Engraftment syndrome: a common cause for rash and fever following autologous hematopoietic stem cell transplantation for multiple sclerosis

Kidney Disease Following Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (SCT) provides a curative option for the treatment of several malignancies. Its growing use is associated with an increased burden of kidney disease. Acute kidney injury is usually seen within the first 100 days of transplantation and has an incidence ranging between 12 and 73%, with the highest rate in myeloablative allogeneic SCT. A large subset of patients after SCT develop chronic kidney disease. They can be broadly classified into thrombotic microangiopathy, nephrotic syndrome, and calcineurin toxicity. Dialysis requirement after SCT is associated with mortality exceeding 80%. Given the higher morbidity and mortality related to development kidney disease, nephrologists need to be aware of the various causes and best treatment options.

Endothelial Dysfunction after Hematopoietic Stem Cell Transplantation: A Review Based on Physiopathology

Endothelial dysfunction (ED) is frequently encountered in transplant medicine. ED is an argument of high complexity, and its understanding requires a wide spectrum of knowledge based on many fields of basic sciences such as molecular biology, immunology, and pathology. After hematopoietic stem cell transplantation (HSCT), ED participates in the pathogenesis of various complications such as sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), graft-versus-host disease (GVHD), transplant-associated thrombotic microangiopathy (TA-TMA), idiopathic pneumonia syndrome (IPS), capillary leak syndrome (CLS), and engraftment syndrome (ES). In the first part of the present manuscript, we briefly review some biological aspects of factors involved in ED: adhesion molecules, cytokines, Toll-like receptors, complement, angiopoietin-1, angiopoietin-2, thrombomodulin, high-mobility group B-1 protein, nitric oxide, glycocalyx, coagulation cascade. In the second part, we review the abnormalities of these factors found in the ED complications associated with HSCT. In the third part, a review of agents used in the treatment of ED after HSCT is presented.

Budesonide Prophylaxis Reduces the Risk of Engraftment Syndrome After Autologous Hematopoietic Cell Transplantation in Multiple Myeloma

BACKGROUND

Engraftment syndrome (ES) after autologous hematopoietic cell transplantation (AHCT) in multiple myeloma (MM) encompasses a continuum of periengraftment complications characterized by noninfectious fever, rash, diarrhea, and capillary leak features.

PATIENTS AND METHODS

We analyzed the ES outcomes in 257 consecutive patients MM patients who underwent AHCT at our institution from 12/2017 to 11/2019 with budesonide prophylaxis (3 mg PO daily at day +5 post-AHCT till the time of discharge) (N = 109) and no prophylaxis (N = 148).

RESULTS

The rates of ES were significantly higher in the no prophylaxis group versus prophylaxis group [69 (46%) vs. 23 (21%); P< .001]. There was no significant difference in length of stay (LOS) [mean 15 (±3.2) vs. 16 (±2.8); P = .27] and 30-day readmission [9 (6%) vs. 8 (7%); P = .81] between the no prophylaxis and prophylaxis groups, respectively. On adjusted analysis, budesonide prophylaxis was associated with a significantly lower risk of developing ES [odds ratio (OR) 0.29 (95% confidence interval [CI], 0.16-0.51); P< .0001]. There was no difference in the 30-day readmission rates [OR 1.12 (95% CI, 0.41-3.03); P = .81], but a trend for shorter LOS in the prophylaxis group [7.3% reduction in LOS (95% CI, -14.4% to 0%); P = .06].

CONCLUSION

Budesonide prophylaxis significantly reduces the risk of ES in MM patients undergoing AHCT. These promising results suggest the need for a randomized study investigate the role of budesonide for ES prophylaxis.

