Treatment outcomes of pediatrics acute myeloid leukemia (AML) and associated factors in the country's tertiary referral hospital, Ethiopia.

BACKGROUND: Pediatric Acute Myeloid Leukemia (AML) is a major cause of morbidity and mortality in children with cancer in Africa and other developing continents. Systemic chemotherapy and effective supportive care have significantly contributed to increased survival rates of pediatric AML in developed countries reaching approximately 70%. There is a paucity of contextual data regarding overall and event-free survival outcomes in children with acute myeloid leukemia in developing countries and most centers in Africa provide palliative care. The objective of this study was to assess the overall survival, event-free survival, and associated factors in pediatric AML patients treated in Ethiopia. METHODS: This retrospective study was conducted on Pediatric AML patients treated at Tikur Anbessa Hospital between January 1, 2015, and May 30, 2022. The socio-demographic profile of patients, the clinical characteristics, the biochemical and morphological subtypes of AML were analyzed using SPSS version 25. The Kaplan-Meier survival curve was used to estimate the probabilities of overall and event-free survival. Statistical significance was set at p < 0.05. RESULTS: A total of 92 children with AML were included in this study. The median age at diagnosis was 7 years (interquartile range: 5-10 years) with a slight male predominance. The median duration of symptoms was one month. Neutropenic fever (56, 86.2%) was the most common complication during treatment. About 29.3% of the patients succumbed to early death. The corresponding 1-year and 3-year OS probabilities were 28.2% and 23% respectively. The median event-free survival time for all pediatric AML patients was one-month (95% CI: 0.77-1.23). The determinants of poorer survival outcomes were FAB subtype, type of protocol used, and signs of CNS involvement (p < 0.05). CONCLUSION: The survival rates of children from AML were low in the study setting. More than 25% of AML patients succumbed to early death, and febrile neutropenia was the most common complication. Effective supportive and therapeutic measures should be taken to manage febrile neutropenia and to prevent early death in AML patients.

Biological impact of manual blood exchange in malignant Bordetella pertussis infection in infants.

BACKGROUND AND OBJECTIVES: Manual blood exchange (MBE) is a leukoreduction therapy for hyperleukocytosis in Bordetella spp. INFECTION: We describe the impact of BE on clinical and biological parameters in critically ill children with malignant pertussis. MATERIALS AND METHODS: This is a monocentric retrospective review of patients with malignant pertussis infection treated with MBE. It describes the evolution of haemodynamic, ventilatory, haematologic and metabolic characteristics before and after MBE. RESULTS: Between January 2006 and December 2021, nine patients (median age 43 days, range: 13-80 days) had 16 MBE for malignant pertussis. All patients were mechanically ventilated, and 7/9 patients developed pulmonary hypertension during their paediatric intensive care unit (PICU) stay. Overall, 3/9 patients survived, and the mean PICU length of stay was 8.5 days (range: 1-52 days). We found a significant reduction of the leukocyte count (pre-MBE: 61.8 G/L [interquartile range (IQR): 55.8-74.8] vs. post-MBE: 19.4 G/L [IQR: 17.7-24.1]; p ≤ 0.001) and significant oxygenation improvement (pre-MBE SpO2/FiO2: 190 [IQR: 106-200] vs. post-MBE SpO2/FiO2: 242 [IQR: 149-250]; p = 0.03). The main side effects were a significant reduction of thrombocytes (pre-MBE: 411 G/L [IQR: 166.5-563.5] vs. post-MBE: 66 G/L [IQR: 46-82.5]; p = <0.001) and of ionized calcium (iCa) (pre-MBE iCa: 1.3 [IQR: 1.22-1.37] vs. post-MBE iCa: 1.25 [IQR: 1.85-2.24]; p = 0.03). CONCLUSION: MBE efficiently reduces leukocytes and improves oxygenation in severe Bordetella pertussis infection in infants. Careful monitoring of calcium and thrombocytes seems mandatory.

Interference in HbA1c measurement: a case of electropherogram shift due to hyperleukocytosis leading to the discovery of leukemic mantle cell lymphoma.

