Haploidentical hematopoietic stem cell transplantation for pediatric patients with chronic active Epstein-Barr virus infection: a retrospective analysis of a single center

Diagnostic performance of a multiplexed gastrointestinal PCR panel for identifying diarrheal pathogens in children undergoing hematopoietic stem cell transplant

BACKGROUND

Diarrhea is a common complication of hematopoietic stem cell transplantation (HSCT) and is associated with substantial morbidity, but its etiology is often unknown. Etiologies of diarrhea in this population include infectious causes, chemotherapy- or medication-induced mucosal injury and graft-versus-host disease (GVHD). Distinguishing these potential causes of diarrhea is challenging since diarrheal symptoms are often multifactorial, and the etiologies often overlap in transplant patients. The objectives of this study were to evaluate whether the FilmArray gastrointestinal (GI) panel would increase diagnostic yield and the degree to which pre-transplantation colonization predicts post-transplantation infection.

METHODS

From November 2019 to February 2021, a total of 158 patients undergoing HSCT were prospectively included in the study. Stool specimens were obtained from all HSCT recipients prior to conditioning therapy, 28 ± 7 days after transplantation and at any new episode of diarrhea. All stool samples were tested by the FilmArray GI panel and other clinical microbiological assays.

RESULTS

The primary cause of post-transplantation diarrhea was infection (57/84, 67.86%), followed by medication (38/84, 45.24%) and GVHD (21/84, 25.00%). Ninety-five of 158 patients were colonized with at least one gastrointestinal pathogen before conditioning therapy, and the incidence of infectious diarrhea was significantly higher in colonized patients (47/95, 49.47%) than in non-colonized patients (10/63, 15.87%) (P < 0.001). Fourteen of 19 (73.68%) patients who were initially colonized with norovirus pre-transplantation developed a post-transplantation norovirus infection. Twenty-four of 62 (38.71%) patients colonized with Clostridium difficile developed a diarrheal infection. In addition, FilmArray GI panel testing improved the diagnostic yield by almost twofold in our study (55/92, 59.78% vs. 30/92, 32.61%).

CONCLUSIONS

Our data show that more than half of pediatric patients who were admitted for HSCT were colonized with various gastrointestinal pathogens, and more than one-third of these pathogens were associated with post-transplantation diarrhea. In addition, the FilmArray GI panel can increase the detection rate of diarrheal pathogens in pediatric HSCT patients, but the panel needs to be optimized for pathogen species, and further studies assessing its clinical impact and cost-effectiveness in this specific patient population are also needed.

Updated guidelines for chronic active Epstein-Barr virus disease

Chronic active Epstein-Barr virus disease (CAEBV), formerly named chronic active Epstein-Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein-Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000 IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

Clinical Analysis of Chronic Active Epstein-Barr Virus Infection Involving the Gastrointestinal Tract

BACKGROUND

Chronic active Epstein‒Barr virus infection (CAEBV) is an intractable and progressive disease. T cells or NK cells infected by EBV can proliferate and infiltrate into multiple organs. CAEBV combined with gastrointestinal involvement is a rare clinical disease that has not been well described, and sometimes it may clinically mimic gastroenteritis or inflammatory bowel disease.

METHODS

This was an observational study that included all pediatric CAEBV patients who were treated at Beijing Children's Hospital, Capital Medical University, from June 2017 to June 2021. Patients were divided into the case group and the control group according to whether these patients had GI involvement. The children's clinical manifestations, laboratory and ultrasound examinations, treatment and prognosis were observed.

RESULTS

Seventy-two patients were enrolled in this study. Fifteen patients had GI involvement, including 11 males and 4 females, accounting for 20.8%, with a median onset age of 3.71 (0.64-14.47) years. The most common clinical manifestation at onset was diarrhea (13/15). Gastrointestinal ultrasound showed pneumatosis intestinalis, mild to moderate swelling of the surrounding mesentery and omentum and enhancement on ultrasound. The endoscopic features were hyperemia, edema and ulcers of variable morphological characteristics. Pathological examination showed lymphocyte infiltration with EBV-encoded small RNA (+), and the common locations of involvement were the colon (n = 6) and gastric antrum (n=3). The median follow-up time was 13.26 (0.31-51.89) months. Ten patients survived, and 5 patients died (including 1 who died of intestinal perforation because of necrotizing enterocolitis). Compared with the control group, the case group had higher alanine aminotransferase levels, aspartate aminotransferase and whole blood EBV-DNA copies (P = 0.038, 0.040 and < 0.001) and lower natural killer cell activity (P < 0.001). The 3-year overall survival rate of the case group was significantly lower than that of the control group (59.3% ± 12.9% vs. 79.4% ± 4.9%, P = 0.021).

CONCLUSION

The incidence of CAEBV with GI involvement was low. The most common location of involvement was the colon. CAEBV with GI involvement had a poor prognosis. Patients with high whole blood EBV-DNA copy levels early in their illness were more likely to develop GI involvement.

Massive pericardial effusion due to chronic active Epstein-Barr virus infection successfully treated with PD-1 blockade: A case report

RATIONALE

Chronic active Epstein-Barr virus (EBV) infection (CAEBV) is a rare but life-threatening EBV-positive lymphoproliferative disorder. Currently, treatment options for CAEBV are limited. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only way to cure CAEBV. Here, we report a rare case of CAEBV manifesting as massive pericardial effusion that was successfully treated with programmed cell death protein-1 (PD-1) blockade immunotherapy.

PATIENT CONCERNS

A 36-year-old woman with intermittent chest distress and dyspnea for 8 months was admitted to our center on October 25, 2021. Laboratory tests showed leukocytopenia and elevated liver enzyme levels. Initial echocardiography revealed massive pericardial effusion.

DIAGNOSIS

High levels of EBV-DNA were detected in the pericardial fluid by metagenomic next-generation sequencing. The pathological diagnosis of her left inguinal lymph node and skin lesions revealed systemic CAEBV.

INTERVENTIONS

The patient received sintilimab injection at a dose of 200 mg every 2 weeks in combined with lenalidomide 10 mg once daily.

OUTCOMES

The patient achieved complete resolution of pericardial effusion 5 months after PD-1 blockade immunotherapy without apparent adverse effects.

LESSONS

CAEBV is a rare but life-threatening EBV-positive lymphoproliferative disease. We present a rare case of massive pericardial effusion caused by systemic CAEBV, which was successfully treated with sintilimab. This case highlights the promising curative effect of PD-1 blockade immunotherapy in systemic CAEBV, especially for patients not suitable for allo-HSCT.