Cytomegalovirus reactivation and mortality in patients with acute respiratory distress syndrome

Cytomegalovirus reactivation in the lower respiratory tract as an independent risk factor for mortality in critically Ill patients

BACKGROUND

The clinical significance of cytomegalovirus reactivation in the lower respiratory tract (LRT) of critically ill patients remains unclear. We aimed to investigate the association between cytomegalovirus reactivation detected in LRT and intensive care unit (ICU) prognosis.

METHODS

This study included critically ill patients admitted to a medical ICU at a tertiary referral center in South Korea between January 2021 and June 2023. Cytomegalovirus load in LRT samples collected via bronchoscopy was measured within 7 days of admission. Detection of cytomegalovirus DNA in LRT was defined as reactivation. Associations between cytomegalovirus reactivation and ICU, in-hospital, 30-day, and 90-day mortality were assessed using multivariable Fine-Gray model adjusted for major clinical factors.

RESULTS

Of the 322 patients (median age 68 years, 66.8% male), 145 (45%) had cytomegalovirus reactivation in the LRT. Cytomegalovirus reactivation was independently associated with increased ICU (adjusted subdistribution hazard ratio [aSHR], 2.28; 95% confidence interval [CI], 1.46-3.56), in-hospital (aSHR, 2.00; 95% CI, 1.44-2.78), 30-day (aSHR, 2.11; 95% CI, 1.42-3.13), and 90-day mortality (aSHR, 2.05; 95% CI, 1.45-2.88). Anti-cytomegalovirus therapy was significantly associated with reduced ICU mortality in patients with radiologic findings suggestive of cytomegalovirus pneumonia (P for interaction = 0.001), but was linked to increased mortality in patients with positive bacterial cultures (P for interaction = 0.002).

CONCLUSION

Cytomegalovirus reactivation in the LRT is associated with poor outcomes in critically ill patients. Anti-cytomegalovirus therapy was not associated with overall survival outcomes; however, the subgroup with radiologic findings of cytomegalovirus pneumonia suggested benefits, while the subgroup with bacterial co-infections suggested harmful effects. Randomized controlled trials are needed.

Viral reactivations and fungal infections in nonresolving acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a condition affecting 10% of patients requiring admission to the intensive care unit and results from endothelial dysfunction, alveolar epithelial injury and unbalanced inflammation, leading to exudative pulmonary oedema. A significant portion of these patients experience a lung injury that fails to resolve. Persistent or worsening respiratory failure beyond 5 days after the initiation of mechanical ventilation is referred to as nonresolving ARDS. Viral and fungal pathogens can exploit the hyperinflammatory environment and altered immune landscape in ARDS, perpetuating a cycle of ongoing inflammation and lung injury, thereby contributing to the progression towards and persistence of nonresolving ARDS, even in previously immunocompetent patients. This review discusses the significance, pathophysiology, diagnostic challenges and key knowledge gaps concerning various viral and fungal pathogens in nonresolving ARDS, with a particular focus on influenza-associated and COVID-19-associated pulmonary aspergillosis and pulmonary reactivation of Herpesviridae, such as cytomegalovirus and herpes simplex virus. Diagnosing these infections is challenging due to their nonspecific clinical presentation and the inability of current tests to distinguish between fungal colonisation or asymptomatic viral shedding and clinically significant infections or reactivations. A deeper understanding of the complex interplay between these pathogens and the host immune system in the context of ARDS, combined with advances in diagnostic and therapeutic strategies, has the potential to enhance the management and prognosis of patients with nonresolving ARDS.

What intensivists need to know about cytomegalovirus infection in immunocompromised ICU patients

PURPOSE

Advances in therapeutic care are leading to an increase in the number of patients living with overt immunosuppression. These patients are at risk of cytomegalovirus (CMV) infection and disease that can lead to or develop during ICU admission. This manuscript aims to describe the clinical presentation, risk factors, and management of CMV infection and disease in this patient population.

METHODS

We conducted a literature search in PubMed up to April 2024, focusing on CMV infection and disease in patients with overt immunosuppression (hematopoietic stem cell and solid organ transplantation, solid or hematologic malignancies, HIV infection, immunosuppressive drugs, including corticosteroids, and primary immunodeficiencies) admitted to the intensive care unit (ICU). As there is limited ICU-specific data on CMV in immunosuppressed patients, many of the findings were extrapolated from the general literature.

RESULTS

CMV infection and disease in immunocompromised critically ill patients is associated with increased mortality and presents significant management challenges. Clinical manifestations are diverse, shaped by the underlying immune deficiency and primary disease. Pneumonia and encephalitis are among the most severe CMV end-organ diseases. CMV infection may also increase the risk of secondary infections and induce life-threatening conditions, such as thrombotic microangiopathy. Importantly, CMV reactivation is not synonymous with CMV disease, and qPCR testing of body fluids cannot reliably differentiate between viral shedding and tissue-invasive infection, which requires histopathological confirmation. Ganciclovir is commonly the first-line anti-viral, though maribavir shows potential for patients unresponsive to other antivirals. Identifying patients who require prophylactic or preemptive antiviral therapy is essential.

CONCLUSIONS

CMV infection and disease in critically ill immunocompromised patients pose a unique challenge for intensivists. The broad spectrum of clinical presentations and the difficulty in distinguishing CMV-related symptoms from other causes require a high level of clinical suspicion. Accurate interpretation of nucleic acid load levels and careful evaluation of CMV's pathogenic role when it is found are critical. Further studies focusing specifically on CMV infection and disease in critically ill immunocompromised patients are needed to optimize management strategies.

Active cytomegalovirus infection in mechanically ventilated patients with sepsis

BACKGROUND

Active cytomegalovirus (CMV) infection is associated with poor prognosis in septic patients with critical illness. Patients of septic category are highly likely to benefit from prophylactic antiviral therapy. Nevertheless, the clinical characteristics for CMV reactivation are lacking among septic patients requiring mechanical ventilation. The aim of this study was to investigate the incidence, risk factors, and clinical outcomes regarding active CMV infection in mechanically ventilated patients with sepsis.

