Early and Late Neurological Complications after Reduced-Intensity Conditioning Allogeneic Stem Cell Transplantation

Encephalitis with Antibodies Against Glial Fibrillary Acidic Protein (GFAP) After Allogeneic Hematopoietic Stem Cell Transplantation: A Rare Case Report and Literature Review

In this report, the patient was a 57-year-old woman who had been diagnosed with aplastic anemia for 3 years. This patient underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). Twenty-four months after allo-HSCT, the patient experienced cognitive dysfunction, memory loss, and involuntary movements. Various central nervous system (CNS) complications may occur after allo-HSCT, which can lead to severe clinical problems. Diagnosis is often difficult because of the absence of distinctive clinical symptoms. In addition, different neurological disorders may show similar symptoms. Although antibodies in the CSF or serum have become well recognized in several CNS disorders, cases of autoimmune CNS disorders after allo-HSCT have rarely been reported. Here, we report the case of a patient who developed encephalitis associated with antibodies against glial fibrillary acidic protein (GFAP) after allo-HSCT. To the best of our knowledge, this is the first report of the involvement of antibodies against GFAP in post-transplantation encephalitis. Of course, all processes met the ethical and patient consents were obtained.

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.

Neurologic Complications of the Central Nervous System after Allogeneic Stem Cell Transplantation: The Role of Transplantation-Associated Thrombotic Microangiopathy as a Potential Underreported Cause

Neurologic complications (NCs), especially those of the central nervous system (CNS), represent a severe complication after allogeneic stem cell transplantation (allo-HSCT) and are associated with relevant morbidity and mortality. We aimed to characterize the potential risk factors for the development of CNS-NC, with a special focus on the role of calcineurin inhibitors (CNIs) as a predisposing factor. For this purpose, we compared cyclosporin A (CsA) versus tacrolimus (TAC) with respect to their influence on the incidence and type of CNS-NC after allo-HSCT. We retrospectively analyzed the incidence, risk factors, and impact on outcomes of CNS-NC diagnosed during the post-transplantation follow-up in patients with different high-risk hematologic malignancies who underwent allo-HSCT at our institution over a 20-year period. All patients included in the analysis received CNI (CsA or TAC) as graft-versus-host disease (GVHD) prophylaxis. We evaluated a total of 739 consecutive patients who underwent transplantation between December 1999 and April 2019. During a median follow-up of 6.8 years, we observed a CNS-NC incidence of 17%. The development of CNS-NC was associated with decreased overall survival (OS) and increased transplantation-related mortality (TRM). The most frequent CNS-NCs were infections (30%) and neurologic adverse events related to the administration of CNI, TAC, or CsA as GVHD prophylaxis (42%). In the multivariable analysis, age, total body irradiation (TBI), and severe acute GVHD and chronic GVHD were significant risk factors in the development of CNS-NCs. TAC compared with CsA emerged as an independent predisposing factor for CNS-NCs. The TAC-associated risk of CNS-NCs was related mostly to the occurrence of transplantation-associated thrombotic microangiopathy (TA-TMA) with neurologic manifestations (neuro-TA-TMA), although the general TA-TMA incidence was comparable in the 2 CNI subgroups. CNS-NCs are associated with poor prognosis after allo-HSCT, with TAC emerging as a potential yet insufficiently characterized predisposing factor.

Reduced Incidence of Neurologic Complications after Allogeneic Hematopoietic Stem Cell Transplantation with Calcineurin-Free Graft-versus-Host Disease Prophylaxis

Calcineurin inhibitors (CNIs), including cyclosporine and tacrolimus, are frequently associated with neurologic complications after allogeneic hematopoietic stem cell transplantation (HSCT). However, there is a lack of studies comparing the incidence and characteristics of neurologic complications in patients undergoing HSCT based on CNI-free or CNI-based GVHD prophylaxis. This retrospective single-center study analyzed the neurologic complications in 2 cohorts of patients undergoing HSCT with either CNI-based GVHD prophylaxis (n = 523) or CNI-free prophylaxis with post-transplantation cyclophosphamide, sirolimus, and mycophenolate mofetil (n = 371). The latter cohort included older patients and received more reduced-intensity conditioning and transplants from matched unrelated and haploidentical donors. The 2-year cumulative incidence of neurologic complications was significantly lower in the CNI-free cohort (6.9% versus 11.9%; P = .016), and GVHD prophylaxis was the sole statistically significant variable in multivariate analysis (hazard ratio, 2.2; 95% confidence interval [CI], .25 to 3.13; P = .0017). The distribution of neurologic types was similar in the 2 cohorts, with encephalopathy the most prevalent complication, except for headaches and myopathy, which decreased equally from 15% in the CNI-based cohort to 4% in the CNI-free cohort. Neurologic complications had negative impacts on mortality and survival rates, with a significantly higher 2-year cumulative incidence of nonrelapse mortality (NRM) (44% [95% CI, 34% to 54%] versus 16% [95% CI, 13% to 18%]; P < .0001) and inferior overall survival (66% [95% CI, 62% to 69%] versus 46% [95% CI, 37% to 58%]; P < .0001) in patients with neurologic complications. This study suggests that CNI-free GVHD prophylaxis with post-transplantation cyclophosphamide, sirolimus, and mycophenolate mofetil may reduce not only the incidence of GVHD incidence, but also the rates of neurologic complications and NRM, leading to improved survival outcomes in patients undergoing HSCT.

Long-term health outcomes of allogeneic hematopoietic stem cell transplantation

Background

Fifty years of hematopoietic cell transplantation (HCT) has ushered in an exciting era of cellular therapy and has led to enormous progress in improving the outcomes of patients with both malignant and non-malignant hematologic disease. As the survival of transplanted patients has increased, so has the recognition of long-term complications related to this therapy.

Purpose

The goal of this review is to highlight some of the most common long-term complications of HCT.

Data sources

To this end, we have conducted a review of the published literature on the long-term complications of HCT encompassing the past 50 years.

Study selection

We have endeavored to include long-term complications reported in research articles, case series and case reports, reviews, and abstracts. We have focused primarily on adult allogeneic HCT, but have included some data from studies of pediatric allogeneic HCT as well. We have also prioritized the literature published in the last 15 years.

Data extraction

Key data supporting the onset and prevalence of the most common long-term complications was extracted.

Limitations

While the list of long-term complications extracted and reported was comprehensive, it was not exhaustive.

Conclusions

We have endeavored to highlight some of the most common long-term complications of HCT, the recognition and management of which constitutes an important part of HCT survivorship care.

