Coreactivation of Human Herpesvirus 6 and Cytomegalovirus Is Associated With Worse Clinical Outcome in Critically Ill Adults

Coinfection of Dermal Fibroblasts by Human Cytomegalovirus and Human Herpesvirus 6 Can Boost the Expression of Fibrosis-Associated MicroRNAs

Tissue fibrosis can affect every type of tissue or organ, often leading to organ malfunction; however, the mechanisms involved in this process are not yet clarified. A role has been hypothesized for Human Cytomegalovirus (HCMV) and Human Herpesvirus 6 (HHV-6) infections as triggers of systemic sclerosis (SSc), a severe autoimmune disease causing progressive tissue fibrosis, since both viruses and antiviral immune responses toward them have been detected in patients. Moreover, HCMV or HHV-6A infection was reported to increase the expression of fibrosis-associated transcriptional factors and miRNAs in human dermal fibroblasts. However, it is unlikely that they have separate effects in the infected host, as both viruses are highly prevalent in the human population. Thus, our study aimed to investigate, by quantitative real-time PCR microarray, the impact of HCMV/HHV-6A coinfection on the expression of pro-fibrotic miRNAs in coinfected cells, compared to the effect of single viruses. The results showed a possible synergistic effect of the two viruses on pro-fibrotic miRNA expression, thus suggesting that HCMV and HHV-6 may enhance each other and cooperate at inducing enhanced miRNA-driven fibrosis. These data may also suggest a possible use of virus-induced miRNAs as novel diagnostic or prognostic biomarkers for SSc and its clinical treatment.

The application of metagenomic next-generation sequencing for detection of pathogens from dialysis effluent in peritoneal dialysis-associated peritonitis

BACKGROUND

Metagenomic next-generation sequencing (mNGS) can improve pathogen identification in infectious diseases.

METHODS

A prospective parallel control study was undertaken to evaluate the clinical significance of mNGS in identifying pathogens in dialysis effluent of patients with peritoneal dialysis-associated peritonitis (peritonitis). Dialysis effluent specimens were detected both by peritoneal dialysis effluent culture and mNGS. The positive rates and coincidence rates of the two methods were compared.

RESULTS

From April 2020 to March 2021, 30 patients presenting with peritonitis were enrolled in this study. The positive pathogen detection rate of mNGS was significantly higher than that of the traditional culture method (86.67% vs. 60.00%; p = 0.039). Fifteen specimens were positive for both of the methods, while 11 specimens were negative for culture but positive for mNGS. Three specimens were positive for culture but negative for mNGS; all of them were streptococcus mitis. One specimen was negative for both methods. The culture method detected one type of pathogen in all specimens; however, two or more types of pathogens were detected in eight specimens by mNGS. In addition to common pathogens, additional pathogens detected by mNGS included Coxiella burnetii, human herpesvirus type 5, human herpesvirus type 6B and Mortierella.

CONCLUSION

The pathogen detection rate of mNGS in dialysis effluent of peritonitis patients was significantly higher than that of traditional culture. The mNGS is advantageous in diagnosing the pathogens that are difficult to be cultured. However, mNGS did not demonstrate sensitivity to streptococcus mitis. Results from this study show that mNGS, combined with traditional culture, has potential application for detecting pathogens in peritoneal dialysis patients with peritonitis.

Human Cytomegalovirus and Human Herpesvirus 6 Coinfection of Dermal Fibroblasts Enhances the Pro-Inflammatory Pathway Predisposing to Fibrosis: The Possible Impact on Systemic Sclerosis

Systemic sclerosis (SSc) is a severe autoimmune disease likely triggered by genetic and environmental factors, including viral infections. Human cytomegalovirus (HCMV) and human herpesvirus 6A species (HHV-6A) have been associated with SSc, based on in vivo and in vitro evidence, but the data are still inconclusive. Furthermore, despite both viruses being highly prevalent in humans and able to exacerbate each other’s effects, no data are available on their joint effects. Hence, we aimed to study their simultaneous impact on the expression of cell factors correlated with fibrosis and apoptosis in in vitro coinfected fibroblasts, representing the main target cell type in SSc. The results, obtained by a microarray detecting 84 fibrosis/apoptosis-associated factors, indicated that coinfected cells underwent higher and more sustained expression of fibrosis-associated parameters compared with single-infected cells. Thus, the data, for the first time, suggest that HCMV and HHV-6A may cooperate in inducing alterations potentially leading to cell fibrosis, thus further supporting their joint role in SSc. However, further work is required to definitively answer whether β-herpesviruses are causally linked to the disease and to enable the possible use of targeted antiviral treatments to improve clinical outcomes.

Comparative clinical manifestations and immune effects of cytomegalovirus infections following distinct types of immunosuppression

BACKGROUND

Cytomegalovirus (CMV) infection is a well-recognized complication of solid organ and hematopoietic cell transplantation. However, CMV infection also occurs in patients with human immunodeficiency virus (HIV) infection, previously immunocompetent intensive care unit (ICU) patients, and individuals on immunosuppressive medications for various underlying diseases.

OBJECTIVES

This review describes the comparative effects of CMV infection in distinct types of acquired immunosuppression.

SOURCES

Selected peer-reviewed publications on CMV infections published until December 2021.

