Neurological complications of hematopoietic cell transplantation in children and adults

Progressive demyelinating polyneuropathy after hematopoietic cell transplantation in metachromatic leukodystrophy: a case series

Metachromatic leukodystrophy (MLD) is a neuro-metabolic disorder due to arylsulfatase A deficiency, causing demyelination of the central and peripheral nervous system. Hematopoietic cell transplantation (HCT) can provide a symptomatic and survival benefit for pre-symptomatic and early symptomatic patients by stabilizing CNS disease. This case series, however, illustrates the occurrence of severely progressive polyneuropathy shortly after HCT in two patients with late-infantile, one with late-juvenile, and one with adult MLD, leading to the inability to walk or sit without support. The patients had demyelinating polyneuropathy before HCT, performed at the ages of 2 years in the first two patients and at 14 and 23 years in the other two patients. The myeloablative conditioning regimen consisted of busulfan, fludarabine and, in one case, rituximab, with anti-thymocyte globulin, cyclosporine, steroids, and/or mycophenolate mofetil for GvHD prophylaxis. Polyneuropathy after HCT progressed parallel with tapering immunosuppression and paralleled bouts of infection and graft-versus-host disease (GvHD). Differential diagnoses included MLD progression, neurological GvHD or another (auto)inflammatory cause. Laboratory, electroneurography and pathology investigations were inconclusive. In two patients, treatment with immunomodulatory drugs led to temporary improvement, but not sustained stabilization of polyneuropathy. One patient showed recovery to pre-HCT functioning, except for a Holmes-like tremor, for which a peripheral origin cannot be excluded. One patient showed marginal response to immunosuppressive treatment and died ten months after HCT due to respiratory failure. The extensive diagnostic and therapeutic attempts highlight the challenge of characterizing and treating progressive polyneuropathy in patients with MLD shortly after HCT. We advise to consider repeat electro-neurography and possibly peripheral nerve biopsy in such patients. Nerve conduction blocks, evidence of the presence of T lymphocytes and macrophages in the neuronal and surrounding nerve tissue, and beneficial effects of immunomodulatory drugs may indicate a partially (auto)immune-mediated pathology. Polyneuropathy may cause major residual disease burden after HCT. MLD patients with progressive polyneuropathy could potentially benefit from a more intensified immunomodulatory drug regime following HCT, especially at times of immune activation.

Seizures in children undergoing stem cell transplantation

BACKGROUND

Neurological complications (NCs) are of major concern following hematological stem cell transplantation (HSCT), most of which present with seizures.

PROCEDURES

We performed a retrospective study (2002-2018) of patients undergoing HSCT in order to analyze the incidence and aetiologies related to seizures.

RESULTS

Of 155 children undergoing HSCT, 27 (17.4%) developed seizures at some point in 2 years of follow-up. The most frequent etiologies were central nervous system (CNS) infection (n = 10), drug toxicity (n = 8), and vascular disease (n = 5). A statistically significant association was found between seizure and the HSCT type (lower risk for a related identical donor, p = .010), prophylactic or therapeutic mycophenolate use (p = .043 and .046, respectively), steroid use (p = .023), selective CD45RA+ depletion (p = .002), pre-engraftment syndrome (p = .007), and chronic graft-versus-host disease (GVHD) severity (p = .030). Seizures predicted evolution to life-threatening complications and admission to intensive care (p < .001) and higher mortality (p = .023). A statistically significant association was also found between seizures and sequelae in survivors (p = .029). Children who developed seizures had a higher risk of CNS infection and vascular disease (odds ratio 37.25 [95% CI: 7.45-186.05] and 12.95 [95% CI 2.24-74.80], respectively).

CONCLUSIONS

Neurological complications highly impact survival and outcomes and need to be addressed when facing an HSCT procedure.

Hematologic malignancies and hematopoietic stem cell transplantation

Paraneoplastic neurologic syndromes are rarely associated with hematologic malignancies. In their rarity, lymphomas are the diseases with more frequent paraneoplastic neurologic syndrome. High-risk antibodies are absent in most lymphoma-associated paraneoplastic neurologic syndromes, with the exception of antibodies to Tr/DNER in paraneoplastic cerebellar degeneration, mGluR5 in limbic encephalitis, and mGluR1 in some cerebellar ataxias. Peripheral nervous system paraneoplastic neurologic syndromes are rare and heterogeneous, with a prevalence of demyelinating polyradiculoneuropathy in non-Hodgkin lymphoma. Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) is a rare, paraneoplastic syndrome due to an underlying plasma cell disorder. The diagnosis is based on defined criteria, and vascular endothelial growth factor (VEGF), not an antibody, is considered a reliable diagnostic marker that also mirrors therapy response. As with the paraneoplastic neurologic syndromes in solid tumors, therapies rely on cancer treatment associated with immunomodulatory treatment with better response in PNS with antibodies to surface antigens. The best outcome is generally present in Ophelia syndrome/limbic encephalitis with anti-mGluR5 antibodies, with frequent complete recovery. Besides patients with isolated osteosclerotic lesions (where radiotherapy is indicated), hematopoietic stem-cell transplantation is the therapy of choice in patients with POEMS syndrome. In the paraneoplastic neurologic syndromes secondary to immune checkpoint inhibitors, discontinuation of the drug together with immunomodulatory treatment is recommended.