HbA1c is a pivotal biomarker in diabetes management, reflecting long-term glycaemic control. HbA1c is often measured with capillary electrophoresis, which generally is a very precise technique, but there can be interference, especially in the case of haemoglobin diseases. Thus, in patients with underlying conditions, the accurate measurement of HbA1c can be challenging. We present a case of special interference in a 74-year-old female patient referred to a HbA1c test, in whom the measurement was thought to be significantly affected by hyperleukocytosis and led to an unexpected diagnosis of leukemic low-grade lymphoma. This case report highlights the underrecognized potential interference of leukocytosis in HbA1c measurement. It underscores the importance of clinical vigilance when interpreting HbA1c results in patients with underlying haematological conditions.

[Successful induction therapy for acute myeloid leukemia under management with extracorporeal membrane oxygenation].

A 53-year-old woman presented with shortness of breath and hyperleukocytosis and was admitted to our hospital. Shortly after, she went into cardiopulmonary arrest and was resuscitated. Her white blood cell count was 566,000/µl, with 94.5% cup-like blasts positive for MPO staining and FLT3-ITD positive, so she was diagnosed with acute myeloid leukemia (AML) M1. She also had disseminated intravascular coagulation and tumor lysis syndrome. Extracorporeal membrane oxygenation (ECMO) was started to manage bilateral pulmonary thromboembolism that had developed due to deep vein thrombosis, and induction therapy was performed under ECMO. On the third day of illness, the patient developed cerebral hemorrhage. Hematological remission was confirmed on the 39th day of illness. After consolidation therapy with chemotherapy and an FLT3 inhibitor, she underwent allogeneic hematopoietic stem cell transplantation, and remains alive. Case reports suggest strong evidence of mortality benefit from ECMO in patients with hematologic malignancies, particularly when ECMO served as a bridge through chemotherapy. Our patient suffered from cardiopulmonary arrest due to hyperleukocytosis and pulmonary thromboembolism, but was saved by induction of remission under ECMO. Improvements in supportive care should lead to reduction in early deaths during induction therapy.

Clinical characteristics and outcomes of children with newly diagnosed acute myeloid leukemia and hyperleukocytosis managed with different cytoreductive methods.

BACKGROUND: Hyperleukocytosis in patients with acute myeloid leukemia (AML) has been associated with worse outcomes. For cytoreduction, leukapheresis has been used but its clinical utility is unknown, and low-dose cytarabine (LD-cytarabine) is used as an alternative method. METHODS: Children with newly diagnosed AML treated between 1997 and 2017 in institutional protocols were studied. Hyperleukocytosis was defined as a leukocyte count of ≥100 × 109 /L at diagnosis. Clinical characteristics, early complications, survival data, and effects of cytoreductive methods were reviewed. Among 324 children with newly diagnosed AML, 49 (15.1%) presented with hyperleukocytosis. Initial management of hyperleukocytosis included leukapheresis or exchange transfusion (n = 16, considered as one group), LD-cytarabine (n = 18), hydroxyurea (n = 1), and no leukoreduction (n = 14). RESULTS: Compared with patients who received leukapheresis, the percentage decrease in leukocyte counts following intervention was greater among those who received LD-cytarabine (48% vs. 75%; p = .02), with longer median time from diagnosis to initiation of protocol therapy (28.1 vs. 95.2 hours; p < .001). The incidence of infection was higher in patients (38%) who had leukapheresis than those who receive LD-cytarabine (0%) or leukoreduction with protocol therapy (14%) (p = .008). No differences were noted in the outcomes among the intervention groups. Although patients with hyperleukocytosis had higher incidences of pulmonary and metabolic complications than did those without, no early deaths occurred, and the complete remission, event-free survival, overall survival rates, and outcomes of both groups were similar. CONCLUSION: LD-cytarabine treatment appears to be a safe and effective means of cytoreduction for children with AML and hyperleukocytosis.

Benefits of dexamethasone on early outcomes in patients with acute myeloid leukemia with hyperleukocytosis: a propensity score matched analysis.