CONTENT

CMV infection affects various organ systems through direct cytolytic mechanisms, but may also exert indirect effects by promoting pro-inflammatory and immunosuppressive responses. This has been well studied in transplant recipients, for whom antiviral prophylaxis and pre-emptive therapy have now become standard practice. These strategies not only prevent direct CMV disease manifestations, but also mitigate various immunopathological processes to reduce graft-versus-host disease, graft rejection, and the occurrence of secondary bacterial and fungal infections. The efficacy of neither prophylactic nor pre-emptive treatment of CMV infection has been demonstrated for patients with critical illness- or medication-induced immunosuppression. Many observational studies have shown an independent association between CMV reactivation and a prolonged duration of mechanical ventilation or increased mortality in the ICU. Furthermore, data suggest that CMV reactivation may increase pulmonary inflammation and prolong the duration of mechanical ventilation.

IMPLICATIONS

A large number of observational and experimental studies suggest attributable morbidity and mortality related to CMV infection, not only in transplant recipients and patients with HIV infection but also in patients with critically illness- or medication-induced immunosuppression. Adequately powered randomized controlled trials investigating the efficacy of prophylaxis or pre-emptive treatment of CMV infection in these patients are lacking, with a notable exception for transplant recipients.

Herpesviruses in Critically Ill Patients With ARDS

Reactivation of herpsviruses, mainly HSV, CMV and EBV, are frequent among critically ill patients. Although they are not immunocompromised from a classical point of view, these patients often present an alteration of their immune system favoring viral reactivation. Seropositive patients with sepsis and under mechanical ventilation are particularly at risk. Herpesviruses have a pulmonary tropism and can be responsible for non-resolving forms of acute respiratory distress syndrome with high mortality. However, the direct causality between herpesviruses reactivation and impaired outcomes among severely ill patients remains under debate.

Understanding the interaction between cytomegalovirus and tuberculosis in children: The way forward

Over 1 million children develop tuberculosis (TB) each year, with a quarter dying. Multiple factors impact the risk of a child being exposed to Mycobacterium tuberculosis (Mtb), the risk of progressing to TB disease, and the risk of dying. However, an emerging body of evidence suggests that coinfection with cytomegalovirus (CMV), a ubiquitous herpes virus, impacts the host response to Mtb, potentially influencing the probability of disease progression, type of TB disease, performance of TB diagnostics, and disease outcome. It is also likely that infection with Mtb impacts CMV pathogenesis. Our current understanding of the burden of these 2 diseases in children, their immunological interactions, and the clinical consequence of coinfection is incomplete. It is also unclear how potential interventions might affect disease progression and outcome for TB or CMV. This article reviews the epidemiological, clinical, and immunological literature on CMV and TB in children and explores how the 2 pathogens interact, while also considering the impact of HIV on this relationship. It outlines areas of research uncertainty and makes practical suggestions as to potential studies that might address these gaps. Current research is hampered by inconsistent definitions, study designs, and laboratory practices, and more consistency and collaboration between researchers would lead to greater clarity. The ambitious targets outlined in the World Health Organization End TB Strategy will only be met through a better understanding of all aspects of child TB, including the substantial impact of coinfections.

Herpes DNAemia and TTV Viraemia in Intensive Care Unit Critically Ill Patients: A Single-Centre Prospective Longitudinal Study

Introduction

We analysed blood DNAemia of TTV and four herpesviruses (CMV, EBV, HHV6, and HSV-1) in the REAnimation Low Immune Status Marker (REALISM) cohort of critically ill patients who had presented with either sepsis, burns, severe trauma, or major surgery. The aim was to identify common features related to virus and injury-associated pathologies and specific features linking one or several viruses to a particular pathological context.

Methods

Overall and individual viral DNAemia were measured over a month using quantitative PCR assays from the 377 patients in the REALISM cohort. These patients were characterised by clinical outcomes [severity scores, mortality, Intensive Care Unit (ICU)-acquired infection (IAI)] and 48 parameters defining their host response after injury (cell populations, immune functional assays, and biomarkers). Association between viraemic event and clinical outcomes or immune markers was assessed using χ²-test or exact Fisher’s test for qualitative variables and Wilcoxon test for continuous variables.

Results

The cumulative incidence of viral DNAemia increased from below 4% at ICU admission to 35% for each herpesvirus during the first month. EBV, HSV1, HHV6, and CMV were detected in 18%, 12%, 10%, and 9% of patients, respectively. The incidence of high TTV viraemia (>10,000 copies/ml) increased from 11% to 15% during the same period. Herpesvirus viraemia was associated with severity at admission; CMV and HHV6 viraemia correlated with mortality during the first week and over the month. The presence of individual herpesvirus during the first month was significantly associated (p < 0.001) with the occurrence of IAI, whilst herpesvirus DNAemia coupled with high TTV viraemia during the very first week was associated with IAI. Herpesvirus viraemia was associated with a lasting exacerbated host immune response, with concurrent profound immune suppression and hyper inflammation, and delayed return to immune homeostasis. The percentage of patients presenting with herpesvirus DNAemia was significantly higher in sepsis than in all other groups. Primary infection in the hospital and high IL10 levels might favour EBV and CMV reactivation.

Conclusion

In this cohort of ICU patients, phenotypic differences were observed between TTV and herpesviruses DNAemia. The higher prevalence of herpesvirus DNAemia in sepsis hints at further studies that may enable a better in vivo understanding of host determinants of herpesvirus viral reactivation. Furthermore, our data suggest that EBV and TTV may be useful as additional markers to predict clinical deterioration in ICU patients.

