Severe combined immunodeficiency (SCID) represents a group of genetically heterogeneous disorders characterized by mutations that lead to profound defects in both humoral and cellular immunity. Transplacental maternal engraftment (TME) is a frequently observed complication in SCID. While most cases of SCID with TME exhibit no substantial impact on disease progression, a subset of patients may encounter diagnostic delays or therapeutic challenges due to TME interference. Furthermore, TME may predispose these individuals to graft-versus-host disease (GVHD) prior to hematopoietic stem cell transplantation, thereby increasing diagnostic complexity and treatment risks. This review systematically examines the etiology and clinical manifestations of SCID associated with TME, analyzes its implications for disease management, and evaluates current detection methodologies. The synthesized evidence provides a theoretical foundation for future research and offers potential insights into the clinical diagnosis and management of SCID associated with TME.
Humans ; Severe Combined Immunodeficiency/diagnosis* ; Pregnancy ; Female ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Maternal-Fetal Exchange/immunology* ; Graft vs Host Disease/etiology* ; Animals ; Placenta/immunology*

This article reports the clinical characteristics and treatment processes of three cases of mucormycosis occurring after hematopoietic stem cell transplantation in children, along with a review of relevant literature. All three patients presented with chest pain as the initial symptom, and metagenomic next-generation sequencing (mNGS) confirmed the mucycete infection early in all cases. Two patients recovered after treatment, while one succumbed to disseminated infection. mNGS has facilitated early diagnosis and treatment, reducing mortality rates. Additionally, surgical intervention is an important strategy for improving the prognosis of this condition.
Humans ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Mucormycosis/etiology* ; Male ; High-Throughput Nucleotide Sequencing/methods* ; Child ; Female ; Metagenomics ; Child, Preschool

This report describes two cases of severe immune-mediated thrombocytopenia after allogeneic hematopoietic stem cell transplantation (HSCT) who were treated with umbilical cord mesenchymal stem cells (UC-MSCs). Case 1 was a child with severe aplastic anemia who underwent haploidentical bone marrow and peripheral blood HSCT, with a chimerism rate of 99.8% on day +25 and severe immune-mediated thrombocytopenia on day +60. After intravenous immunoglobulin (IVIG) pulse therapy, platelet count increased temporarily but then decreased, while cyclosporine, methylprednisolone, and rituximab had a poor therapeutic effect. Case 2 was a child with Gaucher's disease who underwent unrelated umbilical cord blood HSCT, with a chimerism rate of 96.35% on day +41 and severe immune-mediated thrombocytopenia on day +153. After three sessions of IVIG pulse therapy, the platelet count increased initially but subsequently decreased. Therapies with dexamethasone, prednisone, cyclosporine, and recombinant human thrombopoietin also yielded a poor response. Both children received three sessions of UC-MSCs infusion, and platelet counts increased and were subsequently maintained within the normal range. Case 1 has been followed up for 10 years and remains in disease-free survival. UC-MSCs infusion may be effective for severe immune-mediated thrombocytopenia that is unresponsive to first- and second-line therapies after HSCT and could potentially improve the quality of life and disease-free survival rate.
Child ; Humans ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Mesenchymal Stem Cell Transplantation ; Purpura, Thrombocytopenic, Idiopathic/etiology* ; Thrombocytopenia/therapy* ; Transplantation, Homologous ; Umbilical Cord/cytology*

