Impact of leukapheresis on early death rate in adult acute myeloid leukemia presenting with hyperleukocytosis

Leukostasis in adult acute hyperleukocytic leukemia: a clinician's digest

Leukostasis is a poorly understood and life-threatening complication of acute hyperleukocytic leukemia. The incidence of hyperleukocytosis and leukostasis differs among various subtypes of leukemias. While the pathophysiology of leukostasis is not fully understood, recent research has elucidated many novel pathways that may have therapeutic implications in the future. Respiratory and neurological compromise represents the classical clinical manifestations of leukostasis. If it is not diagnosed and treated rapidly, the one-week mortality rate is approximately 40%. Targeted induction chemotherapy is an important component of the successful treatment of leukostasis, although other modalities of cytoreduction are being used and investigated. Copyright © 2016 John Wiley & Sons, Ltd.

Early Complications of Hyperleukocytosis and Leukapheresis in Childhood Acute Leukemias

Hyperleukocytosis in children with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with early morbidity and mortality. The benefit from leukapheresis is controversial, and its complications are not well defined. We analyzed the frequency of early complications in children with ALL and AML presenting with white blood cell (WBC) count >100 × 10(9)/L, and the type and frequency of complications related to leukapheresis. During a 12-year period, 84 of 634 (13%) ALL and 18 of 143 (12.5%) AML patients presented with hyperleukocytosis. Leukapheresis was performed in 18 ALL and 12 AML patients. The median initial WBC was 474 × 10(9)/L in the leukapheresis group compared with 175 × 10(9)/L in the nonleukapheresis group. Neurological leukostasis occurred in 6 ALL (7.1%) and 4 AML (22.2%) patients. Pulmonary leukostasis occurred in 16 ALL (19%) and 4 AML patients (22.2%). Neurological symptoms improved in few patients after leukapheresis, except in patients with very high WBC (>650 × 10(9)/L in ALL and >400 × 10(9)/L in AML). Leukapheresis improved respiratory symptoms in some patients but caused worsening symptoms in others. Early death was associated with neurological complications, AML diagnosis, and coagulopathy. Leukapheresis did not delay initiation of chemotherapy, nor did it impact early response to chemotherapy or long-term survival. Complications included femoral vein thrombosis, electrolyte imbalances, and hemodynamic instability, which were all reversible. The role of leukapheresis as a cytoreductive procedure in childhood hyperleukocytic leukemia remains to be well defined.

Pre-treatment with oral hydroxyurea prior to intensive chemotherapy improves early survival of patients with high hyperleukocytosis in acute myeloid leukemia

Acute myeloid leukemia with high white blood cell count (WBC) is a medical emergency. A reduction of tumor burden with hydroxyurea may prevent life-threatening complications induced by straight chemotherapy. To evaluate this strategy, we reviewed medical charts of adult patients admitted to our institution from 1997 to 2011 with non-promyelocytic AML and WBC over 50 G/L. One hundred and sixty patients were included with a median WBC of 120 G/L (range 50-450), 107 patients received hydroxyurea prior to chemotherapy, and 53 received emergency induction chemotherapy (CT). Hospital mortality was lower for patients treated with hydroxyurea (34% versus 19%, p = 0.047) even after adjusting for age (p < 0.01) and initial WBC count (p = 0.02). No evidence of any difference between treatment groups in terms of WBC decline kinetics and disease free survival (p = 0.87) was found. Oral hydroxyurea prior to chemotherapy seems a safe and efficient strategy to reduce early death of hyperleukocytic AML patients.

Initial respiratory status in hyperleukocytic acute myeloid leukemia: prognostic significance and effect of leukapheresis

This study investigated whether initial respiratory status in hyperleukocytic acute myeloid leukemia (AML), as defined by oxygen/ventilatory support, is (1) associated with early mortality and overall survival and (2) improved after leukapheresis. A retrospective chart review of 89 patients requiring leukapheresis was performed. White blood cell count (WBC) decreased from 153 (56-475) × 10(9)/L to 60 (17-259) × 10(9)/L after first leukapheresis (p < 0.01). Initial respiratory status was room air (n = 40), low (n = 31) or high flow oxygen therapy (n = 8) or mechanical ventilation (n = 10). As compared to admission, respiratory status significantly deteriorated after both first and second leukapheresis (p < 0.01) and was not different at day 5 for patients still alive (p = 0.131). Both day 28 mortality and overall survival were significantly affected by initial respiratory status (p < 0.01). Despite being effective in reducing WBC, leukapheresis did not improve respiratory status of hyperleukocytic AML patients, a factor strongly associated with survival.

