High rate of adenovirus detection in gastrointestinal biopsies of symptomatic stem cell transplant recipients.

OBJECTIVES: The gastrointestinal (GI) tract is a major human adenovirus (HAdV) replication site in patients undergoing hematopoietic stem cell transplantation (HSCT), yet the prevalence and correlates of HAdV GI infection in this setting have remained poorly recognized, especially among adult HSCT recipients. DESIGN OR METHODS: We retrospectively studied the prevalence and risk factors of HAdV GI-tissue infection in HSCT recipients (73 adults and 15 children) with GI symptoms who underwent GI-tissue biopsy between January-2012 and December-2017. The presence of HAdV in the GI tissues was determined by real-time PCR. RESULTS: HAdV GI-tissue infection was detected in 21 (23.9%) patients, with similar infection rates identified in adults and children. GI-tissue detection was more common at late (>100 days) compared to early times post-transplantation (50% vs. 12.9%, p < .001). The presence of bloody diarrhea, Arab ethnicity (p = .014) and concurrent cytomegalovirus GI-tissue detection (p = .025) were significantly correlated with HAdV GI-tissue infection, while chronic graft versus host disease was of borderline association (p = .055). CONCLUSIONS: Our findings reveal a high rate and new clinical-demographic correlates of HAdV GI-tissue infection in adult and pediatric HSCT recipients with GI symptoms. The findings highlight the need for future prospective studies to assess the relatedness of HAdV infection to the GI symptoms, and the prevalence, impact, and treatment of HAdV GI infection in HSCT recipients.

Adenoviral Penton and Hexon Proteins Are Equivalent Immunogenic Targets of Virus-Specific T Cells after Hematopoietic Stem Cell Transplantation in Children.

Human adenovirus (HAdV) infection is a serious complication that can lead to significant morbidity and mortality, especially in immunocompromised pediatric patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). Control and elimination of HAdV requires the presence of the respective antiviral T cells, and adoptive transfer of virus-specific T cells has become an important new treatment option for patients refractory to antiviral treatment. Although the adenoviral capsid protein hexon is known to be a major immunodominant T cell target across HAdV species, up to 30% of HAdV-seropositive donors show no T cell responses to the overlapping peptide pool spanning the entire protein. Our group recently verified the capsid protein penton as a second immunodominant target in HAdV infection. Here we aimed to investigate the prevalence of both penton-specific and hexon-specific HAdV T cells and their impact in virus control after HSCT. We analyzed the prevalence and characteristics of HAdV-specific T cells in 33 consecutive pediatric patients with HAdV reactivation following allogeneic HSCT and correlated them with viral load analysis. Our study demonstrates that penton is an important immunodominant target antigen of HAdV reactivation/ infection after HSCT in most patients. We demonstrate that in the majority of patients, both penton- and hexon-specific T cells appear at similar time intervals after transplantation. Despite the prevalence for either hexon-specific or penton-specific T cells in individual patients, we were unable to attribute the predominance to specific HLA types or HAdV serotypes. The occurrence of HAdV-specific T cells was closely linked to viral control, arguing for immune monitoring strategies to tailor antiviral treatment and adoptive T cell therapy.

[Clinical characteristics of patients with human adenovirus infection undergoing allogeneic hematopoietic stem cell transplantation].

Objective: To investigate the clinical characteristics and prognosis of human adenovirus (HAdV) infection in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods: This is a retrospective case series study. Patients who received allo-HSCT and had symptoms of HAdV infection were tested in the Hematology Department at Perking University People's Hospital from August 2015 to October 2019. Real-time quantitative PCR was used to detect HAdV DNA from 2 728 patients with potential infection. HAdV DNA-positive patients were defined as having HAdV infection. The clinical features of these patients were analyzed, and a case-pair method was used to select patients without HAdV infection as the control group in a 1∶3 ratio. The clinical results of the two groups were compared using Kaplan-Meier and Log-rank testing. Results: A total of 7 119 samples were tested for HAdV, of which 99 samples from 36 patients were positive. Of these patients, 22 developed HAdV viremia, and 24 patients had concurrent infection with another virus. Nineteen patients had fever (53%), 25 had gastrointestinal symptoms (69%), 11 had respiratory symptoms (31%), nine had reduced liver function (25%), and six had nervous system symptoms (17%). Twenty-three patients developed acute graft-versus-host disease of grade 2 or higher. Of all the patients with HAdV infection, nine were treated with cidofovir, seven of whom became HAdV negative and two had invalid treatment. The median follow-up time was 496 (216, 940) d post-HSCT. The overall survival at 5 years post HSCT was 48.4%±9.2% vs. 91.3%±3.5% (χ2=65.03, P<0.001) in patients with and without HADV, respectively. The non-relapse mortality at 5 years post-HSCT was 40.8%±8.8% vs. 4.0%±2.0% (χ2=34.17, P<0.001) in patients with and without HADV, respectively. Conclusions: After allo-HSCT, HAdV-infected patients are dominated by gastrointestinal and respiratory symptoms and have an increased risk of combined acute graft-versus-host disease of >2 degrees. Patients with HAdV infection have poor overall survival and high non-relapse mortality.