Prior anti-PD-1 therapy as a risk factor for life-threatening peri-engraftment respiratory distress syndrome in patients undergoing autologous stem cell transplantation

Peri-engraftment respiratory distress syndrome (PERDS) is a kind of potentially life-threatening complication of autologous stem cell transplantation (ASCT). PERDS is characterized by fever, dyspnea, and hypoxemia during neutrophil engraftment. In order to identify the high-risk factors for PERDS, we retrospectively analyzed 260 patients with lymphoma undergoing ASCT in recent five years. The conditioning regimen was BuCyE (busulfan, cyclophosphamide, and etoposide). There were 16 patients (6.1%) diagnosed as PERDS. In multivariate analysis, prior anti-programmed death-1 (PD-1) therapy (hazard ratio [HR] = 8.852, 95% confidence interval [CI]: 2.954-26.527, P < 0.001) and history of pulmonary disease (HR = 3.718, 95% CI: 1.197-11.545, P = 0.023) were independent risk factors for PERDS. Patients with prior anti-PD-1 therapy (n = 31) had higher incidence of engraftment syndrome (77.4% vs. 33.4%, P < 0.001), PERDS (25.8% vs. 3.5%, P < 0.001), and transplant-related mortality (9.7% vs. 0.4%, P < 0.001), compared with those without prior anti-PD-1 therapy (n = 229). Subgroup analysis showed that sintilimab seemed to be associated with higher incidence of PERDS (42.9% vs. 11.8%, P = 0.06) compared with non-sintilimab group (pembrolizumab or toripalimab). C-reactive protein might be a feasible early predictor for PERDS. In conclusion, our study suggests that prior anti-PD-1 therapy may be a strong risk factor for life-threatening PERDS in patients with lymphoma undergoing ASCT.

The induction strategies administered in the treatment of multiple myeloma exhibit a deleterious effect on the endothelium

Multiple myeloma induction treatment includes proteasome inhibitors (PI) and immunomodulatory agents at present. The incidence of engraftment syndrome, a transplant complication potentially related to endothelium, has increased in the last years. Our aim was to investigate whether bortezomib (Velcade, V), thalidomide (T), and dexamethasone (D) affect the endothelium, and explore defibrotide (DF) as protective agent. Endothelial cells (ECs) in culture were exposed to the compounds separately or in combination, without (VTD) and with DF (VTD + DF). Changes in markers of: (i) inflammation (ICAM-1 expression and leukocyte adhesion), (ii) VWF production, (iii) cell permeability (VE-cadherin expression and cell monolayer integrity), and (iv) oxidative stress (ROS production and eNOS expression) were measured. ICAM-1 and VWF expression increased significantly in VTD but were similar to controls in VTD + DF. Separately, bortezomib was the main deleterious agent whereas dexamethasone showed no harmful effect. Leukocyte adhesion showed similar trends. VE-cadherin expression was lower in VTD and normalized in VTD + DF. EC permeability increased only with bortezomib. No changes were observed in oxidative stress markers. Our results demonstrate that bortezomib damages the endothelium, and DF prevents this effect. A better knowledge of the induction drugs impact will allow the design of measures to protect the endothelium.

Dermatologic Conditions of the Early Post-Transplant Period in Hematopoietic Stem Cell Transplant Recipients

Hematopoietic stem cell transplants (HSCTs) are used to treat a variety of conditions, including hematologic malignancies, bone marrow failure syndromes, and immunodeficiencies. Over 60,000 HSCTs are performed annually worldwide, and the numbers continue to increase. Indeed, as new conditioning regimens develop, more and more individuals, including those of older age, will be eligible for transplants. Nevertheless, although HSCTs are clearly a life-saving and necessary treatment for thousands of patients per year, there is still substantial morbidity and mortality associated with the procedure. Of note, skin eruptions in the post-HSCT period are frequent and often significantly reduce quality of life in recipients. Moreover, these cutaneous findings sometimes herald an underlying systemic condition, presenting possible opportunities for timelier intervention. Dermatologists therefore play a vital role in distinguishing life-threatening conditions from benign issues and prompting recognition of critical complications earlier in their course. This article aims to review the major dermatologic conditions occurring in the early post-HSCT period.