METHODS

A single-center, retrospective cohort study conducted from January 2021 to December 2023 that included septic patients on mechanical ventilation at the intensive care unit (ICU) of a national hospital. Study participants were divided into active and non-active CMV infection groups based on CMV DNAemia within a 28-day hospitalization period in ICU. Clinical features, laboratory findings, treatment measures, and clinical outcomes were compared between the two groups.

RESULTS

Among 118 septic patients, 21 (17.8%) exhibited active CMV infection within 28-day ICU admission. Hemoglobin served as an independent risk factor and predictor for active CMV infection (P < 0.05). Moreover, the duration of mechanical ventilation and ICU stay in active CMV infection patients were significantly higher than in the comparison group (P < 0.05).

CONCLUSIONS

Active CMV infection is common and associated with adverse clinical outcomes in mechanically ventilated patients with sepsis. A low level of hemoglobin is an independent risk factor for active CMV infection. Further prospective studies are warranted to assess the efficacy of initiating prophylactic and preemptive antiviral therapies among patients with sepsis disorders.

Quantitative PCR for early detection of human cytomegalovirus end-organ disease in immunocompetent host: A retrospective single-center study

BACKGROUND

Tissue-invasive end-organ disease (EOD) caused by cytomegalovirus (CMV) is less frequently reported in immunocompetent patients compared to immunocompromised patients. In this study, we investigated the association between CMV viremia and CMV end-organ disease in immunocompetent patients.

METHODS

Adult patients (≥18 years old) with CMV viremia were screened from January 2010 to June 2022. The primary outcome was the presence of CMV EOD. Risk factors associated with CMV EOD were analyzed, and a receiver operating characteristic curve was plotted to determine the most accurate cutoff value of the CMV titer for the prediction of CMV EOD.

RESULTS

Among the 106 immunocompetent patients with CMV viremia, 31 exhibited CMV EOD. Gastrointestinal tract disease was the most common. The log10 value of the CMV titer was significantly associated with the occurrence of CMV EOD in immunocompetent patients with CMV viremia. The optimal cut-off CMV titer for the prediction of CMV EOD was 749 IU/mL.

CONCLUSIONS

Our study suggests the potential association between high CMV titers and the development of CMV end-organ diseases and describes the diagnostic performance and utility of quantitative PCR as a surrogate marker for predicting the occurrence of CMV EOD in immunocompetent patients.

The Wide Spectrum of Presentations of Cytomegalovirus Infection in Immunocompetent Hosts: An Exhaustive Narrative Review

CMV is a ubiquitous DNA virus that establishes infection and results in 40-100% seropositivity. Viral replication occurs following an acquired primary infection (or reinfection) or by the reactivation of life-long latency. In immunocompetent patients, CMV infection is mostly asymptomatic or mild and self-limited. However, an extensive review of the literature published up to April 2024 reveals that despite immunocompetence, CMV can cause a very large variety of clinical syndromes in any part of the gastrointestinal tract (the most common pattern), the central or peripheral nervous system, and the eyes, as well as hematological, pulmonary, cardiac, and cutaneous disease. Not uncommonly, more than one system is involved, and though the disease is often self-limited, treatment with intravenous ganciclovir or oral valganciclovir may be required, and in isolated cases, fatalities may occur. Thus, a potential CMV infection should be considered in the differential of myriad syndromes in non-immunocompromised patients. Associated systemic symptoms (fever, sweats, and weight loss), lymphocytosis, and hepatitis are not uncommon and can be a useful clue. Some populations, such as critically ill patients in intensive care, pregnant women, elderly patients, and those with inflammatory bowel disease, may be more susceptible. Moreover, the potential of past, latent CMV infection (i.e., CMV seropositivity) to be associated with significant cardiovascular morbidity and all-cause mortality years later is intriguing and requires further study. All these data indicate the outstanding importance of developing a vaccine against CMV, which hopefully will become available in the foreseeable future. Meanwhile, a solid diagnosis of active CMV infection can be quickly established (or ruled out) by widely available serology tests and PCR amplification, and clinicians in all disciplines need to be more aware of the diverse guises of CMV infection and remember to consider it in any host, including an immunocompetent one.

Pulmonary herpes simplex virus and cytomegalovirus in patients with acute respiratory distress syndrome related to COVID-19

PURPOSE

Human herpesviruses, particularly cytomegalovirus (CMV) and herpes simplex virus (HSV), frequently reactivate in critically ill patients, including those with acute respiratory distress syndrome (ARDS) related to coronavirus disease 2019 (COVID-19). The clinical interpretation of pulmonary herpesvirus reactivation is challenging and there is ongoing debate about its association with mortality and benefit of antiviral medication. We aimed to quantify the incidence and pathogenicity of pulmonary CMV and HSV reactivations in critically ill COVID-19 patients.

METHODS

Mechanically ventilated COVID-19 patients seropositive for CMV or HSV were included in this observational cohort study. Diagnostic bronchoscopy with bronchoalveolar lavage was performed routinely and analyzed for alveolar viral loads and inflammatory biomarkers. Utilizing joint modeling, we explored the dynamic association between viral load trajectories over time and mortality. We explored alveolar inflammatory biomarker dynamics between reactivated and non-reactivated patients.

RESULTS

Pulmonary reactivation (> 104 copies/ml) of CMV occurred in 6% of CMV-seropositive patients (9/156), and pulmonary reactivation of HSV in 37% of HSV-seropositive patients (63/172). HSV viral load dynamics prior to or without antiviral treatment were associated with increased 90-day mortality (hazard ratio [HR] 1.24, 95% confidence interval [CI] 1.04-1.47). The alveolar concentration of several inflammatory biomarkers increased with HSV reactivation, including interleukin (IL)-6, IL-1β, granulocyte colony stimulating factor (G-CSF), and tumor necrosis factor (TNF).

CONCLUSION

In mechanically ventilated COVID-19 patients, HSV reactivations are common, while CMV reactivations were rare. HSV viral load dynamics prior to or without antiviral treatment are associated with mortality. Alveolar inflammation is elevated after HSV reactivation.