Hyperleukocytosis is associated with a significant early mortality rate in patients with acute myeloid leukemia (AML). To date, no controlled trial has ever evaluated a strategy to reduce this risk, and the initial management of these patients remains heterogeneous worldwide. The aim of the present study was to evaluate the influence of a short course of intravenous dexamethasone on the early outcomes of patients with hyperleukocytic AML with white blood cell (WBC) count above 50 × 109/L. Clinical and biological data of all consecutive patients (1997-2017) eligible for intensive chemotherapy from a single center were retrospectively collected. A total of 251 patients with a median age of 51 years and a median WBC count of 120 × 109/L were included, 95 of whom received dexamethasone. Patients treated with dexamethasone had higher WBC count and a more severe disease compared with those who did not, and they presented more often with leukostasis and hypoxemia, resulting in a more frequent need for life-sustaining therapies (p < 0.001). To account for these imbalances, patients were compared after adjusting for a propensity score, which included all variables with a prognostic influence in the overall cohort. In the matched cohort, dexamethasone was associated with lower early death (OR = 0.34, p = 0.0026) and induction failure rate (OR = 0.44, p = 0.02) and better overall survival (HR = 0.60, p = 0.011), with no impact on relapse risk (cHR = 0.73, p = 0.39). The overall survival benefit was confirmed among all tested subgroups. This study suggests that dexamethasone administration is safe and associated with a lower risk of induction mortality in patients with hyperleukocytic AML and deserves prospective evaluation.

Outcome of patients with newly diagnosed AML admitted to the ICU, including preemptive admission - a multi-center study.

Acute myeloid leukemia (AML) can lead to life-threatening complications that may require intensive care unit (ICU) management. It has been advocated that early preemptive (ePE) ICU admission, before the onset of organ failure, could benefit some high-risk patients such as those with hyperleukocytosis. The aim of this study was to retrospectively analyze the outcome of newly diagnosed AML patients who required ICU admission in five academic centers with a special focus on patients with an ePE admission strategy, i.e., those transferred to the ICU without any organ failure (modified SOFA score ≤ 2 [omitting thrombocytopenia] and no life-sustaining intervention in the first 24 h following ICU admission) before the start of induction therapy. Between January 2017 and December 2019, 428 patients were included among which 101 were admitted to the ICU. Among patients requiring life-sustaining interventions (n = 83), 18 (22%) died while in the ICU but ICU survivors had the same survival as those not admitted to the ICU. Patients with an ePE admission (n = 18) had more comorbidities and high-risk disease features such as hyperleukocytosis but required no life-sustaining interventions while in the ICU. In a subgroup analysis of patients with hyperleukocytosis ≥ 50 G/l at diagnosis (n = 85), patients not admitted to the ICU and those admitted with an ePE strategy had similar outcomes. This study provides encouraging results about ICU outcome in AML patients during induction therapy but the potential benefit of an ePE strategy must be confirmed prospectively.

Therapeutic leukocytapheresis for leukostasis in chronic lymphocytic leukemia: A case report and literature review.

Chronic lymphocytic leukemia (CLL) is a clonal mature B-cell neoplasm with a typically indolent clinical course. Though most clinicians follow these neoplasms through observation alone, an aggressive transformation to prolymphocytic leukemia, diffuse large-B-cell lymphoma (Richter transformation) or classical Hodgkin lymphoma requires immediate attention. We present a case of extreme leukocytosis (>1 million/µL) in a previously diagnosed CLL patient. Due to symptomatic leukostasis, she was started on cytoreductive therapies including leukocytapheresis. After three rounds of leukocytapheresis (LCP) and concurrent chemotherapy, her white blood cell count decreased from a maximum 1262 × 103 /µL to 574 × 103 /µL. To our knowledge, CLL with symptomatic leukostasis that required therapeutic LCP is rarely reported in literature. We propose that therapeutic LCP is of value in such rare, yet dangerous settings like our case.

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.

Molecular profiling of patients with cytogenetically normal acute myeloid leukemia and hyperleukocytosis.

BACKGROUND: Acute myeloid leukemia (AML) with initial hyperleukocytosis is associated with high early mortality and a poor prognosis. The aims of this study were to delineate the underlying molecular landscape in the largest cytogenetic risk group, cytogenetically normal acute myeloid leukemia (CN-AML), and to assess the prognostic relevance of recurrent mutations in the context of hyperleukocytosis and clinical risk factors. METHODS: The authors performed a targeted sequencing of 49 recurrently mutated genes in 56 patients with newly diagnosed CN-AML and initial hyperleukocytosis of ≥100 G/L treated in the AMLCG99 study. The median number of mutated genes per patient was 5. The most common mutations occurred in FLT3 (73%), NPM1 (75%), and TET2 (45%). RESULTS: The predominant pathways affected by mutations were signaling (84% of patients), epigenetic modifiers (75% of patients), and nuclear transport (NPM1; 75%) of patients. AML with hyperleukocytosis was enriched for molecular subtypes that negatively affected the prognosis, including a high percentage of patients presenting with co-occurring mutations in signaling and epigenetic modifiers such as FLT3 internal tandem duplications and TET2 mutations. CONCLUSIONS: Despite these unique molecular features, clinical risk factors, including high white blood count, hemoglobin level, and lactate dehydrogenase level at baseline, remained the predictors for overall survival and relapse-free survival in hyperleukocytotic CN-AML.