Assignment of the antibacterial potential of Ag2O/ZnO nanocomposite against MDR bacteria Proteus mirabilis and Salmonella typhi isolated from bone marrow transplant patients

The rate of infectious diseases started to be one of the major mortality agents in the healthcare sector. Exposed to increased bacterial infection by antibiotic-resistant bacteria became one of the complications that occurred for bone marrow transplant patients. Nanotechnology may provide clinicians and patients with the key to overcoming multidrug-resistant bacteria. Therefore, this study was conducted to clarify the prevalence of MDR bacteria in bone marrow transplant recipients and the use of Ag2O/ZnO nanocomposites to treat participants of diarrhea brought on by MDR bacteria following bone marrow transplantation (BMT). Present results show that pathogenic bacteria were present in 100 of 195 stool samples from individuals who had diarrhea. Phenotypic, biochemical, and molecular analysis clarify that Proteus mirabilis and Salmonella typhi were detected in 21 and 25 samples, respectively. Successful synthesis of Ag2O/ZnO nanocomposites with a particle enables to inhibition of both pathogens. The maximum inhibitory impact was seen on Salmonella typhi. At low doses (10-5 g/l), it prevented the growth by 53.4%, while at higher concentrations (10-1 g/l), Salmonella typhi was inhibited by 95.5%. Regarding Proteus mirabilis, at (10-5 g/l) Ag2O/ZnO, it was inhabited by 78.7%, but at higher concentrations (10-1 g/l), it was inhibited the growth by 94.6%. Ag2O/ZnO nanocomposite was therefore found to be the most effective therapy for MDR-isolated bacteria and offered promise for the treatment of MDR bacterial infections that cause diarrhea.

Pre-engraftment neurological impairment in allogeneic stem cell transplant: A case report of atypical posterior reversible encephalopathy syndrome with pontine involvement

In the present report, we describe the case of a 59-year-old female who developed pre-engraftment multiple organ failure (MOF) after allogeneic hematopoietic stem cell transplant (HSCT), followed a few days later by a cohort of neurological symptoms leading to a diagnosis of posterior reversible encephalopathy syndrome (PRES). The diagnosis was achieved by excluding more frequent entities associated with neurological symptoms in HSCT and supported by compatible magnetic resonance imaging (MRI) findings, with remarkably interesting less frequent pontine involvement. GvHD prophylaxis, including sirolimus and mycophenolate mofetil (MMF), was discontinued, while carefully controlling blood pressure. In addition, high-dose steroids were employed. After 2 weeks, the neurological symptoms abated, and follow-up MRI showed a complete regression of neurological alterations, confirming the diagnostic hypothesis of PRES.

Limbic Encephalitis following Allogeneic Hematopoietic Stem Cell Transplantation

A woman with myelodysplastic syndrome (MDS) was treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). 65 days after the transplantation, she developed fatigue and central neurological symptoms. Clinical workup including magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) examination revealed findings suspicious for limbic encephalitis (LE), successfully treated with intravenous immunoglobulins and intravenous corticosteroids. Although a rare complication after allo-HSCT, physicians should be aware of neurological symptoms that develop throughout the transplantation course.

Neurologic Complications in Pediatric Allogeneic Stem Cell Transplantation: Analysis of Risk Factors and Outcome

Neurologic complications following stem cell transplantation are of utmost importance owing to their high morbimortality. Although many studies have been performed in the adult population, reports in children are scarce. Our objective was to determine the most common neurologic complications in a pediatric population and to analyze possible risk factors for their development. We performed an exploratory retrospective study of neurologic complications in pediatric patients who had allogeneic stem cell transplantation over the last 18 years. We identified 66 neurologic complications in 178 allogeneic stem cell transplantations. The most frequent neurologic complications were those involving the peripheral nervous system and those related to drug toxicity. Survival decreased significantly in the presence of neurologic complications. Multivariate logistic regression analysis showed that independent risk factors for developing neurologic complications were development of chronic extensive graft-vs-host disease requiring treatment, cytomegalovirus reactivation, and central nervous system radiation. Prompt diagnosis and preemptive treatment, if possible, are necessary to avoid long-term sequelae or mortality.

Neurological complications following pediatric allogeneic hematopoietic stem cell transplantation: Risk factors and outcome

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (HSCT) is an efficient treatment for numerous malignant and nonmalignant conditions affecting children. This procedure can result in infectious and noninfectious neurological complications (NCs).

OBJECTIVE

The objective of the study is to examine the incidence, risk factors, and outcomes of NCs in pediatric patients following allogeneic HSCT.

