Analysis of BK Virus Infection in Children After Hematopoietic Cell Transplantation: A Retrospective Single-center Study.

BACKGROUND: BK virus (BKV) is one of the most common causes of hemorrhagic cystitis (HC) in children undergoing hematopoietic stem cell transplantation (HSCT). Viruses can be found in urine and serum of immunocompromised patients. OBJECTIVE: This study aimed to evaluate the incidence, clinical course, and risk factors for BKV infection in children undergoing HSCT. METHODS: Retrospectively analyzed children who underwent HSCT at Beijing Children's Hospital, Capital Medical University from June 2020 to June 2022. Data related to the clinical manifestations, engraftment, and prognosis were extracted from medical records. Patients were divided into the case group and the control group, according to the BKV infection or not after HSCT. RESULTS: A total of 149 patients were enrolled in this study, and 61 (40.9%) patients developed BKV infection after HSCT. Among the 61 patients, BKV load was detected in all patients in urine samples and 22 patients in blood samples. The median value of BKV DNA copies in urine and plasma were 9.50×10 7 (5.37×10 2 to 6.84×10 9 ) copies/mL and 2.97×10 3 (9.96×10 2 to 3.58×10 8 ) copies/mL, respectively. The median time from beginning of the conditioning regimen to BKV infection was 23 (0 to 273) days, and the first positive time of urinary BKV was earlier than that of blood (13.5 d [0.0 to 123.0 d] vs. 30.5 d [7.0 to 165.0 d], P =0.003). Among the patients with BKV infection, 36 (59.0%) patients met the diagnosis of hemorrhagic cystitis (HC), and the incidence was higher than that in the control group ( P <0.001). Similarly, 15 (24.6%) patients developed renal function damage in the case group and the proportion was higher than that in the control group. The median follow-up was 5.67 (0.03 to 24.90) months, and there was no significant difference in 1-year overall survival rate between the case group and the control group (84.2%±5.7% vs. 95.3%±2.3%, P =0.688), but the incidence of TA-TMA/VOD (31.1%) and diffuse alveolar hemorrhage (9.8%) in the case group was higher than that in the control group ( P =0.002 and 0.038, respectively). Multivariate analysis showed that age above 5 years old (OR=9.039, 95% CI: 3.561-24.333, P <0.001) and use of MMF (OR=2.708, 95% CI: 1.041-7.044, P <0.05) were independent risk factors for BKV infection after HSCT. CONCLUSION: Among children after HSCT, the incidence of BKV infection was high and BKV infection was associated with an increased incidence of TA-TMA/VOD and diffuse alveolar hemorrhage. Patients older than 5 years of age at the time of HSCT and treated with MMF were more likely to develop BKV infection.

A Case of Female X-linked Chronic Granulomatous Disease Caused by X Chromosome Inactivation Treated with Hematopoietic Stem Cell Transplantation and Literature Review.

Objective: X-linked chronic granulomatous disease (X-CGD) is a rare primary immunodeficiency disease characterized by phagocyte dysfunction. It is caused by genetic mutations in the CYBB gene, predominantly affecting males. However, a small number of female carriers can also present with the disease due to biased X chromosome inactivation.1 This study aims to enhance the understanding of X-CGD in a rare case of an infant and young woman and provide insights into its diagnosis and treatment. Methodology: This study utilized various methods to investigate X-CGD in children and their parents. These methods included assessing neutrophil respiratory burst function, measuring gp91phox protein expression, analyzing chronic granuloma enzyme levels, conducting whole exon gene analysis, and evaluating X chromosome inactivation. Additionally, hematopoietic stem cell transplantation was performed using haploidentical donors from immediate family members. Results: The children in this study were found to be carriers of the CYBB gene mutation, and their neutrophil respiratory burst function was abnormal with no expression of the gp91phox protein. X chromosome inactivation analysis revealed a rate of 99.5%. Following hematopoietic stem cell transplantation, there was successful engraftment of granulocytes and megakaryocytes, with normalization of gene and enzyme examinations. Conclusion: The findings of this study highlight the importance of considering X-CGD in the diagnosis of children and women presenting with granulomatous disease. Furthermore, the use of hematopoietic stem cell transplantation was shown to achieve significant therapeutic effects in the treatment of X-CGD. Further research is warranted to explore early diagnostic strategies for X-CGD and to optimize the use of hematopoietic stem cell transplantation in managing the disease. Early diagnosis and intervention can lead to improved outcomes for patients with X-CGD. This study contributes to the understanding of X-CGD and its treatment by demonstrating the possibility of X-CGD in female carriers and the efficacy of hematopoietic stem cell transplantation. These findings emphasize the importance of early diagnosis and highlight the potential for successful outcomes in the management of X-CGD.