Towards a Better Understanding of the Atypical Features of Chronic Graft-Versus-Host Disease: A Report from the 2020 National Institutes of Health Consensus Project Task Force

Alloreactive and autoimmune responses after allogeneic hematopoietic cell transplantation can occur in non-classical chronic graft-versus-host disease (chronic GVHD) tissues and organ systems or manifest in atypical ways in classical organs commonly affected by chronic GVHD. The National Institutes of Health (NIH) consensus projects were developed to improve understanding and classification of the clinical features and diagnostic criteria for chronic GVHD. While still speculative whether atypical manifestations are entirely due to chronic GVHD, these manifestations remain poorly captured by the current NIH consensus project criteria. Examples include chronic GVHD impacting the hematopoietic system as immune mediated cytopenias, endothelial dysfunction, or as atypical features in the musculoskeletal system, central and peripheral nervous system, kidneys, and serous membranes. These purported chronic GVHD features may contribute significantly to patient morbidity and mortality. Most of the atypical chronic GVHD features have received little study, particularly within multi-institutional and prospective studies, limiting our understanding of their frequency, pathogenesis, and relation to chronic GVHD. This NIH consensus project task force report provides an update on what is known and not known about the atypical manifestations of chronic GVHD, while outlining a research framework for future studies to be undertaken within the next three to seven years. We also provide provisional diagnostic criteria for each atypical manifestation, along with practical investigation strategies for clinicians managing patients with atypical chronic GVHD features.

Neurological complications in adult allogeneic hematopoietic stem cell transplant patients: Incidence, characteristics and long-term follow-up in a multicenter series

Neurological complications (NCs) represent a diagnostic and clinical challenge in allogeneic hematopoietic stem cell transplant (alloHSCT) patients. We retrospectively analyzed NC incidence, etiology, timing, characteristics, outcome, and long-term effects in 2384 adult patients transplanted in seven Italian institutions between January 2007 and December 2019. Ninety-three (3.9%) patients were affected by 96 NCs that were infectious (29.2%), immune/inflammatory (26%), drug-related (12.5%), cerebrovascular (5.2%), metabolic (3.1%), related to central nervous system disease relapse (11.5%) and malignancy (3.1%), or undefined (9.4%). Six patients (6.4%) had neurological manifestations of chronic graft-versus-host disease (GVHD). NCs occurred on average at day +128 (from -5 to +4063). Early (< day +120) and late NCs had similar frequencies (46.9% vs 53.1%, p = 0.39). Thirty-one patients (33.3%) were affected by acute or chronic GVHD at the NC onset. With a median follow-up of 25.4 (0.4-163) months, the overall mortality due to NCs was 22.6%. The median time between NC onset and death was 36 (1-269) days. Infectious NCs were the main cause (61.9%) of NC-related mortality. A persistent neurological impairment occurred in 20.4% patients, 57.9% of whom being affected by immune/inflammatory NCs. This study highlights the rare, yet severe impact of alloHSCT-associated NCs on patient survival and long-term functional ability.

Predicting mortality from intracranial hemorrhage in patients who undergo allogeneic hematopoietic stem cell transplantation

Intracranial hemorrhage (ICH) is a rare but fatal central nervous system complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, factors that are predictive of early mortality in patients who develop ICH after undergoing allo-HSCT have not been systemically investigated. From January 2008 to June 2020, a total of 70 allo-HSCT patients with an ICH diagnosis formed the derivation cohort. Forty-one allo-HSCT patients with an ICH diagnosis were collected from 12 other medical centers during the same period, and they comprised the external validation cohort. These 2 cohorts were used to develop and validate a grading scale that enables the prediction of 30-day mortality from ICH in all-HSCT patients. Four predictors (lactate dehydrogenase level, albumin level, white blood cell count, and disease status) were retained in the multivariable logistic regression model, and a simplified grading scale (termed the LAWS score) was developed. The LAWS score was adequately calibrated (Hosmer-Lemeshow test, P > .05) in both cohorts. It had good discrimination power in both the derivation cohort (C-statistic, 0.859; 95% confidence interval, 0.776-0.945) and the external validation cohort (C-statistic, 0.795; 95% confidence interval, 0.645-0.945). The LAWS score is the first scoring system capable of predicting 30-day mortality from ICH in allo-HSCT patients. It showed good performance in identifying allo-HSCT patients at increased risk of early mortality after ICH diagnosis. We anticipate that it would help risk stratify allo-HSCT patients with ICH and facilitate future studies on developing individualized and novel interventions for patients within different LAWS risk groups.

Frequency and Risk Factors of Cyclosporine-Induced Neurotoxicity in Allogeneic Stem Cell Transplant Recipients

Background and objective

The calcineurin inhibitor cyclosporine A is routinely used for prophylaxis against graft-versus-host-disease (GvHD) in human leukocyte antigen (HLA)-matched allogeneic stem-cell transplant patients and is a major etiological factor for neuropathological symptoms that are reversible in most cases. In this study, we aimed to determine the frequency and risk factors of cyclosporine-induced neurotoxicity (CIN) in HLA-matched allogeneic stem cell transplant patients.

Methods

The study spanned the period from January 2016 to December 2019. Consecutive HLA-matched allogeneic stem-cell transplant patients of all ages were included in the study. Descriptive and risk factor analyses for the development of CIN with respect to age, sex, primary diagnosis, conditioning regimen, electrolyte abnormalities, and cyclosporine trough levels during the neurological episode were performed.

Results

A total of 106 HLA-matched patients with a median age of 6.3 years [interquartile range (IQR): 0.5-46 years], of which 37 (35%) were females, were included in the study. The mean cyclosporine trough level was 500 ±286 mg/dl. Neurological symptoms were found in 27 (26%) patients. A total of 14 (13%) patients were diagnosed with CIN. The frequency of other neurological symptoms included headache in 46 (43%), disorientation in 17 (16%), seizures in 12 (11%), visual disturbance in 11 (10%), and aphasia in seven (7%) patients. Posterior reversible encephalopathy syndrome (PRES) was found in six (6%) patients. All patients with CIN had hypertension and none had a fever. Multivariate logistic analysis showed that the presence of seizures [odds ratio (OR): 10.0, p<0.001] and the absence of fever (OR: 0.02, p<0.001) were associated with the diagnosis of CIN.

Conclusion

The prevalence of CIN is not uncommon (13%) in patients receiving cyclosporine for GvHD prophylaxis. Neurological complications, especially seizures, are common in CIN, and fever might indicate an alternative diagnosis. Prompt recognition of neurological signs and symptoms and early intervention can halt the progression of the disease.

