Rasburicase causing severe oxidative hemolysis and methemoglobinemia in a patient with previously unrecognized glucose-6-phosphate dehydrogenase deficiency

Rasburicase is frequently used in tumor lysis syndrome (TLS). Although it is very well tolerated, it can cause severe oxidative hemolytic anemia and methemoglobinemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. We report another case of rasburicase-induced methemoglobinemia in a patient with previously unrecognized G6PD deficiency and review the cases of methemoglobinemia and oxidative hemolysis reported in the literature to date. Patients from ethnicities in which G6PD deficiency is prevalent at high risk of TLS should be screened for G6PD deficiency prior to administration of rasburicase where practical. Asymptomatic decrease in oxygen saturation by oximetry and cyanosis are signs of methemoglobinemia; patients recover with conservative measures including supplemental oxygen and packed red cell transfusion.

Bortezomib with high dose melphalan conditioning for autologous transplant is safe and effective in patients with heavily pretreated and high risk multiple myeloma

There are no uniform guidelines for the treatment of relapsed refractory multiple myeloma (MM), however autologous stem cell transplant (SCT) remains an important treatment modality. Although a number of modifications to high dose melphalan (HDM) conditioning have been evaluated, improvement in overall survival has not been demonstrated. We now report our experience of 23 patients with heavily pretreated MM (median lines of prior treatment 3 [range 1-6]) who underwent SCT with bortezomib and high dose melphalan (BorHDM). The overall response rate (at least partial response [PR]) was 65.4%. Median overall survival (OS) was 24 months. A subset of patients who relapsed ≤ 12 months after initial SCT had significantly longer OS after BorHDM SCT compared to a historical control group who received HDM conditioning alone (14.5 vs. 8 months, respectively, p = 0.011). In summary, BorHDM SCT produces very good response rates in heavily pretreated MM, and may increase survival in the salvage setting in patients who relapse early after initial SCT. We propose that its use should be explored as part of a tandem approach in patients undergoing initial SCT who are at high risk of early relapse.

A risk-adapted protocol for delayed administration of filgrastim after high-dose chemotherapy and autologous stem cell transplantation

INTRODUCTION

The routine use of recombinant human granulocyte-colony stimulating factor (rhG-CSF) after high-dose chemotherapy and autologous stem cell transplantation (auto-SCT) is associated with increased costs. We prospectively explored a strategy that used prophylactic delayed filgrastim only in patients with risk factors.

PATIENTS AND METHODS

This sequential cohort analysis compared the outcomes of consecutive patients, treated on the risk-adapted protocol (RAP) (risk factors: prior febrile neutropenia; age >60 years; and CD34+ cell infused dose of <2 × 10(6/)/kg), who received filgrastim from day +6 after auto-SCT with a historical cohort (historical day-1 cohort [HD1]), who received filgrastim from day +1.

RESULTS

Eighty-two patients were treated in the RAP cohort and compared with 115 patients in the HD1 cohort. There were no differences in median age (55 years) or median CD34+ cell dose (5.21 × 10(6)/kg [range, 2-62.2 × 10(6)/kg] vs. 5.24 × 10(6)/kg [range, 2.4-29.8 × 10(6)/kg]). Filgrastim was used for 6 fewer days in the RAP cohort (median 5 days [range, 0-11 days] vs. 11 days [range, 9-47 days]). There was a small absolute but significant difference in median time to neutrophil recovery in the HD1 cohort for the whole group, 10 days (range, 8-46 days) vs. 11 days (range, 9-22 days) (P = .03) and in patients with myeloma; 10 days (range, 9-14 days) vs. 11 days (range, 9-18 days) (P < .0001) as compared to the RAP cohort. There was no difference in median inpatient duration, 13 days (range, 10-26 days) vs. 12 days (range, 1-38 days) (P = .22) and 3-year survival (79% vs. 83% [P = .43]) between HD1 and RAP cohorts respectively.

