Autoimmune complications after hematopoietic stem cell transplantation in children with nonmalignant disorders

Characterizing the cutaneous late effects of allogeneic hematopoietic stem cell transplantation: A systematic review

BACKGROUND

There is a well-documented risk of secondary cutaneous malignancies following allogeneic hematopoietic stem cell transplant (HSCT), but data on risk in pediatric populations are limited. The objective of this study is to perform a systematic review of reported features and outcomes of skin cancers in pediatric allogeneic HSCT recipients.

METHODS

MEDLINE, EMBASE, CINAHL, Cochrane, and Web of Science were systematically searched (Prospero CRD42022342139). Studies reporting cutaneous cancer outcomes were included if the age at transplant was ≤19 years. Titles, abstracts, and full-text articles were screened in duplicate.

RESULTS

Out of 824 citations that were screened, 12 articles were selected for analysis. The final sample included 67 pediatric HSCT recipients, comprising 65 allogeneic transplant recipients and 2 cases of HSCT with an unknown donor type. The median age at transplant and skin cancer diagnosis were 7.4 and 13 years, respectively. Out of the 67 pediatric HSCT recipients, some patients developed more than one lesion, resulting in 71 lesions. The most common skin cancer type was cutaneous squamous cell carcinoma (32 lesions), followed by basal cell carcinoma (25 lesions). The median latency period between HSCT and skin cancer diagnosis ranged from 0 to 29 years. Identified risk factors for skin cancers included younger age at the time of transplant, exposure to total body irradiation, prolonged post-transplant immunosuppression, graft versus host disease, and sunburn.

CONCLUSION

Skin cancers are reported in pediatric allogeneic HSCT recipients, and the risk appears to be increased. More data are needed to better characterize this risk.

Cytoplasmic Antineutrophil Cytoplasmic Antibodies (C-ANCA) Vasculitis: An Uncommon Complication After Stem Cell Transplantation

Granulomatosis with polyangiitis (GPA) is a rare, autoimmune, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis of uncertain etiology. The incidence of autoimmune complications following stem cell transplant is around 2-5%, with autoimmune cytopenia reported most frequently. We present a case of a 65-year-old male patient who presented to the hospital with productive cough, dyspnea, and fever for five months after haploidentical stem cell transplantation. On presentation, he was febrile, tachypneic, and mildly hypoxic. Chest radiograph showed bilateral pulmonary infiltrates. An initial diagnosis of pneumonia was made, and the patient was started on antibiotics. The patient did not respond to initial management, and all his initial infectious workups came back negative. On further evaluation, cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA) resulted positive in high titers. The patient was diagnosed with GPA, and IV methylprednisolone and rituximab were started. He responded well to treatment and was eventually discharged home. The classical form of GPA is characterized by the involvement of the upper respiratory tract, sinuses, lungs, and kidneys. Autoimmune disorders may develop secondary to hematopoietic stem cell transplant (HSCT). In our case, the patient was diagnosed with GPA, which is likely one of the autoimmune complications after HSCT.

Targeting plasma cells with daratumumab aids in the treatment of post-transplant autoimmune-like hepatitis

Antibody-mediated autoimmune-like hepatitis is a rare and challenging occurrence after hematopoietic cell transplant (HCT). We present the case of a 16-year-old male patient with Ph+ ALL who underwent matched sibling donor HCT and developed autoimmune-like hepatitis after receiving ponatinib for post-HCT maintenance, evidenced by marked plasma cell infiltrate on liver biopsy. He was successfully treated with steroids and daratumumab, an anti-CD38-monoclonal antibody. The dramatic response in this patient warrants expanded investigation of daratumumab for plasma cell-mediated disorders post-HCT. It further highlights that identifying mechanisms of immune-mediated injury can allow for directed therapy and limit exposure to broad immune suppression.