Adenovirus-36 as one of the causes of obesity: the review of the pathophysiology.

The dramatic increase of people affected by obesity worldwide seems to be influenced by external factors independent of eating habits, physical exercise, or genetic characteristics. There may be a number of such factors, but one hypothesis is that there is person-to-person transmission, causing an epidemic effect, as occurs with infectious diseases. In animal models, experimental infection with human adenovirus-36 (Adv36) causes obesity. Humans cannot be experimentally infected, but a number of studies found a correlation of positive serology for Adv36 with overweight/obesity in humans. In vitro studies have shown that Adv36 accelerates the differentiation and proliferation of preadipocytes into adipocytes and increases their lipid concentration. Another viral mechanism involved is the activation of a noninsulin-dependent process that increases glucose uptake, mainly in adipose tissue and muscle. The increased glucose, coupled with increased lipogenesis due to increased fatty acid synthase and the action of peroxisome proliferator-activated receptor gamma (PPAR-gamma) in stimulating adipocyte differentiation from adult stem cells enhances fat accumulation within the adipocytes. In studies conducted to date, the Adv36 E4 open reading frame 1 gene (E4orf1), which activates the glucose transporter protein isoform 4 (GLUT4) and glucose transporter protein isoform 1 (GLUT1) glucose transporters, appears to play a major role in the virus adipogenesis. The aim of this study was to review the pathophysiology of obesity and the role of Adv36.

Brincidofovir for the treatment of human adenovirus infection in pediatric solid organ transplant recipients: A case series.

HAdV viremia can cause significant morbidity among pediatric recipients of SOT with variability in incidence and severity of disease based on the type of allograft. Currently, there are no US FDA-approved treatments for HAdV infections, and historically, the mainstay of treatment has been decreasing immunosuppression, with antiviral therapies reserved for those with severe disease. We describe the treatment of four pediatric SOT recipients (two kidney, one combined kidney-liver, and one liver) presenting with HAdV disease at our institution using brincidofovir. Our case series highlights the variability in presentation and the potential for severe disease in pediatric SOT recipients as we review disease presentation, disease course, complications, and treatment with brincidofovir.

Disseminated adenovirus infection after autologous stem cell transplant.

Adenovirus is an infrequent but challenging viral complication of transplantation that is rarely reported after autologous stem cell transplant. We present a case of disseminated adenovirus infection in a woman who received an autologous stem cell transplant for treatment of multiple sclerosis. After presenting with post-transplant episodic diarrhea and viremia, endoscopic biopsies and immunohistochemical staining confirmed the diagnosis of disseminated adenovirus infection. Her symptoms and viremia resolved after treatment with cidofovir. This case demonstrates that a high index of suspicion, a systematic clinical approach, and immunohistochemical tissue staining are necessary to diagnose disseminated adenovirus infection in an unexpected host.

Transfer of Hexon- and Penton-selected adenovirus-specific T cells for refractory adenovirus infection after haploidentical stem cell transplantation.