METHODS

We performed a retrospective study of 746 children who underwent 943 allogeneic HSCTs in two large pediatric hospitals in Israel from January 2000 to December 2019.

RESULTS

Of the pediatric patients 107 (14.3%) experienced 150 NCs. The median follow-up was 55 months. Noninfectious NCs were more common than infectious NCs (81.3% vs. 18.7%). Factors significantly associated with type of NC (infectious vs. noninfectious) were underlying disease (immunodeficiency vs. malignant and metabolic/hematologic disease) (p-value = 0.000), and use of immunosuppressive agent, either Campath or ATG (p-value = 0.041). Factors with a significant impact on developing neurological sequelae post-NC were number of HSCT >1 (p-value = 0.028), the use of alemtuzumab as an immunosuppressive agent (p-value = 0.003), and infectious type of NC (p-value = 0.046). The overall survival rate of whole NC-cohort was 44%; one-third of all mortality cases were attributed to the NC. The strongest prognostic factors associated with mortality were older age at HSCT (p-value = 0.000), the use of alemtuzumab as an immunosuppressive agent (p-value = 0.004), and the existence of neurological sequelae (p-value = 0.000). Abnormal central nervous system imaging (p-value = 0.013), the use of alemtuzumab as an immunosuppressive agent (p-value = 0.019), and neurological sequelae (p-value = 0.000) had statistically significant effects on neurological cause of death.

CONCLUSION

Infectious and noninfectious NCs are a significant cause of morbidity and mortality following allogeneic HSCT in children. Further research is required to better understand the risk factors for different NCs and their outcomes regarding sequelae and survival.

Neurological complications in Chinese children undergoing hematopoietic stem cell transplantation

BACKGROUND

Hematopoietic stem cell transplantation, despite being a curative treatment for various pediatric disorders, is associated with significant acute and chronic complications.

METHODS

This retrospective review of 196 hematopoietic stem cell transplantation episodes (144 allogeneic, 52 autologous) performed in a tertiary pediatric unit focused on neurological symptoms and complications occurred from the start of conditioning to within 3 years of transplantation. Indications for transplantation included both benign and malignant diseases. For episodes involving allogeneic transplantation, 42% of donors were matched-unrelated, 19% were matched-sibling, and 12% were haploidentical.  RESULTS: Neurological complications developed in 17% of all hematopoietic stem cell transplantation episodes. Tumors of central nervous system and leukemia or lymphoma were two indications reported to have higher incidence of 42% and 21%, respectively. The occurrence of neurological complications was significantly associated with primary diagnosis (p = 0.01), central nervous system involvement by underlying disease (p = 0.001), and radiation-based conditioning (p = 0.018). Upon multivariate analysis, central nervous system involvement by underlying disease remained to be the only significant factor (p = 0.019), while radiation-based containing conditioning (p = 0.029) is revealed to be associated when considering allogeneic transplantation alone. Pre-transplant central nervous system-directed treatment, allogeneic versus autologous donor, stem cell source, donor type, busulfan use, and cyclosporin use were not significantly associated with neurological complications. Patients with neurological complications were also found to have an inferior 2-year overall survival (53.9% ± 8.8% versus 63.8% ± 4.2%; p = 0.016).

CONCLUSION

Neurological complications were common in pediatric hematopoietic stem cell transplantation and were associated with adverse outcome; non-radiation containing conditioning regimens might be beneficial in mitigating the risk of such complications.

Patterns of central nervous system complications of post-hematopoietic stem cell transplant in pediatric oncology patients: a single institute experience

Background

Hematopoietic stem cell transplant (HSCT) has been increasingly used in the last few decades, with improved success in offering a cure. CNS complications are an important contributor to morbidity and mortality in HSCT patients. The aim of the study was to evaluate the role of imaging in the detection and assessment of CNSC (central nervous system complications) after HSCT in pediatric oncology patients.

The study included consecutive pediatric patients who underwent HSCT for hematologic or solid malignancies at CCHE-57357 (Children Cancer Hospital–Egypt 57357) from January 2011 to March 2019. The age of the patients in the study ranged from 0.9 to 25 years (median age 6.5 years). CT (computed tomography) and/or MRI (magnetic resonance imaging) studies were evaluated for the detection and characterization of CNSC.

Results

The incidence of post-HSCT CNSC was 13% with a day 100 and 5-year cumulative incidence of 9.3 and 12.5%, respectively. The most commonly observed CNSC detected was disease recurrence, followed by PRES (Posterior reversible encephalopathy syndrome). CNS recurrence of the initial diagnosis, atrophy, and infection were more common at the > 100-day post-HSCT transplant period, while PRES was much more common at < 100-day post-HSCT.

Conclusion

CNS complications are an important contributor to morbidity and mortality in HSCT patients that require MRI protocols distinctively tailored for each patient, clinical suspicion, and proper imaging assessment for early detection and follow-up.

