An Analysis of the Worldwide Utilization of Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia

Acute myeloid leukemia (AML) has an aggressive course and a historically dismal prognosis. For many patients, hematopoietic stem cell transplantation (HSCT) represents the best option for cure, but access, utilization, and health inequities on a global scale remain poorly elucidated. We wanted to describe patterns of global HSCT use in AML for a better understanding of global access, practices, and unmet needs internationally. Estimates of AML incident cases in 2016 were obtained from the Global Burden of Disease 2019 study. HSCT activities were collected from 2009 to 2016 by the Worldwide Network for Blood and Marrow Transplantation through its member organizations. The primary endpoint was global and regional use (number of HSCT) and utilization of HSCT (number of HSCT/number of incident cases) for AML. Secondary outcomes included trends from 2009 to 2016 in donor type, stem cell source, and remission status at time of HSCT. Global AML incidence has steadily increased, from 102,000 (95% uncertainty interval: 90,200-108,000) in 2009 to 118,000 (104,000-126,000) in 2016 (16.2%). Over the same period, a 54.9% increase from 9659 to 14,965 HSCT/yr was observed globally, driven by an increase in allogeneic (64.9%) with a reduction in autologous (-34.9%) HSCT. Although the highest numbers of HSCT continue to be performed in high-resource regions, the largest increases were seen in resource-constrained regions (94.6% in Africa/East Mediterranean Region [AFR/EMR]; 34.7% in America-Nord Region [AMR-N]). HSCT utilization was skewed toward high-resource regions (in 2016: AMR-N 18.4%, Europe [EUR] 17.9%, South-East Asia/Western Pacific Region [SEAR/WPR] 11.7%, America-South Region [AMR-S] 4.5%, and AFR/EMR 2.8%). For patients <70 years of age, this difference in utilization was widened; AMR-N had the highest allogeneic utilization rate, increasing from 2009 to 2016 (30.6% to 39.9%) with continued low utilization observed in AFR/EMR (1.7% to 2.9%) and AMR-S (3.5% to 5.4%). Across all regions, total HSCT for AML in first complete remission (CR1) increased (from 44.1% to 59.0%). Patterns of donor stem cell source from related versus unrelated donors varied widely by geographic region. SEAR/WPR had a 130.2% increase in related donors from 2009 to 2016, and >95% HSCT donors in AFR/EMR were related; in comparison, AMR-N and EUR have a predilection for unrelated HSCT. Globally, the allogeneic HSCT stem cell source was predominantly peripheral blood (69.7% of total HSCT in 2009 increased to 78.6% in 2016). Autologous HSCT decreased in all regions from 2009 to 2016 except in SEAR/WPR (18.9%). HSCT remains a central curative treatment modality in AML. Allogeneic HSCT for AML is rising globally, but there are marked variations in regional utilization and practices, including types of graft source. Resource-constrained regions have the largest growth in HSCT use, but utilization rates remain low, with a predilection for familial-related donor sources and are typically offered in CR1. Further studies are necessary to elucidate the reasons, including economic factors, to understand and address these health inequalities and improve discrepancies in use of HSCT as a potentially curative treatment globally.

[Disseminated infection by Mycobacterium scrofulaceum: apropos of 3 cases]

BACKGROUND

Mycobacterium avium-M. Intracellulare complex and Mycobacterium kansasii cause most of nontuberculous mycobacteria infections in AIDS patients in Spain. Mycobacterium scrofulaceum is rarely isolated as a cause of disseminated disease and most of case have been reported before the AIDS occurrence.

METHODS

Three clinical cases of patients with disseminated disease caused by M.scrofulaceum and AIDS are reviewed.

RESULTS

Clinical presentation in all cases was similar to those of other disseminated mycobacterial infection, and was also linked to severe immunosuppression (CD4 cell count < 100 CD4/mm3).

CONCLUSIONS

In our area, M. scrofulaceum is the second species of nontuberculous mycobacteria causing disseminated disease in AIDS patients. The most frequent species is M. avium-M. intracellulare complex. For diagnosis an AIDS patient complaining of febrile syndrome without foci and severe immunosuppression, is mandatory to obtain blood cultures and biopsy or adenopathy aspirates if present. To our knowledge, these are the first reports in our country.