Adenovirus (HAdV) infections confer a high risk of morbidity and mortality for immunocompromised patients after stem cell transplantation (SCT). Treatment with standard antiviral drugs is of limited efficacy and associated with a high rate of adverse effects. HAdV-specific T cells are crucial for sustained viral elimination and the efficacy of adoptive T-cell therapy with donor-derived HAdV-specific T cells has been reported by several investigators. Here, we report our experience with the transfer of HAdV-specific T cells specific for penton, which was recently identified as an immunodominant target of T cells, and hexon in a 14-year-old boy after T-cell-depleted haploidentical SCT for myelodysplastic syndrome (MDS). He developed severe HAdV-associated enteritis complicated by acute graft-versus-host disease (GvHD). The patient received ten infusions of allogeneic HAdV-specific T cells manufactured from the haploidentical stem cell donor using the CliniMacs Interferon-γ (IFN-γ) cytokine capture and immunomagnetic selection. Initially, T cells were generated against the immunodominant target hexon and in subsequent transfers dual antigen-specific T cells against hexon and penton were applied. T-cell transfers were scheduled individually tailored to current immunosuppressive treatment. Each transfer was followed by reduction of HAdV load in peripheral blood and clinical improvement. Importantly, T-cell responses to both penton and hexon pools emerged in patient blood after repetitive transfers. Unfortunately, the patient experienced bacterial sepsis, and in this context, severe GvHD requiring intensive immunosuppression followed by secondary progression of HAdV infection. The patient succumbed to multiorgan failure 283 days after SCT. This case demonstrates the feasibility of HAdV-specific T-cell transfer even in the presence of immunosuppressive treatment. Targeting of multiple immunodominant viral proteins may prove valuable in patients with complicated HAdV infections.

Comparative study of clinical and epidemiological characteristics of major pediatric adenovirus epidemics in southern Taiwan.

BACKGROUND: Human adenoviruses (HAdV) are important pathogens of pediatric respiratory tract infections in Taiwan. There were two major HAdV epidemics in southern Taiwan in 2011 and 2014, respectively. METHODS: The demographic, clinical characteristics, and risk factors for hospitalization of pediatric patients with HAdV infection in the two outbreaks were retrospectively compared. The epidemic was defined as > 7% HAdV detection rate for six consecutive weeks. HAdV infection was defined as positive HAdV isolates from respiratory tract specimens. HAdV genotype was determined by PCR-based hexon gene sequencing. RESULTS: A total of 1145 pediatric patients were identified (635 cases in 2011; 510 cases in 2014). HAdV genotype 3 and 7 contributed to both epidemics, although the proportion of HAdV3 decreased significantly (64.7% in 2011 to 25.5% in 2014, p < 0.001) and was replaced by other genotypes (type 1, 4, and 6) in the 2014 epidemic. Among the hospitalized patients, there were more patients hospitalized with bronchopneumonia/or pneumonia in the 2011 epidemic (10.6% vs 5.1%, p < 0.001), while more patients hospitalized with acute pharyngitis/pharyngoconjunctival fever (63.9% vs. 38.6%, p < 0.001) in the 2014 epidemic. In both epidemics, hospitalized patients had higher WBC and C-reactive protein (CRP) levels than non-hospitalized patients. Using multivariate regression analysis, underlying disease and elevated CRP levels were independent risk factors for hospitalization in both epidemics. CONCLUSION: There were significant differences in clinical, viral characteristics and risk factors of hospitalization between the 2011 and 2014 epidemics. Understanding changes in the epidemiological and clinical characteristics of HAdV epidemics is important from a public health perspective.

Infección respiratoria por adenovirus en pediatría: de ayer a hoy / Adenovirus pediatric respiratory infection: past and present

Acute respiratory infections represent a world pediatric health burden. RSV, influenza and adenoviruses are among the most frequent causative agents. Adenoviruses usually produce upper respiratory infections, but they can be responsible for acute lower respiratory infection in children with severe clinical outcome. It is necessary a special clinical and epidemiological organization to avoid nosocomial adenovirus local outbreaks. Rapid diagnose, done by immunofluorescence assay and PCR, individual case isolation and supportive therapy are necessary for an appropriate management. The increasing immune compromised population represents a challenge for the adenovirus diagnosis with quantitative PCR and for nosocomial infection control and potential antiviral treatment.