Clinical risk factors and prognostic model for idiopathic inflammatory demyelinating diseases after haploidentical hematopoietic stem cell transplantation in patients with hematological malignancies

Idiopathic inflammatory demyelinating diseases (IIDDs) of the central nervous system (CNS) are rare but serious neurological complications of haploidentical hematopoietic stem cell transplantation (haplo-HSCT). However, the risk factors and a method to predict the prognosis of post-transplantation CNS IIDDs are not available. This retrospective study first reviewed data from 4532 patients who received haplo-HSCT during 2008-2019 in our center, and 184 patients (4.1%) with IIDDs after haplo-HSCT were identified. Grades II to IV acute graft-versus-host disease (aGVHD) (p < 0.001) and chronic GVHD (cGVHD) (p = 0.009) were identified as risk factors for developing IIDDs after haplo-HSCT. We then divided the 184 IIDD patients into a derivation cohort and validation cohort due to transplantation time to develop and validate a model for predicting the prognosis of IIDDs. In the multivariate analysis of the derivation cohort, four candidate predictors were entered into the final prognostic model: cytomegalovirus (CMV) infection, Epstein-Barr virus (EBV) infection, IgG synthesis (IgG-syn) and spinal cord lesions. The prognostic model had an area under the receiver operating characteristic curve of 0.864 (95% CI: 0.803-0.925) in the internal validation cohort and 0.871 (95% CI: 0.806-0.931) in the external validation cohort. The calibration plots showed a high agreement between the predicted and observed outcomes. Decision curve analysis indicated that IIDD patients could benefit from the clinical application of the prognostic model. The identification of IIDD patients after allo-HSCT who have a poor prognosis might allow timely treatment and improve patient survival and outcomes.

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.

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.

Metagenomic next-generation sequencing for identifying pathogens in central nervous system complications after allogeneic hematopoietic stem cell transplantation

A prospective study was conducted to compare metagenomic next-generation sequencing (mNGS) and conventional testing in investigating the pathogens of central nervous system (CNS) infections in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. A total of 53 patients with CNS disorders after allo-HSCT were enrolled in this study. A total of 35 patients were diagnosed as CNS infections, including 28 viral, 2 bacterial, 1 fungal, 3 mixed infections, and 1 infection with unknown pathogen. Among these 35 patients with CNS infections, mNGS identified 5 patients who were not identified by conventional testing. For the remaining 30 infections, mNGS made concurrent diagnoses with conventional testing in 29, while 1 was diagnosed according to the good response to the antimicrobial treatment without etiological evidence. The presence of Aspergillus detected by mNGS only in one patient was considered false positive due to lack of validation. The sensitivity of mNGS and conventional testing for diagnosing CNS infections post transplant were 97.1% and 82.9%, respectively (P = 0.106), while the specificity of mNGS and conventional testing were 94.4% and 100%, respectively (P = 1.000). These results suggest that mNGS might be a promising technology for diagnosis of CNS infections post transplant. Viruses were the most common pathogens of CNS infections in allo-HSCT recipients.

Acute Graft-versus-Host-Disease Other Than Typical Targets: Between Myths and Facts

Donor alloreactivity after allogeneic hematopoietic stem cell transplantation results in graft-versus-host reaction (GVHR) that may affect different organs. While skin, liver, and gastrointestinal tract are well-recognized targets of such alloreactivity early after transplant, commonly identified as acute graft-versus-host-disease (aGVHD), there is accumulating evidence from the literature that early GVHR may be directed also against other tissues. In particular, organs such as kidney, bone marrow, central nervous system, and lungs may be involved in patients experiencing aGVHD, but whether these sites represent targets or collateral damages of donor alloreactivity is matter of debate. This review summarizes the current knowledge, the potential applications, and the clinical relevance of GFHR in nontypical target organs during aGVHD. The objective of this article is to lay the basis for future efforts aiming at including these organs in grading and management of aGVHD.

Noninfectious neurologic complications of hematopoietic cell transplantation: A systematic review

OBJECTIVE/BACKGROUND

Neurological complications occur at a high frequency after hematopoietic cell transplantation (HCT). However, an absence is noted in the published literature as regards the quantification of the exact burden and the outcomes thereof. In this systematic review, we endeavored to detail if the recipients of HCT developed any noninfectious neurological events/complications.

METHODS

According to the PICO criteria, medical literature was searched. Complications that were evaluated included: stroke, peripheral neuropathy, myasthenia gravis, seizures, and posterior reversible encephalopathy syndrome. After strictly defining relevant variables and parameters, data from 173 eligible articles were then extracted accordingly, from the full text for each, for quantitative analysis; additionally, two American Society of Hematology conference abstracts were also subject to data extraction.

RESULTS

As is evident from the results of the data analysis, an increased frequency of these complications was seen in the HCT recipient population in comparison to the general population. The relative risk ranged from 1.33× to 142× depending on the complication studied.

CONCLUSION

These findings demonstrate that the recipients of HCT had a significantly higher risk of neurological complications and that their early recognition can enhance the monitoring of HCT survivors for the early developmental signs of neurological toxicity. This would facilitate timely interventions, thus ensuring a better quality of life.

Gait Analysis of Patients After Allogeneic Hematopoietic Cell Transplantation Reveals Impairments of Functional Performance

Background: After allogeneic hematopoietic cell transplantation (alloHCT), patients often report functional impairments like reduced gait speed and muscle weakness. These impairments can increase the risk of adverse health events similar to elderly populations. However, they have not been quantified in patients after alloHCT (PATs). Methods: We compared fear of falling (Falls Efficacy Scale–International) and temporal gait parameters recorded on a 10-m walkway at preferred and maximum gait speed and under dual-task walking of 16 PATs (aged 31-73 years) with 15 age-matched control participants (CONs) and 17 seniors (SENs, aged >73 years). Results: Groups’ gait parameters especially differed during the maximum speed condition: PATs walked slower and required more steps/10 m than CONs. PATs exhibited greater stride, stance, and swing times than CONs. PATs’ swing time was even longer than SENs’. The PATs’ ability to accelerate their gait speed from preferred to fast was smaller compared with CONs’. PATs reported a greater fear of falling than CONs and SENs. Conclusion: Gait analysis of alloHCT patients has revealed impairments of functional performance. Patients presented a diminished ability to accelerate gait and extending steps possibly related to a notable strength deficit that impairs power-generation abilities from lower extremities. Furthermore, patients reported a greater fear of falling than control participants and even seniors. Slowing locomotion could be a risk-preventive safety strategy. Since functional disadvantages may put alloHCT patients at a higher risk of frailty, reinforcing appropriate physical exercises already during and after alloHCT could prevent adverse health events and reduce the risk of premature functional aging.