Characterizing Immune-Mediated Cytopenias After Allogeneic Hematopoietic Cell Transplantation for Pediatric Nonmalignant Disorders

Immune-mediated cytopenias (IMC)-isolated or combined hemolytic anemia, thrombocytopenia, or neutropenia-are increasingly recognized as serious complications after allogeneic hematopoietic cell transplantation (HCT) for nonmalignant disorders (NMD). However, IMC incidence, duration, response to therapy, and risk factors are not well defined. This retrospective chart review identified cases of IMC with serologic confirmation among patients who underwent HCT for NMD at a single institution between 2010 and 2017. IMC after HCT for NMD in a large pediatric cohort (n = 271) was common with a cumulative incidence of 18%, identified at a median of 136 days after HCT. Treatment included prolonged immune suppression (>3 months) in 58% of all IMC cases, 91% when multiple cell lines were affected. Multiple therapeutic agents were used for the majority affected, and median time to resolution of IMC was 118 days from diagnosis. Fine-Gray competing risk multivariate regression analysis identified a combined risk factor of younger age (<3 years) and inherited metabolic disorder, as well as hemoglobinopathy (at any age) associated with 1-year incidence of IMC (P < .01). We expand these findings with the observation of declining donor T-lymphoid chimerism from day 60 to 100 and lower absolute CD4+ counts at day 100 (P < .01), before median onset of IMC, for patients with IMC compared to those without. In this cohort, 4 deaths (8%) were associated with IMC, including 2 requiring second transplantation for secondary graft failure. Although the pathogenesis of IMC post-HCT for NMD remains elusive, further research may identify approaches to prevent and better treat this HCT complication.

Vitiligo: An Updated Narrative Review

BACKGROUND

Vitiligo is a relatively common acquired pigmentation disorder that can cause significant psychological stress and stigmatism.

OBJECTIVE

This article aims to familiarize physicians with the clinical manifestations, evaluation, diagnosis, and management of vitiligo.

METHODS

A Pubmed search was conducted in Clinical Queries using the key term "vitiligo". The search included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to English language. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Approximately one quarter of patients with vitiligo have the onset before 10 years of age. Genetic, immunological, neurogenic and environmental factors may have a role to play in the pathogenesis. Vitiligo typically presents as acquired depigmented, well-demarcated macules/patches that appear milk- or chalk-white in color. Lesions tend to increase in number and enlarge centrifugally in size with time. Sites of predilection include the face, followed by the neck, lower limbs, trunk, and upper limbs. The clinical course is generally unpredictable. In children with fair skin, no active treatment is usually necessary other than the use of sunscreens and camouflage cosmetics. If treatment is preferred for cosmesis, topical corticosteroids, topical calcineurin inhibitors, and narrowband ultraviolet B phototherapy are the mainstays of treatment.

CONCLUSION

The therapeutic effect of all the treatment modalities varies considerably from individual to individual. As such, treatment must be individualized. In general, the best treatment response is seen in younger patients, recent disease onset, darker skin types, and head and neck lesions. Topical corticosteroids and calcineurin inhibitors are the treatment choice for those with localized disease. Topical calcineurin inhibitors are generally preferred for lesions on genitalia, intertriginous areas, face, and neck. Narrowband ultraviolet B phototherapy should be considered in patients who have widespread vitiligo or those with localized vitiligo associated with a significant impact on the quality of life who do not respond to treatment with topical corticosteroids and calcineurin inhibitors.

AT1R Activating Autoantibodies in Hematopoietic Stem Cell Transplantation

Angiotensin II type 1 receptor activating autoantibodies (AT1R-AAs) have gained attention in solid organ transplant as non-HLA antibodies associated with rejection, vasculopathy, and graft dysfunction. These antibodies have also been reported in the context of pre-eclampsia, scleroderma, and isolated hypertension. Here, we present 3 post-hematopoietic stem cell transplant (HSCT) cases with patients demonstrating elevated levels of AT1R-AAs detected within the first year post-HSCT. All patients had hypertension, and 2 patients exhibited profound diarrhea and hypokalemia. The hypertension, in all cases, was refractory to multiple classes of antihypertensives. Upon autoantibody identification, an angiotensin receptor blocker, losartan, was promptly initiated, and all patients showed blood pressure improvement. The 2 patients with electrolyte disturbances had rapid normalization of these levels and resolution of the diarrhea. These cases demonstrate a previously unreported association of elevated AT1R-AA levels in post-HSCT patients with a rapid response to angiotensin receptor blockade initiation.