How Center Volumes Affect Early Outcomes in Acute Myeloid Leukemia

Early mortality (EM) is all too frequent during induction chemotherapy for acute myeloid leukemia. Older patients shoulder an undue amount of this burden as a result of the inherent biology of their disease and increased comorbidities. EM rates in academic centers have seen a sharp decline over the past 20 years; however, data from population-based registries show that EM rates for the general population have significantly lagged behind. In this review, we analyze the data available on EM in academic centers and the general population, explore recent improvements in supportive care and the use of predictive models, and finally investigate the relationship between case volume and complications during chemotherapy.

How I treat hyperleukocytosis in acute myeloid leukemia

Hyperleukocytosis (HL) per se is a laboratory abnormality, commonly defined by a white blood cell count >100 000/µL, caused by leukemic cell proliferation. Not the high blood count itself, but complications such as leukostasis, tumor lysis syndrome, and disseminated intravascular coagulation put the patient at risk and require therapeutic intervention. The risk of complications is higher in acute than in chronic leukemias, and particularly leukostasis occurs more often in acute myeloid leukemia (AML) for several reasons. Only a small proportion of AML patients present with HL, but these patients have a particularly dismal prognosis because of (1) a higher risk of early death resulting from HL complications; and (2) a higher probability of relapse and death in the long run. Whereas initial high blood counts and high lactate dehydrogenase as an indicator for high proliferation are part of prognostic scores guiding risk-adapted consolidation strategies, HL at initial diagnosis must be considered a hematologic emergency and requires rapid action of the admitting physician in order to prevent early death.

Leukocytapheresis for the treatment of hyperleukocytosis secondary to acute leukemia

Patients presenting with new or recurrent acute leukemia, particularly of the myeloid lineage, with WBC counts exceeding 100 × 109/L are often considered for leukocytapheresis, especially if they are experiencing symptoms of leukostasis. These symptoms are thought to occur because of blast aggregates and WBC thrombi in the circulation, which reduce blood flow. Leukostasis may cause various complications, including hyperviscosity syndrome, vascular occlusion resulting in intracranial hemorrhages and respiratory failure, and perivascular leukemic infiltrates. Leukostasis occurs more commonly with a high WBC count and with leukemias of monocytoid lineage such as acute myelomonocytic leukemia, which is a reflection of the nature of the leukemic blasts. Leukocytapheresis is used in an effort to quickly decrease a patient's circulating blast count, which can both prevent the development of leukostasis and provide symptomatic relief of leukostasis. However, the impact of leukocytapheresis on early- and long-term mortality is controversial, with several studies producing conflicting results. In this chapter, the pathophysiology of leukostasis, performance of leukocytapheresis, and efficacy of this treatment are reviewed.

Leukapheresis in management of hyperleukocytosis in children's leukemias

We describe 16 leukapheresis (LK) procedures performed in 7 children with different types of leukemia and hyperleukocytosis. We also provide an analysis of previously published experiences of pediatric LK. Median age and body weight of patients were 12.3 years (range, 0.2 to 16.7 y) and 49 kg (range, 5 to 61 kg). Immediate pre-first-LK median white blood cell count was 478×10/L (108×10/L to 988×10/L). All cytoreduction were performed on Cobe Spectra cell separator. Sixty-eight percent of procedures were performed with peripheral veins. Extracorporeal line had been primed with red blood cell for 31% of LK. The median decrease in white blood cell count after each LK was 33% (0% to 69%), and overall decrease after completion of LK procedures was 62% (11% to 94%). Only minor clinical adverse events and no metabolic complication were attributable to LK. No more clinical symptom of hyperleukocytosis was observed after completion of LK procedures. Our findings are consistent with reported results in other pediatric series: LK is a well-tolerated procedure that can be safely performed with an experienced pediatric team even on the smallest children.