Clinical characteristics and outcomes of immunocompromised critically ill patients with cytomegalovirus end-organ disease: a multicenter retrospective cohort study

BACKGROUND

Cytomegalovirus (CMV) infection in patients with cellular immune deficiencies is associated with significant morbidity and mortality. However, data on CMV end-organ disease (CMV-EOD) in critically ill, immunocompromised patients are scarce. Our objective here was to describe the clinical characteristics and outcomes of CMV-EOD in this population.

METHODS

We conducted a multicenter, international, retrospective, observational study in adults who had CMV-EOD and were admitted to any of 18 intensive care units (ICUs) in France, Israel, and Spain in January 2010-December 2021. Patients with AIDS were excluded. We collected the clinical characteristics and outcomes of each patient. Survivors and non-survivors were compared, and multivariate analysis was performed to identify risk factors for hospital mortality.

RESULTS

We studied 185 patients, including 80 (43.2%) with hematologic malignancies, 55 (29.7%) with solid organ transplantation, 31 (16.8%) on immunosuppressants, 16 (8.6%) with solid malignancies, and 3 (1.6%) with primary immunodeficiencies. The most common CMV-EOD was pneumonia (n = 115, [62.2%] including 55 [47.8%] with a respiratory co-pathogen), followed by CMV gastrointestinal disease (n = 64 [34.6%]). More than one organ was involved in 16 (8.8%) patients. Histopathological evidence was obtained for 10/115 (8.7%) patients with pneumonia and 43/64 (67.2%) with GI disease. Other opportunistic infections were diagnosed in 69 (37.3%) patients. Hospital mortality was 61.4% overall and was significantly higher in the group with hematologic malignancies (75% vs. 51%, P = 0.001). Factors independently associated with higher hospital mortality were hematologic malignancy with active graft-versus-host disease (OR 5.02; 95% CI 1.15-27.30), CMV pneumonia (OR 2.57; 95% CI 1.13-6.03), lymphocytes < 0.30 × 109/L at diagnosis of CMV-EOD (OR 2.40; 95% CI 1.05-5.69), worse SOFA score at ICU admission (OR 1.18; 95% CI 1.04-1.35), and older age (OR 1.04; 95% CI 1.01-1.07).

CONCLUSIONS

Mortality was high in critically ill, immunocompromised patients with CMV-EOD and varied considerably with the cause of immunodeficiency and organ involved by CMV. Three of the four independent risk factors identified here are also known to be associated with higher mortality in the absence of CMV-EOD. CMV pneumonia was rarely proven by histopathology and was the most severe CMV-EOD.

Qualitative evaluation of connective tissue disease with cytomegalovirus infection: A meta-analysis of case reports

BACKGROUND

The primary therapies for connective tissue disease include glucocorticoids and immunosuppressants. However, their prolonged usage can precipitate opportunistic infections, such as cytomegalovirus infection. When managing connective tissue disease complicated by cytomegalovirus infection, judicious selection of treatment modalities is crucial. This involves assessing the necessity for antiviral therapy and contemplating the reduction or cessation of glucocorticoids and immunosuppressants.

OBJECTIVE

This investigation sought to methodically review existing literature regarding treating connective tissue disease patients with cytomegalovirus infection.

METHODS

On July 5, 2023, an exhaustive literature search was conducted. Data analysis utilized the Kruskal-Wallis test or one-way analysis of variance, supplemented by Bonferroni post hoc testing.

RESULTS

Our meta-analysis incorporated 88 studies encompassing 146 connective tissue disease patients with CMV infections. The results indicated that patients with connective tissue disease and cytomegalovirus disease benefitted more from antiviral therapy than those not receiving such treatment (P = 0.003, P < 0.005). Furthermore, the strategic reduction of glucocorticoids and/or immunosuppressants was beneficial (P = 0.037, P < 0.05). Poor clinical outcomes with glucocorticoid-immunosuppressant combination therapy compared to other treatment modalities. The findings also suggested that CMV infection patients fare better without Cyclosporine A than using it (P = 0.041, P < 0.05).

CONCLUSION

Antiviral therapy is a viable treatment option in cases of connective tissue disease co-occurring with cytomegalovirus disease. Additionally, when connective tissue disease is stable, there is potential merit in reducing glucocorticoids and/or immunosuppressants, especially avoiding the combination of these drugs. For all cytomegalovirus infection patients, Cyclosporine A may be avoided wherever possible for selecting immunosuppressive agents if its use is not deemed essential in the treatment regimen.

Cytomegalovirus infection in non-immunocompromised critically ill patients: A management perspective

Critically ill patients are a vulnerable group at high risk of developing secondary infections. High disease severity, prolonged intensive care unit (ICU) stay, sepsis, and multiple drugs with immunosuppressive activity make these patients prone to immuneparesis and increase the risk of various opportunistic infections, including cytomegalovirus (CMV). CMV seroconversion has been reported in up to 33% of ICU patients, but its impact on patient outcomes remains a matter of debate. Even though there are guidelines regarding the management of CMV infection in immunosuppressive patients with human immunodeficiency virus/ acquired immuno deficiency syndrome, the need for treatment and therapeutic approaches in immunocompetent critically ill patients is still ambiguous. Even the diagnosis of CMV infection may be challenging in such patients due to non-specific symptoms and multiorgan involvement. Hence, a better understanding of the symptomatology, diagnostics, and treatment options may aid intensive care physicians in ensuring accurate diagnoses and instituting therapeutic interventions.

The Impact of Pathogens on Sepsis Prevalence and Outcome

Sepsis, a severe global healthcare challenge, is characterized by significant morbidity and mortality. The 2016 redefinition by the Third International Consensus Definitions Task Force emphasizes its complexity as a "life-threatening organ dysfunction caused by a dysregulated host response to infection". Bacterial pathogens, historically dominant, exhibit geographic variations, influencing healthcare strategies. The intricate dynamics of bacterial immunity involve recognizing pathogen-associated molecular patterns, triggering innate immune responses and inflammatory cascades. Dysregulation leads to immunothrombosis, disseminated intravascular coagulation, and mitochondrial dysfunction, contributing to the septic state. Viral sepsis, historically less prevalent, saw a paradigm shift during the COVID-19 pandemic, underscoring the need to understand the immunological response. Retinoic acid-inducible gene I-like receptors and Toll-like receptors play pivotal roles, and the cytokine storm in COVID-19 differs from bacterial sepsis. Latent viruses like human cytomegalovirus impact sepsis by reactivating during the immunosuppressive phases. Challenges in sepsis management include rapid pathogen identification, antibiotic resistance monitoring, and balancing therapy beyond antibiotics. This review highlights the evolving sepsis landscape, emphasizing the need for pathogen-specific therapeutic developments in a dynamic and heterogeneous clinical setting.