Autoimmune cytopenias following allogeneic hematopoietic stem cell transplant in pediatric patients: Response to therapy and late effects

BACKGROUND

Autoimmune cytopenias (AICs) are rare, but serious complications of allogeneic hematopoietic cell transplantation (allo-HSCT).

PROCEDURE

We performed a case-control study using 20 pediatric AIC cases and 40 controls, matched by stem cell source and primary indication comparing clinical and transplant characteristics, treatment, outcomes, and late effects.

RESULTS

Cases were more likely to be human leukocyte antigen mismatched (P = 0.04). There was no difference in conditioning regimen, serotherapy use, graft-versus-host disease (GVHD) prophylaxis, incidence of acute or chronic GVHD, ABO compatibility, infections, and donor engraftment. The median time to AIC onset was 219 days (range, 97-1205 days) and AIC resolution was 365 days (range, 10 days to 2737.5 days). First-line therapies for AIC patients most commonly included corticosteroids (75%) and rituximab (55%). Only 25% of patients responded to first-line treatment. At a median of 611.5 days from last rituximab dose, 82.5% patients were still receiving intravenous immune globulin for hypogammaglobulinemia compared with 2.5% of controls (P < 0.0001). Iron overload was higher in AIC patients (P = 0.0004), as was avascular necrosis (P = 0.04). There was no difference in overall survival at one year after HSCT (85% vs 82.5%). Two patients with refractory autoimmune hemolytic anemia responded to daratumumab and had resolution of B-cell aplasia.

CONCLUSIONS

In this study, we find poor initial responses to AIC-directed therapies and significant late effects.

Autoimmunity Following Allogeneic Hematopoietic Stem Cell Transplantation

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

Autoimmune Cytopenias Developing Late Post Alemtuzumab-Based Allogeneic Stem Cell Transplantation: Presentation of Short Case Series from a Transplant Center

Stem cell transplantation remains the curative option for many patients with hematological malignancies. The long-term effects of these treatments on the patients and their immune systems have been extensively investigated, but there remains a paucity of data regarding autoimmune manifestations post-transplant, although these effects are well recognized.

Herein we present the clinical picture and therapeutic approach in three patients (cases 1–3), with varied presentations of autoimmune disease post-transplant. Case 1 exhibited autoimmune hemolytic anemia and other autoimmune manifestations (serositis, thyroiditis), that were probably linked to graft versus relapsed leukemia effect. Cases 2 and 3 had pure red white cell aplasia and pure red cell aplasia, respectively, which were associated with hyperglobulinemia and a clonal T cell expansion.

Successful long-term outcome after combined hematopoietic stem cell transplantation and small bowel transplantation: A case report and review of the literature

Combining HSCT with SOT is an unusual and challenging undertaking given the complexities of immune modulation, the need to balance comorbidities, and the cumulative potential for complications. Early life-threatening complications include infections and related effects, graft rejection, and GVHD can be expected to be increased especially if the HSCT is indicated for high-risk cases such as individuals with severe combined immune deficiency and SOT that includes an intestine graft. Herein, we report such a case. Our patient is unique as a long-term survivor. We review the literature and the features of our case, especially the timing of transplants and human leukocyte antigen matching for HSCT that resulted in a successful outcome and discuss how this may be applied to others in the future.

Vitiligo following stem-cell transplant

Vitiligo is an acquired skin disorder characterised by depigmentation of skin due to the selective destruction of melanocytes. The pathogenesis of vitiligo is still relatively unknown, but associations between vitiligo and other systemic autoimmune diseases have been made, such as with patients who have undergone haematopoietic stem cell transplantation (HSCT) in the treatment of haematological conditions. This article aims to review published literature that have reported the incidence of vitiligo following HSCT in order to understand their relationship, and any potential connections between vitiligo and graft-versus-host disease (GVHD). On the 21st of May 2017, the databases Pubmed, EMBASE and SCOPUS were searched using the search terms Stem cell or transplant or GVHD AND vitiligo or leucoderma or leucoderma. There was a total of 38 cases (from 28 case report articles) along with 9 cohort studies that were included in the review. The studies reviewed showed that the incidence of vitiligo in patients who have received HSCT is higher than that of the normal population. Current studies are largely limited to single-case reports, which have certain inconsistencies with regard to patient/donor profiling, and future studies should look to address these issues.