Innovative strategies minimize engraftment syndrome in multiple myeloma patients with novel induction therapy following autologous hematopoietic stem cell transplantation

Autologous stem cell transplantation (PBSCT) is standard for young patients in MM and its TRM has decreased after the 2000s. Bortezomib and immunomodulatory agents (IMiDs) in MM have improved the outcome. However, they seem to boost pro-inflammatory stage increasing the incidence of engraftment syndrome (ES). Favorable factors in PBSCT such as G-CSF could increase inflammatory stage during transplant. Corticosteroids have shown an excellent response of ES and some authors propose them as prophylaxis for ES. The aim was to analyze the impact of G-CSF avoidance and corticosteroids' prophylaxis in 170 patients diagnosed of MM treated with bortezomib/IMiDs that underwent PBSCT. We established three groups: Group-I [(G-CSF_administration), 60 patients (35%)], group-II [(nonG-CSF), 60 patients (35%)] and group-III [(nonG-CSF plus corticosteroid's prophylaxis), 50 patients (30%)]. A decreased ES incidence among groups was observed: 62, 42, and 22% (P < 0.0001). The incidence of symptoms mimicking a capillary leak syndrome associated with ES dropped: 43, 32, and 0% (P = 0.03). The G-CSF avoidance and corticosteroids had impact over admission 24, 21, and 20 days (P = 0.001). The most important variables related to ES were HCT-CI >2 (p < 0.0001; HR 8.5) and risk groups (p < 0.0001; HR 7.2). Hence, G-CSF avoidance and corticosteroid's prophylaxis decrease morbidity in patients undergoing PBSCT with MM treated with bortezomib/IMiDs.

Engraftment syndrome after allogeneic hematopoietic cell transplantation in adults

We performed a retrospective study of the engraftment syndrome (ES) as defined by the Spitzer Criteria in adult patients undergoing allogeneic hematopoietic cell transplantation (HCT) for various hematological malignancies at a single institution, over a decade, and analyzed its relationship to acute GVHD; 217 patients underwent either myeloablative (38.7%) or reduced intensity (61.3%) HCT; 22.1% met the criteria for ES. Acute GVHD prophylaxis (P = 0.006) and transplants prior to 2006 (P < 0.0001) were significantly associated with a risk of ES in univariable analysis. Early aGVHD within 4 weeks of engraftment was significantly more common in the ES compared to the non ES cohort (21 vs. 8.3% respectively, P = 0.02). ES did not predict for future GVHD, as at day +180, the cumulative incidences of grades II-IV aGVHD (31 vs. 23%, P = 0.19) and of chronic GVHD at 2 years of engraftment (42 vs. 36%, P = 0.28) were not significantly different between the ES and non ES groups, respectively. No significant differences in NRM, overall survival and progression-free survival were observed between the two groups. Although predictive of early aGVHD, ES occurred independently of GVHD in 79% of the patients. Survival outcomes should be evaluated in a larger randomized study to investigate if there is a correlation with ES.

Haematopoietic SCT in severe autoimmune diseases: updated guidelines of the European Group for Blood and Marrow Transplantation

In 1997, the first consensus guidelines for haematopoietic SCT (HSCT) in autoimmune diseases (ADs) were published, while an international coordinated clinical programme was launched. These guidelines provided broad principles for the field over the following decade and were accompanied by comprehensive data collection in the European Group for Blood and Marrow Transplantation (EBMT) AD Registry. Subsequently, retrospective analyses and prospective phase I/II studies generated evidence to support the feasibility, safety and efficacy of HSCT in several types of severe, treatment-resistant ADs, which became the basis for larger-scale phase II and III studies. In parallel, there has also been an era of immense progress in biological therapy in ADs. The aim of this document is to provide revised and updated guidelines for both the current application and future development of HSCT in ADs in relation to the benefits, risks and health economic considerations of other modern treatments. Patient safety considerations are central to guidance on patient selection and HSCT procedural aspects within appropriately experienced and Joint Accreditation Committee of International Society for Cellular Therapy and EBMT accredited centres. A need for prospective interventional and non-interventional studies, where feasible, along with systematic data reporting, in accordance with EBMT policies and procedures, is emphasized.

