Effective and less invasive diagnostic strategy for gastrointestinal GVHD

Unlocking the promise of mesenchymal stem cells and extracorporeal photopheresis to address rejection and graft failure in intestinal transplant recipients

INTRODUCTION

In patients with irreversible intestinal failure, intestinal transplant has become a standard treatment option. Graft failure secondary to acute or chronic cellular rejection continues to be a significant challenge following transplant. Even with optimal immune suppression, some patients continue to struggle with refractory rejection. Both extracorporeal photopheresis (ECP) and extracellular vesicles derived from mesenchymal stem cells (EVs) have been used to treat refractory rejection following intestinal transplantation, although their use remains limited and consistent treatment protocols are lacking.

METHODS

Intestinal transplant recipients who received ECP only or ECP and EVs as rescue therapy for acute cellular rejection or chronic inflammation between 2016 and 2022 were included in this single-center retrospective analysis. Baseline demographics, pre- and post-treatment histopathology, endoscopic and biochemical findings, and long-term transplant outcomes were analyzed.

RESULTS

Three patients (two pediatric and one adult) with acute steroid- and biologic-refractory rejection were treated with ECP and/or EVs, as was one patient (pediatric) with chronic graft rejection and inflammation. Patients received twice weekly ECP for 4 weeks and once weekly thereafter. EVs were administered in three doses each separated by 72 h. Immunosuppression at the time of treatment initiation included high-dose tacrolimus and sirolimus. Histologic resolution of rejection was achieved in all patients over 12-16 weeks. Steroids were weaned to low-dose or withdrawn in every patient within 4 weeks of ECP/EV treatment. C-reactive protein decreased from an average of 14.75 to 1.6 mg/dL post-treatment and fecal calprotectin decreased from average 800 mg/g to 31 mg/g. Donor-induced cytotoxic T cell populations were quantified for two of the patients with acute rejection, and in both cases decreased dramatically following treatment. There were no complications associated with either treatment.

CONCLUSION

Both ECP and EVs present novel opportunities to address graft rejection and inflammation in bowel transplant recipients. More work will be needed to define the optimal therapeutic parameters for each treatment modality.

Effective Extracorporeal Photopheresis of Patients with Transplantation Induced Acute Intestinal GvHD and Bronchiolitis Obliterans Syndrome

Background: Patients with steroid-refractory intestinal acute graft-versus-host disease (aGvHD) and bronchiolitis obliterans syndrome (BOS) represent a population with a high need for alternative and effective treatment options. Methods: We report real-life data from 18 patients treated with extracorporeal photopheresis (ECP). This cohort consisted of nine patients with steroid-refractory intestinal aGvHD and nine patients with BOS. Results: We document partial or complete clinical response and reduction of symptoms in half of the patients with intestinal acute GvHD and patients with BOS treated ECP. Responding patients tended to stay on treatment longer. In patients with BOS, stabilization of lung function and forced expiratory volume was observed, whereas, less abdominal pain, less diarrhea, and a reduction of systemic corticosteroids were seen in patients with intestinal acute GvHD. Conclusions: ECP might not only abrogate symptoms but also reduce mortality caused by complications from high-dose steroid treatment. Taken together, ECP offers a serious treatment avenue for patients with steroid-refractory intestinal acute GvHD and BOS.

Severe graft-versus-host disease-like enterocolitis accompanied with cytomegalovirus-reactivation in drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms

Drug-induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe drug adverse reaction with skin eruption and visceral organ involvement. The characteristic clinical features of DIHS/DRESS are reactivation of human herpesviruses (HHV) and the development of autoimmune diseases, but their pathogenesis and associations are not yet understood. Here, we report a 66-year-old man who presented with fever, generalized erythema, diffuse lymphadenopathy, and diarrhea after 3 weeks of treatment with zonisamide. Reactivation of HHV-6 and cytomegalovirus (CMV) was detected during the clinical course. The patient was diagnosed with DIHS/DRESS and treated with systemic prednisolone, i.v. immunoglobulin therapy, and ganciclovir. However, severe enterocolitis persisted for 6 months. A series of examinations revealed features of both CMV enterocolitis, as indicated by identification of a few CMV-positive cells on immunohistochemical analysis, and graft-versus-host disease (GVHD)-like enterocolitis indicated by orange-peel appearance on endoscopic examination and histopathological loss of goblet cells. Intractable enterocolitis continued and the patient finally died of pneumonia. An autoimmune predisposition in DIHS/DRESS patients in combination with CMV reactivation was considered to trigger the severe enterocolitis of this case that showed GVHD-like features of the gastrointestinal tract. GVHD-like organ damage is a pathological condition rarely observed in DIHS/DRESS but should be recognized as one of the most severe complications of the disease.

Observer agreement for the diagnosis of intestinal acute graft-vs.-host disease based on the presence of villous atrophy in the terminal ileum

Intestinal graft-vs.-host disease (GVHD) is a serious complication of allo-hematopoietic stem cell transplantation (allo-HSCT). Villous atrophy in the terminal ileum is considered a useful diagnostic indicator for GVHD. However, the inter- and intra-observer agreement regarding the ileocolonoscopic findings indicative of acute intestinal GVHD, i.e., villous atrophy in the terminal ileum, are currently insufficient in multiple institutions. Thus, the present study aimed to investigate the incidence of villous atrophy in the terminal ileum to diagnose acute intestinal GVHD and determine the inter- and intra-observer agreement regarding this result for experienced endoscopists from multiple institutions. Consecutive patients who underwent allo-HSCT were referred to our institution between May 2008 and September 2015. A total of 54 patients underwent total ileocolonoscopy after allo-HSCT due to suspected intestinal acute GVHD. Subsequently, three observers from different institutions evaluated the cases for the presence of villous atrophy in the terminal ileum. In this study, the pathology results were a gold standard to evaluate the predictive value of ileocolonoscopy detection. Definitive pathological and non-pathological GVHD was diagnosed in 22 and 32 cases, respectively. The results of examining whether villous atrophy could predict GVHD were as follows. For three observers (A, B and C), the sensitivity of villous atrophy in the terminal ileum was 86.4, 77.3 and 79.2%, respectively, whereas the specificity was 62.5, 62.5 and 86.7%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of villous atrophy for GVHD were as follows: The PPV of appearance was 61.3, 58.6 and 82.6%, respectively, whereas the NPV was 87.0, 80.0 and 83.9%, respectively. Kappa coefficients for the inter-observer reliability were 0.85, 0.63 and 0.63 for observers A and B, A and C, and B and C, respectively. The intra-observer kappa coefficient was 0.88 for observer A, 0.73 for observer B and 0.75 for observer C. A substantial observer agreement was achieved for the analysis of villous atrophy in the terminal ileum and the agreement for the predictive histological diagnosis was also excellent. Based on the results of the present study, identification of villous atrophy in the terminal ileum was a clinically effective diagnostic parameter, even if different endoscopists were involved in the diagnosis at multiple institutions. The present study was registered as a trial with the University Hospital Medical Information Network (UMIN; registration no. UMIN000025390).