A Case of Multiple Sclerosis-Like Relapsing Remitting Encephalomyelitis Following Allogeneic Hematopoietic Stem Cell Transplantation and a Review of the Published Literature

Complications involving the central nervous system (CNS) occur in 9–14% of patients following allogeneic hematopoietic stem cell transplantation (HSCT), including stroke-like episodes, demyelination, encephalitis, and nonspecific neurological symptoms. Here we report a case of multiple sclerosis (MS) like relapsing remitting encephalomyelitis following allogeneic HSCT, which did not respond to disease modifying therapies (DMTs) and “domino” autologous HSCT. A 53-year-old male was treated with allogeneic HSCT for lymphoid blast transformation of chronic myeloid leukemia. Ten months later he presented with confusion, slurred speech, left sided facial weakness and ataxia. A magnetic resonance imaging brain scan showed multiple enhancing tumefactive lesions. Neuromyelitis optica (NMO) and myelin oligodendrocyte glycoprotein (MOG) antibodies were negative. After extensive investigations for infections, autoimmune disorders and recurrence of malignancy, he underwent brain biopsy, which showed a macrophage rich lesion with severe myelin loss but axonal preservation indicating a demyelinating pathology. Although his symptoms improved with corticosteroids, he relapsed five months later. In the absence of any systemic features suggesting graft versus host disease (GvHD), his presentation was thought to be compatible with MS. The illness followed an aggressive course that did not respond to glatiramer acetate and natalizumab. He was therefore treated with “domino” autologous HSCT, which also failed to induce long-term remission. Despite further treatment with ocrelizumab, he died of progressive disease. An autopsy limited to the examination of brain revealed multifocal destructive leukoencephalopathy with severe myelin and axonal loss. Immunohistochemistry showed macrophage located in the perivascular area, with no T or B lymphocytes. The appearance was unusual and not typical for chronic MS plaques. Reported cases of CNS demyelination following allogeneic HSCT are very limited in the literature, especially in relation to histopathological examination. Although the clinical disease course of our patient following allogeneic HSCT resembled an “MS-like” relapsing remitting encephalomyelitis, the autopsy examination did not show any evidence of active inflammation. The impact of DMTs and HSCT on the histological appearance of “MS-like” CNS pathologies is unknown. Therefore, reporting this and similar cases will improve our awareness and understanding of underlying disease mechanisms.

Rituximab for acute demyelinating myelopathy after allogeneic hematopoietic stem cell transplantation: a case report

Acute demyelinating myelopathy after allogeneic hematopoietic stem cell transplantation (HSCT) is rare, and the exact pathogenesis remains unclear. Here, we report the case of a 20-year-old patient with B-cell acute lymphocyte leukemia (B-ALL) who developed acute demyelinating myelopathy approximately 10 months after HSCT. Magnetic resonance imaging revealed high T2 signal intensity lesions from the C2-T4 levels of the spinal cord. Treatments with high doses of corticosteroids, immunoglobulins, and rituximab improved his neurologic symptoms, and he achieved 44 months of leukemia-free and graft-versus-host disease (GVHD)-free survival, with no recurrence of the demyelination myelopathy. An understanding of the contribution of immune reconstitution to the pathogenesis of demyelinating myelopathy after HSCT and the association of this disease with GVHD will require more clinical cases.

Central Nervous System Complications after Allogeneic Hematopoietic Stem Cell Transplantation in Children

Central nervous system complications (CNSCs) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are common and may be a significant source of morbidity and mortality. We performed a retrospective study of 153 pediatric patients who underwent allo-HSCT to determine CNSC type, incidence, and impact on survival. A total of 34 patients (22.2%) developed CNSCs. The cumulative incidence of CNSCs at 100 days and 3 years was 18.30 and 22.73%, respectively. The most common CNSC was calcineurin inhibitor (CNI)-associated neurotoxicity (50.0%). Risk factors for CNSCs were the time from diagnosis to HSCT ≥4.8 months (p = 0.032) and the development of acute graft-versus-host disease (aGVHD) grade III-IV (p = 0.002). CNSCs after allo-HSCT negatively impacted overall survival (hazard ratio [HR] 1.97, p = 0.043) and nonrelapse mortality (HR 4.84, p < 0.001). In conclusion, CNSCs after allo-HSCT are associated with poor outcomes; patients with severe aGVHD and/or late transplantation should be given more attention.

Noninfectious Neurologic Complications after Allogeneic Hematopoietic Stem Cell Transplantation

Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) can be associated with neurologic complications, data on noninfectious etiologies are scanty. Therefore, we analyzed the incidence, clinical characteristics, risk factors, and influence on outcomes of noninfectious neurologic complications (NCs) in 971 consecutive patients with hematologic malignancies undergoing allo-HSCT at our center between January 2000 and December 2016. We evaluated NCs affecting the central nervous system (CNS) and peripheral nervous system (PNS). The median duration of follow-up of survivors was 71 months (range, 11 to 213 months). A total of 467 patients received a matched sibling donor (MSD) transplant, 381 received umbilical cord blood (UCB), 74 received a haploidentical transplant, and 49 received a matched unrelated donor (MUD) transplant. One hundred forty-nine (15.3%) NCs were documented at a median of 78 days after transplantation (range, 5 days before to 3722 days after). The cumulative incidence risk of developing NC was 7.5% (95% confidence interval, 6% to 8.2%) at day +90 and 13% at 5 years. The 5-year cumulative incidence of NCs was 10.8% after MSD allo-HSCT and 15.3% after alternative donor (UCB, MUD, haploidentical) allo-HSCT (P = .004). There were 101 (68%) CNS complications, including encephalopathy, n = 46 (31%); headache, n = 20 (13%); stroke, n = 15 (10%); seizures, n = 9 (6%), posterior reversible encephalopathy syndrome, n = 6 (4%), and myelopathy, n = 5 (3%). PNS complications (32%) included neuropathies, n = 25 (17%), and myopathies and neuromuscular junction disorders, n = 23 (17%), with 17% of the total PNS complications being immune-related. In multivariable analysis, donor type other than MSD, age ≥40 years, development of acute graft-versus-host disease (GVHD) grade II-IV (hazard ratio [HR], 3.3; P < .00001), and extensive chronic GVHD (HR, 3.2; P = .0002) were independently associated with increased risk of NCs. The 5-year overall survival (OS) was 21% in patients who developed NCs and 41% for those who did not (P < .0001). This difference in OS was observed in patients developing CNS NCs, but not in those developing PNS complications. In conclusion, our study reveals NCs as a frequent and heterogeneous complication that, when affecting CNS, is associated with poor prognosis following allo-HSCT.

Neurological adverse events post allogeneic hematopoietic cell transplantation: major determinants of morbidity and mortality

BACKGROUND

Despite advances in the field, diagnosis and management of the wide spectrum of neurological events post allogeneic hematopoietic cell transplantation (alloHCT) remain challenging. Therefore, we investigated their incidence, diagnosis, management and long-term prognosis in alloHCT recipients.

METHODS

We retrospectively recorded data from consecutive alloHCT recipients with or without neurological complications in our center.