Neurologic Complications of Bone Marrow and Stem-cell Transplantation in Patients with Cancer

Transplantation of bone marrow or peripheral blood stem cells is increasingly being used to treat a variety of oncologic disorders. These procedures are associated with a large spectrum of neurologic complications that significantly contribute to patient morbidity and mortality. These complications may arise at any time during and after the transplantation process and are particularly common in patients requiring chronic immunosuppression. The most frequent complications are infections and cerebrovascular or metabolic events, and toxicity from radiation or chemotherapy. Because of the unique circumstances and treatments involved in each step of the transplantation process, there is a higher incidence of some neurologic complications during discrete time periods, and an awareness of the temporal relationship of the neurologic disorder to the transplantation process facilitates diagnosis. With the exception of post-transplant lymphoproliferative disorder, in which reduced immunosuppression may be an effective therapeutic strategy, therapies are often the same as in the nontransplant patient. Complications of therapy can arise because of the presence of multiple comorbidities and medication interactions. Anticipation of common opportunistic infections and appropriate use of prophylactic medications can significantly reduce the incidence of infectious complications.

Hematopoietic SCT for the treatment of multiple sclerosis

Multiple sclerosis (MS) is the leading autoimmune indication for autologous hematopoietic SCT (aHSCT). Patient selection criteria and transplant interventions have been refined through a series of cohort and registry studies. High- and low-intensity chemotherapy-based conditioning regimens have been used, creating trade-offs between toxicity and effectiveness. TBI has been associated with greater toxicity and poor outcomes. aHSCT stops MS relapses and lessens the disability in malignant MS, which otherwise rapidly incapacitates patients. Better responses occur in progressive MS earlier in the disease when it has a more inflammatory nature. aHSCT prevents further disability in many patients, but some actually recover from their infirmities. Current regimens and supportive care result in very low morbidity and mortality. MS patients experience unique complications in addition to the expected toxicities. Cytokines used alone for stem-cell mobilization may induce MS flares but are safe to be used in combination with steroids or cytotoxic agents. Urinary tract infections, herpes virus reactivation and an engraftment syndrome may occur early after aHSCT. Rarely secondary autoimmune diseases have been reported late after HSCT. Increasing experience in caring for patients with MS has reduced the frequency and severity of toxicity. Conceived as an opportunity to 'reboot' a tolerant immune system, aHSCT is successful in treating patients with MS that is refractory to conventional immunomodulatory drugs.

Engraftment syndrome after auto-SCT: analysis of diagnostic criteria and risk factors in a large series from a single center

Engraftment syndrome (ES) is increasingly observed in patients who receive auto-SCT. To investigate this fact, validate the clinical criteria for ES diagnosis and analyze the risk factors for this complication, we reviewed 328 consecutive peripheral blood auto-SCT performed during the past 7 years. A total of 43 patients presented with clinical or biological data suggestive of ES. Of the total, 41 (95%) and 22 (51%) could be diagnosed with ES using the Maiolino criteria (MC) and the Spitzer criteria (SC), respectively. The SC were less sensitive as they do not consider some relevant clinical data and limit the observation time after engraftment. All ES cases had high C-reactive protein (CRP) values not observed in the remaining patients at engraftment (median +/- s.d.: 17.5 +/- 7.3 vs 2.4 +/- 3.4 mg per 100 ml; P=0.0001). Multivariate analysis showed a higher risk of ES in SCT performed in recent years (relative risk (RR) 2.3, 95% confidence interval (CI 1.0-4.7), female patients (RR 2.5, 95% CI 1.2-5.2), and absence of intensive chemotherapy before SCT (RR 8.8, 95% CI 3.3-20.5). All patients except one improved after treatment with corticosteroids. The MC seem to be the best tool to establish a diagnosis of ES. In doubtful cases, the diagnosis could be confirmed by evaluating CRP. Auto-SCT in patients not receiving previous chemotherapy could explain the increasing incidence of ES in the past years.