Las infecciones respiratorias agudas son un problema prioritario mundial de morbimortalidad infantil y son causadas predominantemente por virus, entre los que destacan el virus respiratorio sincicial (VRS), virus influenza (FLU) y adenovirus (ADV). Los ADV normalmente causan infecciones respiratorias altas, pero pueden provocar infecciones bajas muy graves, que dejan secuelas y tienen alta letalidad. Requieren un manejo clínico y epidemiológico especial para evitar los graves brotes nosocomiales observados en Latinoamérica. Esto incluye un diagnóstico rápido hecho con técnicas de inmunodiagnóstico y reacción en cadena polimerasa (PCR), aislamiento individual del paciente y terapia de soporte. En pacientes inmunocomprometidos, la infección por ADV representa un gran desafío para el diagnóstico, con uso de PCR cuantitativo (qPCR) y eventual tratamiento antiviral. El objetivo de esta revisión es el de actualizar las propiedades, patogenia, epidemiología y diagnóstico del ADV, con énfasis en los cuadros respiratorios de mayor morbimortalidad que se producen en algunos niños.

Strategies of adoptive T -cell transfer to treat refractory viral infections post allogeneic stem cell transplantation.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) can expose patients to a transient but marked immunosuppression, during which viral infections are an important cause of morbidity and mortality. Adoptive transfer of virus-specific T cells is an attractive approach to restore protective T -cell immunity in patients with refractory viral infections after allogeneic HSCT. OBJECTIVES: This narrative review summarizes clinical evidence and developments of almost 30 years of adoptive T -cell transfer. The review is based on evidence extracted from PubMed searches and the clinical and experimental work of the authors. CONTENT: Viral infections after HSCT are frequently caused by the endogenous reactivation of persistent pathogens such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus (AdV). Current antiviral medication is not satisfactory and does not treat the underlying pathophysiology which is the lack of specific T -cell immunity. Adoptive transfer of virus-specific T cells could be a potentially curative, pathogen-specific, and non-toxic treatment providing long-term immunity against the virus. The isolation of virus-specific T cells from a healthy donor and infusion into a recipient is known as adoptive T -cell transfer and has been performed in many patients using different treatment protocols. Based on basic research, new isolation protocols aim at a safe and fast availability of cellular products for adoptive T -cell transfer. We summarize preclinical and clinical data on each of the main pathogens and on the technical approaches currently available to target either single antigens or even multiple pathogens. CONCLUSION: Cellular therapy is considered as one of the major recent breakthroughs in medicine. Translation of this individualized treatment into first-line clinical routine is still limited. Main hurdles are availability of the technique, limited compatibility of classical phase III designs with cellular therapy, and regulatory restrictions. Multinational efforts are required to clarify the status of cellular treatment in first-line clinical routine with the overall objective to strengthen evidence-based treatment guidelines for the treatment of refractory viral infections post HSCT.

Clearance of Treatment Refractory Adenoviremia via Adenovirus-specific Donor T-Cell Transfer During Aplasia After αßTCR-CD19-Depleted Stem Cell Transplantation.

Here, we report the case of severe adenoviremia in a 7-year-old boy with highly-resistant, acute leukemia. A combined approach of αßTCR-CD19-depleted stem cell transplantation, enabling immunosuppression-free post-transplant care, and early transfer of adenovirus-specific donor T cells during aplasia resulted in rapid and complete clearance of the treatment-refractory adenoviremia.

HMGB1 mediates HAdV-7 infection-induced pulmonary inflammation in mice.

Human adenovirus (HAdV) is a common respiratory pathogen in children, with no safe and effective treatment currently available. HAdV type 7 (HAdV-7), in particular, causes severe pediatric pneumonia with a high incidence of sequelae and mortality. Clinical data and animal experiments suggest that HAdV-7-induced pneumonia promotes cell necrosis, releasing a large number of inflammatory mediators. In recent years, the high mobility group box-1 (HMGB1) protein, released by necrotic cells, has been shown to play important roles in several viral infections. Here, we show that HMGB1 levels gradually increased in the media supernatants of HAdV-7 infected A549 cells, starting at 12 h post-infection. In vivo, HMGB1 levels in BALF and mRNA levels in lung tissues significantly increased after 3 days of HAdV-7 infection. Among the HMGB1 receptor genes, TLR-4 and TLR-9 expression increased, and so did the receptor for advanced glycation end-products (RAGE). Interestingly, NF-κB levels also increased concomitantly. Conversely, when HMGB1 was blocked, the pathological scores from lung tissues, inflammatory mediator levels, and viral copy number all were reduced significantly; in addition, HMGB1-related signaling pathway molecules, namely TLR-4, TLR-9, RAGE, and NF-κB were also reduced. We conclude that HMGB1 promotes HAdV-7 replication and signals through TLR-4, TLR-9, and RAGE receptors to activate NF-κB, stimulating the release of inflammatory mediators and contributing to adenoviral pathology. Thus, HMGB1 could be used as a therapeutic target in HAdV-7 infection.