Lipegfilgrastim may cause hyperleukocytosis.

INTRODUCTION: Granulocyte colony-stimulating factors (G-CSF) are utilized both in the treatment and prophylaxis of chemotherapy-induced neutropenia. Lipegfilgrastim is a long-acting G-CSF. Albeit it provides ease of administration compared to short-acting GCSFs, some lipegfilgrastim-related adverse events may occur. Bone pain, widespread body pain, and feeling of fever are among common adverse effects, while rare but more serious adverse effects such as leukocytosis, spleen rupture, interstitial pneumonia, acute respiratory distress syndrome, capillary leak syndrome, hypokalemia, and glomerulonephritis may occur as well. CASE REPORT: We reported a case of hyperleukocytosis that developed due to prophylactic administration of lipegfilgrastim following the first course of neoadjuvant pertuzumab (840-420 mg), trastuzumab (8-6mg/kg), and docetaxel (75 mg/m2) in a 45-year-old female patient with a diagnosis of breast invasive ductal carcinoma. The patient, who presented with weakness, loss of appetite, and oral intake disorder, had elevated white blood cell (WBC), lactate dehydrogenase (LDH), and uric acid levels in her test results. Peripheral smear (PS) had a left shift. MANAGEMENT AND OUTCOME: Intravenous 0.9% NaCl and peroral allopurinol were started to be administered to the patient. On the ninth day of hospitalization, the patient's clinical manifestation improved, and her WBC, LDH, uric acid, and PS returned to normal. Besides, the progression to tumor lysis syndrome (TLS) was prevented by appropriate hydration and allopurinol treatment. In subsequent chemotherapies (CTs), lipegfilgrastim was discontinued and filgrastim was started. The patient whose hyperleukocytosis did not recur was operated on following neoadjuvant CT. The patient's routine follow-up continues without any problems. DISCUSSION: Although lipegfilgrastim-induced hyperleukocytosis has not been reported in the literature, it should be borne in mind that hyperleukocytosis and related complications may occur, as in our case.

Acute leukemia presenting as acute lower limb ischemia.

Objectives: Acute lower limb ischemia (ALLI) is a common vascular emergency. However, ALLI presenting as the initial symptom of acute leukemia (AL) is scarce. Here we present a case of ALLI in the setting of acute myeloid leukemia (AML) while systematically reviewing the current literature to withdraw conclusions about the management, prognosis, and treatment for this atypical presentation of AL. Methods: We conducted a systematic electronic research according to Preferred Reporting Items for Systematic Review and Meta-Analysis protocol (PRISMA) for articles published from January 1981 up to January 2021 concerning ALLI in the setting of acute leukemia (AL). Patients' baseline characteristics were recorded and nine outcomes of interest were studied. Results: Twenty-six individuals, 16 males with a mean age of 46.3 years (±20) were included in this review. The diagnosis included 13 AML patients (50%), 11 acute promyelotic leukemia (APL) (42.3%) and two acute lymphoblastic leukemias (ALL) (7.7%). Treatment varied among nine different regimens. Four patients were treated with chemotherapy alone (15.4%), four with thrombectomy alone (15.4%), and 11 with a combination of chemotherapy and thrombectomy (42.3%). Eight major amputations were recorded (30. 8%). Thirty-day mortality was 35.7%. Forty-eight peripheral thrombotic events were recorded with 12 patients suffering recurrent thrombotic events. Conclusion: ALLI as the presenting symptom of AL is a rare condition that carries significant mortality and amputation rates. Timely diagnosis is crucial concerning short-term survival and limb salvage. APL, despite being the rarest form of AL, represented a significant proportion of the patient population in this review. The role of leukostasis in the disease's progression and the efficacy of leukapheresis as a treatment regimen should be further investigated through case-control studies.