Association of HHV-6 With Outcomes in CMV-seronegative Liver Transplant Recipients With CMV-seropositive Donors Receiving Preemptive Antiviral Therapy

BACKGROUND

Risk factors, virological parameters, and outcomes associated with HHV-6 viremia in high-risk donor CMV-seropositive and recipient CMV-seronegative (D+R-) liver transplant recipients in the current era are incompletely defined.

METHODS

The study population consisted of patients in the preemptive therapy (PET) arm of a randomized, controlled trial of PET versus valganciclovir prophylaxis for CMV prevention in D+R- liver transplant recipients. Weekly blood samples through 100 d in the PET group were tested for HHV-6 viremia using a real-time quantitative polymerase chain reaction. Assessments included virological characteristics and relationship with CMV, risk factors, and impact of HHV-6 viremia with outcomes through 12 mo posttransplant.

RESULTS

HHV-6 viremia at any level developed in 42% (40 of 96). Older patient age (P = 0.03), longer hospitalization (P = 0.015), and ICU stay at transplantation (P = 0.029) were significantly associated with high-grade viremia. Concurrent HHV-6 and CMV viremia was associated with earlier onset of HHV-6 viremia (P = 0.004), higher HHV-6 area under the curve (P = 0.043), and higher peak HHV-6 viral load (P = 0.006) versus HHV-6 viremia alone. High-grade viremia was independently associated with biopsy-proven rejection within 12 mo (P = 0.045) posttransplant.

CONCLUSIONS

Among D+R- liver transplant recipients receiving valganciclovir as PET, high-grade HHV-6 viremia was associated with increased age and critical illness in ICU at time of transplant and was independently associated with allograft rejection.

Herpesviridae in critically ill hematology patients: HHV-6 is associated with worse clinical outcome

PURPOSE

Although viral infections are frequent among patients with hematological malignancies (HM), data about herpesviridae in critically ill hematology patients are scarce. We aimed at determining the impact of herpesviridae reactivation/infection in this population.

MATERIAL AND METHODS

We performed a single center retrospective study including all consecutive adult hematology patients admitted to our comprehensive cancer center ICU on a 6-year period. Clinical characteristics, microbiological findings, especially virus detection and outcome were recorded.

RESULTS

Among the 364 included patients, HHV-6 was the predominant retrieved herpesviridae (66 patients, 17.9%), followed by HSV1/2 (41 patients, 11.3%), CMV (38 patients, 10.4%), EBV (24 patients, 6.6%) and VZV (3 patients). By multivariable analysis, HHV-6 reactivation was independently associated with hospital mortality (OR, 2.35; 95% CI, 1.03-5.34; P = 0.042), whereas antiviral prophylaxis during ICU stay had a protective effect (OR, 0.41; 95% CI, 0.18-0.95; P = 0.037). HHV-6 pneumonitis was independently associated with 1-year mortality (OR, 6.87; 95% CI, 1.09-43.3; P = 0.04).

CONCLUSIONS

Among critically ill hematology patients, HHV-6 reactivation and pneumonitis are independent risk factors for hospital and 1-year mortality, respectively. Impact of prevention and treatment using agents active against HHV-6 should be assessed to define a consensual diagnostic and therapeutic strategy.

Frequent co-reactivation of Epstein-Barr virus in patients with cytomegalovirus viremia under immunosuppressive therapy and/or chemotherapy

Objective

Co-reactivation of cytomegalovirus (CMV) and Epstein–Barr virus (EBV) occurs in iatrogenically immunosuppressed patients, but the clinical relevance of this is unknown. We aimed to determine the frequency of EBV reactivation in patients with CMV viremia and to explore its clinical significance.

Methods

Serum or plasma CMV and EBV DNA was detected by quantitative real-time PCR in 82 patients who received immunosuppressive therapy and/or chemotherapy and underwent CMV antigenemia tests.

Results

CMV DNA was positive in 55 patients, with EBV reactivation being found in 29 of these (52.7%). EBV co-reactivation was significantly associated with aging (>64 years vs. ≤64 years, odds ratio 4.07, 95% confidence interval 1.06–15.6). When older patients were divided into two groups according to age, EBV co-reactivation occurred more frequently in early-old patients (aged 65–74 years) than in late-old patients (aged ≥75 years) (100.0% vs. 53.3%, respectively). Steroid pulse treatment was administered significantly more often in the early-old group than in those aged ≤64 years and ≥75 years (72.7% vs 27.6% vs 14.3%, respectively).

Conclusions

Co-reactivation of EBV in patients with CMV viremia highlighted early-old patients and may reflect treatment intensity as well as immunosenescence.