Engraftment syndrome following allogeneic hematopoietic stem cell transplantation in children

ES is a complication that occurs immediately before or at the timing of neutrophil engraftment following autologous or allogeneic SCT. It is characterized by fever, skin rash, and non-cardiac pulmonary infiltrates. We evaluated the incidence, risk factors, and outcomes of ES following allogeneic SCT in children. Of 100 pediatric patients, 20 (20%) developed ES occurring at a median of 14 days (range 8-27 days) post-transplant. Patients presented with fever (100%), skin rash (100%), diffuse pulmonary infiltration (25%), and body weight gain (85%). On multivariate analysis, significant risk factors for ES included younger age (<8 yr old) and human leukocyte antigen disparity between donors and recipients. Univariate analysis showed that patients with ES had a higher incidence of developing chronic graft-versus-host disease and ES was not associated with other complications. Event-free survival did not significantly differ between patients with and without ES regardless of the presence of malignant or non-malignant diseases.

Autologous and allogeneic hematopoietic stem cell transplantation for Multiple Sclerosis: perspective on mechanisms of action

Multiple Sclerosis (MS) is a frequent demyelinating immune-mediated disease of the central nervous system (CNS) that affects principally young adults and leads to severe physical and cognitive impairment. The current standard treatment makes use of the immune modulators beta-interferon, glatiramer acetate and natalizumab, or immunosuppressants such as mitoxantrone. However, these agents are only partially effective and in a number of patients fail to achieve satisfactory disease control. Autologous hematopoietic stem cell transplantation (HSCT) is being explored in the treatment of severe MS as a means of delivering high-dose immunosuppression followed by 'rescue' of the immuno-hematopoietic system with autologous HSC. The potential therapeutic benefit is based on the concept of so-called 'resetting' the immune system. The use of allogeneic HSCT as a possible therapeutic approach for severe MS is inspired by case reports of MS patients that underwent allogeneic HSCT for a concomitant hematological malignancy, and subsequently is supported by data from rodent models of MS. Allogeneic HSCT may offer specific therapeutic effects, such as the replacement of the autoreactive immune compartment by healthy allogeneic cells and the development of a graft-versus-autoimmunity (GVA) effect. Here, we review the currently available experimental and clinical evidence to support the role of autologous and allogeneic HSCT in MS.

Incidence, predisposing factors, and outcome of engraftment syndrome in pediatric allogeneic stem cell transplant recipients

Engraftment syndrome (ES) has been recognized as an inflammatory condition during neutrophil recovery after hematopoietic stem cell transplantation (HSCT) characterized by noninfectious fever and skin rash. It has been reported to occur frequently after autologous HSCT in children and adults, and has been shown to be an independent risk factor for increased transplant-related mortality (TRM). However, virtually no data exist on its occurrence after allogeneic HSCT in children. To determine incidence, predisposing factors for, and complications of ES in a pediatric transplant cohort, we analyzed 61 consecutive recipients of a myeloablative allogeneic HSCT for the occurrence of ES. Diagnosis of ES was established when children presented with > or =2 of the following symptoms within 7 days before engraftment: (1) fever >38.0 degrees C, (2) skin rash, (3) weight gain and albumin drop, or (4) dyspnea, hypoxia, and pulmonary infiltrates. Incidence of ES in this cohort was 48% (29 of 61). In a univariate analysis, posttransplant granulocyte-colony stimulating factor (G-CSF) administration (P = .02), and high mononuclear cell count (MNC) (P = .002) were identified as significant risk factors predisposing for the development of ES. In a multiple logistic regression analysis, amphotericin B therapy (P = .009) and high MNC (P = .004) were significant explanatory variables for ES risk. There was a slight trend toward a higher rate of chronic GVHD (cGVHD) in patients with ES (P = .11). However, after a median follow-up of 9.5 years overall survival (OS) (P = .53) and TRM (P = .65) did not differ between the 2 groups. ES presenting with fever, rash, weight gain, and pulmonary symptoms should be recognized as a frequent complication of allogeneic HSCT after myeloablative conditioning in children. Treatment with G-CSF, amphotericin B, and a high nucleated cell count of the graft predisposed for the development of ES in this study. OS and TRM in this cohort were not affected by the occurrence of ES.

