Pretransplant iron overload may be associated with increased risk of invasive fungal pneumonia (IFP) in patients that underwent allogeneic hematopoietic stem cell transplantation (alloHSCT)

The impact of pretransplant serum ferritin on haploidentical hematopoietic stem cell transplant for acquired severe aplastic anemia in children and adolescents

Haploidentical hematopoietic stem cell transplant (haplo-HSCT) provides an important alternative for children and adolescents with acquired severe aplastic anemia (SAA) lacking matched donors. To test whether pretransplant serum ferritin (SF) represents a candidate predictor for survival and a potential biomarker for graft-versus-host disease (GvHD) in pediatric haplo-HSCT, we retrospectively evaluated 147 eligible patients with SAA who underwent haplo-HSCT. The patients were divided into the low-SF group (< 1000 ng/mL) and the high-SF group (≥ 1000 ng/mL). We found that SF ≥1000 ng/mL independently increased the risk of grade II-IV aGvHD (HR = 2.596; 95% CI, 1.304-5.167, P = 0.007) and grade III-IV aGvHD (HR = 3.350; 95% CI, 1.162-9.658, P = 0.025). Similar probabilities of transplant-related mortality at 100 days were observed in the two groups (6.19 ± 2.45% vs 8.00 ± 3.84%, P = 0.168). The two-year overall survival (85.29 ± 3.89% vs 92.00% ± 3.84%, P = 0.746) and failure-free survival (83.23% ± 4.08% vs 83.37% ± 6.27%, P = 0.915) were comparable. GvHD-/failure-free survival were 60.06 ± 5.10% and 75.56 ± 6.87%, respectively (P = 0.056). In conclusion, elevated pretransplant SF level is associated with higher incidences of grade II-IV aGvHD and grade III-IV aGvHD. However, it is not associated with worse survival after haplo-HSCT for children and adolescent patients with SAA.

Smoking as a Risk Factor of Invasive Fungal Disease: Systematic Review and Meta-Analysis

To investigate the association between smoking and invasive fungal disease (IFD), we searched MEDLINE and Web of Science for studies published until September 2018. Two authors independently performed study selection and data extraction. Relative risks (RRs) were pooled using random-effects meta-analysis. We included 25 studies (18 171 participants; 2527 IFD cases). The meta-analysis showed an increased risk of IFD in smokers (RR 1.41 [95% confidence interval 1.09-1.81]; P = .008). The risk of IFD was higher in retrospective than in prospective studies (RR 1.93 [1.28-2.92] vs. 1.02 [0.78-1.34]; P = .04), in studies with multivariate adjustment compared to studies with univariate analysis (RR 2.15 [1.27-3.64] vs. 1.15 [0.88-1.51]; P = .06), and in studies published after 2002 (RR 2.08 [1.37-3.15] vs. 0.95 [0.75-1.22]; P = .008); other subgroup characteristics did not significantly influence the association in metaregression. Smoking cessation strategies should be implemented, especially in patients who are already at risk for IFD.

Iron overload in the HCT patient: a review

Iron overload (IO) is common in hematologic malignancies and hemoglobinopathies, largely due to red cell transfusion burden. End-organ damage from IO occurs via reactive oxygen species-mediated pathways. The impact of pretransplant IO on hematopoietic cell transplant (HCT) morbidity and mortality remains contentious; studies have shown mixed results, possibly due to variability in study population and design, as well as markers of IO. Ferritin has served as a traditional circulating marker of total body IO, but liver iron content by MRI appears to be a better marker of end-organ involvement. Novel surrogate markers including hepcidin, marrow Prussian blue staining, and labile plasma iron levels may prove to be more specific for HCT complications. Posttransplant phlebotomy, chelation, or both in combination remains the mainstays of treatment, though may ultimately be supplanted by pretransplant or peri-transplant use of bone marrow maturation agents or targeted chelation at time of highest IO risk. This review discusses the pathophysiology of IO in hematologic disease, the evidence supporting and refuting its negative impact on HCT outcomes, as well as current and future therapies.