RESULTS

Among 758 alloHCT recipients, 127 (16.8%) presented with neurological complications. Complications developed in central nervous system (89.7%) during the late post-transplant period. Neurological adverse events included a wide spectrum of infectious and non-infectious etiologies. With a median follow-up of 11.4 months, incidence of chronic graft-versus-host disease (GVHD) was 52.8%, relapse mortality 48.6%, transplant-related mortality 39.1% and 5-year overall survival (OS) 25.8% in patients with neurological complications. Timing of appearance of neurological complications, early or late, was associated only with acute and chronic graft-versus-host-disease/GVHD. Independent pre-transplant risk factors of neurological complications in the multivariate model were unrelated or alternative donors, ALL diagnosis and non-myeloablative conditioning. In multivariate analysis of post-alloHCT events, favorable OS was independently associated with resolution of neurological syndromes, absence of chronic GVHD and sibling transplantation. In our cohort, 10-year OS was significantly lower in patients with neurological complications and independently associated with acute and chronic GVHD, relapse, fungal and bacterial infections and neurological complications.

CONCLUSIONS

Our large study with long-term follow-up highlights the wide spectrum of neurological complications in alloHCT. Accurate recognition is required for adequate management, a major determinant of survival. Thus, long-term increased awareness and collaboration between expert physicians is warranted.

Incidence, Risk Factors, and Outcome of Immune-Mediated Neuropathies (IMNs) following Haploidentical Hematopoietic Stem Cell Transplantation

Immune-mediated neuropathies (IMNs) following hematopoietic stem cell transplantation have been described recently, which, excluding Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, may present with atypical patterns. This retrospective, nested, case-control study reviewed data from 3858 patients who received haploidentical hematopoietic stem cell transplantation (haplo-HSCT) during the past 10 years at a single center, and 40 patients (1.04%) with IMN following haplo-HSCT were identified. Chronic graft-versus-host disease (cGVHD) (P = .043) and cytomegalovirus (CMV) viremia (P = .035) were recognized as independent risk factors for the development of IMN after haplo-HSCT. There were no significant differences in overall survival (P = .619), disease-free survival (P = .609), nonrelapse mortality (P = .87), or the incidence of relapse (P = .583) between patients with and without IMN after haplo-HSCT. However, patients with post-transplant IMN were at higher risk of developing cGVHD (P = .012) than patients who did not develop IMN. Twenty-four of the 40 patients with IMN (60%) attained neurologic improvement after treatments including vitamins B₁ and B₁₂ and/or immunomodulatory agents. However, 19 (47.5%) patients still had persistent motor/sensory deficits despite receiving timely treatment. More studies are needed to help develop standardized diagnostic and therapeutic strategies for patients with post-transplant IMN.

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.

[Post-transplant neurological complications: Guidelines from the francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC)]

Neurological complications post-allogeneic hematopoietic stem cell transplantation are well-characterized; however, given their variable impact, they remain a significant cause of morbidity. The etiologies for these complications are vast. Causes may be linked to toxicity and infection or could be vascular or tumor-related. Regardless, these complications require early investigation, which is often multidisciplinary and hierarchical. Preventive measures may be considered in some situations. It is essential to respond early and quickly with a diagnosis and the appropriate therapeutic approach when faced with neurological complications. Focusing on the axes of etiology, diagnosis and treatment, this article offers a review of neurological complications post-allogeneic hematopoietic stem cell transplantation.

Alemtuzumab-containing reduced intensity conditioning allogenic hematopoietic stem cell transplantation in a case of primary progressive multiple sclerosis

Increasing evidence has emerged lately regarding the use of autologous hematopoietic stem cell transplantation (HSCT) in the treatment of aggressive multiple sclerosis (MS). However, data is scarce regarding the use of allogenic HSCT in treating MS. We present a 42 years old male with aplastic anemia who underwent allogenic HSCT for severe aplastic anemia. This patient was diagnosed with primary progressive multiple sclerosis (PPMS) one-year post transplant and had to undergo a second HSCT due to his hematological disorder. His second HSCT was conditioned with an alemtuzumab containing regimen, after which his MRI and expanded disability status scale (EDSS) remained to be stable for 18 months.

IgG synthesis rate and anti-myelin oligodendrocyte glycoprotein antibody in CSF may be associated with the onset of CNS demyelination after haplo-HSCT

Haploidentical hematopoietic stem cell transplant (haplo-HSCT) is an upfront and effective therapy for hematology patients, but it usually has many complications, such as neurological complications. As one of the neurological complications following haplo-HSCT, immune-mediated demyelinating diseases of the central nervous system (CNS) seriously affect a patient's quality of life. However, the incidence, risk factors, and pathogenesis of CNS demyelination are not very well understood. Thirty of the 1526 patients (1.96%) suffered from CNS demyelination. In univariate analysis, we found that blood-brain barrier (BBB) permeability and the CSF IgG synthesis index (IgG-Syn) were related to the occurrence of CNS demyelination (p < 0.05). In a multivariate analysis, the IgG-Syn (OR = 1.017, 95% CI 1.003-1.031, p = 0.019) and CSF anti-myelin oligodendrocyte glycoprotein antibody (MOG.Ab) (OR = 12.059, 95% CI 1.141-127.458, p = 0.038) were independently associated with the onset of CNS demyelination. We also studied the possible pathogenesis of CNS demyelination. Immune reconstitution (the cell proportions of CD19⁺ B cells, CD3⁺ T cells, and CD4⁺ T cells); the counts of leucocytes, lymphocytes, monocytes, and platelets; and the levels of immunoglobulins A, G, and M 30, 60, and 90 days after HSCT showed no significant differences between CNS demyelination and no demyelination (p > 0.05). The probabilities of overall survival showed no significant differences between patients with and without demyelination (p > 0.05). Only four deaths in 30 patients, but bringing projected survival to less than 20%.We imply that IgG-Syn and CSF MOG. Ab may be associated with the onset of CNS demyelination during 2 weeks of neurological symptoms in patients with brain or spinal cord MRI abnormality. Immune reconstitution may not be the pathogenesis of CNS demyelination.

Neurologic complications after allogeneic hematopoietic stem cell transplantation: risk factors and impact

Neurologic complications (NCs) may be a significant source of morbidity and mortality after hematopoietic cell transplantation (HCT). We performed a retrospective study of 263 consecutive patients undergoing allogeneic HCT for hematological malignancies to determine the incidence, risk factors and clinical impact of NCs in the first 5 years after HCT. We determined the incidence of central nervous system (CNS) infection, intracranial hemorrhage, ischemic stroke, metabolic encephalopathy, posterior reversal encephalopathy syndrome, seizure and peripheral neuropathy. In all, 50 patients experienced 63 NCs-37 early (⩽day +100), 21 late (day +101 to 2 years) and 5 very late (2 to 5 years). The 1- and 5-year cumulative incidences of all NCs were 15.6% and 19.2%, respectively, and of CNS complication (CNSC; all of the above complications except peripheral neuropathy) were 12.2 and 14.5%. Risk factors for CNSC were age (hazard ratio (HR)=1.06 per year, P=0.0034), development of acute GvHD grade III-IV (HR=2.78, P=0.041), transfusion-dependent thrombocytopenia (HR=3.07, P=0.025) and delayed platelet engraftment (>90th centile; HR=2.77, P=0.043). CNSCs negatively impacted progression-free survival (HR=2.29, P=0.0001), overall survival (HR=2.63, P<0.0001) and non-relapse mortality (HR=8.51, P<0.0001). NCs after HCT are associated with poor outcomes, and usually occur early after HCT.