Neurologic complications of acute myeloid leukemia. Diagnostic approach and therapeutic modalities

Acute myeloid leukemia (AML) comprises a heterogeneous group of aggressive blood malignancies that arise from clonal expansion of malignant hematopoietic precursor cells in the bone marrow. Neurologic manifestations of these malignancies are manifolds. AML is the most common form of acute leukemia in adults and this review describes the neurologic complications in this age group. Neurologic symptoms and signs may develop in AML either from a direct neoplastic involvement of the central or the peripheral nervous system or as an indirect effect of the disease process. Direct involvement of the nervous system includes invasion of the central or the peripheral nervous system (parenchymal and leptomeningeal dissemination, myeloid sarcoma, neuroleukemiosis). Thrombotic and hemorrhagic events are common manifestations of indirect involvement of the nervous system and they are the outcome of hyperleukocytosis, thrombocytopenia and coagulopathy. Many neurologic complications are iatrogenic and include diverse categories such as lumbar puncture and intrathecal or systemic chemotherapy and targeted therapies, radiotherapy and allogeneic stem cell transplantation. Most neurologic manifestations require urgent treatment and confer a poor prognosis. This review describes the neurologic complications of acute myeloid malignancies in the era of contemporary treatment. Those manifestations require expert consideration of their origin as they are being identified with increasing frequency as patients survive longer.

Imaging findings of neurologic complications in lung transplantation: Review of a 9-year cohort

Background

Lung transplantation (LT) requires complex multidisciplinary organization and constitutes a therapeutic option and a life-saving procedure. Although the number of lung recipients continues to increase, neurological complications and death rates following lung transplantation are still higher than desirable.

Purpose

This study aims to analyse the neuroimaging findings in a cohort of adult patients with LT.

Material and Methods

A retrospective cohort study of all lung transplant recipients (344 patients: 205 men and 139 women) at a single institution from January 2011 to January 2020. The collected data included demographic features, clinical data and evaluation of the imaging findings. We also recorded the date of neurological complication(s) and the underlying disease motivating lung transplantation.

Results

We found an elevated rate of neuroimaging findings in patients following LT with 32.6% of positive studies. In our cohort, the average time after LT to a neurological complication was 4.9 months post-transplant. Encephalopathy, critical illness polyneuropathy and stroke, in that order, were the most frequent neurological complications. Structural abnormalities in brain imaging were more often detected using MRI than CT for indications of encephalopathy and seizures.

Conclusions

LT recipients constitute an especially vulnerable group that needs close surveillance, mainly during the early post-transplant period.

Acute Graft-Versus-Host Disease, Infections, Vascular Events and Drug Toxicities Affecting the Central Nervous System

Allogeneic hematopoietic cell transplantation (allo-HCT) is a curative therapy for patients with hematological malignancies. Acute Graft versus host diseases (GVHD) is a major immune mediated side effect of allo-HCT that can affect the central nervous system (CNS) in addition to post-allo-HCT vascular events, drug toxicity or infections. Here we summarize and discuss recent preclinical data on the CNS as a target of acute GVHD and the known mechanisms contributing to neurotoxicity with a focus on microglia and T cells. We also discuss open questions in the field and place the findings made in mouse models in a clinical context. While in mice the neurological deficits can be assessed in a controlled fashion, in patients the etiology of the CNS damage is difficult to attribute to acute GVHD versus infections, vascular events, and drug-induced toxicity. Ultimately, we discuss novel therapies for GVHD of the CNS. Our understanding of the biological mechanisms that lead to neurotoxicity after allo-HCT increased over the last decade. This review provides insights into CNS manifestations of GVHD versus other etiologies of CNS damage in mice and patients.

Post-transcriptional and translational control of the morphology and virulence in human fungal pathogens

Host-pathogen interactions at the molecular level are the key to fungal pathogenesis. Fungal pathogens utilize several mechanisms such as adhesion, invasion, phenotype switching and metabolic adaptations, to survive in the host environment and respond. Post-transcriptional and translational regulations have emerged as key regulatory mechanisms ensuring the virulence and survival of fungal pathogens. Through these regulations, fungal pathogens effectively alter their protein pool, respond to various stress, and undergo morphogenesis, leading to efficient and comprehensive changes in fungal physiology. The regulation of virulence through post-transcriptional and translational regulatory mechanisms is mediated through mRNA elements (cis factors) or effector molecules (trans factors). The untranslated regions upstream and downstream of the mRNA, as well as various RNA-binding proteins involved in translation initiation or circularization of the mRNA, play pivotal roles in the regulation of morphology and virulence by influencing protein synthesis, protein isoforms, and mRNA stability. Therefore, post-transcriptional and translational mechanisms regulating the morphology, virulence and drug-resistance processes in fungal pathogens can be the target for new therapeutics. With improved "omics" technologies, these regulatory mechanisms are increasingly coming to the forefront of basic biology and drug discovery. This review aims to discuss various modes of post-transcriptional and translation regulations, and how these mechanisms exert influence in the virulence and morphogenesis of fungal pathogens.