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.

Analysis of clinical characteristics of severe pertussis in infants and children: a retrospective study.

BACKGROUND: The incidence of pertussis shows an increasing trend in recent years, but some clinicians often lack sufficient understanding of the clinical characteristics and risk factors for severe pertussis, and more effective measures should be taken to reduce the incidence and mortality of pertussis in young infants METHODS: A retrospective study was conducted, and 184 infants and children with pertussis who had been hospitalized in the Department of Pediatrics of Beijing Ditan Hospital affiliated with Capital Medical University from January 2016 to December 2017 were included. Clinical data of the patients were collected and the clinical characteristics were statistically analyzed RESULTS: Among the 184 patients, 41.85% were infants < 3 months of age, and 65.22% of the total patients were not vaccinated against pertussis. There were 22 critically ill children, among whom 4 died, and compared with mild cases, they had a higher proportion of children younger than 3 months of age and infants not vaccinated against pertussis (63.64% vs. 38.89% and 100% vs. 60.49%, respectively); a higher proportion of children with severe pneumonia (100% vs. 0%); higher leukocyte count(× 109/L , 35.80 ± 20.53 vs 19.41 ± 8.59); and a higher proportion of children with severe hyperleukocytosis (18.18% vs. 0%, respectively) (P<0.05) CONCLUSIONS: 1. Infants aged <3 months not vaccinated for pertussis appear more likely to become infected and have more severe disease. 2. Severe pneumonia and hyperleukocytosis are the main mechanisms underlying severe pertussis.

Sudden death due to leukostasis in a subject with undiagnosed chronic lymphocytic leukemia.

Sudden death due to leukostasis and lymphocyte thrombi in patients with chronic hematologic malignancies is rare. Leukostasis is characterized by highly elevated leukemic cell count and decreased tissue perfusion symptoms, leading to severe complications and even death. Chronic lymphocytic leukemia (CLL) is a chronic lymphoproliferative disorder that shows a highly heterogeneous clinical course, ranging from indolent form to very aggressive disease. Due to its low metabolic and mitotic rate, there is a lower incidence of clinically significant leukostasis in patients with CLL. Two main theories have been proposed in the development of leukostasis: (1) increased blood viscosity due to large leukemic cell populations; (2) high metabolic activity and cytokine production by leukemic cells. Both mechanisms lead to local hypoxic damage.We present a case of a 70-year-old man who died suddenly in the absence of symptoms. Autopsy and histology examinations revealed findings consistent with CLL and diffuse leukostasis involving the major organs' vessels.In the presence of gross and/or microscopic findings suggesting a potential hematologic malignancy, undiagnosed or relapsing hematologic malignancies should be considered in the differential diagnosis of sudden deaths.

Therapeutic leukapheresis and thrombapheresis in medical emergencies.

The management of hyperleukocytosis or thrombocytosis by therapeutic cytapheresis in the early 21 st century is far from codified (universal). Therapeutic cytapheresis have been proposed to achieve more rapid cytoreduction in peripheral blood than old universal support in order to quickly prevent potential complications. But, there are no randomized studies demonstrating the superiority of cytapheresis over other treatments alone. In this short review, based on our own experience (since 1980), we will give the indications and the role of cytapheresis procedures and we will try to answer the questions: when is therapeutic cytapheresis appropriate and do they still have a place in 2020, especially as a medical emergency?

Polymorphisms in arsenic (+ 3 oxidation state) methyltransferase (AS3MT) predict the occurrence of hyperleukocytosis and arsenic metabolism in APL patients treated with As2O3.