Clinical characteristics and outcomes in patients with acute promyelocytic leukaemia and hyperleucocytosis

The clinical characteristics, treatment options and outcomes in patients with acute promyelocytic leukaemia (APL) and hyperleucocytosis remain poorly defined. This study reviewed 242 consecutive patients with APL; 29 patients (12%) had a white blood cell count (WBC) ≥ 50 × 10(9) /l at presentation (median WBC 85·5 × 10(9) /l). Patients with hyperleucocytosis had inferior complete remission (CR) rates (69% vs. 88%; P = 0·004) and higher 4-week mortality (24% vs. 9%; P = 0·018) compared to patients without hyperleucocytosis. We noted a trend towards inferior 3-year disease-free survival (DFS) (69% vs. 80%; P = 0·057) and inferior 3-year overall survival (OS) (74% vs. 92%; P = 0·2) for patients with hyperleucocytosis. Leukapheresis was performed in 11 (38%) of the 29 patients with hyperleucocytosis. CR rate and 3-year OS were not significantly improved in patients who received leukapheresis. CR rate and 3-year OS for the 15 patients with hyperleucocytosis treated with all-trans retinoic acid (ATRA) plus arsenic trioxide (ATO) plus cytotoxic therapy (idarubicin or gemtuzumab ozogamicin) combinations were 100% and 100% vs. 57% and 35% for the 14 patients treated with non-ATRA/ATO combinations (P = 0·004 and P = 0·002). Leukapheresis does not improve the outcomes in patients with APL presenting with hyperleucocytosis. ATRA/ATO-based combinations are superior to other regimens in these patients.

Therapeutic leukapheresis: 9-year experience in a University Hospital

BACKGROUND

Hyperleucocytosis is associated with higher morbidity and mortality related to possible development of leucostasis, tumour lysis syndrome and/or disseminated intravascular coagulation. There is insufficient evidence of the need for leukocytapheresis during early treatment of hyperleucocytosis, and its efficiency remains controversial, although leucoreduction is a measure that can prevent adverse events and death. The aim of this study was to analyse the safety and effectiveness of therapeutic leukocytapheresis and its influence on early mortality in our case series, adjusted to independent mortality risk factors described in the literature.

MATERIALS AND METHODS

This was a retrospective review (June 2003-June 2012) of procedures carried out for the treatment of hyperleucocytosis at the Haematology and Haemotherapy Service of Miguel Servet University Hospital. The patients' data and technical information were prospectively registered for each leukocytapheresis session.

RESULTS

Thirteen patients underwent a total of 27 leukocytapheresis procedures. After an average of two sessions, a statistically significant drop in the initial leucocyte counts was observed (p<0.01), as well as a relevant drop in lactate dehydrogenase levels. The only analytical value statistically related to early mortality in univariate analysis was initial creatinine level greater than 1.2 mg/dL (p=0.012, OR=2.5).

DISCUSSION

Despite the small size and limited homogeneity of our case series, we can conclude that leukocytapheresis is a safe and effective therapeutic measure for leucoreduction in haematological pathologies of any lineage, particularly in patients without acute myeloid leukaemia. Patients with acute myeloid leukaemia had worse outcomes within 6 months of having finished leukocytapheresis sessions, as well as in terms of mean global survival and mean time of mortality. However, global mortality rates were similar in patients with or without acute myeloid leukaemia.