Immunosenescence and Cytomegalovirus: Exploring Their Connection in the Context of Aging, Health, and Disease

Aging induces numerous physiological alterations, with immunosenescence emerging as a pivotal factor. This phenomenon has attracted both researchers and clinicians, prompting profound questions about its implications for health and disease. Among the contributing factors, one intriguing actor in this complex interplay is human cytomegalovirus (CMV), a member of the herpesvirus family. Latent CMV infection exerts a profound influence on the aging immune system, potentially contributing to age-related diseases. This review delves into the intricate relationship between immunosenescence and CMV, revealing how chronic viral infection impacts the aging immune landscape. We explore the mechanisms through which CMV can impact both the composition and functionality of immune cell populations and induce shifts in inflammatory profiles with aging. Moreover, we examine the potential role of CMV in pathologies such as cardiovascular diseases, cancer, neurodegenerative disorders, COVID-19, and Long COVID. This review underlines the importance of understanding the complex interplay between immunosenescence and CMV. It offers insights into the pathophysiology of aging and age-associated diseases, as well as COVID-19 outcomes among the elderly. By unraveling the connections between immunosenescence and CMV, we gain a deeper understanding of aging's remarkable journey and the profound role that viral infections play in transforming the human immune system.

Human cytomegalovirus seropositivity is associated with reduced patient survival during sepsis

BACKGROUND

Sepsis is one of the leading causes of death. Treatment attempts targeting the immune response regularly fail in clinical trials. As HCMV latency can modulate the immune response and changes the immune cell composition, we hypothesized that HCMV serostatus affects mortality in sepsis patients.

METHODS

We determined the HCMV serostatus (i.e., latency) of 410 prospectively enrolled patients of the multicenter SepsisDataNet.NRW study. Patients were recruited according to the SEPSIS-3 criteria and clinical data were recorded in an observational approach. We quantified 13 cytokines at Days 1, 4, and 8 after enrollment. Proteomics data were analyzed from the plasma samples of 171 patients.

RESULTS

The 30-day mortality was higher in HCMV-seropositive patients than in seronegative sepsis patients (38% vs. 25%, respectively; p = 0.008; HR, 1.656; 95% CI 1.135-2.417). This effect was observed independent of age (p = 0.010; HR, 1.673; 95% CI 1.131-2.477). The predictive value on the outcome of the increased concentrations of IL-6 was present only in the seropositive cohort (30-day mortality, 63% vs. 24%; HR 3.250; 95% CI 2.075-5.090; p < 0.001) with no significant differences in serum concentrations of IL-6 between the two groups. Procalcitonin and IL-10 exhibited the same behavior and were predictive of the outcome only in HCMV-seropositive patients.

CONCLUSION

We suggest that the predictive value of inflammation-associated biomarkers should be re-evaluated with regard to the HCMV serostatus. Targeting HCMV latency might open a new approach to selecting suitable patients for individualized treatment in sepsis.

Effect of Cytomegalovirus Reactivation on Inflammatory Status and Mortality of Older COVID-19 Patients

Herpesviridae reactivation such as cytomegalovirus (CMV) has been described in severe COVID-19 (COronaVIrusDisease-2019). This study aimed to understand if CMV reactivation in older COVID-19 patients is associated with increased inflammation and in-hospital mortality. In an observational single-center cohort study, 156 geriatric COVID-19 patients were screened for CMV reactivation by RT-PCR. Participants underwent a comprehensive clinical investigation that included medical history, functional evaluation, laboratory tests and cytokine assays (TNF-α, IFN-α, IL-6, IL-10) at hospital admission. In 19 (12.2%) of 156 COVID-19 patients, CMV reactivation was detected. Multivariate Cox regression models showed that in-hospital mortality significantly increased among CMV positive patients younger than 87 years (HR: 9.94, 95% CI: 1.66–59.50). Other factors associated with in-hospital mortality were C-reactive protein (HR: 1.17, 95% CI: 1.05–1.30), neutrophil count (HR: 1.20, 95% CI: 1.01–1.42) and clinical frailty scale (HR:1.54, 95% CI: 1.04–2.28). In patients older than 87 years, neutrophil count (HR: 1.13, 95% CI: 1.05–1.21) and age (HR: 1.15, 95% CI: 1.01–1.31) were independently associated with in-hospital mortality. CMV reactivation was also correlated with increased IFN-α and TNF-α serum levels, but not with IL-6 and IL-10 serum changes. In conclusion, CMV reactivation was an independent risk factor for in-hospital mortality in COVID-19 patients younger than 87 years old, but not in nonagenarians.

A structured diagnostic algorithm for patients with ARDS

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2023. Other selected articles can be found online at  https://www.biomedcentral.com/collections/annualupdate2023 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from  https://link.springer.com/bookseries/8901 .

Association between active cytomegalovirus infection and lung fibroproliferation in adult patients with acute respiratory distress syndrome: a retrospective study

Background

Cytomegalovirus (CMV) has high seroprevalence, and its active infection is associated with several adverse prognoses in adult patients with acute respiratory distress syndrome (ARDS). However, the role of active CMV infection in ARDS-associated fibroproliferation is unknown. This study aimed at determining the association between active CMV infection and lung fibroproliferation in adult patients with ARDS.