Polymorphisms in arsenic (+ 3 oxidation state) methyltransferase (AS3MT) have been shown to be related to interindividual variations in arsenic metabolism and to influence adverse health effects in acute promyelocytic leukemia (APL) patients treated with arsenic trioxide (As2O3). The occurrence of hyperleukocytosis with As2O3 treatment seriously affects the early survival rate of APL patients, but no definite explanation for such a complication has been clearly established. To clarify the causes of this situation, AS3MT polymorphisms 14215 (rs3740390), 14458 (rs11191439), 27215 (rs11191446), and 35991 (rs10748835) and profiles of plasma arsenic metabolites were evaluated in a group of 54 newly diagnosed APL patients treated with single-agent As2O3. High-performance liquid chromatography-hydride generation-atomic fluorescence spectrometry (HPLC-HG-AFS) was used to determine the concentrations of plasma arsenic metabolites. Plasma arsenic methylation metabolism capacity was evaluated by the percentage of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), primary methylation index (PMI, MMA/iAs), and secondary methylation index (SMI, DMA/MMA). The results showed that APL patients who developed hyperleukocytosis had a higher plasma iAs%, but a lower MMA% and PMI than those who did not develop hyperleukocytosis during As2O3 treatment. In addition, patients with the AS3MT 14215 (rs3740390) CC genotype had significantly higher plasma iAs% and incidence of hyperleukocytosis, but lower PMI than patients with the CT + TT genotype. Conversely, we did not observe statistically significant associations between the occurrence of hyperleukocytosis and AS3MT 14458 (rs11191439), 27215 (rs11191446), and 35991 (rs10748835) polymorphisms in our study subjects. These results indicated that AS3MT 14215 (rs3740390) might be used as an indicator for predicting the occurrence of hyperleukocytosis in APL patients treated with As2O3.

Early Leukapheresis Depletion in an Ex-Premature with Severe Acute Respiratory Distress Syndrome Due to Bordetella Pertussis and Coronavirus Infection.

We describe a 2 weeks corrected gestational age infant admitted in pediatric intensive care unit (PICU) for severe acute respiratory distress syndrome (ARDS) associated to Bordetella pertussis and Coronavirus infection. He developed leukocytosis as soon as ARDS required intubation and aggressive mechanical ventilation: hence he underwent 3 early therapeutic leukapheresis treatments in order to avoid the worsening of related cardiopulmonary complications, according to recent literature on pertussis infection in infants. The infant was discharged from PICU healthy.

Pre-chemotherapy white blood cell depletion by therapeutic leukocytapheresis in leukemia patients: A single-institution experience.

BACKGROUND: Hyperleukocytosis is commonly seen in acute and chronic leukemias. Therapeutic leukocytapheresis using an automatic cell separator can help to achieve prompt leukoreduction to reduce the rate of thrombotic events and early mortality as well as to prevent tumor lysis syndrome. AIM: In this study, we report a single center's experience in managing leukemia patients with therapeutic leukocytapheresis prior to chemotherapy. MATERIALS AND METHODS: Leukocytapheresis procedures were performed in 192 leukemia patients (including acute myeloid leukemia [AML], acute lymphoblastic leukemia [ALL], and chronic myeloid leukemia [CML]) with hyperleukocytosis between January and December 2016. RESULTS: Median % reduction of white blood cell (WBC) count was 30.5% and median % removal efficiency was 46.7% for 75 procedures where the waste bag was sampled. WBC removal efficiency strongly depended on diagnosis (and was 71%, 66%, and 39% for ALL, AML, and CML, respectively). Procedures were generally well tolerated with only 9 out of 192 patients having mild adverse effects. DISCUSSION AND CONCLUSION: In the absence of specific guidelines for the management of hyperleukocytosis, leukocytapheresis in association with chemotherapy should be considered early in clinical practice.

False-positive blood culture results in patients with hematologic malignancies.

Blood cultures are the most valuable tool when bacteremia is clinically suspected. Technical advances have led to the development of automated blood culture systems to detect bacterial infections. Usually positive signals in automated blood culture systems result from the proliferation of microorganisms. Cases are classified as false-positive when the automated blood culture system produces a positive signal but no microorganisms are detected on Gram-stained smears and no microorganism growth is observed in blood subcultures. False-positive blood culture results are very rare in patients with hematologic malignancies. Recently, we encountered four patients who had false-positive blood culture results. Two of the patients were diagnosed with acute leukemia, involving hyperleukocytosis and an excess of blasts. The other two patients were diagnosed with acute leukemia and diffuse large B cell lymphoma with leukocytopenia. Although hypercapnia or acidosis, apart from hyperleukocytosis, might also cause false-positive results, our cases clearly did not have these conditions. We should be aware of the possibility that false-positive blood culture results can occur in patients with leukocytopenia, as well as hyperleukocytosis. To understand the mechanisms responsible for the observed false-positive results, additional studies are needed after the accumulation of similar cases.