OBJECTIVES: To evaluate the efficacy and safety of avatrombopag in promoting platelet engraftment after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children, compared with recombinant human thrombopoietin (rhTPO). METHODS: A retrospective analysis was conducted on 53 pediatric patients who underwent allo-HSCT at the Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences from April 2023 to August 2024. Based on medications used during the periengraftment period, patients were divided into two groups: the avatrombopag group (n=15) and the rhTPO group (n=38). RESULTS: At days 14, 30, and 60 post-transplant, platelet engraftment was achieved in 20% (3/15), 60% (9/15), and 93% (14/15) of patients in the avatrombopag group, and in 39% (15/38), 82% (31/38), and 97% (37/38) in the rhTPO group, respectively. There were no significant differences between the two groups in platelet engraftment rates at each time point, cumulative incidence of platelet engraftment, overall survival, and relapse-free survival (all P>0.05). Multivariable Cox proportional hazards analysis indicated that acute graft-versus-host disease was an independent risk factor for delayed platelet engraftment (P=0.043). CONCLUSIONS In children undergoing allo-HSCT, avatrombopag effectively promotes platelet engraftment, with efficacy and safety comparable to rhTPO, and represents a viable therapeutic option.
Humans ; Retrospective Studies ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Male ; Female ; Child ; Child, Preschool ; Infant ; Adolescent ; Transplantation, Homologous ; Blood Platelets/drug effects* ; Thiazoles/therapeutic use* ; Thrombopoietin/therapeutic use* ; Thiophenes

OBJECTIVES: To evaluate the safety and efficacy of thiotepa (TT)-containing conditioning regimens for allogeneic hematopoietic stem cell transplantation (HSCT) in children with inborn errors of immunity (IEI). METHODS: Clinical data of 22 children with IEI who underwent HSCT were retrospectively reviewed. Survival after HSCT was estimated using the Kaplan-Meier method. RESULTS: Nine patients received a traditional conditioning regimen (fludarabine + busulfan + cyclophosphamide/etoposide) and underwent peripheral blood stem cell transplantation (PBSCT). Thirteen patients received a TT-containing modified conditioning regimen (TT + fludarabine + busulfan + cyclophosphamide), including seven PBSCT and six umbilical cord blood transplantation (UCBT) cases. Successful engraftment with complete donor chimerism was achieved in all patients. Acute graft-versus-host disease occurred in 12 patients (one with grade III and the remaining with grade I-II). Chronic graft-versus-host disease occurred in one patient. The incidence of EB viremia in UCBT patients was lower than that in PBSCT patients (P<0.05). Over a median follow-up of 36.0 months, one death occurred. The 3-year overall survival (OS) rate was 100% for the modified regimen and 88.9% ± 10.5% for the traditional regimen (P=0.229). When comparing transplantation types, the 3-year OS rates were 100% for UCBT and 93.8% ± 6.1% for PBSCT (P>0.05), and the 3-year event-free survival rates were 100% and 87.1% ± 8.6%, respectively (P>0.05). CONCLUSIONS TT-containing conditioning for allogeneic HSCT in children with IEI is safe and effective. Both UCBT and PBSCT may achieve high success rates.
Humans ; Retrospective Studies ; Transplantation Conditioning/methods* ; Thiotepa/therapeutic use* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Male ; Female ; Child, Preschool ; Infant ; Child ; Transplantation, Homologous ; Graft vs Host Disease ; Adolescent

Diffuse alveolar hemorrhage (DAH) is a severe complication that can occur post- hematopoietic stem cell transplantation (HSCT). So far, the precise pathogenesis and risk factors of DAH post-HSCT remain elusive, diagnostic criteria have not reached a consensus, and the efficacy of existing therapeutic measures is far from satisfactory. At present, it is believed that the core mechanism of DAH post-HSCT is a vicious cycle initiated by endothelial injury, accompanied by a series of subsequent inflammatory and cellular responses. Treatment primarily focuses on managing inflammation, promoting hemostasis, and improving oxygenation. This paper reviews recent advances in understanding the pathogenesis, risk factors, clinical manifestations, diagnosis, and treatment of DAH following HSCT.
Humans ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Hemorrhage/etiology* ; Pulmonary Alveoli ; Lung Diseases/etiology* ; Risk Factors