Leukapheresis in childhood acute leukemias: single-center experience

Hyperleukocytosis in patients with leukemia is associated with early mortality, especially due to the pulmonary and neurological complications of leukostasis. The prompt use of leukapheresis may improve patients' survival in the initial treatment period. The medical records of all previously untreated acute leukemia patients were reviewed to determine whether there was hyperleukocytosis at presentation. This study summarizes a single-center experience of leukapheresis that was applied to 12 children with acute leukemia and hyperleukocytosis. The median leukocyte count at diagnosis was 589,000/mm(3) (range: 389,000-942,000/mm(3)) for ALL patients and 232,000/mm(3) (range: 200,000-282,000/mm(3)) for AML patients. A central venous catheter (CVC) was inserted, and leukapheresis procedures were repeated at 12-hour intervals. A total of 29 leukapheresis cycles were performed on 12 children. The median number of cycles of leukapheresis required by each patient was two (range: 1-4). The median absolute and percentage reductions in white blood cell (WBC) count after the first cycle of leukapheresis were 113,000/mm(3) (range: 55,000-442,000/mm(3)) and 36% (range: 16-57.4%), respectively. As a laboratory finding, mild hypocalcemia was the most frequently observed complication. No patients developed any other problem related to the procedure. Our results showed that leukapheresis is a safe and effective procedure if performed by experienced staff.

The role of therapeutic leukapheresis in hyperleukocytotic AML

PURPOSE

Hyperleukocytosis in AML with leukostasis is a serious life-threatening condition leading to a high early mortality which requires immediate cytoreductive therapy. Therapeutic leukapheresis is currently recommended by the American Society of Apheresis in patients with a WBC>100 G/l with signs of leukostasis, but the role of prophylactic leukapheresis before clinical signs of leukostasis occur is unclear.

PATIENTS

We retrospectively analyzed the role of leukapheresis in 52 patients (median age 60 years) with hyperleukocytotic AML with and without clinical signs of leukostasis. Since leukapheresis was performed more frequently in patients with signs of leukostasis due to the therapeutic policy in our hospital, we developed a risk score for early death within seven days after start of therapy (EDd7) to account for this selection bias and to independently measure the effect of leukapheresis on EDd7.

RESULTS

20 patients received leukapheresis in combination to chemotherapy compared to 32 patients who received chemotherapy only. In a multivariate logistic regression model for the estimation of the probability of EDd7 thromboplastin time and creatinine remained as independent significant parameters and were combined to create an EDd7 risk score. The effect of leukapheresis on EDd7 was evaluated in a bivariate logistic regression together with the risk score. Leukapheresis did not significantly change early mortality in all patients with a WBC≥100 G/l.

DISCUSSION

Prophylactic leukapheresis in hyperleukocytotic patients with and without leukostasis did not improve early mortality in our retrospective study. Larger and prospective clinical trials are needed to validate the risk score and to further explore the role of leukapheresis in AML with hyperleukocytosis.

[Leukostasis and tumor lysis: important complications of hyperleukocytosis]

The occurrence of hyperleukocytosis (leukocytes > 100.000/μl) is associated with complications such as leukostasis, tumor lysis and consumption coagulopathy in patients with acute leukemia much more often than in patients with chronic malignant hematological diseases. To manage these situations may be complex as organ failure is often imminent or manifest, infectious complications arise and indications for induction chemotherapy are usually urgent. Prophylaxis and therapy of the tumor lysis syndrome consists of hydration, lowering of uric acid and the management of electrolyte disturbances. Leukostasis requires immediate reduction of the leukocyte count by leukapheresis, administration of hydroxycarbamide and, ultimately, by causative and specific treatment of the underlying disease itself. In patients with curable diseases or favorable long-term prognosis, transfer to the intensive care unit must be evaluated early in the course of impending organ dysfunction, especially in cases of acute respiratory failure.

Childhood acute lymphoblastic leukemia with hyperleukocytosis at presentation

Background

Hyperleukocytosis caused by acute lymphoblastic leukemia (ALL) is associated with early morbidity and mortality due to hyperviscosity arising from the excessive number of leukocytes.This study was designed to assess the incidence of hyperleukocytosis, survival outcomes, and adverse features among pediatric ALL patients with hyperleukocytosis.

Methods

Between January 2001 and December 2010, 104 children with previously untreated ALL were enrolled at the Pusan National University Hospital. All of them were initially stratified based on the National Cancer Institute (NCI) risk; 48 (46.2%) were diagnosed with high-risk ALL. The medical charts of these patients were retrospectively reviewed.