Methods

We retrospectively reviewed the medical records of all adult patients with ARDS who were admitted to the intensive care unit (ICU) from January 2018 to December 2020 at a national university-affiliated hospital in China. Study subjects were divided into active and non-active CMV infection groups based on CMV DNAemia within a 28-day ICU hospitalization. Lung fibroproliferation was measured using chest high-resolution computed tomography (HRCT) and N-terminal peptide of serum procollagen III (NT-PCP-III) within the first 28 days of ICU admission. Pulmonary fibrosis, clinical features, laboratory findings, treatment measures, and clinical outcomes were compared between the two groups.

Results

Among the 87 ARDS patients included in this study, the incidence of active CMV infection was 16.1% within the 28-day ICU admission period. In logistic regression analyze, active CMV infection was found to be associated with higher pulmonary fibrogenesis, pulmonary fibrosis score, and NT-PCP-III level (P < 0.05). The duration of ICU stay in ARDS patients with active CMV infection was significantly higher than in those without active CMV infection (P < 0.05).

Conclusions

Among adult patients with ARDS, active CMV infection was related to poor clinical outcomes. Active CMV infection was associated with ARDS-associated fibroproliferation. Prophylactic and preemptive use of anti-CMV agents on pulmonary fibrosis should be assessed to determine a consensus therapeutic strategy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07747-y.

Role of released mitochondrial DNA in acute lung injury

Acute lung injury(ALI)/acute respiratory distress syndrome(ARDS) is a form of acute-onset hypoxemic respiratory failure characterised by an acute, diffuse, inflammatory lung injury, and increased alveolar-capillary permeability, which is caused by a variety of pulmonary or nonpulmonary insults. Recently, aberrant mitochondria and mitochondrial DNA(mtDNA) level are associated with the development of ALI/ARDS, and plasma mtDNA level shows the potential to be a promising biomarker for clinical diagnosis and evaluation of lung injury severity. In mechanism, the mtDNA and its oxidised form, which are released from impaired mitochondria, play a crucial role in the inflammatory response and histopathological changes in the lung. In this review, we discuss mitochondrial outer membrane permeabilisation (MOMP), mitochondrial permeability transition pore(mPTP), extracellular vesicles (EVs), extracellular traps (ETs), and passive release as the principal mechanisms for the release of mitochondrial DNA into the cytoplasm and extracellular compartments respectively. Further, we explain how the released mtDNA and its oxidised form can induce inflammatory cytokine production and aggravate lung injury through the Toll-like receptor 9(TLR9) signalling, cytosolic cGAS-stimulator of interferon genes (STING) signalling (cGAS-STING) pathway, and inflammasomes activation. Additionally, we propose targeting mtDNA-mediated inflammatory pathways as a novel therapeutic approach for treating ALI/ARDS.

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.

Reactivation of latent human cytomegaloviral infection in critically ill patients

Background & objectives

Human cytomegalovirus (HCMV) is a frequent participant in the infectious process in critically ill patients. This study aimed to determine the incidence of HCMV reactivation in critically ill patients and estimate the clinical effect of reactivation on the course of the pathological process.

Methods

To determine the incidence of HCMV reactivation, plasma and sputum samples were collected from 82 critically ill patients. HCMV reactivation was determined by quantitative PCR together with the presence of circulating HCMV IgG in the plasma. The statistical analysis of clinical data employed methods of descriptive (median with 95% confidence interval; minimum and maximum values, interquartile range) and nonparametric statistics [Mann-Whitney U test, odds ratio (OR), Kaplan-Meier survival analysis].

Results

HCMV reactivation was found in 36.6 per cent of cases. An association between the presence of sepsis and the development of HCMV reactivation (P<0.001), as well as higher HCMV viral loads in septic patients, was found. There was also an association between the presence of HCMV DNA and the subsequent development of sepsis (OR=1.504). The involvement of HCMV in the emerging immunological shifts manifested by a decrease in CD8+ T-lymphocytes (P=0.01) and an increase in the immunoregulatory index (P=0.03) was found.

Interpretation & conclusions

HCMV reactivation can influence the course of bacterial pathology with a deteriorating effect on such groups of patients. Monitoring the viral load of latent HCMV can be helpful in the assessment of the host immune status, the course of the pathological process, and its clinical prognosis.

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.

How Immunosenescence and Inflammaging May Contribute to Hyperinflammatory Syndrome in COVID-19

Aging is characterized by the dynamic remodeling of the immune system designated “immunosenescence,” and is associated with altered hematopoiesis, thymic involution, and lifelong immune stimulation by multitudinous chronic stressors, including the cytomegalovirus (CMV). Such alterations may contribute to a lowered proportion of naïve T-cells and to reduced diversity of the T-cell repertoire. In the peripheral circulation, a shift occurs towards accumulations of T and B-cell populations with memory phenotypes, and to accumulation of putatively senescent and exhausted immune cells. The aging-related accumulations of functionally exhausted memory T lymphocytes, commonly secreting pro-inflammatory cytokines, together with mediators and factors of the innate immune system, are considered to contribute to the low-grade inflammation (inflammaging) often observed in elderly people. These senescent immune cells not only secrete inflammatory mediators, but are also able to negatively modulate their environments. In this review, we give a short summary of the ways that immunosenescence, inflammaging, and CMV infection may cause insufficient immune responses, contribute to the establishment of the hyperinflammatory syndrome and impact the severity of the coronavirus disease 2019 (COVID-19) in elderly people.

Cytomegalovirus reactivation in immunocompetent mechanical ventilation patients: a prospective observational study

BACKGROUND

Cytomegalovirus (CMV) reactivation is associated with adverse prognoses of critically ill patients. However, the epidemiology and predictors of CMV reactivation in immunocompetent patients receiving mechanical ventilation (MV) are not clear. The aim of this study was to investigate the epidemiology and predictors of CMV reactivation in immunocompetent patients requiring MV.

METHODS

A single-center, prospective observational study (conducted from June 30, 2017 to July 01, 2018) with a follow-up of 90 days (September 29, 2018) that included 71 CMV-seropositive immunocompetent patients with MV at a 37-bed university hospital general intensive care unit (ICU) in China. Routine detection of CMV DNAemia was performed once a week for 28 days (Days 1, 7, 14, 21, and 28). CMV serology, laboratory findings, and clinical data were obtained during hospitalization.