Adenovirus Infection in Children With Acute Myeloid Leukemia: A Report From the Canadian Infection in Acute Myeloid Leukemia Research Group.

BACKGROUND: Children with acute myeloid leukemia (AML) are at high risk of life-threatening bacterial and fungal infection. However, little is known about the prevalence or severity of adenovirus infection in this population. Objective was to describe the characteristics, treatments and outcomes of adenovirus infection in children with newly diagnosed AML. METHODS: We performed a retrospective chart review based upon 2 multicenter cohort studies that focused on identifying risk factors for infection in children with AML. Inclusion criteria were patients with de novo AML who were ≤18 years of age at diagnosis with a clinical specimen positive for adenovirus. RESULTS: Among the 235 patients with AML, 12 (5.1%) had positive adenovirus testing. The most common site of isolation was stool (n = 11, 91.6 %), and the most frequent symptom was diarrhea (n = 11, 91.6 %). Two patients received specific treatment for adenovirus, namely intravenous immunoglobulin only in 1 patient and both intravenous immunoglobulin and inhaled ribavirin in a second patient. In 11 patients, adenovirus resolved uneventfully without recurrence, including 10 that received no adenovirus-specific therapy. However, 1 patient developed sepsis syndrome in the setting of disseminated adenoviral infection and died from multiorgan failure. CONCLUSION: In children with AML, adenovirus infection was rare and typically not associated with severe disease, even without specific treatment. However, disseminated and fatal disease can occur in this population. Further investigations are needed to identify pediatric AML patients at particular risk for severe adenovirus infection and to determine optimal treatment approaches in these patients.

Adenoviral nephritis in a renal transplant recipient: Case report and literature review.

Adenovirus (AdV) infections in transplant recipients may cause invasive disease. We present a case of granulomatous interstitial nephritis secondary to AdV infection in a renal transplant recipient that was initially interpreted as acute graft rejection on histopathology. Specific testing based on clinical suspicion, however, aided in making an accurate diagnosis. We present a retrospective review of all cases of AdV infection in renal transplant recipients to date, and analyze outcomes based on different treatment modalities for this disease.

Epidemiology of Diarrheal Illness in Pediatric Oncology Patients.

BACKGROUND: Diarrhea is common in children with cancer, but this has not been systematically studied to date. METHODS: Remnant stool samples collected between January 2010 and June 2011 from pediatric oncology patients with diarrhea were tested for bacterial, viral, and parasitic enteropathogens using a combination of standard-of-care (SOC) diagnostic tests, including broad-range, real-time polymerase chain reaction (PCR) assays for adenoviruses, astroviruses, and sapoviruses and 2 commercially available multiplexed PCR assays. Corresponding demographic and clinical data were abstracted from patients' medical records. RESULTS: One hundred fourteen episodes of diarrhea in 93 patients (median age, 3.7 years; range, 0.2-18.8) were included in the study. No patients died, but morbidity was significant. A total of 158 potential pathogens were detected in 114 diarrhea episodes, with >1 organism in one third of these; the most common were Clostridium difficile, noroviruses, adenoviruses, and astroviruses. Clostridium difficile, in combination with norovirus or adenovirus, was most common when >1 pathogen was detected. When both studies were obtained, SOC and broadly multiplexed PCR tests were concordant in 64 episodes (56%). Forty-five pathogens (28%) were identified retrospectively by broadly multiplexed PCR assays only. A total of 19 (13%) were detected by SOC real-time PCR assays but not by either commercially available multiplexed PCR assay. CONCLUSIONS: Most pediatric oncology patients in this study had 1 or more potential infectious causes for their diarrhea. Additional studies are warranted to understand the natural history of gastroenteritis in this patient population. Although broadly multiplexed PCR assays offer some advantages over conventional testing, there may be disadvantages to their use for the diagnosis of infectious gastroenteritis that are unique to pediatric oncology patients.