Results

Twenty (19.2%) of the 104 children with ALL had initial leukocyte counts of >100×10⁹/L, and 11 patients had a leukocyte count of >200×10⁹/L. Male gender, T-cell phenotype, and massive splenomegaly were positively associated with hyperleukocytosis. Common early complications during induction therapy included renal dysfunction, and central nervous system hemorrhage. The complete remission (CR) rate for the pediatric ALL patients with hyperleukocytosis (94.1%) was similar to the overall CR rate (95.6%). The estimated 3-year event free survival (EFS) and overall survival of ALL children with hyperleukocytosis were 75.0% and 81.2%, respectively. However, patients with initial leukocyte counts >200×10⁹/L had a lower EFS than those with initial leukocyte counts 100-200×10⁹/L (63.6% vs. 100%; P=0.046).

Conclusion

The outcome of pediatric ALL cases with an initial leukocyte count >200×10⁹/L was very poor, probably due to early toxicity-related death during induction therapy.

Minimally early morbidity in children with acute myeloid leukemia and hyperleukocytosis treated with prompt chemotherapy without leukapheresis

BACKGROUND/PURPOSE

Patients with acute myeloid leukemia (AML) and hyperleukocytosis, defined as an initial white blood cell (WBC) count of ≥ 100 × 10(9)/L, are often treated with leukapheresis. In this study, we have reported our experience of treating AML without leukapheresis.

METHODS

From November 1, 1995, to May 31, 2012, there were 74 children (≤18 years old) with de novo AML other than acute promyelocytic leukemia. Seventeen patients had an initial WBC count ≥ 100 × 10(9)/L. Prompt chemotherapy was started within hours whereas leukapheresis was not performed.

RESULTS

The median age of the 17 patients with hyperleukocytosis was 7.4 years (range: 0-16 years), and the median initial WBC count was 177 × 10(9)/L (range: 117-635 × 10(9)/L). The median time between admission and initiation of chemotherapy was 4.5 hours (range: 2-72 hours) in patients with hyperleukocytosis, whereas it was 13 hours (range: 2-120 hours) in those without hyperleukocytosis. Seven patients (7/17, 41%) had one or more early complications before or during the first 2 weeks of chemotherapy. Fifteen of the 16 patients who received prompt chemotherapy achieved complete remission (93.8%), comparable with those without hyperleukocytosis (98.2%; p = 0.33).

CONCLUSION

Children with AML and hyperleukocytosis, treated with prompt chemotherapy without leukapheresis, had minimal early morbidities.

Leukapheresis and low-dose chemotherapy do not reduce early mortality in acute myeloid leukemia hyperleukocytosis: a systematic review and meta-analysis

The role of leukapheresis and low-dose chemotherapy is unclear in decreasing early mortality in acute myeloid leukemia (AML) patients with hyperleukocytosis. This systematic review was conducted to describe early mortality (deaths during first induction) in patients with AML with an initial white blood count≥100×10(9)L(-1) stratified by the approach to leukapheresis and hydroxyurea/low-dose chemotherapy. Twenty-one studies were included. Weighted mean early deaths rate (20 studies, 1354 patients) was 20.1% (95% confidence interval 15.0-25.1). Neither leukapheresis strategy (p=0.67) nor hydroxyurea/low-dose chemotherapy (p=0.23) influenced the early death rate. Early mortality related to hyperleukocytosis in AML is not influenced by universal or selected use of leukapheresis or hydroxyurea/low-dose chemotherapy.

Cranial irradiation in adults diagnosed with acute myelogenous leukemia presenting with hyperleukocytosis and neurologic dysfunction

This study describes our institution's experience using whole brain radiation therapy (WBRT) to treat patients with acute myelogenous leukemia (AML) presenting with hyperleukocytosis. After approval by the institutional review board, we identified patients with AML and hyperleukocytosis using hospital records. The primary endpoints in the study included alleviation of neurological symptoms (or prevention if prophylactic RT was used), overall survival, development of intracranial hemorrhage (ICH) and ≥ grade 3 toxicities using the Common Terminology Criteria for Adverse Events version 4.0 (CTCAE v4.0). Eighteen patients received WBRT for the treatment of AML hyperleukocytosis. Thirteen patients received treatment in order to control neurological symptoms. Clinical assessment showed that 12 of 13 patients (92%) achieved resolution of neurological symptoms either concurrent with RT or immediately after RT. The mean overall survival for all of the patients who received WBRT was 14.2 months (95% confidence interval, 5.4-23.0). No patient who received RT experienced ≥ grade 3 toxicity. Two (6%) patients developed ICH following therapy. Our institution's experience demonstrates that WBRT may be utilized as part of multimodality therapy in order to alleviate or prevent neurological symptoms in patients with AML presenting with leukostasis.