Autologous non-myeloablative hematopoietic stem cell transplantation in patients with systemic sclerosis

Autologous hematopoietic stem cell transplantation (HSCT) utilizing a myeloablative regimen containing total body irradiation has been performed in patients with systemic sclerosis (SSc), but with substantial toxicity. We, therefore, conducted a phase I non-myeloablative autologous HSCT study in 10 patients with SSc and poor prognostic features. PBSC were mobilized with CY and G-CSF. The PBSC graft was cryopreserved without manipulation and re-infused after the patient was treated with a non-myeloablative conditioning regimen of 200 mg/kg CY and 7.5 mg/kg rabbit antithymocyte globulin. There was a statistically significant improvement of modified Rodnan skin score whereas cardiac (ejection fraction, pulmonary arterial pressure), pulmonary function (DLCO) and renal function (creatinine) remained stable without significant change. One patient with advanced disease died 2 years after the transplant from progressive disease. After median follow-up of 25.5 months, the overall and progression-free survival rates are 90 and 70% respectively. Autologous HSCT utilizing a non-myeloablative conditioning regimen appears to result in improved skin flexibility similar to a myeloablative TBI containing regimen, but without the toxicity and risks associated with TBI.

Autologous Haematopoietic Stem Cell Transplantation for the Treatment of Multiple Sclerosis

Introduction: Autologous haematopoietic stem cell transplantation (auto-HSCT) has been performed for severe multiple sclerosis (MS) refractory to standard therapy with increasing frequency worldwide. However, experience in Asia employing this modality in MS has been limited. In this review, we explored the pathophysiology of autoimmunity and the underlying rationale for auto-HSCT in treating autoimmune diseases including MS, as well as existing published pre-clinical and clinical data. We aimed thereby to better understand the utility of treating MS with auto-HSCT and the feasibility of this procedure in Singapore. Methods: A Medline search was performed with the terms “haematopoietic stem cell transplantation”, “multiple sclerosis” and “autoimmune diseases” from 1996 to 2005. Both original papers and review articles were considered. Main Findings: The majority of publications were from Europe or the United States and most clinical series from single centres had relatively small numbers of patients. Worldwide, the number of patients reported has been less than 300 since 1997. Existing data support the feasibility and promise of this procedure and ongoing Phase III trials may serve to confirm this initial experience. Conclusion: Pre-clinical and early clinical data support the rationale for immunoablative therapy for autoimmune disorders. Auto-HSCT for severe MS is a feasible procedure and can be safely performed in centres with experience managing HSCT patients. Key words: Autoimmunity, Induction of tolerance, Progressive multiple sclerosis

Neurologic complications of bone marrow, stem cell, and organ transplantation in patients with cancer

Bone marrow and peripheral blood stem cell transplantation are part of the standard of care for a variety of oncologic and non-oncologic disorders and are associated with a large spectrum of neurologic complications. These complications may arise at any time during and after the transplantation process, especially in subjects requiring chronic immunosuppression, and are most frequently related to infections, cerebrovascular or metabolic events, and toxicity from radiation or chemotherapy. Due to the unique circumstances and treatments surrounding each step in the transplantation process, there is a higher incidence of some neurologic complications during discrete time periods. Being aware of the temporal relationship of the neurologic disorder within the transplantation process can therefore facilitate diagnosis and institution of appropriate therapy. Neurologic complications after solid organ transplantation are often due to similar mechanisms as in patients after bone marrow and stem cell transplantation although there are several complications unique to these patients such as transmission of infectious agents by the donated organ. For these patients, the clinician needs to have a high index of suspicion that the neurologic problem is related to the transplant.

Engraftment syndrome after nonmyeloablative allogeneic hematopoietic stem cell transplantation: incidence and effects on survival