OBJECTIVE: To analyze the factors associated with mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with severe aplastic anemia (SAA). METHODS: The clinical data of 90 children with SAA who received allo-HSCT in the Department of Hematology, Wuhan Children's Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from August 2016 to July 2023 were collected. The clinical features and causes of death were analyzed retrospectively. Cox proportional hazards model was used to screen the risk factors of death. RESULTS: Only 9 children died with a median time of 6.3(2.6, 8.3) months among the 90 children with SAA after allo-HSCT. Among the 5 deaths due to infection, 3 were pulmonary infection, including 2 cases of cytomegalovirus pneumonia. One case developed septic shock due to gastrointestinal infection. One case experienced graft failure, which was complicated by bloodstream infection, and developed septic shock. Three cases died of transplantation-associated thrombotic microangiopathy (TA-TMA). One case died of gastrointestinal graft-versus-host disease (GVHD). The results of multivariate analysis showed that post-transplant +60 d PLT≤30×10⁹/L (HR=7.478, 95%CI : 1.177-47.527, P =0.033), aGVHD Ⅲ-Ⅳ (HR=7.991, 95%CI : 1.086-58.810, P =0.041), and TA-TMA occurrence (HR=13.699, 95%CI : 2.146-87.457, P =0.006) were independent risk factors for post-transplant mortality. CONCLUSION Allo-HSCT is an effective therapy for SAA in children. Post-transplant +60 d PLT≤30×10⁹/L, aGVHD Ⅲ-Ⅳ, and TA-TMA occurrence are independently associated with post-transplant mortality, which may be helpful for early detection of potential high-risk children and optimization of clinical diagnostic and treatment strategies.
Humans ; Anemia, Aplastic/therapy* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Risk Factors ; Retrospective Studies ; Child ; Transplantation, Homologous ; Male ; Female ; Graft vs Host Disease ; Child, Preschool ; Proportional Hazards Models ; Adolescent ; Infant

OBJECTIVE: To investigate the role of MK2 inhibitor MMI-0100 on inflammatory response after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and related mechanisms. METHODS: An allo-HSCT mouse model was established. Recipient rats were randomly divided into BMT+NaCl group and BMT+MMI-0100 group, and were injected with NaCl and MMI-0100 every day after transplantation, respectively. Samples of the two groups were collected on d 7 and 14, femur paraffin sections were stained with HE, and pathological changes in the bone marrow cavity were observed under the light microscope. The gene and protein expression levels of pro-inflammatory cytokines IL-1β and IL-18 were detected by qPCR and Western blot. Macrophage typing was detected by flow cytometry. The expression levels of NLRP3 and Caspase-1 were detected by Western blot. RESULTS: Inflammatory cell infiltration in the bone marrow cavity was significantly reduced in the BMT+MMI-0100 group. Western blot results showed that the protein expression levels of IL-1β and IL-18 in the BMT+MMI-0100 group were decreased compared to the BMT+NaCl group on day 7 and day 14 (all P <0.01). The qPCR results showed that compared to the BMT+NaCl group, the IL-18 gene expression levels in the BMT+MMI-0100 group were significantly reduced on day 7 and day 14 (both P <0.01). In the BMT+MMI-0100 group, the expression level of IL-1β gene decreased on day 7 (P <0.05), but increased and was higher than that in the BMT+NaCl group on day 14 (P <0.05). Flow cytometry results showed that the expression of M1 macrophages and M1/M2 ratio decreased in the BMT+MMI-0100 group compared to BMT+NaCl group (all P <0.05). Western blot results showed that the protein expression levels of NLRP3 and Caspase-1 in the BMT+MMI-0100 group were lower than those in the BMT+NaCl group (all P <0.05). CONCLUSION MMI-0100 can ameliorate bone marrow inflammatory injury after allo-HSCT and may act by reducing NLRP3 expression to promote M2 polarization.
Animals ; Interleukin-1beta/metabolism* ; Rats ; Interleukin-18/metabolism* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Mice ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Inflammation ; Bone Marrow/pathology* ; Protein Serine-Threonine Kinases/metabolism* ; Intracellular Signaling Peptides and Proteins/antagonists & inhibitors* ; Caspase 1/metabolism* ; Macrophages ; Transplantation, Homologous