Autoimmune hemolytic anemia and immune thrombocytopenia following hematopoietic stem cell transplant: A critical review of the literature

Autoimmune cytopenias (AIC) post-hematopoietic stem cell transplant (HSCT) are rare but exceptionally challenging complication. We conducted a comprehensive literature review and identified a pooled incidence of post-HSCT autoimmune hemolytic anemia and/or immune thrombocytopenia of 2.66% (SE = 0.27) in pediatric patients. Nonmalignant disease, unrelated donor transplant, peripheral or cord blood stem cell source, conditioning regimen without total body irradiation, and presence of chronic graft-versus-host disease were prominent risk factors. Treatment was highly variable, and cytopenias were commonly refractory. AIC represent a significant post-HSCT complication. We report here the incidence, risk factors, and possible biology behind the development of AIC in pediatric post-HSCT patients.

Autoimmune Cytopenias in Pediatric Hematopoietic Cell Transplant Patients

Background: Autoimmune cytopenias (AICs) are potentially life-threatening complications following hematopoietic cell transplantation (HCT), yet little is understood about the mechanism by which they develop. We hypothesized that discordant B cell and T cell recovery is associated with AICs in transplant patients, and that this might differ based on transplant indication. Methods: In this case control study of children who underwent HCT at our institution, we evaluated the clinical and transplant characteristics of subjects who developed AICs compared to a control group matched by transplant indication and donor type. In cases, we analyzed the state of immune reconstitution, including B cell recovery, T cell recovery, and chimerism, immediately prior to AIC onset. Subjects were stratified by primary indication for transplant as malignancy (n = 7), primary immune deficiency (PID, n = 9) or other non-malignant disease (n = 4). We then described the treatment and outcomes for 20 subjects who developed AICs. Results: In our cohort, cases were older than controls, were more likely to receive a myeloablative conditioning regimen and had a significantly lower prevalence of chronic GVHD. There were distinct differences in the state of immune recovery based on transplant indication. None of the patients (0/7) transplanted for primary malignancy had T cell recovery at AIC onset compared to 71% (5/7) of patients with PID and 33% (1/3) of patients with non-malignant disease. The subset of patients with PID and non-malignant disease who achieved T cell reconstitution (6/6) prior to AIC onset, all demonstrated mixed or split chimerism. Subjects with AIHA or multi-lineage cytopenias had particularly refractory courses with poor treatment response to IVIG, steroids, and rituximab. Conclusions: These results highlight the heterogeneity of AICs in this population and suggest that multiple mechanisms may contribute to the development of post-transplant AICs. Patients with full donor chimerism may have early B cell recovery without proper T cell regulation, while patients with mixed or split donor chimerism may have residual host B or plasma cells making antibodies against donor blood cells. A prospective, multi-center trial is needed to develop personalized treatment approaches that target the immune dysregulation present and improve outcomes in patients with post-transplant AICs.

Autoimmune thyroiditis following HLA-matched sibling hematopoietic stem cell transplantation for Wiskott-Aldrich syndrome

WAS is a fatal X-linked combined immunodeficiency syndrome, the only cures for which are HSCT or gene therapy. AID occur in up to 72% of patients with WAS who do not receive HSCT, likely arising secondary to impaired multilineage immune autoregulatory function; AITD is not typically seen. In this article, we describe the case of a male patient who underwent HLA-matched HSCT for WAS at the age of 5 months, with his sister (a WAS carrier) acting as his donor and subsequently developed AITD 12 months post-transplant, with marked elevation of antithyroid peroxidase antibody titer. His donor sister was subsequently found to have elevated antithyroid peroxidase antibody titer with increasing trend and normal thyroid function. Although several mechanisms exist by which our patient may have developed AITD, we suggest the transfer of autoreactive donor immune cells as the most plausible explanation.