Epileptic Seizures After Allogeneic Hematopoietic Stem Cell Transplantation

Technique in allogeneic hematopoietic stem cell transplantation has greatly advanced over the past decades, which has led to an increase in the number of patients receiving transplantation, but the complex procedure places these transplant recipients at high risk of a large spectrum of complications including neurologic involvement. As a common manifestation of neurological disorders, epileptic seizures after transplantation have been of great concern to clinicians because it seriously affects the survival rate and living quality of those recipients. The aim of this review is to elucidate the incidence of seizures after allogeneic hematopoietic stem cell transplantation, and to further summarize in detail its etiologies, possible mechanisms, clinical manifestations, therapeutic schedule, and prognosis, hoping to improve doctors' understandings of concurrent seizures following transplantation, so they can prevent, process, and eventually improve the survival and outlook for patients in a timely manner and correctly.

Hematopoietic Stem Cell Transplantation-Associated Neurological Complications and Their Brain MR Imaging Findings in a Pediatric Population

Simple Summary

Neurologic complications following a hematopoietic stem cell transplantation (HSCT) can be caused by various etiologies and significantly contribute to morbidity and mortality. The aim of our retrospective study was to determine the prognostic indicators for HSCT-associated neurological complications in pediatric HSCT recipients using their clinical characteristics and brain magnetic resonance imaging (MRI) lesions. The demographics, received treatments, treatment-related morbidities, laboratory findings and brain MRI findings were reviewed and compared among 51 patients who had underwent a brain MRI due to newly developed neurological symptoms or infection signs during HSCT and follow-up period. Children with neurologic complications associated with infectious causes, malignant disease or severe brain MRI abnormalities were more likely to have poor outcome.

Abstract

Purpose: To determine the prognostic indicators for hematopoietic stem cell transplantation (HSCT)-associated neurological complications, the clinical characteristics and brain magnetic resonance imaging (MRI) lesions in pediatric HSCT recipients were reviewed. Methods: This retrospective study included 51 patients who had underwent a brain MRI due to newly developed neurological symptoms or infection signs during chemotherapy or HSCT. We reviewed the demographics, received treatments, treatment-related morbidities, laboratory findings and brain MRI findings, which were compared between good and poor neurologic outcome groups. Results: Thirty-seven patients (72.5%) fully recovered from the neurologic deficits and fourteen (27.5%) persisted or aggravated. The children with an underlying malignant disease had significantly poorer neurological outcomes (p = 0.015). The neurologic complications associated with infection were more frequent in the poor outcome group (p = 0.038). In the neuroimaging findings, the extent of the white matter lesions was significantly higher in the poor outcome group, as was that of abnormal enhancement, ventriculomegaly, cortical change, deep gray matter abnormalities and cerebellar abnormalities. Conclusion: Most children with neurologic complications and neuroimaging abnormalities during HSCT had recovered. However, children with neurologic complications associated with infectious causes, malignant disease or severe brain MRI abnormalities should be more carefully monitored during HSCT.

Cyclosporine A-related neurotoxicity after haploidentical hematopoietic stem cell transplantation in children with hematopathy

Background

To evaluate cyclosporine A (CSA)-related neurotoxicity after haploidentical hematopoietic stem cell transplantation (HID-HSCT) in children with hematopathy.

Methods

This retrospective case series study included children with hematopathy who underwent HID-HSCT at Fujian Medical University Union Hospital between February 2013 and January 2017.

Results

Fifty-one children (39 males) were included in the study with a median age of 8 (range, 1.1–18) years. Seven patients (13.7%) developed CSA-related neurotoxicity after a median 38 (range, − 3 to 161) days from HID-HSCT. Hypertension (5/7, 71%) was the most common prodrome. Brain magnetic resonance imaging showed posterior reversible encephalopathy syndrome in six patients and atypical abnormalities in one patient. One patient died from grade IV graft-versus-host disease (GvHD) on day + 160, and six patients were alive at the last follow-up. Four patients (71.4%) achieved complete remission, while two patients developed secondary epilepsy and exhibited persistent MRI and electroencephalogram abnormalities at the 5-year follow-up. Hypertension after CSA was more common in patients with CSA-related neurotoxicity than in those without (71% vs. 11%, P = 0.002). Five-year overall survival did not differ significantly between patients with CSA-related neurotoxicity (85.7 ± 13.2%) and those without (65.8 ± 7.2%).

Conclusions

The incidence of CSA-related neurotoxicity in children with hematopathy undergoing HID-HSCT is relatively high.

Noninvasive tools based on immune biomarkers for the diagnosis of central nervous system graft-vs-host disease: Two case reports and a review of the literature

BACKGROUND

Central nervous system graft-vs-host disease (CNS-GVHD) is a rare cause of CNS disorders after allogeneic hematopoietic stem cell transplantation. Currently, establishing a diagnosis of CNS-GVHD is challenging because the diagnostic criteria and diagnostic methods are not well defined and many confounding factors need to be ruled out.