OBJECTIVE: To investigate the clinical features and risk factors associated with cutaneous chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children. METHODS: A retrospective analysis was conducted on the clinical data of children who underwent allo-HSCT in the Wuhan Children's Hospital from August 1, 2016, to December 31, 2023, and were regularly followed up for 1 year or more. The differences in clinical features between children with and without cutaneous cGVHD were compared, and the risk factors affecting the occurrence of cutaneous cGVHD were analyzed. RESULTS: During the study period, 296 children received allo-HSCT. Until December 31, 2024, follow-up showed that 20 children (6.8%) developed cutaneous cGVHD, which manifested as cutaneous lichenification, hyperpigmentation, keratosis pilaris, sclerotic changes, and hair or nail involvement. According to their skin lesion area and degree of grading, 5 cases were mild, 10 cases were moderate, and 5 cases were severe. Multivariate logistic regression analysis revealed that female donors and previous acute GVHD were risk factors for the development of cutaneous cGVHD after allo-HSCT. All 20 children were treated with glucocorticoid ± calcineurin inhibitors (tacrolimus/cyclosporine) as first-line therapeutic agents. Only 1 child improved after first-line treatment. The remaining 19 children treated with a second-line regimen of combination interventions based on individualized status, including 10 children who could not tolerate hormonotherapy or first-line treatment, and showed no significant improvement after 3 months, as well as 9 children with multi-organ cGVHD. After comprehensive second-line treatment, 17 children showed improvement in cutaneous symptoms. There were 3 deaths, including 1 due to primary disease recurrence and 2 due to pulmonary infections. CONCLUSION The skin is the first manifestation and most common organ involved in cGVHD in children. Cutaneous cGVHD severely affects the daily activities of transplanted children and requires prolonged immunosuppressive therapy, but has a favorable prognosis. First-line treatments for adults are not applicable to children who usually require a combination treatment with multiple drugs.
Humans ; Graft vs Host Disease/etiology* ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Retrospective Studies ; Risk Factors ; Female ; Child ; Skin Diseases/etiology* ; Chronic Disease ; Transplantation, Homologous ; Male ; Child, Preschool ; Adolescent

OBJECTIVES: To investigate the clinical characteristics of cytokine release syndrome (CRS) in children with thalassemia major (TM) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT) and their prognosis. METHODS: A retrospective analysis was performed for the clinical data of 280 children with TM who underwent haplo-HSCT in the Department of Hematology and Oncology, Shenzhen Children's Hospital, from January 2019 to December 2021. According to the CRS criteria, they were divided into two groups: CRS grade <3 (260 children) and CRS grade ≥3 (20 children). The children with TM were analyzed in terms of clinical characteristics of CRS after haplo-HSCT and their prognosis. RESULTS: There were significant differences between the two groups in neutrophil engraftment time, clinical manifestations of CRS, and the rate of use of glucocorticoids within 4 days after haplo-HSCT (P=0.012, 0.040, and <0.001 respectively). For the CRS grade <3 group, the incidence rate of acute graft-versus-host disease (aGVHD) was 9.6% within 3 months after transplantation, while no aGVHD was observed in the CRS grade ≥3 group within 3 months after transplantation, but there was no significant difference in the incidence of aGVHD between the two groups within 3 months after transplantation (P=0.146). No transplantation-related death was observed in either group within 3 months after haplo-HSCT. CONCLUSIONS The children with CRS grade≥3 have an early neutrophil engraftment time, severe and diverse clinical manifestations of CRS, and a high rate of use of glucocorticoids within 4 days after haplo-HSCT. For these children, early use of low-dose glucocorticoids after transplantation may alleviate CRS response and reduce the incidence of aGVHD, thereby bringing more benefits to the children. CRS after haplo-HSCT has no significant impact on the prognosis of the children.
Humans ; Hematopoietic Stem Cell Transplantation/adverse effects* ; Male ; Female ; Child ; Retrospective Studies ; Child, Preschool ; Graft vs Host Disease/prevention & control* ; beta-Thalassemia/therapy* ; Adolescent ; Cytokine Release Syndrome/etiology* ; Transplantation, Haploidentical/adverse effects* ; Infant ; Prognosis ; Glucocorticoids/therapeutic use*