Thalassemia-free and graft-versus-host-free survival: outcomes of hematopoietic stem cell transplantation for thalassemia major, Turkish experience.

We report the national data on the outcomes of hematopoietic stem cell transplantation (HSCT) for thalassemia major (TM) patients in Turkey on behalf of the Turkish Pediatric Stem Cell Transplantation Group. We retrospectively enrolled 1469 patients with TM who underwent their first HSCT between 1988 and 2020 in 25 pediatric centers in Turkey. The median follow-up duration and transplant ages were 62 months and 7 years, respectively; 113 patients had chronic graft versus host disease (cGVHD) and the cGVHD rate was 8.3% in surviving patients. Upon the last visit, 30 patients still had cGvHD (2.2%). The 5-year overall survival (OS), thalassemia-free survival (TFS) and thalassemia-GVHD-free survival (TGFS) rates were 92.3%, 82.1%, and 80.8%, respectively. cGVHD incidence was significantly lower in the mixed chimerism (MC) group compared to the complete chimerism (CC) group (p < 0.001). In survival analysis, OS, TFS, and TGFS rates were significantly higher for transplants after 2010. TFS and TGFS rates were better for patients under 7 years and at centers that had performed over 100 thalassemia transplants. Transplants from matched unrelated donors had significantly higher TFS rates. We recommend HSCT before 7 years old in thalassemia patients who have a matched donor for improved outcomes.

Nosocomial pneumonia caused by water-born Legionella pneumophila in a pediatric hematopoietic stem cell transplantation recipient for thalassemia major.

BACKGROUND: Nosocomial pneumonia caused by Legionella pneumophila serogroup 2-14 occurred in a 7-year-old patient following allogeneic hematopoietic stem cell transplantation for thalassemia major. CASE: The patient was diagnosed with nosocomial Legionella pneumophila by polymerase chain reaction (PCR) examination of the bronchoalveolar lavage and culturing Legionella pneumophila serogroup 2-14 from the patient`s room faucet water. Legionella pneumophila was eradicated from our hospital`s water distribution system by superheating and chemical eradication methods (hyper-chlorination and hydrogen peroxide). We did not detect any other case after this event. CONCLUSION: Early recognition of contamination of the hospital water system with Legionella proves the importance of prevention in new cases.

Risks and outcomes of invasive fungal infections in pediatric allogeneic hematopoietic stem cell transplant recipients receiving fluconazole prophylaxis: a multicenter cohort study by the Turkish Pediatric Bone Marrow Transplantation Study Group.

Invasive fungal infections (IFIs) are a major cause of infection-related morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Data from pediatric settings are scarce. To determine the incidence, risk factors and outcomes of IFIs in a 180-day period post-transplantation, 408 pediatric patients who underwent allogeneic HSCT were retrospectively analyzed. The study included only proven and probable IFIs. The cumulative incidences of IFI were 2.7%, 5.0%, and 6.5% at 30, 100, and 180 days post-transplantation, respectively. According to the multivariate analysis, the factors associated with increased IFI risk in the 180-day period post-HSCT were previous HSCT history (hazard ratio [HR], 4.57; 95% confidence interval [CI] 1.42-14.71; P = .011), use of anti-thymocyte globulin (ATG) (HR, 2.94; 95% CI 1.27-6.80; P = .012), grade III-IV acute graft-versus-host-disease (GVHD) (HR, 2.91; 95% CI 1.24-6.80; P = .014) and late or no lymphocyte engraftment (HR, 2.71; 95% CI 1.30-5.62; P = .007). CMV reactivation was marginally associated with an increased risk of IFI development (HR, 1.91; 95% CI 0.97-3.74; P = .063). IFI-related mortality was 1.5%, and case fatality rate was 27.0%.The close monitoring of IFIs in pediatric patients with severe acute GVHD who receive ATG during conditioning is critical to reduce morbidity and mortality after allogeneic HSCT, particularly among those with prior HSCT and no or late lymphocyte engraftment.

Prognostic impact of RUNX1 and ETV6 gene copy number on pediatric B-cell precursor acute lymphoblastic leukemia with or without hyperdiploidy.

The ETV6/RUNX1 fusion gene is a valuable prognostic marker that is frequently observed in B-cell precursor acute lymphoblastic leukemia (B-cell ALL). However, the clinical significance of copy number aberrations in these genes remains unclear. In this study, the effects of various aberrations inETV6 and RUNX1 gene copy number on disease prognosis were evaluated in 21 pediatric patients diagnosed with B-cell ALL with/without t(12;21). The prognostic significance of changes in gene copy number of ETV6 or RUNX1 in the presence or absence of hyperdiploidy, trisomy 21, and t(12;21) translocation were also evaluated. RUNX1 gene copy number amplifications were detected in 83 % of the patients who lacked t(12;21) and in all of the patients with hyperdiploidy. Trisomy 21 was detected in 78 % of the patients with hyperdiploidy. Changes in ETV6 gene copy number were detected in patients who lacked both the t(12;21) translocation and RUNX1 gene copy number amplifications. However, RUNX1 gene copy number amplification and ETV6 deletion were observed in all of the patients with t(12;21). RUNX1 gene copy number amplification was associated with hyperdiploidy, but not with t(12;21). Thus, the evaluation of distinct FISH and cytogenetic patterns in patients with B-cell ALL may strengthen the prognostic significance of changes in gene copy number.

The impact of donor age and sex on the nucleated cell count and CD34 count in healthy bone marrow donors.