Central nervous system complications after allogeneic hematopoietic stem cell transplantation

Allogenic hematopoietic stem cell transplant (alloSCT) is a potentially curative modality of treatment for patients with hematological malignancies. However, CNS complications following transplant pose a risk to survival of the patients. Early recognition and management of these complications are crucial to reduce morbidity and mortality of patients following transplant. Early CNS complications associated with alloSCT are infection, cerebrovascular events, chemotherapy and radiation-induced toxicities while late complications include post-transplant lymphoproliferative disorder, CNS relapse of underlying malignancy and viral and fungal infections. Development of graft-versus-host disease can further increase the risk of CNS complications and outcomes after alloSCT. Strategies aimed to reduce the risk of CNS complications and early management may ameliorate the morbidity and mortality in transplant recipients.

Neurological Complications Involving the Central Nervous System After Allogeneic Hematopoietic Stem Cell Transplantation During a Period of Evolution in Transplant Modalities: A Cohort Analysis

BACKGROUND

Neurological complications (NC) after hematopoietic stem cell transplantation (HSCT) are rare events. The evolution of transplant procedures has resulted in improved survival and has allowed elderly patients or those with comorbidity to receive an HSCT. The risk of NC in these patients has still not been well defined. Therefore, we carried out an observational study to estimate the occurrence and identify the risks associated with NC.

METHODS

The study cohort included 452 adult-allogeneic HSCT recipients, transplanted from 1997 to 2012. The median follow up was 1.3 year (0-15.7). A myeloablative regimen was used in 307 patients. Two hundred patients were grafted from matched unrelated donor (MUD), of these, 129 (64.5%) received an in vivo T-cell depletion.

RESULTS

Out of 452 patients, 30 (6.6%) developed NC. Infections were the most frequent causes of NC (30%). Overall survival decreased in patients developing NC (P < 0.001). Univariate survival regression on the cumulative incidence of NC identified period of transplant, linear trend between 4-year periods (1997-2012) (P < 0.001), MUD (P < 0.001), and recipient's age (P = 0.034) as significant risk factors. In multivariate analysis, period of transplant (P < 0.001) and MUD (P = 0.004) remained significant independent risk factors. Matched unrelated donor recipients showed a 3.8-fold elevated risk of developing NC.

CONCLUSIONS

Analysis highlights a temporal trend of incidence of NC that progressively increased over time and confirms a strong association between donor type and risk of NC. Our observations suggest that, although relatively uncommon, NC after allo-HSCT, may become more frequent due to the improved overall survival in recent years.

Visual evoked potentials after hematopoietic allogeneic stem cell transplantation in childhood

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VEP recordings were abnormal in 17% of the patients median 6 years post hematopoietic stem cell transplantation in childhood.

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Pathological VEPs were associated with decreased visual acuity.

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Pathological VEPs were not linked to irradiation, chemotherapy or malignant diagnosis.

Objective

To study visual pathway pathology detected by visual evoked potentials (VEPs) in patients treated with hematopoietic stem cell transplantation (HSCT) in childhood and to determine the impact of adverse ocular findings, somatic diseases, and conditioning regimens on the VEP results.

Methods

Ophthalmological assessments including pattern VEPs were performed in 47 of 79 patients at a median age of 15 years (range 3–21 years) in median 6 years (1–17 years) after HSCT. Somatic data were extracted from medical records.

Results

Eight patients of 47 (17%) demonstrated pathological VEPs with prolonged latencies bilaterally (n = 3) or unilaterally (n = 5) at their latest VEP test at an age of 12–18 years. A subnormal visual acuity was present in 8/11 eyes with pathological VEPs: one eye had cataract, six eyes had cataract surgery where of two had developed secondary cataracts. One eye had residual retinopathy of prematurity. Pathological VEPs were associated with decreased visual acuity (p = 0.00019) but not linked to gender, malignant diagnosis or conditioning.

Conclusion

VEP recordings showed an association with decreased visual acuity but no relationship with irradiation or chemotherapy in the present study.

Significance

VEP recordings might be of clinical value for children with an unexplained subnormal visual acuity undergoing HSCT.

Neurologic Complications after Allogeneic Hematopoietic Stem Cell Transplantation

Neurologic complications after hematopoietic stem cell transplantation are frequently life-threatening, and their clinical management can be highly challenging. A wide spectrum of causative factors-including drug-related toxicities; infections sustained by virus, bacteria, or invasive molds; metabolic encephalopathy; cerebrovascular disorders; immune-mediated disorders; and disease recurrence-may lead to potentially lethal complications. Moreover, given that some neurologic complications are not uncommonly diagnosed post mortem, their overall incidence is likely to be underestimated. Their prompt recognition and timely treatment are of paramount importance to reduce the risk for transplantation-related death.

Infections of the Central Nervous System after Unrelated Donor Umbilical Cord Blood Transplantation or Human Leukocyte Antigen-Matched Sibling Transplantation

We analyzed the incidence, clinical characteristics, prognostic factors, and outcome of central nervous system (CNS) infections in consecutive patients with receiving umbilical cord blood transplantation (UCBT) (n = 343) or HLA-matched sibling donor stem cell transplantation (MST) (n = 366). Thirty-four CNS infections were documented at a median time of 116 days after transplantation (range, 7 to 1161). The cumulative incidence (CI) risk of developing a CNS infection was .6% at day +30, 2.3% at day +90, and 4.9% at 5 years. The 5-year CI of CNS infection was 8.2% after UCBT and 1.7% after MST (P < .001). The causative micro-organisms of CNS infections were fungi (35%), virus (32%), Toxoplasma spp. (12%), and bacteria (12%). Fungal infections occurred in 11 patients after UCBT and 1 after MST and were due to Aspergillus spp. (n = 8), Cryptococcus neoformans (n = 2), Scedosporium prolificans (n = 1), and Mucor (n = 1). Except for 1 patient, all died from CNS fungal infection. Viral infections occurred in 9 patients after UCBT and 1 after MST and were due to human herpes virus 6 (n = 7), cytomegalovirus (n = 2), and varicella zoster virus (n = 1). CNS toxoplasmosis was diagnosed in 3 patients after UCBT and 1 after MST. Other pathogens were Staphylococcus spp, Nocardia spp, Streptococcus pneumoniae, and Mycobacterium tuberculosis. Twenty of the 34 patients (59%) died from the CNS infection. In multivariable analysis, UCBT and disease stage beyond first complete remission were independently associated with the risk of developing CNS infections. The 5-year overall survival was 19% in patients who developed a CNS and 39% for those who did not (P = .006). In conclusion, our study showed that CNS infections are a significant clinical problem after stem cell transplantation associated with poor survival. They were more frequent after UCBT compared to MST.