CASE SUMMARY

Here, we present two patients with CNS-GVHD. Both patients with a history of acute GVHD or chronic GVHD developed neurological symptoms that could not be explained by other causes, and had abnormal cerebrospinal fluid (CSF) studies as determined by CSF and blood immune biomarker examinations, suggestive of suspected CNS-GVHD. Due to the lack of specific magnetic resonance imaging abnormalities and the rapid clinical deterioration of the patients, we did not attempt to perform a brain biopsy, but prompted the initiation of empirical immunosuppressive therapy. In view of the rapid and favorable response to local and systematic immunosuppressive treatment and the aforementioned neurologic manifestations together with CSF abnormalities and other negative findings, a final diagnosis of CNS-GVHD was made.

CONCLUSION

CSF and blood immune biomarker examinations facilitated the diagnosis of CNS-GVHD, which are particularly suitable for patients who are critically ill and require urgent treatment and for those who are unsuitable for invasive diagnostic procedures.

Perspective: A Framework to Screen Pediatric and Adolescent Hematopoietic Cellular Therapy Patients for Organ Dysfunction: Time for a Multi-Disciplinary and Longitudinal Approach

Hematopoietic Cell Transplantation (HCT) is a potentially curative therapy for children and adolescent/young adults (AYA) with high-risk malignancies as well as some non-malignant genetic diseases. However, HCT may be associated with endotheliopathies and/or organ dysfunction that may progress to pediatric multi-organ dysfunction syndrome (pMODS) and require critical care intervention. Discipline specific scoring systems may be used to characterize individual organ dysfunction, but the extent to which they are used to prospectively monitor HCT patients with mild dysfunction is unknown. Further, separate scoring systems may be used to define risk of mortality and inform prognostication among those who require critical care support. Our understanding of the epidemiology, risk factors, morbidity, mortality, required monitoring, optimal prevention strategies and appropriate management of children undergoing HCT who develop organ dysfunction, endotheliopathies and/or progress to pMODS is poor. Discipline-specific registries and clinical studies have described improving outcomes for children undergoing HCT, including those who require critical care support; however, longitudinal studies/prospective registries that capture common data elements among HCT patients with and without organ dysfunction, endotheliopathies and pMODS are needed to facilitate inter-disciplinary collaboration and optimally characterize the risk profiles, define screening and prophylaxis regimens and mitigate toxicity.

A Review of Acute and Long-Term Neurological Complications Following Haematopoietic Stem Cell Transplant for Paediatric Acute Lymphoblastic Leukaemia

Despite advances in haematopoietic stem cell transplant (HSCT) techniques, the risk of serious side effects and complications still exists. Neurological complications, both acute and long term, are common following HSCT and contribute to significant morbidity and mortality. The aetiology of neurotoxicity includes infections and a wide variety of non-infectious causes such as drug toxicities, metabolic abnormalities, irradiation, vascular and immunologic events and the leukaemia itself. The majority of the literature on this subject is focussed on adults. The impact of the combination of neurotoxic drugs given before and during HSCT, radiotherapy and neurological complications on the developing and vulnerable paediatric and adolescent brain remains unclear. Moreover, the age-related sensitivity of the nervous system to toxic insults is still being investigated. In this article, we review current evidence regarding neurotoxicity following HSCT for acute lymphoblastic leukaemia in childhood. We focus on acute and long-term impacts. Understanding the aetiology and long-term sequelae of neurological complications in children is particularly important in the current era of immunotherapy for acute lymphoblastic leukaemia (such as chimeric antigen receptor T cells and bi-specific T-cell engager antibodies), which have well-known and common neurological side effects and may represent a future treatment modality for at least a fraction of HSCT-recipients.

Standardized Semistructured Psychosocial Evaluation Before Stem Cell Transplantation Predicts Delirium After Transplant

BACKGROUND

Delirium affects many patients undergoing stem cell transplantation (SCT). Delirium is treatable, but prevention is a better goal, making it desirable to identify patients at heightened risk for delirium. A standardized pretransplant psychosocial assessment rating scale, the Stanford Integrated Psychosocial Assessment for Transplantation (SIPAT), has been demonstrated to predict outcomes in solid organ transplant recipients and nonadherence in patients with SCT.

OBJECTIVES

In this study, we aimed to evaluate the association of SIPAT score and post-SCT incident delirium.

METHODS

We retrospectively reviewed records of SCT recipients who had SIPAT evaluations before SCT, for indications of delirium in the 6 months after transplant. We tested the association between SIPAT score and delirium by logistic regression, controlling for relevant covariates such as transplant type (allogeneic vs autologous).