RESULTS

Among 71 patients, 13 (18.3%) showed CMV reactivation within 28 days in the ICU. The median time to reactivation was 7 days. CMV reactivation was related to various factors, including body mass index (BMI), sepsis, N-terminal pro-b-type natriuretic peptide (NT-proBNP), blood urea nitrogen (BUN), and hemoglobin (Hb) levels (P < 0.05). In the multivariate regression model, BMI, Hb level, and sepsis were independently associated with CMV reactivation patients (P < 0.05). Moreover, the area under the receiver operating characteristic (AUROC) of BMI, Hb, and BMI combined with Hb was 0.69, 0.70, and 0.76, respectively. The duration of MV, hospitalization expense, length of ICU stay, and 90 day all-cause mortality rate in patients with CMV reactivation was significantly higher than in those without CMV reactivation (P < 0.05).

CONCLUSIONS

Among immunocompetent patients with MV, the incidence of CMV reactivation was 18.3%. CMV reactivation was associated with several adverse prognoses. BMI, Hb, and sepsis were independent risk factors for CMV reactivation. BMI and Hb may predict CMV reactivation.

Fatal cytomegalovirus pneumonia in a critically ill patient with COVID-19

Coronavirus disease 2019 (COVID-19) can cause severe lymphopenia and respiratory failure requiring prolonged invasive mechanical ventilation (MV). COVID-19 patients with severe lymphopenia or respiratory failure are at risk of developing secondary infections. Here, we present the needle autopsy findings of a critically ill patient with COVID-19 who required reintubation and prolonged MV, and eventually died of secondary cytomegalovirus (CMV) pneumonia. This case highlights the potential risk of long-term steroid use and the need for routine monitoring for CMV infection in critically ill patients with COVID-19.

Risk Factors for Cytomegalovirus Reactivation and Association With Outcomes in Critically Ill Adults With Sepsis: A Pooled Analysis of Prospective Studies

We performed multivariable analysis of potential risk factors (including cytomegalovirus [CMV] reactivation) for clinical outcomes by day 28 (death or continued hospitalization, ventilator-free days, intensive care unit (ICU)-free days, hospital-free days) from pooled cohorts of 2 previous prospective studies of CMV-seropositive adults with sepsis. CMV reactivation at any level, >100 IU/mL, >1000 IU/mL, peak viral load, and area under the curve were independently associated with the clinical outcomes. We identified the potential effect size of CMV on outcomes that could be used as end points for future interventional trials of CMV prevention using antiviral prophylaxis in ICU patients with sepsis.

Impact of antiviral treatment on long-term prognosis in non-immunocompromised patients with CMV reactivation

Background

Reactivation of human cytomegalovirus (CMV) occurs in non-immunocompromised patients with or without specific organ involvement, but it is still unknown whether it has a clinical implication on long-term prognosis or not.

Methods

A retrospective cohort study evaluating non-immunocompromised adult patients with CMV reactivation was conducted during the period between January 2010 and February 2018. Patients were divided into ganciclovir-treated and non-treated groups. Patients who died within 30 days from CMV reactivation were excluded as they died from complex causes of conditions. Survivors were followed for 30-months to evaluate long-term prognosis.

Results

A total of 136 patients with CMV reactivation was included, consisting of 66 ganciclovir-treated (48.5%) and 70 non-treated (51.5%) patients. Overall, patients were old-aged (median 70 years old) and most were treated with pneumonia of any cause (91.2%). More patients in ganciclovir-treated group were treated at intensive care unit (43.9% vs 24.3%, respectively) and had higher viral load over 5000 copies/ml (48.5% vs 22.9%) than non-treated group (all P < 0.05). Primary and secondary endpoints including 30-months survival (28.0 vs 38.9%, respectively) and 12-months survival (40.3% vs 49.2%) were not statistically different between the ganciclovir-treated and non-treated groups. In the multivariate analyses, ganciclovir treatment was not associated with 30-months survival (HR 1.307, 95% CI 0.759–2.251) and 12-months survival (HR 1.533, 95% CI 0.895–2.624).

Conclusion

In a retrospective cohort study evaluating non-immunocompromised patients with CMV reactivation, ganciclovir treatment was not associated with long-term prognosis. Antiviral treatment in this condition would not be necessary unless organ involvement is suspected.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06098-4.

Invasive pulmonary aspergillosis is associated with cytomegalovirus viremia in critically ill patients - A retrospective cohort study

BACKGROUND/PURPOSE

Cytomegalovirus (CMV) viremia is associated with a higher mortality rate and prolonged intensive care unit (ICU) stay for critically ill patients. CMV infection causes transient but substantial immunosuppression for transplant recipients, increasing risk of fungal infection. The association between CMV viremia and invasive pulmonary aspergillosis (IPA) for critically ill patients is still unknown.

METHODS

We retrospectively analyzed patients received bronchoalveolar lavage (BAL), galactomannan test, influenza survey and blood CMV viral load test in ICUs of a university hospital between April 2017 and May 2020. Independent risks for IPA were analyzed by multivariable logistic regression.

RESULTS

A total of 136 patients were included. Twenty-one patients had IPA, 48 patients had CMV viremia and 22 patients had influenza. In a multivariable logistic regression model, patients with CMV viremia or influenza had higher IPA risk (adjusted odds ratio, 3.98 and 8.72; 95% CI, 1.26-12.60 and 2.64-28.82; p value = 0.019 and <0.001, respectively.). Patients with detectable CMV in BAL fluid did not have higher IPA risk (crude odds ratio, 0.95; 95% CI, 0.33-2.79; p value = 0.933). After stratifying patients by CMV viral load, the IPA risk is higher for patients with higher viral loads. There is an additive synergistic effect on IPA risk between CMV viremia and influenza infection.

CONCLUSION

For critically ill patients, CMV viremia is an independent risk factor of IPA. Patients with higher blood CMV viral loads have a higher risk of IPA. CMV viremia and influenza have an additive synergistic effect for IPA risk in critically ill patients.

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).