Improved outcomes using unmanipulated haploidentical hematopoietic stem cells combined with third-party umbilical cord blood transplantation for non-malignant diseases in children: The experience of a single center.

BACKGROUND: Unmanipulated haploid HSCT for SAA has resulted in improved outcomes over recent years. However, studies related to unmanipulated haploid HSCs combined with tp-UCB transplantation for other types of NMD are rare. Accordingly, we present the outcomes of 109 pediatric patients with life-threatening NMD undergoing unmanipulated haploid HSCs combined with tp-UCB transplantation. PROCEDURE: We retrospectively investigated 109 pediatric patients with life-threatening NMD treated with unmanipulated haploid HSCs combined with tp-UCB transplantation in a single center. RESULTS: The median days of neutrophil and platelet engraftment were +13 and +22 days, respectively. None of the cases experienced PGF. The incidence rates for grade I-II, III-IV aGVHD and cGVHD were 44.9%, 24.8%, and 9.3%, respectively. The incidence rates of CMV and EBV viremia were 46.7% and 39.4%, respectively. The median follow-up duration was 997 days. In total, 106 patients survived, including 104 cases with FFS and 2 cases with SGF. Three patients died. The 5-year TRM, OS, and FFS were 2.8%, 97.2%, and 96.2%, respectively. CONCLUSION: The results of unmanipulated haploid HSCs combined with tp-UCB in pediatric patients with life-threatening NMD were promising. However, further research is now needed to determine specific factors that might influence the engraftment of HSCs.

[A clinical study of haploid hematopoietic stem cells combined with third-party umbilical cord blood transplantation in the treatment of chronic granulomatous disease].

OBJECTIVE: To investigate the clinical efficacy of haploid hematopoietic stem cells (haplo-HSC) combined with third-party umbilical cord blood (tpCB) transplantation in the treatment of X-linked chronic granulomatous disease (X-CGD). METHODS: The clinical data of 26 boys with X-CGD were retrospectively analyzed who were admitted to the Sixth Medical Center of PLA General Hospital between April 2014 and March 2018. All the patients were treated with haplo-HSC combined with tpCB transplantation. The median age of the patients was 3.5 years. The donor was the father in 25 cases and an aunt in 1 case. Transplantation was 5/6 HLA-matched in 9 cases, 4/6 in 12 cases, and 3/6 in 5 cases. The patients received busulfan, cyclophosphamide, fludarabine, or anti-thymocyte globulin for myeloablative preconditioning. Cyclosporine A and mycophenolate mofetil were used for prevention of acute graft-versus-host disease (aGVHD). Then the patients were treated with haploid bone marrow hematopoietic stem cells combined with tpCB transplantation on day 1 and haploid peripheral hematopoietic stem cells on day 2. The counts of median donor total nucleated cells, CD34+ cells, and CD3+ cells were 14.6×108/kg, 5.86×106/kg, and 2.13×108/kg respectively. RESULTS: The median time to neutrophil and platelet engraftment was 12 and 23 days after transplantation respectively. Full donor hematopoietic chimerism was observed on day 30. Twenty-five cases were from haplo-HSC and 1 was from cord blood. No primary implant failure and implant dysfunction occurred, and secondary implant failure occurred in one case. The NADPH oxidase activity returned to normal one month after transplantation. The incidence of grade I-II aGVHD and grade III-IV aGVHD was 35% and 15% respectively. Chronic GVHD (cGVHD) of the skin occurred in one case, and no progression was observed after steroid administration. During the follow-up period of 6-51 months, 25 patients survived, of whom 24 were disease-free (23 patients without cGVHD and 1 with cGVHD of the skin) and NADPH oxidase activity returned to normal; one patient developed secondary implant failure but survived; one patient died of viral interstitial pneumonia 16 months after transplantation. The 5-year event-free survival rate and overall survival rate were 81%±12% and 89%±10% respectively. CONCLUSIONS: Haplo-HSC combined with tpCB transplantation is one of the effective methods for the treatment of X-CGD in children.