Central nervous system infection following allogeneic hematopoietic stem cell transplantation

OBJECTIVE/BACKGROUND

Here, we described the clinical characteristics and outcomes of central nervous system (CNS) infections occurring after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in a single institution over the previous 6 years.

METHODS

Charts of 353 consecutive allogeneic transplant recipients were retrospectively reviewed for CNS infection.

RESULTS

A total of 17 cases of CNS infection were identified at a median of 38 days (range, 10-1028 days) after allo-HSCT. Causative pathogens were human herpesvirus-6 (n=6), enterococcus (n=2), staphylococcus (n=2), streptococcus (n=2), varicella zoster virus (n=1), cytomegalovirus (n=1), John Cunningham virus (n=1), adenovirus (n=1), and Toxoplasma gondii (n=1). The cumulative incidence of CNS infection was 4.1% at 1 year and 5.5% at 5 years.

CONCLUSION

Multivariate analysis revealed that high-risk disease status was a risk factor for developing CNS infection (p=.02), and that overall survival at 3 years after allo-HSCT was 33% in patients with CNS infection and 53% in those without CNS infection (p=.04).

Central Nervous System Complications of Hematopoietic Stem Cell Transplant

Hematopoietic stem cell transplantation (SCT) is now commonly used to treat several hematologic and nonhematologic diseases. Central nervous system (CNS) complications post-transplantation occur commonly in the first year and result in increased mortality from infectious, toxic, metabolic, or vascular causes. Infections secondary to aspergillus, toxoplasma and viruses cause many of the complications. Drug-related toxicities arising from conditioning regimens and graft-versus-host disease prophylaxis, as well as intraparenchymal hemorrhage, are not uncommon and can result in increased morbidity. Secondary CNS cancers have a higher incidence 5 or more years after allogeneic SCT.

Complete neurologic and cognitive recovery after plasmapheresis in a patient with chronic inflammatory demyelinating polyneuropathy after allogeneic hematopoietic stem cell transplantation

Neurologic complications after allogeneic hematopoietic stem cell transplantation (HSCT) are rare but poorly understood. We present a case report of a 57-year-old-male patient who was diagnosed in 2009 with acute myeloid leukemia (AML). He received two standard induction chemotherapies, as well as a following consolidation. Six months later, an allogeneic HSCT was performed. Shortly after HSCT the patient developed progressive polyneuropathy of the lower legs and hypoesthesia. Five months later a severe dementia followed. All images of the brain and spine showed no specific pathologies. High dose corticosteroids and immunoglobulins did not improve the neurologic symptoms. Due to severe worsening of the neuropsychiatric status and the clinical presentation, chronic inflammatory demyelinating polyneuropathy (CIDP) was suspected. Therefore, the patient received ten cycles of plasmapheresis. The patient showed a significant improvement of the neuropsychiatric symptoms and cognitive status. CONCLUSIONS: Immune mediated neuropathies after allogeneic HSCT, such as CIDP, have great variability in symptoms and presentation and are challenging to diagnose and treat. Plasmapheresis is a safe and efficient treatment for patients with unclear persisting autoimmune neuropathy after HSCT.

Cerebral salt-wasting syndrome after hematopoietic stem cell transplantation in adolescents: 3 case reports

Cerebral salt-wasting syndrome (CSWS) is a rare disease characterized by a extracellular volume depletion and hyponatremia induced by marked natriuresis. It is mainly reported in patients who experience a central nervous system insult, such as cerebral hemorrhage or encephalitis. The syndrome of inappropriate antidiuretic hormone secretion is a main cause of severe hyponatremia after hematopoietic stem cell transplantation, whereas CSWS is rarely reported. We report 3 patients with childhood acute leukemia who developed CSWS with central nervous system complication after hematopoietic stem cell transplantation. The diagnosis of CSW was made on the basis of severe hyponatremia accompanied by increased urine output with clinical signs of dehydration. All patients showed elevated natriuretic peptide and normal antidiuretic hormone. Aggressive water and sodium replacement treatment was instituted in all 3 patients and 2 of them were effectively recovered, the other one was required to add fludrocortisone administration.

Clinical Management of Posterior Reversible Encephalopathy Syndrome after Allogeneic Hematopoietic Stem Cell Transplantation: A Case Series and Review of the Literature

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a rare but serious complication after allogeneic hematopoietic stem cell transplantation (alloHSCT). Among others, calcineurin inhibitors (CNI) for prophylaxis of graft-versus-host disease (GvHD) may promote the development of PRES, but the pathomechanism is still controversial. Discontinuation of CNI facilitates remission of symptoms but might contribute to the unfavorable prognosis of PRES due to an elevated incidence of GvHD.

METHODS

This is a case series of 7 patients with PRES from a retrospective analysis of 146 consecutive patients who received alloHSCT for hematologic malignancies.

RESULTS

At the onset of PRES, all patients presented a systemic infection, while no influence was seen for underlying disease, conditioning regimen, donor type, or GvHD. Discontinuation of CNI and control of the blood pressure reversed neurological symptoms in 6 patients, while 1 patient died from septic multiorgan failure. After bridging with prednisolone and/or mycophenolic acid, replacement of CNI by the mammalian target of rapamycin (mTOR) inhibitor everolimus effectively prevented severe GvHD without recurrence of PRES.

CONCLUSIONS

A systemic infection/inflammation may be an important cause of PRES. Prophylaxis of GvHD by the mTOR inhibitor everolimus in case of PRES after alloHSCT demonstrated promising results but needs to be validated in larger cohorts.

Severe fludarabine neurotoxicity after reduced intensity conditioning regimen to allogeneic hematopoietic stem cell transplantation: a case report

We present a case of severe, irreversible neurotoxicity in a 55-year-old-patient with myelofibrosis undergoing hematopoietic stem cell transplantation following a reduced intensity conditioning including fludarabine. The patient developed progressive sensory-motor, visual and consciousness disturbances, eventually leading to death. MRI imaging pattern was unique and attributable to fludarabine neurotoxicity.