The Clinical Significance of Iron Overload and Iron Metabolism in Myelodysplastic Syndrome and Acute Myeloid Leukemia

Myelodysplasticsyndrome (MDS) and acute myeloid leukemia (AML) are clonal hematopoietic stem cell diseases leading to an insufficient formation of functional blood cells. Disease-immanent factors as insufficient erythropoiesis and treatment-related factors as recurrent treatment with red blood cell transfusions frequently lead to systemic iron overload in MDS and AML patients. In addition, alterations of function and expression of proteins associated with iron metabolism are increasingly recognized to be pathogenetic factors and potential vulnerabilities of these diseases. Iron is known to be involved in multiple intracellular and extracellular processes. It is essential for cell metabolism as well as for cell proliferation and closely linked to the formation of reactive oxygen species. Therefore, iron can influence the course of clonal myeloid disorders, the leukemic environment and the occurrence as well as the defense of infections. Imbalances of iron homeostasis may induce cell death of normal but also of malignant cells. New potential treatment strategies utilizing the importance of the iron homeostasis include iron chelation, modulation of proteins involved in iron metabolism, induction of leukemic cell death via ferroptosis and exploitation of iron proteins for the delivery of antileukemic drugs. Here, we provide an overview of some of the latest findings about the function, the prognostic impact and potential treatment strategies of iron in patients with MDS and AML.

Retrospective Evaluation of Relationship Between Iron Overload and Transplantation Complications in Pediatric Patient Who Underwent Allogeneic Stem Cell Transplantation Due to Acute Leukemia and Myelodysplastic Syndrome

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) is a curative therapy option for hematologic malignancies. Iron overload is common in this patient group and can impact short-term and long-term nonrelapse mortality.

STUDY DESIGN

Retrospective observational cohort study.

AIMS

To evaluate the effect of iron load on early and late HSCT outcomes in patients with acute leukemia and myelodysplasia to assess the necessity of reducing iron load.

PATIENTS AND METHODS

Sixty patients who underwent HSCT in pediatric stem cell transplantation unit between 2000 and 2012 were evaluated retrospectively. The patients were divided into those with pretransplantation serum ferritin levels above and below the median value of 1299 ng/mL.

RESULTS

Forty-two (70%) of the patients were male, mean ages of the low and high ferritin groups were 85.43±9.42 and 118.56±10.04 months, respectively. Acute graft-versus-host disease (GVHD) within the first 100 days and acute liver GVHD were significantly more common in the high ferritin group (P<0.011 for both). Ferritin level was not associated with rates of engraftment syndrome, veno-occlusive disease, early/late infection, relapse, or overall and disease-free survival.

CONCLUSIONS

In our study, significant result especially in terms of acute liver GVHD, was important to emphasize the need to be more careful in terms of acute liver GVHD risk in early liver pathologies in patients with high levels of ferritin after transplantation. In future large studies may be helpful to explain the relationship between acute liver GVHD and high ferritin levels.

Bone marrow iron score as an indicator for secondary iron overload in acute myeloid leukemia patients

OBJECTIVES

Secondary iron overload due to red blood cell transfusions (RBCT) is associated with increased morbidity and mortality. However, attention for secondary iron overload and its side effects in patients with hematological malignancies may need improvement. The aim of this study was to determine the number of transfused RBCT needed to reach a maximum bone marrow iron score (BMIS).

METHODS

Bone marrow iron score was independently assessed by two researchers on consecutive bone marrow samples of 35 acute myeloid leukemia (AML) patients. The slides were blinded to both researchers to prevent bias. A Kaplan-Meier survival analysis was performed for estimation of the proportion of patients reaching a maximum BMIS.

RESULTS

In total, 141 bone marrow specimens from 35 patients were included. The median number of RBCT to reach a maximum was 20 units (range 6-42, IQR 15-26), after a mean of 1.64 chemotherapy courses (SD 0.99).

CONCLUSIONS

In conclusion, the cumulative RBCT number is associated with BMIS. Due to the considerable variation in number of RBCT to reach a maximum BMIS, BMIS instead of only considering the cumulative RBCT number may be a valuable indicator of secondary iron overload in AML patients. BMIS could guide iron-lowering therapy and/or transfusion strategies in an early stage.

Pharmacometabolomics for predicting variable busulfan exposure in paediatric haematopoietic stem cell transplantation patients

Owing to its narrow therapeutic range and high pharmacokinetic variability, optimal dosing for busulfan is important to minimise overexposure-related systemic toxicity and underexposure-related graft failure. Using global metabolomics, we investigated biomarkers for predicting busulfan exposure. We analysed urine samples obtained before busulfan administration from 59 paediatric patients divided into 3 groups classified by area under the busulfan concentration-time curve (AUC), i.e., low-, medium-, and high-AUC groups. In the high-AUC group, deferoxamine metabolites were detected. Phenylacetylglutamine and two acylcarnitines were significantly lower in the high-AUC group than in the low-AUC group. Deferoxamine, an iron-chelating agent that lowers serum ferritin levels, was detected in the high-AUC group, indicating that those patients had high ferritin levels. Therefore, in a retrospective study of 130 paediatric patients, we confirmed our hypothesis that busulfan clearance (dose/AUC) and serum ferritin level has a negative correlation (r = −0.205, P = 0.019). Ferritin, acylcarnitine, and phenylacetylglutamine are associated with liver damage, including free radical formation, deregulation of hepatic mitochondrial β-oxidation, and hyperammonaemia. Our findings reveal potential biomarkers predictive of busulfan exposure and suggest that liver function may affect busulfan exposure.