The effect of volume replacement during therapeutic leukapheresis on white blood cell reduction in patients with extreme leukocytosis

BACKGROUND

Extreme leukocytosis, generally defined as a white blood cell (WBC) count of more than 100 × 10(9) /L consisting largely of blast cells, especially when accompanied by clinical signs and symptoms of leukostasis or hyperviscosity, often predicts a poor clinical outcome in patients with acute leukemia. In this study, we aimed to investigate the effect of volume replacement (VR) during therapeutic leukapheresis (TA) procedure on early mortality rate and WBC reduction.

STUDY DESIGN AND METHODS

We retrospectively analyzed 29 patients who underwent TA from 2007 to 2011. Fifteen of the patients underwent TA procedure with VR and 14 of the patients underwent TA procedure without VR.

RESULTS

WBC reduction was significantly higher in patients who underwent TA with VR (p < 0.001). Early mortality rate was significantly lower in leukemia patients who underwent TA with VR than in patients who underwent TA without VR (p < 0.01); early mortality rates were 6.7% for 7-day and 13.8% for 100-day survivals. The mortality rates in the TA without VR group, however, were 42.9 and 71.4% for 7- and 100-day survivals, respectively.

CONCLUSION

Decreased early mortality rate in TA with VR group may be associated with prompt reduction of WBCs achieved with TA with VR and may also be associated with removal of the cytokines related to leukostasis. TA with VR would give more time for induction chemotherapy and increased overall survival rate.

Exchange transfusion as a life-saving intervention in three patients with different haematological malignancies with severe hyperleukocytosis where leukapheresis was not available

Hyperleukocytosis is a rare but potentially serious complication of haematological malignancies. It is usually treated with rehydration, prevention of tumour lysis syndrome and the administration of cytotoxic therapy. Leukapheresis may be life-saving in emergency cases. In this article we describe how, in a resource-limited setting where leukapheresis was not available, manual exchange transfusion was utilised as a life-saving intervention in three patients with different haematological malignancies complicated by hyperleukocytosis. Further we outline the procedure that was carried out and evaluated possible complications associated with this rarely used practice.

Hyperleukocytosis and leukocytapheresis in acute leukaemias: experience from a single centre and review of the literature of leukocytapheresis in acute myeloid leukaemia

BACKGROUND

Hyperleukocytosis is usually defined as leukocyte count >100 × 10(9)  L(-1) and can be seen in newly diagnosed leukaemias. Hyperleukocytic leukaemia is associated with a risk of organ failure and early death secondary to leukostasis. Mechanical removal of leukocytes by the apheresis technique, leukocytapheresis, is a therapeutic option in these patients.

METHODS

During a 16-year period, 16 patients were treated with leukocytapheresis (35 apheresis procedures) for hyperleukocytosis/leukostasis. We present our experience, and in addition we review previous studies of hyperleukocytosis/leukocytapheresis in patients with acute myeloid leukaemia (AML).

RESULTS

We used a highly standardised approach for leukocytapheresis in leukaemia patients with hyperleukocytosis. The average leukocytapheresis number for each patient was 2·2 (range 1-6). Median leukocyte count before apheresis was 309 × 10(9)  L(-1) (range 104-935); the mean leukocyte count reduction was 71%, corresponding to a mean absolute reduction of 219 × 10(9)  L(-1). No serious side effects were seen during or immediately after apheresis.

CONCLUSIONS

The data suggest that our standardised technique for leukocytapheresis effectively reduced the peripheral blood leukaemia cell counts. Previous studies in AML also support the conclusion that this is a safe and effective procedure for the treatment of a potentially life-threatening complication, but apheresis should always be combined with early chemotherapy.