CONCLUSIONS

The use of a RAP to identify patients likely to benefit from prophylactic filgrastim is safe and results in cost savings. Patients with myeloma benefit from earlier introduction of filgrastim in terms of neutrophil recovery; this disease-specific observation is an important consideration for future studies.

Rationale for the clinical application of flow cytometry in patients with myelodysplastic syndromes: position paper of an International Consortium and the European LeukemiaNet Working Group

An international working group within the European LeukemiaNet gathered, aiming to determine the role of flow cytometry (FC) in myelodysplastic syndromes (MDS). It was agreed that FC has a substantial application in disease characterization, diagnosis and prognosis. FC may also be useful in predicting treatment responses and monitoring novel and standard therapeutic regimens. In this article the rationale is discussed that flow cytometry should be integrated as a part of diagnostic and prognostic scoring systems in MDS.

Standardization of flow cytometry in myelodysplastic syndromes: a report from an international consortium and the European LeukemiaNet Working Group

Flow cytometry (FC) is increasingly recognized as an important tool in the diagnosis and prognosis of myelodysplastic syndromes (MDS). However, validation of current assays and agreement upon the techniques are prerequisites for its widespread acceptance and application in clinical practice. Therefore, a working group was initiated (Amsterdam, 2008) to discuss and propose standards for FC in MDS. In 2009 and 2010, representatives from 23, mainly European, institutes participated in the second and third European LeukemiaNet (ELN) MDS workshops. In the present report, minimal requirements to analyze dysplasia are refined. The proposed core markers should enable a categorization of FC results in cytopenic patients as 'normal', 'suggestive of', or 'diagnostic of' MDS. An FC report should include a description of validated FC abnormalities such as aberrant marker expression on myeloid progenitors and, furthermore, dysgranulopoiesis and/or dysmonocytopoiesis, if at least two abnormalities are evidenced. The working group is dedicated to initiate further studies to establish robust diagnostic and prognostic FC panels in MDS. An ultimate goal is to refine and improve diagnosis and prognostic scoring systems. Finally, the working group stresses that FC should be part of an integrated diagnosis rather than a separate technique.

Use of empiric antimicrobial therapy in neutropenic fever. Australian Consensus Guidelines 2011 Steering Committee

Administration of empiric antimicrobial therapy is standard practice in the management of neutropenic fever, but there remains considerable debate about the selection of an optimal regimen. In view of emerging evidence regarding efficacy and toxicity differences between empiric treatment regimens, and strong evidence of heterogeneity in clinical practice, the current guidelines were developed to provide Australian clinicians with comprehensive guidance for selecting an appropriate empiric strategy in the setting of neutropenic fever. Beta-lactam monotherapy is presented as the treatment of choice for all clinically stable patients while early treatment with combination antibiotic therapy is considered for patients at higher risk. Due consideration is given to the appropriate use of glycopeptides in this setting. Several clinical caveats, accounting for institution- and patient-specific risk factors, are provided to help guide the judicious use of the agents described. Detailed recommendations are also provided regarding time to first dose, timing of blood cultures, selection of a first-line antibiotic regimen, subsequent modification of antibiotic choice and cessation of therapy.

Premature cardiovascular disease in chronic renal failure

There is a remarkable lack of reliable information about the determinants of risk of cardiovascular disease (CVD) among patients with chronic renal failure. Indeed, such patients have often been deliberately excluded from randomised trials of treatments of CVD, perhaps because of concerns about drug safety. But the absolute risk of CVD among them may be large, so the potential absolute benefits of treatments may also be large, and may well exceed any increased hazards. Hence, as well as further investigation of the underlying mechanisms of cardiac disease, it would be helpful to have some large-scale randomised trials in a wide range of renal patients of interventions (such as cholesterol-lowering drugs, antihypertensives, aspirin, B-vitamins, and antioxidant vitamins) that are of proven or suspected benefit in other settings. If safe and effective treatments can be identified, and started early in the natural history of renal failure, the exceptionally high risk of CVD experienced by these patients could be decreased before and after end-stage renal failure has occurred.