatment, and potentially curative therapy. It is vitally important for APs to understand and be aware of the various presentations, initial management strategies, diagnostic workup, and treatment options for patients with AML, especially in the elderly population, which until recently had few treatment options. This Grand Rounds article highlights the common presenting signs and symptoms of patients with AML in the hospital, including a discussion of the upfront clinical stability issues, oncologic emergencies, diagnostic evaluation, and current treatment options for elderly patients and those with poor performance status.

Oncologic Emergencies: Traditional and Contemporary

The recognition and management of oncologic emergencies are becoming increasingly relevant in the intensive care unit, particularly in the era of novel biologic therapies. Early recognition and multidisciplinary collaboration are essential to improving patient outcomes. This article discusses aspects of diagnosis and management for important malignancy-associated emergencies.

Respiratory Failure Due to a Large Mediastinal Mass in a 4-year-old Female with Blast Cell Crisis: A Case Report

INTRODUCTION

Symptomatic leukostasis is an exceptionally atypical presentation of blast crisis; and when coupled with an enlarged neoplastic mediastinal mass in a four-year-old female, an extremely rare and challenging pediatric emergency arises.

CASE REPORT

We present a unique case of a four-year-old female who arrived via emergency medical services in cardiopulmonary arrest with clinical and radiographic evidence suggestive of bilateral pneumothoraces, prompting bilateral chest tube placement. Further evaluation revealed a large mediastinal mass and a concurrent white blood cell count of 428,400 per milliliter (/mL) (4,400-12,900/mL), with a 96% blast differential, consistent with complications of T-cell acute lymphoblastic leukemia.

CONCLUSION

This case highlights how pulmonary capillary hypoperfusion secondary to leukostasis, coupled with a ventilation/perfusion mismatch due to compression atelectasis by an enlarged thymus, resulted in this patient's respiratory arrest. Furthermore, the case highlights how mediastinal masses in pediatric patients present potential diagnostic challenges for which ultrasound may prove beneficial.

Leukostasis in Chronic Lymphocytic Leukemia

Patient: Female, 77-year-old

Final Diagnosis: Leukostasis

Symptoms: Cough • palpitations • shortness of breath

Medication: —

Clinical Procedure: Endotracheal intubation • leukapheresis

Specialty: Hematology

Impact Of ELN Risk Stratification, Induction Chemotherapy Regimens And Hematopoietic Stem Cell Transplantation On Outcomes In Hyperleukocytic Acute Myeloid Leukemia With Initial White Blood Cell Count More Than 100 × 109/L

Background

Hyperleukocytic acute myeloid leukemia (AML) (initial white blood cell count≥100 × 10⁹/L) is a clinical emergency often accompanied by leukostasis syndrome, tumor lysis syndrome (TLS), and disseminated intravascular coagulation (DIC), with a poor clinical prognosis. The aim of this study retrospectively analyzed the clinical features of hyperleukocytic AML, focusing on high-risk factors affecting prognosis, the selection of initial induction therapy, and the impact of hematopoietic stem cell transplantation (HSCT) on prognosis.

Patients and methods

A total of 558 AML patients at our center from January 2013 to December 2017 were diagnosed, and 52 (9.32%) patients presented with hyperleukocytosis were retrospectively reviewed.

Results

The 3-year overall survival (OS) rate in the 15–39 years old and 40–60 years old group was 58.8% and 25.4%, respectively; the longest survival time in patients aged >60 years was only 8 months, and the 8-month OS rate was 8.3% (p=0.002). The 3-year OS rate of the patients in the favorable risk group, intermediate risk group and high risk group, according to the 2017 ELN risk stratification, was 50%, 28.0%, and 29.5%, respectively (p=0.374). The 3-year OS rate of patients carrying CEBPA or NPM1 mutation and those with FLT3-ITD or MLL mutation was 37.5% and 30.0%, respectively (p=0.63). The 3-year OS rate of patients employing an induction regimen of a standard IA regimen was 58.4%, and of those employing a non-standard IA regimen was 22.2% (p=0.065). The 3-year OS rate of the transplantation patients reached 73.8%, while the 9-month OS rate of patients without transplantation was 11.4% (p<0.001).

Conclusion

This study suggest that hyperleukocytosis is an independent risk factor for AML patients, regardless of the risk stratification based on cytogenetic or molecular abnormalities. Age is the main factor influencing the prognosis of hyperleukocytic AML. The use of a standard IA regimen and HSCT can significantly improve the patient’s prognosis.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Another Emergent Cause of Headache

We present a case of a subacute headache related to leukostasis secondary to accelerated chronic myeloid leukemia (CML), which required white blood cell (WBC) reduction in the emergency department. A 28-year-old male presented to the emergency department with a chronic headache found to be secondary to leukostasis from accelerated CML with a white blood cell count of 801,000 and 9% blasts. He had bilateral retinal hemorrhage and a headache associated with elevated intracranial pressure. Hydroxyurea and allopurinol were initiated in the emergency department and the patient was eventually transitioned to a tyrosine kinase inhibitor as outpatient therapy. Headaches are a frequent cause of emergency department visits, and this case illustrates another possible etiology of headache requiring emergent intervention.

A hospital based retrospective study of factors influencing therapeutic leukapheresis in patients presenting with hyperleukocytic leukaemia

Therapeutic leukapheresis is a rapid and effective method to reduce early mortality of patients with hyperleukocytic leukaemia (HLL). However, few studies on factors influencing the efficiency have been reported. In this study, 67 cases who underwent leukapheresis were retrospectively analysed and factors related to the collection efficiency of leukapheresis (CE_WBC) were also evaluated. Paired t test showed that there was a significant decrease in statistics of white blood cell (WBC) counts after apheresis. The results of two independent samples nonparametric test suggested that WBC counts, platelet (PLT) counts, haematocrit (HCT), hemoglobin (HGB), serum chlorine (Cl) and globulin (GLB) before leukapheresis correlated with the CE_WBC. Multiple linear regression analysis with background stepwise variable selection indicated that only WBC and HCT before leukapheresis had an influence on CE_WBC significantly. Kaplan-Meier analysis and Cox regression model indicated that lymphocyte (LY) and mean corpuscular hemoglobin (MCH) pre-apheresis as independent factors significantly affected the prognostic survival of patients with HLL. Moreover, platelets and red blood cell were contaminated in the product of leukapheresis. It is an urgent problem to be solved in order to realise higher efficacy and higher purity of WBC collection to improve the survival of patients with HLL through optimising instruments.