Impact of Human Cytomegalovirus and Human Herpesvirus 6 Infection on the Expression of Factors Associated with Cell Fibrosis and Apoptosis: Clues for Implication in Systemic Sclerosis Development

Systemic sclerosis (SSc) is a severe autoimmune disorder characterized by vasculopathy and multi-organ fibrosis; its etiology and pathogenesis are still largely unknown. Herpesvirus infections, particularly by human cytomegalovirus (HCMV) and human herpesvirus 6 (HHV-6), have been suggested among triggers of the disease based on virological and immunological observations. However, the direct impact of HCMV and/or HHV-6 infection on cell fibrosis and apoptosis at the cell microenvironment level has not yet been clarified. Thus, this study aimed to investigate the effects of HCMV and HHV-6 infection on the induction of pro-fibrosis or pro-apoptosis conditions in primary human dermal fibroblasts, one of the relevant SSc target cells. The analysis, performed by microarray in in vitro HCMV- or HHV-6-infected vs. uninfected cells, using specific panels for the detection of the main cellular factors associated with fibrosis or apoptosis, showed that both viruses significantly modified the expression of at least 30 pro-fibrotic and 20 pro-apoptotic factors. Notably, several recognized pro-fibrotic factors were highly induced, and most of them were reported to be involved in vivo in the multifactorial and multistep pathogenic process of SSc, thus suggesting a potential role of both HCMV and HHV-6.

Unusual presentation of fatal disseminated varicella zoster virus infection in a patient with lupus nephritis: a case report

Background

The risk of life-threatening complications, such as visceral disseminated varicella zoster virus (VZV) infection, is greater in immunosuppressed individuals, such as systemic lupus erythematosus (SLE) patients.

Case presentation

Here, a case is reported of a Caucasian woman diagnosed with lupus nephritis and anti-phospholipid syndrome, who was subjected to mycophenolate mofetil and high-dose steroid remission-induction therapy. Two months later she developed abdominal pain followed by a fatal rapid multi-organ failure. As no typical skin rashes were evident, death was initially attributed to catastrophic anti-phospholipid syndrome. However, autopsy and virological examinations on archival material revealed a disseminated VZV infection.

Conclusions

Overall, this case highlights the importance of having a high clinical suspicion of fatal VZV infections in heavily immunosuppressed SLE patients even when typical signs and symptoms are lacking.

Cytomegalovirus: A Troll in the ICU? Overview of the Literature and Perspectives for the Future

Cytomegalovirus (CMV) is one of the most pathogenic viruses in human. After a primary infection, CMV resides in the host for life as a latent infection. When immunity is reduced, CMV can escape the suppressive effects of the immune system and lead to viremia and antigenemia. This reactivation, first seen in transplant patients, has also been documented in non-immunocompromised CMV-seropositive critically ill patients and is associated with higher morbidity and mortality. In the latter, it is not clear whether CMV reactivation is an innocent bystander or the cause of this observed worse outcome. Two studies showed no difference in the outcome of CMV-seropositive and seronegative patients. In addition, proof-of-concept studies investigating prophylactic antiviral treatment to prevent CMV reactivation during critical illness, failed to show a beneficial effect on interleukin levels or clinical outcome. Further research is necessary to resolve the question whether CMV replication impairs the prognosis in non-immunocompromised critically ill patients. We here give a concise overview on the available data and propose strategies to further unravel this question. First, post-mortem investigation may be useful to evaluate the effect of viral replication on organ inflammation and function. Second, further research should focus on the question whether the level of viremia needs to exceed a threshold to be associated with worse outcome. Third, clinical and biochemical assessments may help to identify patients at high risk for reactivation. Fourth, preemptive treatment based upon early detection of the virus is currently under investigation. Finally, immune-stimulating biologicals may be beneficial in high-risk groups.

Current Understanding of Cytomegalovirus Reactivation in Critical Illness

Cytomegalovirus (CMV) reactivation has been described in adults with critical illness caused by diverse etiologies, especially severe sepsis, and observational studies have linked CMV reactivation with worse clinical outcomes in this setting. In this study, we review observational clinical data linking development of CMV reactivation with worse outcomes in patients in the intensive care unit, discuss potential biologically plausible mechanisms for a causal association, and summarize results of initial interventional trials that examined the effects of CMV prevention. These data, taken together, highlight the need for a randomized, placebo-controlled efficacy trial (1) to definitively determine whether prevention of CMV reactivation improves clinical outcomes of patients with critical illness and (2) to define the underlying mechanism(s).

Early herpes and TTV DNAemia in septic shock patients: a pilot study

BACKGROUND

Septic shock patients exhibit an increased incidence of viral reactivation. Precise timing of such reactivation-as an early marker of immune suppression, or as a consequence of the later-is not known precisely. Here, using a fully designed nucleic acid extraction automated procedure together with tailored commercial PCR kits, we focused on the description of early reactivation within the first week of ICU admission of several herpes viruses and Torque Teno virus (TTV) in 98 septic shock patients.

RESULTS

Most of septic shock patients had at least one viremia event during the first week (88%). TTV and herpesviruses were detected in 56% and 53% of septic shock patient, respectively. The two most frequent herpesviruses detected within the first week were EBV (35%) and HSV1 (26%). Different kinetic were observed among herpesviruses, faster for EBV and HSV1 than for CMV and HHV6. Although no association was found between herpes viremia and secondary infections, patients with herpesviridae-related viremia were more severe, e.g., higher SOFA scores and plasma lactate levels. While reactivating only 1 virus was not associated with mortality, patients with multiple viremia events had higher ICU mortality. Surprisingly, EBV + TTV early reactivation seemed associated with a lower D28 mortality. No clear association was observed between viremia and immune biomarkers.