Allograft biopsy findings in patients with small bowel transplantation.

In this study, we sought to determine the incidence of post-transplant complications including acute cellular rejection (ACR), infection, and post-transplant lymphoproliferative disease (PTLD) in mucosal allograft biopsies in patients with small bowel transplant at our institution. We retrospectively reviewed pathology reports from 5675 small bowel allograft biopsies from 99 patients and analyzed the following: indications for biopsy, frequency and grade of ACR, the presence of infectious agents, results of workup for potential PTLD, results of C4d immunohistochemistry (IHC), features of chronic mucosal injury, and findings in concurrent native bowel biopsies. Findings from 42 allograft resection specimens were also correlated with prior biopsy findings. Indeterminate, mild, moderate, and severe ACR were seen in 276 (4.9%), 409 (7.2%), 100 (1.8%), and 207 (3.6%) of biopsies, respectively. Although ACR may show histologic overlap with mycophenolate mofetil toxicity, we found the analysis of concurrent native bowel biopsies to be helpful in this distinction. Adenovirus was the most common infectious agent seen (11%), and we routinely performed adenovirus IHC on biopsies. Eighteen patients (18%) developed PTLD, 83% of which were EBV associated, but only 28% of PTLD cases were diagnosed on mucosal allograft biopsies. C4d IHC did not correlate with the presence of donor-specific antibodies in limited cases.

Infection-Related Death among Persons with Refractory Juvenile Idiopathic Arthritis.

Severe infections are emerging as major risk factors for death among children with juvenile idiopathic arthritis (JIA). In particular, children with refractory JIA treated with long-term, multiple, and often combined immunosuppressive and antiinflammatory agents, including the new biological disease-modifying antirheumatic drugs (DMARDs), are at increased risk for severe infections and death. We investigated 4 persons with JIA who died during 1994-2013, three of overwhelming central venous catheter-related bacterial sepsis caused by coagulase-negative Staphylococus or α-hemolytic Streptococcus infection and 1 of disseminated adenovirus and Epstein-Barr virus infection). All 4 had active JIA refractory to long-term therapy with multiple and combined conventional and biological DMARDs. Two died while receiving high-dose systemic corticosteroids, methotrexate, and after recent exposure to anti-tumor necrosis factor-α biological DMARDs, and 2 during hematopoietic stem cell transplantation procedure. Reporting all cases of severe infections and especially deaths in these children is of paramount importance for accurate surveillance.

Etiology and Incidence of Viral Acute Respiratory Infections Among Refugees Aged 5 Years and Older in Hagadera Camp, Dadaab, Kenya.

We used the Centers for Disease Control and Prevention-Kenya Medical Research Institute Acute Respiratory Infection (ARI) Surveillance System data to estimate severe acute respiratory infection (SARI) hospitalization rates, viral etiology, and associated complaints of influenza-like illnesses (ILI) and SARI conditions among those aged 5 years and older in Hagadera, Dadaab refugee camp, Kenya, for 2010-2012. A total of 471 patients aged ≥ 5 years met the case definition for ILI or SARI. SARI hospitalization rates per 10,000 person-years were 14.7 (95% confidence interval [CI] = 9.1, 22.2) for those aged 5-14 years; 3.4 (95% CI = 1.6, 7.2) for those aged 15-24 year; and 3.8 (95% CI = 1.6, 7.2) for those aged ≥ 25 years. Persons between the ages of 5 and 14 years had 3.5 greater odds to have been hospitalized as a result of SARI than those aged ≥ 25 years (odds ratio [OR] = 3.5, P < 0.001). Among the 419 samples tested, 169 (40.3%) were positive for one or more virus. Of those samples having viruses, 36.9% had influenza A; 29.9% had adenovirus; 20.2% had influenza B; and 14.4% had parainfluenza 1, 2, or 3. Muscle/joint pain was associated with influenza A (P = 0.002), whereas headache was associated with influenza B (P = 0.019). ARIs were responsible for a substantial disease burden in Hagadera camp.