Neurologic complications after allogeneic hematopoietic stem cell transplantation in children: analysis of prognostic factors

Neurologic complications are serious complications after hematopoietic stem cell transplantation (HSCT) and significantly contribute to morbidity and mortality. The purpose of this study was to investigate the clinical features and prognosis in pediatric patients who had neurologic complications after allogeneic HSCT. We retrospectively reviewed the medical records of children and adolescents (19 years old or younger) who underwent allogeneic HSCT at our institution from 2000 to 2012. A total of 383 patients underwent 430 allogeneic transplantations. Among them, 73 episodes of neurologic complications occurred in 70 patients. The cumulative incidence of neurologic complications at day 400 was 20.0%. Almost two thirds of the episodes (63.0%, 46 of 73) occurred within 100 days after transplantation. Calcineurin inhibitor-related neurotoxicity was observed as the most common cause of neurotoxicity (47.9%, 35 of 73) and was significantly associated with earlier onset neurologic complications, seizure, and tremor. It also showed a significant association with lower probability of headache, abnormality of cranial nerve, and neurologic sequelae. In a multivariate analysis, days to neutrophil engraftment after HSCT, extensive chronic graft-versus-host disease (GVHD) and the existence of neurologic sequelae were identified as risk factors for mortality in patients who had neurologic complications (hazard ratio [HR], 1.08; 95% confidence interval [CI], 1.02 to 1.15; P = .011; HR, 5.98; 95% CI, 1.71 to 20.90; P = .005; and HR, 4.37; 95% CI, 1.12 to 17.05; P = .034, respectively). However, there was no significant difference in the 5-year overall survival between the patients who had neurologic complications without sequelae and the patients who did not have any neurologic complications (57.3% versus 61.8%, P = .906). In conclusion, we found that the major significant risk factors for mortality in pediatric recipients with neurologic complications were the existence of neurologic sequelae and extensive chronic GVHD.

Metabolische Störungen

Im folgenden Kapitel werden die verschiedenen metabolischen Störungen betrachtet. Zunächst wird auf die allgemeinen und spezifischen neurologischen Komplikationen bei Organtransplantation eingegangen. Dann geht es um die metabolischen Enzephalopathien: Störungen der Gehirntätigkeit bei angeborenen und erworbenen Stoffwechselerkrankungen im engeren Sinn, Elektrolytstörungen, Hypovitaminosen, zerebrale Folgen einzelner Organdysfunktionen, zerebrale Hypoxien, Endotheliopathien und Mitochondropathien. Anschließend werden das Alkoholdelir und die Wernicke-Enzephalopathie erörtert. Bei zahlreichen akuten Erkrankungen von Gehirn, Rückenmark und peripherem Nervensystem treten typische Störungen vegetativer Systeme auf, deren Erkennung und Therapie insbesondere bei Intensivpatienten eine vitale Bedeutung haben kann: die autonomen Störungen. Bei der zentralen pontinen Myelinolyse kommt es zu einer akuten, vorwiegend fokal-symmetrischen Demyelinisierung im Hirnparenchym. Auch Basalganglienerkrankungen können intensivmedizinisch relevant werden. Und schließlich wird die akute Stressreaktion betrachtet, die aufgrund der vielfältigen metabolischen und endokrinen Veränderungen bei kritischen Erkrankungen entsteht. Gerade das RCVS als neuere Krankheitsentität und wichtige Differenzialdiagnose zur Vaskulitis des ZNS verdient einen eigenen Platz, in diesem Unterkapitel werden ebenfalls verwandte Syndrome wie die hypertensive Enzephalopathie und das PRES abgehandelt.

Autoimmune Demyelinating Polyneuropathy as a Manifestation of Chronic Graft-versus-Host Disease after Adult Cord Blood Transplantation in a Patient with Chronic Lymphocytic Leukemia

Immune mediated demyelinating disease after allogeneic stem cell transplantation is a rare entity with unclear etiology. Acute inflammatory demyelinating polyneuropathy (AIDP) has been reported after related and adult unrelated allogeneic stem cell transplantation but no such case has been reported after unrelated cord blood transplantation. We hereby present the first case of AIDP after double umbilical cord blood transplantation (DUCBT). A 55-year-old man with chronic lymphocytic leukemia (CLL) received a cord blood transplant for relapsed refractory disease with high risk cytogenetics. On day 221, patient presented with skin rash, tingling in both lower extremites, and ascending paralysis that progressed rapidly over the course of 2 days. The workup resulted in a diagnosis of AIDP and administration of intravenous immunoglobulins plus steroids was initiated. Motor and sensory powers were fully recovered and his chronic GVHD was managed for several months with single agent sirolimus.

Neurologic complications of bone marrow transplantation

Although bone marrow transplantation has been recognized as an effective therapy for malignant and nonmalignant blood disorders, the modality has also been associated with side-effects and complications. Among these adverse events, neurologic complications emerged as an important and frequent source of treatment-related morbidity and mortality. The survival of patients who died from complications related to central nervous system abnormalities appears to be shorter compared to those who died from non-neurological complications. The incidence of neurologic complications appears to correlate with the degree of human leukocyte antigen (HLA) disparity and the risk status of the underlying disease. Nonrelapse mortality associated with reduced intensity regimens is lower compared to myeloablative conditioning regimens. However, reduced intensity regimens are still associated with significant incidence of complications, including graft-versus-host disease, opportunistic infections, organ toxicity, and neurologic complications. Complications of sepsis-related encephalopathy in mechanically ventilated patients are frequently either overlooked or misdiagnosed. Obtaining a microbiological diagnosis through body fluid cultures or tissue identification is important in order to identify the source of infection and guide an effective antimicrobial therapy. However, pursuing a microbiological diagnosis must not delay the administration of antibiotics and resuscitation of a patient with septic shock.

Neurological complications of transplantation: part I: hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) is the preferred treatment for an expanding range of neoplastic and nonmalignant conditions. Increasing numbers of solid organ transplantations (SOTs) add an additional population of immunosuppressed patients with multiple potential neurological problems. While the spectrum of neurological complications varies with conditioning procedure and hematopoietic cell or solid organ source, major neurological complications occur with all transplantation procedures. This 2 part review emphasizes a practical consultative approach to central and peripheral nervous system problems related to HCT or SOT with clinical and neuroimaging examples from the authors' institutional experience with the following conditions: the diversity of manifestations of common infections such as varicella zoster virus, Aspergillus, and progressive multifocal leukoencephalopathy (PML), drug therapy-related complications, stroke mechanisms, the spectrum of graft versus host disease (GVHD), and neurologically important syndromes of immune reconstitution inflammatory syndrome (IRIS), posterior reversible encephalopathy syndrome (PRES), and posttransplantation lymphoproliferative disorder (PTLD). These complications preferentially occur at specific intervals after HCT and SOT, and neurological consultants must recognize an extensive spectrum of syndromes in order to effect timely diagnosis and expedite appropriate treatment.