CONCLUSION

Applying a semi-automated process of viral DNAemia determination to this cohort of 98 patients with septic shock, we observed that the number of patients with positive viremia increased during the first week in the ICU. Of note, there was no improvement in predicting the outcome when using viremia status. Nevertheless, this pilot study, introducing standardized procedures from extraction to detection, provides the basis for future standardized diagnostic criteria. A prospective longitudinal clinical study using these procedures will enable determination of whether such viremia is due to a lack of a latent virus control by the immune system or a true clinical viral infection.

Late-phase human herpesvirus 6B reactivation in hematopoietic stem cell transplant recipients

BACKGROUND

We sought to determine whether late-phase human herpesvirus 6B (HHV-6B) infection in hematopoietic stem cell transplant (HSCT) recipients was associated with serious outcomes and mortality.

METHODS

The occurrence and course of HHV-6B infection was monitored for at least 60 days after transplant using virus isolation and real-time polymerase chain reaction. Risk factors for late-phase HHV-6B infection were examined, and the propensity score was calculated with significant risk factors. The inverse probability-weighted multivariable logistic regression analysis was performed to estimate odds ratios (ORs) and the 95% confidence intervals (95% CI) for mortality.

RESULTS

Late-phase HHV-6B infection was observed in 12/89 (13.5%) of the HSCT recipients. Older age (OR: 10.3, 95% CI: 2.1/72.9, P = .0027), hematologic malignancy (OR: 10.3, 95% CI: 1.8/97.1, P = .0063), unrelated donor transplantation (OR: 5.3, 95% CI: 1.1/36.0, P = .0345), and sex-mismatched donor transplantation (OR: 6.3, 95% CI: 1.4/39.5, P = .0149) were identified as risk factors for late-phase HHV-6B infection. Fifteen subjects died (17%). Inverse probability-weighted multivariable logistic model analysis revealed that late-phase HHV-6B infection was an independent risk factor for mortality (OR: 4.2, 95% CI: 1.7/11.0, P = .0012). Among 5 of the fatal cases of late-phase HHV-6B infection, viral infection might be associated with severe clinical manifestations.

CONCLUSION

Late-phase HHV-6B infection in HSCT recipients was associated with worse outcomes. The full spectrum of clinical features of the infection has not been fully elucidated, and therefore, recipients with high-risk factors for late-phase HHV-6B infection should be carefully monitored.

The Potential Harm of Cytomegalovirus Infection in Immunocompetent Critically Ill Children

Cytomegalovirus (CMV) is a ubiquitous infection that causes disease in congenitally infected children and immunocompromised patients. Although nearly all CMV infections remain latent and asymptomatic in immunologically normal individuals, numerous studies have found that systemic viral reactivation is common in immunocompetent critically ill adults, as measured by detection of CMV in the blood (viremia). Furthermore, CMV viremia is strongly correlated with adverse outcomes in the adult intensive care unit (ICU), including prolonged stay, duration of mechanical ventilation, and death. Increasing evidence, including from a randomized clinical trial of antiviral treatment, suggests that these effects of CMV may be causal. Therefore, interventions targeting CMV might improve outcomes in adult ICU patients. CMV may have an even greater impact on critically ill children, particularly in low and middle income countries (LMIC), where CMV is regularly acquired in early childhood, and where inpatient morbidity and mortality are inordinately high. However, to date, there are few data regarding the clinical relevance of CMV infection or viremia in immunocompetent critically ill children. We propose that CMV infection should be studied as a potential modifiable cause of disease in critically ill children, and that these studies be conducted in LMIC. Below, we briefly review the role of CMV in immunologically normal critically ill adults and children, outline age-dependent differences in CMV infection that may influence ICU outcomes, and describe an agenda for future research.

EASL Clinical Practical Guidelines on the management of acute (fulminant) liver failure

The term acute liver failure (ALF) is frequently applied as a generic expression to describe patients presenting with or developing an acute episode of liver dysfunction. In the context of hepatological practice, however, ALF refers to a highly specific and rare syndrome, characterised by an acute abnormality of liver blood tests in an individual without underlying chronic liver disease. The disease process is associated with development of a coagulopathy of liver aetiology, and clinically apparent altered level of consciousness due to hepatic encephalopathy. Several important measures are immediately necessary when the patient presents for medical attention. These, as well as additional clinical procedures will be the subject of these clinical practice guidelines.

Long-term alterations in monocyte function after elective cardiac surgery

Optimal immunological homoeostasis determines the long-term recovery of patients in the postoperative period. The functional adaptability of monocytes plays a pivotal role in adjusting the host's response to an insult, immunostasis and long-term health, and may help to determine successful recovery. We undertook a longitudinal analysis of the functional adaptability of monocytes in 20 patients undergoing heart surgery with cardiopulmonary bypass, as a model of severe stress. Using each patient's pre-cardiopulmonary bypass data as a baseline, we investigated the characteristics of peripheral blood monocytes' functional plasticity in-vitro before elective bypass, and three months afterwards. Approximately 30% of subjects showed diminished monocyte plasticity, as demonstrated by decreased monocyte differentiation into dendritic cells three months after bypass. Diminished monocyte functional plasticity was related to over-production of macrophage colony-stimulating factor. Adding a neutralising antibody to macrophage colony-stimulating factor corrected the monocytes' differentiation defect. Finally, patients with reduced monocyte plasticity had significantly elevated serum C-reactive protein, with a concomitant increase in cytomegalovirus IgG antibody titres, suggestive of the acquisition of immuno-suppressive traits. Our study shows that severe surgical stress resulted in a lasting immunological defect in individuals who had seemingly recovered.