Engraftment syndrome (ES) encompasses a constellation of symptoms that occur during neutrophil recovery after both autologous and allogeneic hematopoietic stem cell transplantation (HCT). Although it is well characterized after conventional myeloablative procedures, limited data exist on this complication after nonmyeloablative allogeneic HCT. The clinical manifestations, incidence, and risk factors associated with ES were investigated in a consecutive series of patients undergoing cyclophosphamide/fludarabine-based nonmyeloablative allogeneic HCT from a related HLA-compatible donor. Fifteen (10%) of 149 patients (median age, 53 years; range, 27-66 years) developed ES; the onset of symptoms occurred at a median of 10 days (range, 3-14 days), and they consisted of fever (100%), cough (53%), diffuse pulmonary infiltrates (100%), rash (13%), and room air hypoxia (87%). ES was more likely to develop in patients who received empiric amphotericin formulations after transplant conditioning (Fisher exact test; P=.007). In a multivariate analysis, older patient age, female sex, and treatment with amphotericin were predictors for the development of ES. Intravenous methylprednisolone led to the rapid resolution of ES; however, transplant-related mortality was significantly higher (cumulative incidence, 49% versus 16%; P=.0005), and median survival was significantly shorter (168 versus 418 days; P=.005) in patients with ES compared with non-ES patients. In conclusion, ES occurs commonly after cyclophosphamide/fludarabine-based nonmyeloablative transplantation and responds rapidly to corticosteroid treatment, but it is associated with a higher risk of nonrelapse mortality and with shorter overall survival.

Haemopoietic stem cell transplantation in autoimmune diseases: a European perspective

The potential of haemopoietic stem cell transplantation (HSCT) for the treatment of autoimmune and inflammatory diseases was originally supported by almost three decades of animal experiments and by the serendipitous remissions of autoimmune disease observed in patients undergoing transplantation for haematological disorders. Improved safety of both autologous and allogeneic HSCT over the last decade has been followed by increasing acceptance of HSCT as an experimental treatment for severe autoimmune diseases that are resistant to conventional treatment. International databases have collated over 700 procedures performed specifically for a variety of autoimmune diseases. Phase III clinical trials are in progress for some diseases. This review provides a comprehensive update on the efficacy and toxicity of HSCT in severe autoimmune disease. Future directions in the context of other evolving therapies are discussed.

Autologous haematopoietic-stem-cell transplantation for multiple sclerosis

Intense immunosuppression followed by autologous haematopoietic-stem-cell transplantation (HSCT) is being assessed as a potential treatment for patients with severe multiple sclerosis (MS). The treatment was developed from research that showed autologous HSCT was as effective as allogeneic HSCT in the treatment of experimental autoimmune encephalomyelitis. The treatment is thought to eradicate the defective immune system, and the infused haematopoietic stem cells reconstitute an immune system that is more tolerant to the nervous system. About 250 patients with MS have been treated with autologous HSCT as part of phase I and phase II open trials. Autologous HSCT seems feasible in MS and assessment with clinical and MRI measures suggests it induces a profound and long-lasting suppression of inflammation. The course of MS seems to be stabilised after autologous HSCT, especially in ambulatory patients with evidence of active disease. Autologous HSCT deserves further study in randomised controlled trials.

Steroids prevent engraftment syndrome after autologous hematopoietic stem cell transplantation without increasing the risk of infection

Engraftment syndrome (ES) following autologous hematopoietic stem cell transplantation (AHSCT) is characterized by fever and rash. In January 2002, we instituted steroid prophylaxis for ES from day +4 to +14. This study was conducted to assess whether this practice increased the risk of infection. In total, 194 consecutive patients were reviewed, 111 did not receive steroid prophylaxis (group A), and 83 did (group B). Initial antimicrobial prophylaxis was the same in both groups. There were no significant differences between groups in age, gender, race, prior radiation therapy, number of prior chemotherapy regimens, disease status at transplant, mobilization regimen, days of leukopheresis, CD34(+) cell dose, and days to platelet and neutrophil engraftment. Group B had significantly fewer patients with non-Hodgkin's lymphoma and multiple myeloma, shorter median duration from diagnosis to transplant, lower risk of ES, and shorter mean length of hospital stay. The incidence of early and late microbiologically confirmed infections was not significantly different between groups. Types of infections and types of organisms identified were similar in both groups. Hospital readmission rates were similar in both groups. Steroid prophylaxis significantly decreases the risk of ES following AHSCT, and is associated with shortened hospitalization, without increasing risk of infection.