Herpes simplex virus and Cytomegalovirus reactivation among severe ARDS patients under veno-venous ECMO

Background

Herpesviridae reactivation among non-immunocompromised critically ill patients is associated with impaired prognosis, especially during acute respiratory distress syndrome (ARDS). However, little is known about herpes simplex virus (HSV) and Cytomegalovirus (CMV) reactivation occurring in patients with severe ARDS under veno-venous extracorporeal membrane oxygenation (ECMO). We tried to determine the frequency of Herpesviridae reactivation and its impact on patients’ prognosis during ECMO for severe ARDS.

Results

During a 5-year period, 123 non-immunocompromised patients with a severe ARDS requiring a veno-venous ECMO were included. Sixty-seven patients (54%) experienced HSV and/or CMV reactivation during ECMO course (20 viral co-infection, 40 HSV alone, and 7 CMV alone). HSV reactivation occurred earlier than CMV after the beginning of MV [(6–15) vs. 19 (13–29) days; p < 0.01] and after ECMO implementation [(2–8) vs. 14 (10–20) days; p < 0.01]. In univariate analysis, HSV/CMV reactivation was associated with a longer duration of mechanical ventilation [(22–52.5) vs. 17.5 (9–28) days; p < 0.01], a longer duration of ECMO [15 (10–22.5) vs. 9 (5–14) days; p < 0.01], and a prolonged ICU [29 (19.5–47.5) vs. 16 (9–30) days; p < 0.01] and hospital stay [44 (29–63.5) vs. 24 (11–43) days; p < 0.01] as compared to non-reactivated patients. However, in multivariate analysis, viral reactivation remained associated with prolonged MV only. When considered separately, both HSV and CMV reactivation were associated with a longer duration of MV as compared to non-reactivation patients [29 (19.5–41) and 28 (20.5–37), respectively, vs. 17.5 (9–28) days; p < 0.05]. Co-reactivation patients had a longer duration of MV [58.5 (38–72.3); p < 0.05] and ICU stay [51.5 (32.5–69) vs. 27.5 (17.75–35.5) and 29 (20–30.5), respectively] as compared to patients with HSV or CMV reactivation alone. In multivariate analysis, HSV reactivation remained independently associated with a longer duration of MV and hospital length of stay.

Conclusions

Herpesviridae reactivation is frequent among patients with severe ARDS under veno-venous ECMO and is associated with a longer duration of mechanical ventilation. The direct causative link between HSV and CMV reactivation and respiratory function worsening under ECMO remains to be confirmed.

Cytomegalovirus-induced pathology in human temporal bones with congenital and acquired infection

OBJECTIVE

Publications on histopathology of human temporal bones with cytomegalovirus (CMV) infection are limited. We aim to determine histopathology of the inner ears and the middle ears in human temporal bones with congenital and acquired CMV infections.

METHODS

Temporal bones from 2 infants with congenital and 2 adults with acquired CMV infection were evaluated by light microscopy.

RESULTS

Two infants with congenital CMV infection showed striking pathological changes in the inner ear. There was a hypervascularization of the stria vascularis in the cochlea of the first infant, but no obvious loss of outer and inner hair cells was seen in the organ of Corti. However, cytomegalic cells and a loss of outer hair cells were found in the cochlea of the second infant. The vestibular organs of both infants showed cytomegalic cells, mostly located on dark cells. There was a loss of type I and type II hair cells in the macula of the saccule and utricle. Loss of hair cells and degeneration of nerve fibers was also seen in the semicircular canals. Both infants with congenital infection showed abundant inflammatory cells and fibrous structures in the middle ear cavity. No evidence of cytomegalic cells and hair cell loss was found in the cochlea or vestibular labyrinth in acquired CMV infection.

CONCLUSIONS

In two infants with congenital CMV infection, the cochlea, vestibule, and middle ear were highly affected. Temporal bones of adult donors with acquired viral infection showed histological findings similar to donors of the same age without ear disease.

A review of the use of time-varying covariates in the Fine-Gray subdistribution hazard competing risk regression model

In survival analysis, time‐varying covariates are covariates whose value can change during follow‐up. Outcomes in medical research are frequently subject to competing risks (events precluding the occurrence of the primary outcome). We review the types of time‐varying covariates and highlight the effect of their inclusion in the subdistribution hazard model. External time‐dependent covariates are external to the subject, can effect the failure process, but are not otherwise involved in the failure mechanism. Internal time‐varying covariates are measured on the subject, can effect the failure process directly, and may also be impacted by the failure mechanism. In the absence of competing risks, a consequence of including internal time‐dependent covariates in the Cox model is that one cannot estimate the survival function or the effect of covariates on the survival function. In the presence of competing risks, the inclusion of internal time‐varying covariates in a subdistribution hazard model results in the loss of the ability to estimate the cumulative incidence function (CIF) or the effect of covariates on the CIF. Furthermore, the definition of the risk set for the subdistribution hazard function can make defining internal time‐varying covariates difficult or impossible. We conducted a review of the use of time‐varying covariates in subdistribution hazard models in articles published in the medical literature in 2015 and in the first 5 months of 2019. Seven percent of articles published included a time‐varying covariate. Several inappropriately described a time‐varying covariate as having an association with the risk of the outcome.

Cytomegalovirus-associated acute respiratory failure in lupus patients: case reports in relation to cytomegalovirus biology

With the wide use of immunosuppressive agents, life-threatening cytomegalovirus-associated acute respiratory failure occurs frequently. However, this condition is yet to be fully recognized and the therapeutic approach to it can only be based on comprehensive protocols rather than the biological characteristics of cytomegalovirus. We describe three acute respiratory failure events that were related to the pathogenicity of cytomegalovirus, the primary cytopathic effect and secondary antiviral immunity-mediated damage. All cytomegalovirus infection occurred after immunosuppressive usage while the acute respiratory failure events took place in different clinical settings. The first acute respiratory failure event originated from the immunoinflammatory response after cytomegalovirus infection was circumscribed, while the second resulted from cytomegalovirus reactivation and the third was caused by the combined effect of acute cytomegalovirus infection and the subsequent immunoinflammatory response. According to the clinical setting, corresponding therapeutic approaches (sequential or combined strategy) were carried out. All the patients here presented were responsive to the above therapeutic strategies. Consequently, cytomegalovirus-associated acute respiratory failure in systemic lupus erythematosus patients should be carefully differentiated and a sequential or combined strategy should be carried out according to the clinical setting. Overall, we find that there are three patterns of cytomegalovirus-associated acute respiratory failure in systemic lupus erythematosus patients and propose a novel therapeutic strategy in relation to cytomegalovirus biology.