Adrenal crisis in a 14-year-old boy 12 years after hematopoietic stem cell transplantation

We report on a boy of Albanian descent with the history of juvenile myelomonocytic leukemia (JMML). JMML was diagnosed at the age of 17 months and treated by hematopoietic stem cell transplantation (HSCT). At the age of 14.3 years, about 12 years after HSCT, he was hospitalized with an adrenal crisis. Hormone findings were consistent with primary adrenal insufficiency. Autoimmune adrenalitis was confirmed by positive autoantibodies against 21-hydroxylase and adrenal tissue. Since autoimmune Hashimoto thyroiditis was already known from the age of 9 years, we assume that both diseases are part of the spectrum of autoimmune polyglandular syndrome (APS) type 2. APS type 2 is a rare endocrine disease characterized by Addison’s disease along with autoimmune thyroid disease and/or type 1 diabetes.

HSCT-GAVE as a Manifestation of Chronic Graft versus Host Disease: A Case Report and Review of the Existing Literature

Gastric antral vascular ectasia or “watermelon stomach” is a significant cause of nonvariceal upper GI bleeding and is characterized by red, tortuous ectatic vessels along longitudinal folds in the gastric antrum. The existing literature links GAVE to patients with cirrhosis, scleroderma, bone marrow transplantation, and chronic renal failure among other associations, but its pathophysiology remains ill-defined. Over 30 cases of hematopoietic stem cell transplant-related GAVE (HSCT-GAVE) have been reported in the literature to date and there are likely many more that go undiagnosed or are attributed to another cause of upper gastrointestinal bleeding. Interestingly, a busulfan-containing conditioning regimen has been the primary factor implicated in the etiology of HSCT-GAVE because this was common to all cases in the literature to date. Here, we present the first case of HSCT-GAVE in a patient that was treated with a non-busulfan-containing conditioning regimen. We propose a link between chronic GVHD and the development of HSCT-GAVE that is supported by a similar development of GAVE in patients with systemic sclerosis.

Current approaches in biomaterial-based hematopoietic stem cell niches

Hematopoietic stem cells (HSCs) are multipotent progenitor cells that can differentiate and replenish blood and immune cells. While there is a growing demand for autologous and allogeneic HSC transplantation owing to the increasing incidence of hereditary and hematologic diseases, the low population of HSCs in cord-blood and bone marrow (the main source of HSCs) hinders their medical applicability. Several cytokine and growth factor-based methods have been developed to expand the HSCs in vitro; however, the expansion rate is low, or the expanded cells fail to survive upon engraftment. This is at least in part because the overly simplistic polystyrene culture substrates fail to fully replicate the microenvironments or niches where these stem cells live. Bone marrow niches are multi-dimensional, complex systems that involve both biochemical (cells, growth factors, and cytokines) and physiochemical (stiffness, O₂ concentration, and extracellular matrix presentation) factors that regulate the quiescence, proliferation, activation, and differentiation of the HSCs. Although several studies have been conducted on in vitro HSC expansion via 2D and 3D biomaterial-based platforms, additional work is required to engineer an effective biomaterial platform that mimics bone marrow niches. In this study, the factors that regulate the HSC in vivo were explained and their applications in the engineering of a bone marrow biomaterial-based platform were discussed. In addition, current approaches, challenges, and the future direction of a biomaterial-based culture and expansion of the HSC were examined.

STATEMENT OF SIGNIFICANCE

Hematopoietic stem cells (HSC) are multipotent cells that can differentiate and replace the blood and immune cells of the body. However, in vivo, there is a low population of these cells, and thus their use in biotherapeutic and medical applications is limited (i.e., bone marrow transplantation). In this review, the biochemical factors (growth factors, cytokines, co-existing cells, ECM, gas concentrations, and differential gene expression) that may regulate the over-all fate of HSC, in vivo, were summarized and discussed. Moreover, different conventional and recent biomaterial platforms were reviewed, and their potential in generating a biomaterial-based, BM niche-mimicking platform for the efficient growth and expansion of clinically relevant HSCs in-vitro, was discussed.

Autoimmune-Like Hepatitis

A 59-year-old female received a matched related donor stem cell transplant for chronic myelogenous leukemia. After being successfully treated with prednisone for chronic graft versus host disease that initially started 50 days posttransplant, she developed hepatic dysfunction during the steroid taper on day 531, as evidenced by jaundice, elevated liver enzymes, and increased bilirubin. Liver biopsy showed histology suggestive of autoimmune-like hepatitis, which is a rare manifestation of chronic “hepatitic” graft versus host disease.