Intestinal permeability to 51Cr-EDTA and orocecal transit time in cystic fibrosis

Intestinal permeability was investigated in 16 children with cystic fibrosis and 14 age-matched controls, making use of 51Cr-EDTA as probe molecule. Orocecal transit time was also evaluated using the lactulose/hydrogen breath test. There was an increase in permeability to 51Cr-EDTA in patients with cystic fibrosis (mean 13.62%) compared with the control group (mean 1.08%). The orocecal transit time was prolonged in patients with cystic fibrosis compared with controls. Mean fasting breath hydrogen concentration was significantly greater in cystic fibrosis patients (13 ppm) compared with control patients (3 ppm). There was no correlation between the percentage of 51Cr-EDTA excreted and the orocecal transit time in either control or cystic fibrosis patients.

Could CAPD modulate the hemodynamic changes induced by rHuEPO treatment?

Hemodynamic response to treatment with erythropoietin has been analyzed on two different groups of patients. The first group of 25 patients was treated with hemodialysis. The second group of 27 was treated with peritoneal dialysis. Both groups were studied before starting the treatment with erythropoietin, after reaching the hemoglobin target point, and after one year of treatment. The following parameters were recorded: basal and hemoglobin target point, time and dosage of response, incidence of arterial hypertension, diastolic and systolic left ventricular diameters, interventricular septum and posterior wall thickness, ejection fraction, fractional fiber shortening, left ventricular mass index, cardiac output index and peripheral resistance index. The incidence of hypertension was 28.8% and, in both techniques, stabilization of left ventricular mass index occurred a year later. When the hemoglobin target point was reached, a decrease in cardiac output and an increase in peripheral resistance was found. These changes were more evident in the group of patients treated with HD. After a year of treatment, both peripheral resistance and cardiac output were similar to basal values in both groups of patients.

Peritoneal dialysis efficiency in CAPD patients in treatment with rHuEPO

Possible modifications in peritoneal behaviour that can be caused by erythropoietin (EPO) treatment and/or correction of anemia in the ultrafiltration and peritoneal diffusion were studied in 24 CAPD patients. The evolution of the patients on the medium run was also studied. The dialysate to plasma ratio, the peritoneal clearance and the mass transfer coefficient of urea and creatinine and the ultrafiltration volume were studied, baseline, after reaching the hemoglobin target, and after eight months of treatment. The group of patients developed a decrease in the dialysate to plasma ratio and in the peritoneal clearance of creatinine. After evaluating the effects of the hemoglobin and the hematocrit, we found a decrease in the dialysate to plasma ratio of urea and creatinine, and in the peritoneal clearance of creatinine. A decrease was also found in the mass transfer coefficients of urea and creatinine. An increase in the ultrafiltration was also found in the patients with hemoglobin levels higher or equal to 11 g/dl. Those changes are reversible after turning the hemoglobin levels back to levels lower than 11 g/dl.

Effect of recombinant human erythropoietin treatment on hemodynamic parameters in continuous ambulatory peritoneal dialysis and hemodialysis patients

We studied the hemodynamic changes and the incidence of hypertension after correction of anemia with recombinant human erythropoietin (rhEPO) in 25 hemodialysis (HD) and in 27 continuous ambulatory peritoneal dialysis (CAPD) patients with a mean age of 44.6 years and a mean time on dialysis of 43.6 months. We analyzed basal and final hemoglobin concentrations, time elapsed to reach target hemoglobin, rhEPO dosage, and the following echocardiographic parameters: left ventricular end-systolic and end-diastolic diameters and volumes, posterior wall thickness, interventricular septum, ejection fraction, fractional fiber shortening, cardiac output index, and peripheral vascular resistance index. We did not find any significant difference between HD and CAPD patients in basal and final hemoglobin, concentrations, time elapsed to reach target hemoglobin, dose of rhEPO received for response, and incidence of hypertension. Changes were more evident in HD patients, with a decrease of 15% in cardiac output index and an equal increase of peripheral vascular resistance,. In the patients on CAPD, these variations were less important, with a decrease in cardiac output index of 10% and no significant change in peripheral vascular resistance. Despite both techniques showing the occurrence of hypertension, the left ventricular mass stabilized during the study time. We conclude that CAPD seems to modulate the changes observed in hemodynamic parameters after rhEPO treatment.