WITHDRAWN: Exchange transfusion as a life-saving intervention in three patients with different haematological malignancies with severe hyperleukocytosis where leukapheresis was not available

The Publisher regrets that this article is an accidental duplication of an article that has already been published, 10.1016/j.transci.2013.09.003. The duplicate article has therefore been withdrawn.

Leucodepletion for hyperleucocytosis--first report on a novel technology featuring electronic interphase management

BACKGROUND AND OBJECTIVES

Therapeutic leucodepletion plays an established role in the initial treatment of patients with acute myeloid leukaemia (AML) and possibly other leukaemias presenting with leucostasis. Recently, a new leucodepletion technology, Spectra Optia IDL, has become available that differs from its predecessor, COBE Spectra MNC, by a variety of electronic supports, including by electronic adjustment of buffy coat positioning at the collection port. Given the paucity of patients in need of leucodepletions and marked differences in clinical presentation as well as blast properties (e.g. size, density), formal clinical trials comparing leucodepletion technologies have never been executed.

MATERIALS AND METHODS

Here, we present aggregate data from eight leucodepletions performed in AML patients with clinical signs of leucostasis between 11/2011 and 07/2012 with the new device and compare the apheresis outcomes with those from fifteen leucodepletions performed with the old technology between 06/2010 and 10/2011.

RESULTS

Patients did not differ with respect to epidemiological data. Pre-apheresis leucocyte count (WBC) was significantly higher in Spectra Optia IDL patients. Tolerability was excellent with both devices. Basic apheresis denominators such as duration, processed volume, inlet pump rate, ACD-A consumption and product volume were very similar. A negative correlation between pre-apheresis WBC and collection efficiency was noted. Mean collection efficiency for leucocytes with Spectra Optia IDL (47·3%) was similar to that with COBE Spectra MNC (50·5%). Platelet attrition was similar with both devices, approximately 30%.

CONCLUSION

The novel, electronically guided leukapheresis system is suitable for leucodepletion.

The need for continuing chemotherapy for leukemic cell lysis pneumopathy in patients with acute myelomonocytic/monocytic leukemia

Although fatal pulmonary complications frequently occur during the course of acute leukemia, a minor proportion of the complications are due to leukemia itself. Infections, drug reactions and concomitant medical conditions are the major causes of respiratory distress in leukemic patients. We treated four patients with acute myeloid leukemia complicated by leukemic cell lysis pneumopathy (LCLP). All of the patients had leukemia of monocytoid origin and their respiratory function deteriorated soon after chemotherapy initiation. Although two of the patients required mechanical ventilation, all four improved after continued chemotherapy. Our experience indicates that, in cases of LCLP, chemotherapy should be continued with maximal respiratory support.

Leukocyte Depletion by Therapeutic Leukocytapheresis in Patients with Leukemia

Hyperleukocytosis is a complication of various leukemias and can result in life-threatening leukostasis. Critical white blood cell (WBC) counts are conventionally defined as higher than 100 × 10(9)/l in acute myeloid leukemia and > 300 × 10(9)/l in acute lymphatic leukemia and other leukemic disorders (e. g. chronic myeloid leukemia). Leukocytapheresis is a therapeutic tool to reduce leukocyte counts in patients with symptomatic or threatening leukostasis until induction chemotherapy works. In patients with temporary contraindications against cytotoxic drugs, e.g. during pregnancy, leukocytapheresis can be used as a bridging therapy until conventional chemotherapy can be started. Therapeutic leukocytapheresis should be performed in specialized centers by experienced, well-trained staff. Thorough monitoring of the patients is extremely relevant. During a single procedure, WBC count can be reduced by 10-70%. Treatment should be repeated daily and can be discontinued when the symptoms of leukostasis have been resolved and/or leukocyte counts have fallen below the critical thresholds. There are no prospective studies evaluating the clinical efficacy of therapeutic leukocytapheresis in patients with hyperleukocytosis. It can be concluded from retrospective studies that leukocytapheresis might have some beneficial effect in early morbidity and mortality of patients with newly diagnosed AML but has no influence on overall long-term survival. Induction chemotherapy is the most important treatment in these patients and must never be postponed.