Pediatric acute myeloid leukemia patients with KMT2A rearrangements: a single-center retrospective study.

PURPOSE: Pediatric acute myeloid leukemia (AML) with KMT2A rearrangements has a very different prognosis. Poor outcomes cannot be avoided even after hematopoietic stem cell transplantation. In order to investigate the prognosis and efficacy, we conducted a retrospective analysis. PATIENTS AND METHODS: We retrospectively analyzed a total of 32 children with KMT2A rearrangements AML treated in our hospital between January 2015 and February 2021. RESULTS: The proportion of patients with KMT2A-rearranged in the medium-risk group of overall survival (OS) and event-free survival (EFS) was 100%. No differences in OS, EFS and cumulative incidence of relapse (CIR) were detected between the haploidentical hematopoietic stem cell transplantation (haplo-HSCT) and full matched HSCT (P = 0.289, P = 0.303, P = 0.303). Acute graft-versus-host disease (aGVHD) was often detected in the haplo-HSCT cohort, while full matched HSCT had no obvious aGVHD, assessed as≤1 grade (P < 0.05). Patients in the medium-risk pediatric group could acquire 100% OS and EFS only after chemotherapy. There was no significant difference in OS, EFS and CIR between full matched HSCT and haploidentical transplantation in pediatric AML with KMT2A rearrangements, but full matched HSCT seemed to have a lower death rate. The severity of aGVHD in the full matched HSCT was less than that in the haploidentical transplantation group. CONCLUSION: The primary choice of donor can be HLA-matched sibling donors or matched unrelated donors for children with AML with KMT2A rearrangements, and the secondary choice can be haploid donors.

[Treatment of Gaucher disease with allogeneic hematopoietic stem cell transplantation: report of three cases and review of literatures].