The cumulative burden of double-stranded DNA virus detection after allogeneic HCT is associated with increased mortality

Strategies to prevent active infection with certain double-stranded DNA (dsDNA) viruses after allogeneic hematopoietic cell transplantation (HCT) are limited by incomplete understanding of their epidemiology and clinical impact. We retrospectively tested weekly plasma samples from allogeneic HCT recipients at our center from 2007 to 2014. We used quantitative PCR to test for cytomegalovirus, BK polyomavirus, human herpesvirus 6B, HHV-6A, adenovirus, and Epstein-Barr virus between days 0 and 100 post-HCT. We evaluated risk factors for detection of multiple viruses and association of viruses with mortality through day 365 post-HCT with Cox models. Among 404 allogeneic HCT recipients, including 125 cord blood, 125 HLA-mismatched, and 154 HLA-matched HCTs, detection of multiple viruses was common through day 100: 90% had ≥1, 62% had ≥2, 28% had ≥3, and 5% had 4 or 5 viruses. Risk factors for detection of multiple viruses included cord blood or HLA-mismatched HCT, myeloablative conditioning, and acute graft-versus-host disease (P values < .01). Absolute lymphocyte count of <200 cells/mm³ was associated with greater virus exposure on the basis of the maximum cumulative viral load area under the curve (AUC) (P = .054). The maximum cumulative viral load AUC was the best predictor of early (days 0-100) and late (days 101-365) overall mortality (adjusted hazard ratio [aHR] = 1.36, 95% confidence interval [CI] [1.25, 1.49], and aHR = 1.04, 95% CI [1.0, 1.08], respectively) after accounting for immune reconstitution and graft-versus-host disease. In conclusion, detection of multiple dsDNA viruses was frequent after allogeneic HCT and had a dose-dependent association with increased mortality. These data suggest opportunities to improve outcomes with better antiviral strategies.

Association Between Cytomegalovirus Reactivation and Clinical Outcomes in Immunocompetent Critically Ill Patients: A Systematic Review and Meta-Analysis

Background

The aim of our systematic review was to investigate the association between cytomegalovirus (CMV) reactivation and outcomes in immunocompetent critically ill patients.

Methods

We searched electronic databases and gray literature for original studies and abstracts published between 1990 and October 2016. The review was limited to studies including critically ill immunocompetent patients. Cytomegalovirus reactivation was defined as positive polymerase chain reaction, pp65 antigenemia, or viral culture from blood or bronchoalveolar lavage. Selected patient-centered outcomes included mortality, duration of mechanical ventilation, need for renal replacement therapy (RRT), and nosocomial infections. Health resource utilization outcomes included intensive care unit and hospital lengths of stay.

Results

Twenty-two studies were included. In our primary analysis, CMV reactivation was associated with increased ICU mortality (odds ratio [OR], 2.55; 95% confidence interval [CI], 1.87–3.47), overall mortality (OR, 2.02; 95% CI, 1.60–2.56), duration of mechanical ventilation (mean difference 6.60 days; 95% CI, 3.09–10.12), nosocomial infections (OR, 3.20; 95% CI, 2.05–4.98), need for RRT (OR, 2.37; 95% CI, 1.31–4.31), and ICU length of stay (mean difference 8.18 days; 95% CI, 6.14–10.22). In addition, numerous sensitivity analyses were performed.

Conclusions

In this meta-analysis, CMV reactivation was associated with worse clinical outcomes and greater health resource utilization in critically ill patients. However, it remains unclear whether CMV reactivation plays a causal role or if it is a surrogate for more severe illness.

Cytomegalovirus Infection in Patients with Sepsis Due to Bloodstream Infections: Lower Risk and Better Outcomes in New versus Already Hospitalised Intensive Care Unit Admissions

Few studies have examined cytomegalovirus (CMV) reactivation exclusively in immunocompetent patients with sepsis due to bloodstream infections. In a cohort of CMV-seropositive critically ill otherwise non-immunosuppressed patients with sepsis due to bloodstream infection, weekly testing for CMV viraemia was performed. Outcomes were assessed at 30 days or until death/discharge from the intensive care unit (ICU). CMV viraemia developed in 20% (20/100) of the patients. Age ( P=0.044) and blood transfusions ( P=0.022) were significantly associated with CMV viraemia. There was no difference in the primary endpoint (mortality and/or multi-organ failure) between patients with and without CMV viraemia ( P=0.49). However, CMV viraemia was associated with significantly fewer ICU-free days ( P=0.023) and fewer ventilator-free days ( P=0.031). Patients hospitalised in the ICU for more than 48 hours prior to the onset of bloodstream infection were more likely to develop CMV viraemia ( P=0.006), have high-grade viraemia ( P=0.010), and fewer ICU-free days ( P=0.018) and ventilator-free days ( P=0.029) than those admitted within 48 hours of bloodstream infection. Thus, CMV reactivation was associated with fewer ICU- and ventilator-free days, however overall mortality was not affected. Patients already in the ICU at the onset of sepsis had higher risk of CMV reactivation and worse outcomes than new ICU-bound patients suggesting that a targeted approach for interventions for CMV could conceivably be directed towards those with a more protracted course of illness.