Haematopoietic stem cell transplantation for autoimmune disorders: the American perspective

The hypothesis that haematopoietic stem cell transplantation (HSCT) might be useful in treating refractory autoimmune diseases (AID) was suggested by studies in animal models and by the improvement of concurrent autoimmune diseases in patients who had undergone transplantation for haematological disorders. This concept has now been tested in a substantial number of phase I/II clinical trials of autologous HSCT. These early results are promising, even in patients who have failed on multiple standard therapies for AID. Transplantation-related toxicity has decreased with growing experience in the application of this procedure, better patient selection and the modification of treatment protocols. Randomized trials currently under way or under consideration should clarify the role of HSCT in patients with autoimmune disorders.

A rare case of interstitial pneumonitis after tandem high-dose melphalan conditioning and autologous stem cell transplantation in multiple myeloma

A 57-yr-old woman with multiple myeloma received an autologous tandem transplant at a 4-month interval. She was conditioned twice with 225 mg/m2 melphalan. After the second transplant, interstitial pneumonitis (IP) ensued. The clinical course was life threatening and mechanical ventilation was required for 32 d. All attempts to identify an infectious agent failed. A presumptive diagnosis of idiopathic IP, possibly related to melphalan toxicity, was made. High-dose methylprednisolone administration led to rapid and durable improvement. Melphalan was employed for conditioning in the tandem setting with an interval of only 3-4 months between two courses or a dose elevation to 225 instead of 200 mg/m2, may have induced IP which responded favorably to methylprednisolone.

Hematopoietic stem cell transplantation for progressive multiple sclerosis: failure of a total body irradiation-based conditioning regimen to prevent disease progression in patients with high disability scores

There were 21 patients with rapidly progressive multiple sclerosis (MS) treated on a phase 1/2 study of intense immune suppressive therapy and autologous hematopoietic stem cell (HSC) support with no 1-year mortality. Following transplantation, one patient had a confirmed acute attack of MS. Neurologic progression defined by the expanded disability status scale (EDSS) did not increase in disability by 1.0 or more steps in any of 9 patients with a pretransplantation EDSS of 6.0 or less. In 8 of 12 patients with high pretransplantation disability scores (EDSS > 6.0), progressive neurologic disability as defined by at least a 1-point increase in the EDSS has occurred and was manifested as gradual neurologic deterioration. There were 2 patients with a pretransplantation EDSS of 7.0 and 8.0 who died from complications of progressive disease at 13 and 18 months following treatment. Our experience suggests that intense immune suppression using a total body irradiation (TBI)-based regimen and hematopoietic stem cell transplantation (HSCT) are not effective for patients with progressive disease and high pretransplantation disability scores. Further studies are necessary to determine the role of intense immune suppressive therapy and HSC support in ambulatory patients with less accumulated disability and more inflammatory disease activity. Specifically, more patients and longer follow-up would be required in patients with an EDSS of 6.0 or less before drawing conclusions on this subgroup.

The promise of hematopoietic stem cell transplantation for autoimmune diseases

Hematopoietic stem cell transplantation (HSCT) is being increasingly utilized for the treatment of a whole spectrum of severe autoimmune diseases refractory to conventional therapy. Although allogeneic HSCT has been followed by durable complete remission in a restricted number of patients with coincidental disease, the autologous procedure is generally preferred because of its lesser toxicity. Most autoimmune diseases are the consequence of a multistep process, mainly originating from the interplay of genetic, environmental, and hormonal factors. It has been postulated that if immunosuppressive regimens can eliminate or effectively reduce the level of autoreactive T and B cells, then regeneration of de novo immunity even in the autologous setting may bypass the initial breakdown of self-tolerance and ensure prolonged disease remission. As mentioned in a recent review of this field, protocol design including conditioning regimen, patient selection, stem cell source and final outcome are likely to be disease-specific. The following is a summary of the 2002 International Bone Marrow Transplantation Registry/American Society of Blood and Bone Marrow Transplantation (IBMTR/ASBMT) satellite symposium in Orlando, Florida on 24 February 2002 on 'Expanding the Promise of Hematopoietic Stem Cell Transplantation in Autoimmune Diseases'.