OBJECTIVE: To explore the efficacy of unrelated umbilical cord blood transplantation (UCBT) in the treatment of Gaucher disease. METHOD: The clinical characteristics of three children with Gaucher disease underwent UCBT in our hospital between April 2013 and September 2014 were retrospectively analyzed. Literature on allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the treatment of Gaucher disease was searched at Wanfang and Pubmed databases between 1983 and 2015 and was reviewed and summaried. RESULT: Three children with Gaucher disease, all were female, received UCBT. These patients' age at receiving transplantation was 3.8 years, 7.1 years and 2.6 years, respectively. The second case received the second transplantation. The first and third case received splenectomy before UCBT. The pretreatment regimen was busulfan (Bu)/fludarabine (Flu)/cyclophosphamide (CTX)/antithymocyte globulin (ATG), and for the patient received the second transplantation melphalan was added to the myeloablative conditioning regimen of Bu/Flu/CTX/ATG. Cyclosporine and mycophenolate mofetil (MMF) wee used for prophylaxis of acute graft versus host disease (aGVHD). The dose of cord blood stem cell nucleated cell counts was 9.7 × 107 /kg,11.9 × 107 /kg and 7.6 × 107/kg respectively. The dose of cord blood stem cell CD34⁺ cell counts was 5.4 × 105/kg , 3.5 × 105/kg and 3.2 × 105/kg respectively. The day of granulocytes exceeding 0.5 × 109/L was day 11, 12 and 19 after transplantation, respectively. The day of platelets exceeding 20 × 109/L was day 14, 33 and 74 after transplantation, respectively. At one month after transplantation the rate of chimerism was over 95% and all patients got donor complete chimerism. The level of ß-glucocerebrosidase recovered to normal at one month after transplantation. During transplantation, all patients developed cytomegalovirus (CMV) and Epstein-Barr virus (EBV) viremia. In case 1 immune thrombocytopenia occurred at five month after transplantation unresponding to steroids and mesenchymal stem cells infusion was administered and his platelet in routine blood test recovered to normal. But the patient died because she was infected with varicella-zoster virus out of hospital at nine month after transplantation and the level of ß-glucocerebrosidase was normal before death and chronic GVHD (cGVHD) was not found. The case 2 is now in 19th month after transplantation and his level of ß-glucocerebrosidase was normal. cGVHD was not found. The patient is currently free of disease. The case 3 was in 9th month after transplantation and his level of ß-glucocerebrosidase was normal. cGVHD was found at 112 day after transplantation and was localized and could be controlled by hormonal therapy. The patient is currently free of disease. Three patients' size of liver was significantly reduced after their level of ß-glucocerebrosidase ecovered. There were 50 cases with Gaucher disease who were treated with allo-HSCT in the literature and none of them were reported from China. Disease-free survival rate of patients treated with allo-HSCT for Gaucher disease was 85%. In all reports, there were 31 cases who had information of typing of Gaucher disease, of whom 22 cases had type 1 and 9 cases had type 3. Twenty-nine cases had information of survival, of whom 24 cases survived and 5 cases died of infection. Fifteen cases had data of engraftment, 2 of whom had graft failure and one had late graft failure.Glucocerebrosidase recovered to normal in 25 of 31 cases who had relevant data, in one of whom with late graft failure the enzyme recovered to normal 3 month after transplantation, but his enzyme decreased to the initial level 9 month after transplantation. Along with enzyme level's recovery to normal, in a part of cases bone pain and hepatomegaly were relieved and growth delay was improved. CONCLUSION: The unrelated UCBT may be a form of treatment that offers the potential of permanent cure and a procedure with possible long-term benefits in patients with Gaucher disease.

[Value of magnetic resonance imaging T2* tests in detecting heart and liver iron overload in patients with ß-thalassemia major].

OBJECTIVE: To assess the value of magnetic resonance imaging T2* tests in the detection of myocardial and liver iron overload in patients with ß-thalassemia major (ß-TM). METHODS: From 2010 to 2011, 28 ß-TM patients over 10 years old under blood transfusion therapy and chelation care with serum ferritin (SF)>1000 µg/L underwent myocardial and liver MRI T2* tests on a voluntary basis. The results were analyzed in relation with age, SF, and left ventricular ejection fraction (LVEF). RESULTS: Fourteen out of the 28 cases (50%) were found to have myocardial iron overload, including 7 severe cases, 2 moderate cases, and 5 mild cases. All the 28 cases had liver iron overload, including 2 mild cases, 7 moderate cases, and 19 severe cases. Two out of the 28 cases had lowered LVEF (7.14%), and one of them had severe myocardial iron overload. There was a negative correlation between myocardial MRI T2* and SF (r=-0.479, P=0.01). Myocardial MRI T2* was positively correlated with liver MRI T2* (r=0.378, P=0.047). Age was not significantly correlated with SF, LVEF, or liver MRI T2*. CONCLUSION: Magnetic resonance imaging (T2*) detection is an effective and non-invasive means for detecting myocardial and liver iron overload in patients with ß-thalassemia major receiving blood transfusion. T2* combined with SF is the main diagnostic indicator to assess iron overload in the vital organs.