Severe infections in neutropenic patients

PURPOSE OF REVIEW

Severe infections in neutropenic patients can rapidly progress to septic shock and multiorgan failure with a high associated mortality. In this article we discuss current practice, emerging trends and controversies, including the prophylactic and empiric use of antimicrobial therapy, and advances in cellular and immunotherapy.

RECENT FINDINGS

Neutropenia is no longer a consistent factor predicting poor outcome in haematological patients admitted to the ICU. Severe infections in neutropenic patients are often polymicrobial, and pathogen resistance remains a challenge. Invasive fungal infection is still predictive of poor outcome. There has been a rapid expansion in the diagnostics and treatment modalities available for patients with invasive fungal infection. Use of growth factors, polyvalent immunoglobulin, and cellular therapy appear to be of value in certain groups of patients. There is a move away from the use of noninvasive ventilation and the use of high-flow nasal oxygen therapy is one of a number of novel respiratory support strategies that is yet to be evaluated in this patient population.

SUMMARY

Translation of current advances in antimicrobial, cellular and immunotherapy, and diagnostics to aid clinical management by the bedside is important in reducing morbidity and mortality for neutropenic patients with severe infection.

Impact of cytomegalovirus reactivation on clinical outcomes in immunocompetent critically ill patients: protocol for a systematic review and meta-analysis

BACKGROUND

Cytomegalovirus (CMV) reactivation in critically ill patients is a well-recognized phenomenon with an incidence as high as 71 %. A number of studies have investigated the association between CMV reactivation and outcomes in critically ill patients with conflicting results. We propose to conduct a systematic review and meta-analysis to determine the impact of CMV reactivation on patient-centered outcomes and measures of health resource utilization in immunocompetent critically ill patients.

METHODS

In consultation with a research librarian, a search strategy will be developed and electronic databases (i.e., Ovid MEDLINE, Ovid EMBASE, and the Cochrane Library including the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials (CENTRAL)) will be searched for original studies. Selected grey literature sources will be hand-searched. Search themes will include cytomegalovirus, intensive care unit, and sepsis. Citation screening, selection, quality assessment, and data abstraction will be performed in duplicate. Pooled effect estimates of the impact of CMV reactivation on selected patient-centered outcomes and measures of health resource utilization will be described.

DISCUSSION

This systematic review aims to explore the impact of CMV reactivation on patient-centered outcomes and health resource utilization in immunocompetent critically ill patients. Our results will help to better define the burden of disease associated with CMV reactivation. Indeed, evidence to date suggests increased mortality in this patient population. However, the relationship between CMV reactivation and health resource utilization remains less clear. Based on our results, future study on the impact of CMV treatment or prophylaxis on outcomes (including those other than mortality) may be warranted.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016035446.

Cytomegalovirus and Epstein-Barr virus reactivation in the intensive care unit

AIM

The purpose of this work was to evaluate the reactivation of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in immunocompetent patients in the intensive care unit (ICU) and to identify risk factors associated with reactivation.

MATERIALS AND METHODS

In this observational prospective study, 60 adult immunocompetent patients who stayed at least 7 days in an ICU were evaluated. During hospitalization, the viral load was monitored at admission and on day 7 with polymerase chain reaction to detect viral reactivation and weekly thereafter on days 14, 21, and 28 if hospitalization continued.

RESULTS

The mean age of patients was 63.3 years (±23.4 years) and 34 (56.7 %) of them were male. Mean APACHE II scores for patients was 25 at admission. Of these patients, 28 were hospitalized in the internal ICU and 32 were hospitalized in the anesthesiology ICU. CMV/EBV reactivation was found in 17 individuals (12 for EBV, 3 for CMV, and 2 for both). The median high-sensitive C-reactive protein value in patients with CMV reactivation was significantly higher than in those patients without CMV reactivation (p = 0.037). EBV reactivation was statistically higher in patients with mechanical ventilation compared to patients without mechanical ventilation (p = 0.023). EBV reactivation in patients with fever was found to be statistically higher than in the patients without fever (p = 0.035).

CONCLUSION

There is a need for extended studies with a larger number of patients from specific groups to better understand the reactivation frequency and identify risk factors. EBV and CMV reactivation should be taken into consideration in critically ill patients with fever, without specific symptoms and unresponsive to the treatment.

Adaptive immune function in critical illness

PURPOSE OF REVIEW

This review is being published to update the literature on the function of the adaptive immune system in critical illness, specifically sepsis and acute lung injury. We have focused on the role of T cells in these syndromes.

RECENT FINDINGS

The adaptive immune response becomes dysfunctional during sepsis and acute lung injury in very similar ways. Many of the abnormalities contribute to morbidity and mortality. Immunoparalysis captures the breadth of the dysfunction in that T-cell functions are broadly suppressed after the early proinflammatory stages of illness. Lymphocyte apoptosis, decreased antigen responsiveness, decreased and altered cytokine expression, upregulation of inhibitory molecules, and expansion of the suppressive regulatory T-cell population are mechanisms involved. Each of these abnormalities can be reversed with improvement in experimental outcomes.

SUMMARY

Immunoparalysis of the adaptive immune system occurs in sepsis and acute lung injury, and is critical to the outcome. Blocking the inhibited pathways and immunostimulant cytokines improved lymphocyte function and outcome. Many such blocking agents are already effective for other diseases and could be used for immunoparalysis. Unfortunately, there is no diagnostic marker yet. In order to provide the right therapy at the right time, advancements in immunomonitoring are necessary.