Hyperleukocytosis, leukostasis and leukapheresis: practice management

Hyperleukocytosis, arbitrarily defined in acute leukemia as a white blood cell count greater than 100,000/mL, often is associated with increased morbidity and mortality in patients with leukemic processes. It can induce leukostasis, tumor lysis syndrome and disseminated intravascular coagulopathy and has significant prognostic implications with or without one of these clinical complications. The main sites that tend to be injured from the obstructions are the central nerve system and lungs. Despite characteristic clinical presentations, the diagnosis of leukostasis is rarely made with high confidence. The main goal of the management of hyperleukocytosis and/or leukostasis is to reduce the white blood cell count before starting induction chemotherapy. The cytoreduction can be achieved by either leukapheresis and/or hyroxyurea. The technical aspects, complications and efficacy of leukapheresis are discussed in the current article.

Conventional apheresis therapies: a review

This article reviews advances in the scientific basis and medical practice of plasmapheresis and cytapheresis therapies. Newly-characterized autoantibodies in neuromyelitis optica, Guillain-Barre variants, anti-neutrophil cytoplasmic antibody (ANCA) vasculitides, etc., exemplify the modern molecular biology which now provides a rigorous framework of understanding for the clinical practice of plasmapheresis. Clinical trials continue to clarify the appropriate use of therapeutic plasmapheresis (TPE) in these and other diseases. Centrifugal (cTPE) and membrane filtration (mTPE) types of plasmapheresis are compared, with details of the plasmapheresis prescription, anticoagulation choices, replacement fluids and other practical considerations. Plasma removal is more efficient with cTPE; mTPE systems have a lower plasma extraction ratio, and therefore require higher blood flow rates or longer procedure times. Autoantibodies and other pathogenic macromolecules targeted for removal by plasmapheresis can be depleted predictably when the plasma is discarded, as in conventional TPE. On-line plasma processing to regenerate the patient's own plasma avoids the need for replacement albumin solutions or plasma transfusion, but is inherently less efficient at removing the target molecule, so usually requires a longer procedure. Therapeutic white cell reduction (leukapheresis), platelet reduction (thrombocytapheresis) and red cell exchange (erythrocytapheresis) require centrifugal apheresis systems.

Guidelines on the use of therapeutic apheresis in clinical practice--evidence-based approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence-based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence-based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed.

Myeloproliferative disorders and the hyperviscosity syndrome

Myeloproliferative disorders and the serum hyperviscosity syndrome can rapidly manifest with emergent presentations. Hyperviscosity occurs from pathologic elevations of either the cellular or acellular (protein) fractions of the circulating blood. Classic hyperviscosity syndrome presents with the triad of bleeding diathesis, visual disturbances, and focal neurologic signs. Emergency medicine providers should be aware of these conditions and be prepared to rapidly initiate supportive and early definitive management, including plasma exchange and apharesis. Early consultation with a hematologist is essential to managing these complex patients.

Diagnosis and management of acute myeloid leukemia in adults: recommendations from an international expert panel, on behalf of the European LeukemiaNet

In 2003, an international working group last reported on recommendations for diagnosis, response assessment, and treatment outcomes in acute myeloid leukemia (AML). Since that time, considerable progress has been made in elucidating the molecular pathogenesis of the disease that has resulted in the identification of new diagnostic and prognostic markers. Furthermore, therapies are now being developed that target disease-associated molecular defects. Recent developments prompted an international expert panel to provide updated evidence- and expert opinion–based recommendations for the diagnosis and management of AML, that contain both minimal requirements for general practice as well as standards for clinical trials. A new standardized reporting system for correlation of cytogenetic and molecular genetic data with clinical data is proposed.

Conservative management of priapism secondary to leukemia

We report four cases of leukemia (three chronic myeloid and one T-cell acute lymphoblastic) presenting with priapism in children 9- to 13-year old. All of them presented with hyperleukocytosis, and three had anemia plus thrombocytosis. All patients underwent chemotherapy and two had leukopheresis. In all cases, priapism was managed conservatively. Erection required up to 13 days to start improving but none of the patients developed clinical evidence of long-term erectile dysfunction. Based on these cases, conservative management of priapism in children with leukemia might be adequate and not lead to long-term erectile dysfunction.