RESULTS

Of 85 patients (median age of 49 years, range 18-74), 56 (66%) were men, and 43 (50.5%) were autologous SCT recipients. The median pretransplant SIPAT score was 8, range 0-40. There were 15 cases (17.6%) of delirium in the 6 months following transplant.  In univariate analyses, transplant type was significantly associated with incident delirium. In multivariate analyses, SIPAT score was significantly associated with incident delirium (odds ratio, 1.090; P = 0.021).

CONCLUSIONS

Psychosocial risk as quantified by the SIPAT is associated with development of delirium in SCT recipients. This scale can therefore be integrated into medical risk models to anticipate which patients are at higher risk for delirium in their hospital course, enabling preventative measures tailored to the needs of the individual patient.

Standard treatment-refractory cytomegalovirus encephalitis unmasked by immune reconstitution inflammatory syndrome and successfully treated with virus-specific hyperimmune globulin

Objectives

Cytomegalovirus (CMV)‐related encephalitis is a rare but potentially life‐threatening complication of CMV infection in immunocompromised patients. The high mortality rate is associated with deficient immune system reconstitution after hematopoietic stem cell transplant (HSCT) and poor bioavailability of antiviral drugs in cerebrospinal fluid (CSF). CMV‐related central nervous system (CNS) infection may occur with aspecific symptoms, without evidence of either blood viral load or magnetic resonance imaging (MRI) signs of encephalitis.

Methods

Here, we describe a 10‐year‐old girl who underwent an allogeneic HSCT and subsequently developed CMV encephalitis. Because of the absence of CMV antigen in the blood, the diagnosis of encephalitis was proposed only after a delay, following the onset of immune reconstitution inflammatory syndrome (IRIS). Two months of combined dual antiviral therapy with ganciclovir and foscarnet proved ineffective against CMV and caused significant bone marrow and renal toxicity. To avoid further toxicity, the girl was given daily treatment with CMV‐hyperimmune globulins alone.

Results

After three weeks, the CSF viral load dropped significantly and was undetectable within three more weeks. In the meantime, the renal impairment resolved, and there was a complete bone marrow recovery.

Conclusion

We suggest that this patient succeeded in achieving CMV CSF clearance with high dose of CMV‐hyperimmune globulin, given alone, because of the ability of immunoglobulins to penetrate the blood–brain barrier (BBB).

Posterior Reversible Encephalopathy Syndrome after Allogeneic Stem Cell Transplantation in Pediatric Patients with Fanconi Anemia, a Prospective Study

Posterior reversible encephalopathy syndrome (PRES) is one of the most common neurologic complications following hematopoietic stem cell transplantation (HSCT). We aimed to evaluate the incidence, clinical, and imaging features of PRES in pediatric patients with Fanconi anemia (FA) following HSCT. This prospective study included all post-HSCT patients with underlying FA disease between 2014 and 2017. Brain computed tomography scan and magnetic resonance imaging (MRI) were performed in all individuals who developed neurologic symptoms. PRES was diagnosed based on clinic-radiological evidence. Follow-up MRI was performed in all patients with PRES within two months. Forty-one patients with FA (28 males; mean age, 8.19 ± 3.25 years) were enrolled. Out of 15 patients with acute neurologic symptoms, PRES was diagnosed in 9 individuals (21.95% of the total cohort). The occurrence of PRES was significantly higher in patients who had a donor with a 1-locus mismatch (P= .02). Donor relation, stem cell source, and graft-versus-host disease grade did not have any significant association with the development of PRES. MRI showed asymmetric vasogenic edema in 5 patients, an overt infarct in 1 patient, and foci of microhemorrhages in 3 patients, 1 of whom developed a hemorrhagic infarct. This patient died shortly, and persistent microhemorrhages were noted in the other 2 patients. Our findings demonstrate a greater risk of developing PRES after HSCT in patients with FA compared with those with other diseases (21.95% versus 1% to 10%), and in contrast to its term, it might be irreversible and has adverse effects on HSCT outcomes. The increased vascular and endothelial fragility in FA may contribute to the higher frequency of PRES in these individuals.

Autoimmunity Following Allogeneic Hematopoietic Stem Cell Transplantation

Autoimmune manifestations after allogeneic hematopoietic stem cell transplantation (AHSCT) are rare and poorly understood due to the complex interplay between the reconstituting immune system and transplant-associated factors. While autoimmune manifestations following AHSCT have been observed in children with graft-versus-host disease (GvHD), an alloimmune process, they are distinct from the latter in that they are generally restricted to the hematopoietic compartment, i.e., autoimmune hemolytic anemia, thrombocytopenia, and/or neutropenia. Autoimmune cytopenias in the setting of ASHCT represent a donor against donor immune reaction. Non-hematologic autoimmune conditions in the post-AHSCT setting have been described and do not currently fall under the GvHD diagnostic criteria, but could represent alloimmunity since they arise from the donor immune attack on the antigens that are shared by the donor and host in the thyroid, peripheral and central nervous systems, integument, liver, and kidney. As in the non-transplant setting, autoimmune conditions are primarily antibody mediated. In this article we review the incidence, risk factors, potential pathophysiology, treatment, and prognosis of hematologic and non-hematologic autoimmune manifestations in children after AHSCT.