Absence of human herpesvirus 6B detection in association with illness in children undergoing cancer chemotherapy

The lymphotropic herpesviruses, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6B (HHV-6B) can reactivate and cause disease in organ transplant recipients; the contributions of HHV-6A and HHV-7 to disease are less certain. Less is known about their pathogenic roles in children undergoing treatment for malignancies. Children with newly diagnosed cancer were followed for 24 months. Clinical information and blood samples were collected during routine visits and during acute visits for fever or possible viral infections. Lymphotropic herpesvirus DNA in blood was measured by polymerase chain reaction (PCR). Although HHV-6B DNA was detected at least once in about half of the patients; the other viruses were seldom detected. There was no association between HHV-6B detection and individual acute clinical events, however, HHV-6B detection was more common in children who experienced more frequent acute clinical events. In children being treated for various malignancies, HHV-6B detection was common, but was not associated with individual events of acute illness. Thus, if HHV-6B is not assessed longitudinally, clinical events may be misattributed to the virus. The elevated frequency of detection of HHV-6B in sicker children is consistent with prior reports of its detection during apparently unrelated acute clinical events. J. Med. Virol. 88:1427-1437, 2016. © 2016 Wiley Periodicals, Inc.

Fulminant hepatic failure attributed to infection with human herpesvirus 6 (HHV-6) in an immunocompetent woman: A case report and review of the literature

Mild disease due to human herpesvirus-6 (HHV-6) has been reported in healthy children. Severe disease due to this virus can occur in immunocompromised patients but is rarely reported in previously healthy adults. We report the case of a previously healthy woman who presented with a skin rash, mild upper respiratory symptoms, and abdominal pain and succumbed to fulminant hepatic failure attributed to infection with HHV-6B. HHV-6 may be more commonly associated with fulminant hepatitis in immunocompetent patients than previously thought and should be considered in the differential diagnosis of patients presenting with skin rash, upper respiratory symptoms, and unexplained hepatitis.

Cytomegalovirus reactivation in ICU patients

Introduction

Approximately 20 years have passed since we reported our results of histologically proven cytomegalovirus (CMV) pneumonia in non-immunocompromised ICU patients. Even if there are more recent reports suggesting that CMV may worsen the outcomes for ICU patients, there is no definite answer to this question: is CMV a potential pathogen for ICU patients or is it simply a bystander?

Methods

We will describe the pathophysiology of active CMV infection and the most recent insights concerning the epidemiological aspects of these reactivations.

Major findings

Cytomegalovirus can be pathogenic by a direct organ insult (such as for the lung), by decreasing host defences against other microorganisms and/or by enhancing the body’s inflammatory response (as in acute respiratory distress syndrome). The incidence of active CMV infection is dependent on the diagnostic method used. Using the most sophisticated available biological tools, the incidence can reach 15–20 % of ICU patients (20–40 % in ICU patients with positive CMV serology). In adequately powered cohorts of patients, active CMV infection appears to be associated with worse outcomes for mechanically ventilated ICU patients.

Discussion

There is no absolute direct proof of a negative impact of active CMV infection on the health outcomes of mechanically ventilated patients. Prospective randomized trials are lacking. Future trials should examine the potential benefits for health outcomes of using antiviral treatments. Such treatments could be prophylactic, pre-emptive or used only when there is an end-organ disease.

Conclusion

Cytomegalovirus infection may affect health outcomes for ICU patients. Additional prospective trials are necessary to confirm this hypothesis.

Cytomegalovirus reactivation and mortality in patients with acute respiratory distress syndrome

Purpose

Cytomegalovirus (CMV) reactivation occurs frequently in patients with the acute respiratory distress syndrome (ARDS) and has been associated with increased mortality. However, it remains unknown whether this association represents an independent risk for poor outcome. We aimed to estimate the attributable effect of CMV reactivation on mortality in immunocompetent ARDS patients.

Methods

We prospectively studied immunocompetent ARDS patients who tested seropositive for CMV and remained mechanically ventilated beyond day 4 in two tertiary intensive care units in the Netherlands from 2011 to 2013. CMV loads were determined in plasma weekly. Competing risks Cox regression was used with CMV reactivation status as a time-dependent exposure variable. Subsequently, in sensitivity analyses we adjusted for the evolution of disease severity until onset of reactivation using marginal structural modeling.

Results

Of 399 ARDS patients, 271 (68 %) were CMV seropositive and reactivation occurred in 74 (27 %) of them. After adjustment for confounding and competing risks, CMV reactivation was associated with overall increased ICU mortality (adjusted subdistribution hazard ratio (SHR) 2.74, 95 % CI 1.51–4.97), which resulted from the joint action of trends toward an increased mortality rate (direct effect; cause specific hazard ratio (HR) 1.58, 95 % CI 0.86–2.90) and a reduced successful weaning rate (indirect effect; cause specific HR 0.83, 95 % CI 0.58–1.18). These associations remained in sensitivity analyses. The population-attributable fraction of ICU mortality was 23 % (95 % CI 6–41) by day 30 (risk difference 4.4, 95 % CI 1.1–7.9).

Conclusion

CMV reactivation is independently associated with increased case fatality in immunocompetent ARDS patients who are CMV seropositive.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-015-4071-z) contains supplementary material, which is available to authorized users.