BM remains an important source of stem cells. The BM characteristics change with age but the estimation of CD34 calculation of one CD34+ cell per 100 nucleated cells is used for all donors including pediatric donors in the operating room before getting the actual CD34 count. In order to see whether this formula is applicable for pediatric donors, we designed a retrospective study to see the affect of the age and sex on the BM NCC, CD34 count, and CD34/NCC ratios. Ninety-eight BM collections from 91 related donors were evaluated retrospectively (median age: nine yr [1.5-54 yr]; M/F: 41/50). A significant negative correlation was found between the donor age and NCC (r = -0.229, p < 0.05), CD34 count (r = -0.563, p < 0.01), and CD34/NCC (r = -0.664, p < 0.01). The negative correlation for CD34 count and CD34/NCC persisted in female and male donor groups. When donors younger than 16 yr of age were compared with the older donor group, the median NCC, median CD34 count, and CD34/NCC were significantly lower in the older group (p < 0.01). Age and sex have to be taken into consideration to avoid unnecessary high-volume collections and increased operating room time in the younger donors.

Primary adrenal insufficiency in a child after busulfan and cyclophosphamide-based conditioning for hematopoietic stem cell transplantation.

High rates of skeletal complications, growth disturbances, thyroid and gonadal dysfunction have been described in children undergoing stem cell transplantation. Although secondary adrenal insufficiency has been diagnosed, no primary adrenal insufficiency has been reported after busulfan and cyclophosphamide (Bu/Cy)-based conditioning regimens for stem cell transplantation in children. A 9-year-old girl with myelodysplastic syndrome was treated with stem cell transplantation of allogeneic origin. She received myeloablative conditioning chemotherapy, Bu and Cy. Her serum cortisol level was normal before stem cell transplantation. Then, 17 months after stem cell transplantation, chronic graft-versus-host disease developed and was treated with methyl prednisolone for 3 months. The control endocrinological investigation revealed low serum cortisol and high serum adrenocorticotropin (ACTH) levels 6 months after completion of methyl prednisolone treatment. The ACTH stimulation test demonstrated primary adrenal insufficiency, and the other etiologies of primary adrenal insufficiency were excluded. The patient received oral prednisolone replacement therapy. She was followed-up for 44 months and required increases in steroid doses during stress periods. Primary adrenal insufficiency which was observed in our patient after Bu/Cy-based conditioning regimen for stem cell transplantation has not been reported in children and adrenal function should be closely monitored in these patients both before stem cell transplantation and after stem cell transplantation.

Hemophagocytic lymphohistiocytosis associated with 2009 pandemic influenza A (H1N1) virus infection.

Hemophagocytic lymphohistiocytosis (HLH) has not been described earlier in the context of 2009 pandemic influenza A (H1N1) virus infection, although certain populations are thought to be at risk for complicated pandemic influenza A disease. Here, we report the second case of HLH after infection with the influenza A H1N1 virus treated with peroral oseltamivir successfully.

Relation of soluble endothelial protein C receptor and cytokines after allogeneic hematopoietic stem cell transplantation.

AIM: The objective of this study was to elucidate the effects of tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), interleukin 2 (IL-2), interleukin 6 (IL-6), and interleukin 8 (IL-8) on the expression of soluble endothelial protein C receptor (sEPCR) in the pathogenesis of thrombotic complications after hematopoietic stem cell transplantation (HSCT). METHODS: The relationship between plasma concentrations of proinflammatory cytokines (TNF-α, IL-1ß, IL-2, IL-6, and IL-8) and sEPCR was evaluated in 32 consecutive allogeneic hematopoietic stem cell-transplanted patients prior to conditioning regimen and randomly once between +5 and +30 days after transplantation and compared these results with 20 healthy controls. RESULTS: Soluble endothelial protein C receptor levels did not indicate any significant difference between pre- and posttransplantation period, and sEPCR levels showed a significantly negative correlation between IL-6 and IL-8 (sEPCR and IL-6, r = -.43, P < .01; sEPCR and IL-8, r = -.57, P < .01). There was no correlation between sEPCR levels and TNF-α, IL-1ß, or IL-2 (sEPCR and TNF-α, r = -.13, P > .05; sEPCR and IL-1ß, r = -.1, P ≥ .05; sEPCR and IL-2, r = -.07, P > .05). CONCLUSIONS: Our results suggest that the production of sEPCR was not affected by allogeneic HSCT. Soluble endothelial protein C receptor did not show any positive correlation between these proinflammatory cytokines (TNF-α, IL-1ß, IL-2, IL-6, and IL-8), on the contrary a significantly negative correlation was determined between sEPCR and either IL-6 or IL-8. This negative correlation may be a protective mechanism in the pathway of protein C activation.

Prospective evaluation of acute and chronic renal function in children following matched related donor hematopoietic stem cell transplantation.

Acute and chronic renal impairment are important complications after HSCT. A prospective study was conducted to investigate the glomerular renal function in children who received allogeneic HSCT from matched related donors. Non-radiation conditioning regimens were used in all but one patient. CrCl and serial measurements of serum creatinine were evaluated prior to HSCT, within the first 100 days and one yr after. AKI was defined as at least a 1.5-fold rise in pre-HSCT serum creatinine within the first 100 days and classified as grade 1 to 3 according to the new definition criteria proposed by "AKI Network." Fifty-seven patients were enrolled in the study and 24 patients (42%) had AKI. CsA, amphotericin B, and SOS were found as risk factors for AKI. One yr after HSCT five patients (10%) had CKD and none of them required dialysis. None of the parameters were found as a predictor for CKD. We conclude that AKI is an important complication of HSCT. Careful monitoring of renal function, minimizing the use of nephrotoxic medication, prophylaxis, and effective treatment of SOS might be effective preventive measures to decrease the incidence of AKI.