Lentiviral gene therapy for X-linked chronic granulomatous disease

Chronic granulomatous disease (CGD) is a rare inherited disorder of phagocytic cells1,2. We report the initial results of nine severely affected X-linked CGD (X-CGD) patients who received ex vivo autologous CD34+ hematopoietic stem and progenitor cell-based lentiviral gene therapy following myeloablative conditioning in first-in-human studies (trial registry nos. NCT02234934 and NCT01855685). The primary objectives were to assess the safety and evaluate the efficacy and stability of biochemical and functional reconstitution in the progeny of engrafted cells at 12 months. The secondary objectives included the evaluation of augmented immunity against bacterial and fungal infection, as well as assessment of hematopoietic stem cell transduction and engraftment. Two enrolled patients died within 3 months of treatment from pre-existing comorbidities. At 12 months, six of the seven surviving patients demonstrated stable vector copy numbers (0.4-1.8 copies per neutrophil) and the persistence of 16-46% oxidase-positive neutrophils. There was no molecular evidence of either clonal dysregulation or transgene silencing. Surviving patients have had no new CGD-related infections, and six have been able to discontinue CGD-related antibiotic prophylaxis. The primary objective was met in six of the nine patients at 12 months follow-up, suggesting that autologous gene therapy is a promising approach for CGD patients.

Central nervous system disorders after hematopoietic stem cell transplantation: a prospective study of the Infectious Diseases Working Party of EBMT

We performed a prospective study to evaluate the types and characteristics of central nervous system (CNS) disorders in patients after hematopoietic stem cell transplantation. The study included 163 episodes of CNS disorders of which 58 (36%) were infections. Proven or probable infections were documented in 34 patients and included fungi (n = 10, 29%), viruses (n = 12, 35%), Toxoplasma spp. (n = 9, 27%) and bacteria (n = 3, 9%). Non-infectious neurological disorders (n = 105, 64%) frequently encompassed metabolic/drug-induced abnormalities (n = 28, 27%) or cerebral vascular events (n = 22, 21%). Median onset times were later for infectious (day + 101) vs non-infectious neurological disorders (day + 50, p = 0.009). An unremarkable cranial CT scan was found in 33% of infection episodes. Absence of cerebrospinal fluid pleocytosis despite a normal or increased peripheral blood white blood cell count occurred in 26% of infections. Day-30 mortality rates were significantly higher for fungal (87%) vs non-fungal infections (40%, p < 0.001). Significantly higher mortality rates were also documented for cerebral vascular events than for other non-infectious disorders (86% vs 34%, p < 0.001). Our prospective study shows that diagnostic findings in CNS infections might differ between hematopoietic stem cell transplant recipients and immunocompetent hosts. Special awareness and timely initiation of adequate diagnostics are crucial to improve the prognosis of these patients.

Cerebrovascular disease after allogeneic hematopoietic stem cell transplantation: incidence, risk, and clinical outcome

Cerebrovascular complications after hematopoietic stem cell transplantation (HSCT) cause serious morbidity and often contribute to mortality. The incidence, risk factors, and outcome of cerebrovascular disease (CVD) after allogeneic HSCT remain poorly defined. We retrospectively evaluated 459 adult patients who underwent allogeneic HSCT at a tertiary medical center between January 2003 and December 2015. A total of 20 patients (4.4%) developed post-transplant CVD. All cerebrovascular accidents occurred in the first two years post-transplant. The two-year incidences of post-transplant CVD, intracranial hemorrhage, and cerebrovascular infarction were 6.1%, 3.2%, and 3.2%, respectively. The incidence rate of CVD within two years after HSCT was 34.7 (95% CI 22.3 to - 53.7) per 1000 person-years, which was about tenfold higher than the general Taiwanese population. The only significant risk factor associated with post-transplant CVD is prior exposure to three or more courses of high-dose cytarabine. Post-transplant CVD is associated with dismal outcome and early mortality. The median overall survival of patients with post-transplant CVD was markedly reduced compared with those without CVD (8.0 vs. 60.6 months). Most patients with post-transplant CVD died within two months after the CVD events. Our study demonstrates that CVD remains a devastating complication after allogeneic HSCT in the modern era.

Pure Red Cell Aplasia (PRCA) and Cerebellar Hypoplasia as Atypical Features of Polyglandular Autoimmune Syndrome Type I (APS-1): Two Sisters With the Same AIRE Mutation but Different Phenotypes

The polyglandular autoimmune syndrome type I is a rare hereditary autosomal recessive disease. We describe a child with the classic triad of the disease and her sister with pure red cell aplasia and cerebellar hypoplasia. The latter received two haematopoietic stem cell transplantations, complicated by an acute disseminated encephalomyelitis.