Current Review of Iron Overload and Related Complications in Hematopoietic Stem Cell Transplantation

Iron overload is an adverse prognostic factor for patients undergoing hematopoietic stem cell transplantation (HSCT). In the HSCT setting, pretransplant and early posttransplant ferritin and transferrin saturation were found to be highly elevated due to high transfusion requirements. In addition to that, post-HSCT iron overload was shown to be related to infections, hepatic sinusoidal obstruction syndrome, mucositis, liver dysfunction, and acute graft-versus-host disease. Hyperferritinemia causes decreased survival rates in both pre- and posttransplant settings. Serum ferritin levels, magnetic resonance imaging, and liver biopsy are diagnostic tools for iron overload. Organ dysfunction due to iron overload may cause high mortality rates and therefore sufficient iron chelation therapy is recommended in this setting. In this review the management of iron overload in adult HSCT is discussed.

Increased Bone Marrow Iron Scores Are Strongly Correlated With Elevated Serum Ferritin Levels and Poorer Survival in Patients With Iron Overload That Underwent Allogeneic Hematopoietic Stem Cell Transplantation: A Single Center Experience

BACKGROUND

Iron overload is one of the most significant problems as a leading cause of death in patients with leukemia and those who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT).

METHODS

In the current study, we retrospectively evaluated the bone marrow iron scores (BMIS) in patients who underwent alloHSCT (n = 125). The first available bone marrow biopsy specimens prior to the alloHSCT procedure or date of hospitalization (control group) were assessed in a blinded fashion using a standardized scoring system.

RESULTS

A total of 125 patients were enrolled in the study. Seventy-six (60.8%) of the patients were male, and 49 (39.2%) were female. The median level of pre-transplant serum ferritin was 1023.00 ng/mL (range, 393.80-1627.50 ng/mL). The majority of the patients were diagnosed with acute leukemia (83; 66.4%) and lymphomas (20; 16.0%). The median time for neutrophil engraftment was 14.00 days (range, 13.00-16.00 days) and 11.00 days (range, 10.00-14.00 days) for platelet engraftment. The peri-transplant mortality was similar to international mortality rates (3; 2.4%). The overall survival and disease-free survival were strongly correlated with the degree of BMIS, and both were significantly poorer in patients with high bone marrow iron content (P < .001 and P = .012, respectively).

CONCLUSION

The validation of BMIS for risk stratification in patients who undergo alloHSCT may predict posttransplant outcomes.

Risk stratification for invasive fungal infections in patients with hematological malignancies: SEIFEM recommendations

Invasive fungal infections (IFIs) are an important cause of morbidity and mortality in immunocompromised patients. Patients with hematological malignancies undergoing conventional chemotherapy, autologous or allogeneic hematopoietic stem cell transplantation are considered at high risk, and Aspergillus spp. represents the most frequently isolated micro-organisms. In the last years, attention has also been focused on other rare molds (e.g., Zygomycetes, Fusarium spp.) responsible for devastating clinical manifestations. The extensive use of antifungal prophylaxis has reduced the infections from yeasts (e.g., candidemia) even though they are still associated with high mortality rates. This paper analyzes concurrent multiple predisposing factors that could favor the onset of fungal infections. Although neutropenia is common to almost all hematologic patients, other factors play a key role in specific patients, in particular in patients with AML or allogeneic HSCT recipients. Defining those patients at higher risk of IFIs may help to design the most appropriate diagnostic work-up and antifungal strategy.

Major Pulmonary Complications After Hematopoietic Stem Cell Transplant

Both autologous and allogeneic hematopoietic stem cell transplants are important therapeutic options for several benign and malignant disorders. Pulmonary complications, although they have become less frequent, remain a significant cause of morbidity and mortality after hematopoietic stem cell transplant. These complications range from bacterial, fungal, and viral pulmonary infections to noninfectious conditions such as diffuse alveolar hemorrhage and idiopathic pneumonia syndrome. Bronchiolitis obliterans syndrome is the primary chronic pulmonary complication, and treatment of this condition remains challenging. This report highlights the advances in the diagnosis and management of the major pulmonary complications after hematopoietic stem cell transplant. It also underscores the need for prospective and multicenter research to have a better understanding of the mechanisms behind these complications and to obtain more effective diagnostic tool and therapeutic options.