The Impact of Early Adequate Treatment on Extubation and Discharge Alive of Patients With Pseudomonas aeruginosa-Related Ventilator-Associated Pneumonia

OBJECTIVES

We aim to examine the effect of early adequate treatment in comparison with inadequate or delayed treatment on being extubated or discharged alive over time, in patients with Pseudomonas aeruginosa-related ventilator-associated pneumonia.

DESIGN

Retrospective analyses of a prospective observational multicenter cohort study.

SETTING

ICU.

PATIENTS

Patients of the French prospective database (OUTCOMEREA) were included if they acquired a ventilator-associated pneumonia due to P. aeruginosa between 1997 and 2014 and were mechanically ventilated for more than 48 hours.

INTERVENTIONS

Early adequate treatment in comparison with inadequate or delayed adequate treatment.

MEASUREMENTS AND MAIN RESULTS

Multistate models were applied to estimate the time-dependent probability of being extubated or discharged alive, and separate Cox regression analyses were used to assess the treatment effect on all important events that influence the outcome of interest. A propensity score-adjusted innovative regression technique was used for a combined and comprehensive patient-relevant summary effect measure. No evidence was found for a difference between adequate and inadequate or delayed treatment on being extubated or discharged alive. However, for all patients, the probability of being extubated or discharged alive remains low and does not exceed 50% even 40 days after a P. aeruginosa-related ventilator-associated pneumonia.

CONCLUSIONS

Early adequate treatment does not seem to be associated with an improved prognosis. Its potential benefit requires further investigation in larger observational studies.

Reactivation of Latent Cytomegalovirus Infection after Major Surgery: Risk Factors and Outcomes

Background: Reactivation of latent cytomegalovirus (CMV) infection occurs in previously immunocompetent critically ill individuals and may be associated with increased morbidity and mortality. Our aim was to explore risk factors for and outcomes after CMV reactivation in patients undergoing major surgery. Patients and Methods: We performed a retrospective case control study of patients without underlying immunocompromise who developed post-operative CMV reactivation from 2004-2016. Cases included patients testing positive for CMV by viral load, culture, or histopathology. Controls were matched by age, gender, type, and year of surgery. Results: Sixteen CMV cases were matched to 32 controls. Median age was 65 and median time from surgery to CMV diagnosis was 32 days. Symptoms included fever (94%), hepatitis (75%), myelosuppression (56%), and diarrhea (38%). Despite similar baseline comorbidities, cases were more likely to return to surgery (odds ratio [OR] 6.31; 95% confidence interval [CI], 1.29-30.74), require renal replacement therapy (OR 18.54; 95% CI, 2.36-145.6), total parenteral nutrition (OR 33.0; 95% CI, 6.60-262.37) and corticosteroids (OR 18.78; 95% CI, 4.5-103.9). Length of stay was increased (median 51 vs. 8 days, p = 0.005), co-infections were more common (OR 15.10; 95% CI, 1.89-120.8), and mortality was higher (38% vs. 0%, p < 0.01). Conclusions: Cytomegalovirus reactivation occurs in previously immunocomptent patients post-operatively and is associated with poor outcomes including other infections and mortality. Potential risk factors include prolonged length of stay, surgical complications, and corticosteroid use. It is not clear from our study whether CMV reactivation is a surrogate marker of severe illness and post-operative complications or if CMV reactivation plays a causative role in the development of these adverse outcomes.

The Third International Consensus Guidelines on the Management of Cytomegalovirus in Solid-organ Transplantation

Despite recent advances, cytomegalovirus (CMV) infections remain one of the most common complications affecting solid organ transplant recipients, conveying higher risks of complications, graft loss, morbidity, and mortality. Research in the field and development of prior consensus guidelines supported by The Transplantation Society has allowed a more standardized approach to CMV management. An international multidisciplinary panel of experts was convened to expand and revise evidence and expert opinion-based consensus guidelines on CMV management including prevention, treatment, diagnostics, immunology, drug resistance, and pediatric issues. Highlights include advances in molecular and immunologic diagnostics, improved understanding of diagnostic thresholds, optimized methods of prevention, advances in the use of novel antiviral therapies and certain immunosuppressive agents, and more savvy approaches to treatment resistant/refractory disease. The following report summarizes the updated recommendations.

Sepsis erodes CD8+ memory T cell-protective immunity against an EBV homolog in a 2B4-dependent manner

Epstein-Barr virus (EBV) reactivation commonly occurs following sepsis, but the mechanisms underlying this are unknown. We utilized a murine EBV homolog (gHV) and the cecal ligation and puncture model of polymicrobial sepsis to study the impact of sepsis on gHV reactivation and CD8⁺ T cell immune surveillance following a septic insult. We observed a significant increase in the frequency of gHV-infected germinal center B cells on day 7 following sepsis. This increase in viral load was associated with a concomitant significant decrease in the frequencies of gHV-specific CD8⁺ T cells, as measured by class I MHC tetramers corresponding to the immunodominant viral epitopes. Phenotypic analysis revealed an increased frequency of gHV-specific CD8⁺ T cells expressing the 2B4 coinhibitory receptor in septic animals compared with sham controls. We sought to interrogate the role of 2B4 in modulating the gHV-specific CD8⁺ T cell response during sepsis. Results indicated that in the absence of 2B4, gHV-specific CD8⁺ T cell populations were maintained during sepsis, and gHV viral load was unchanged in 2B4^-/- septic animals relative to 2B4^-/- sham controls. WT CD8⁺ T cells upregulated PD-1 during sepsis, whereas 2B4^-/- CD8⁺ T cells did not. Finally, adoptive transfer studies revealed a T cell-intrinsic effect of 2B4 coinhibition on virus-specific CD8⁺ T cells and gHV viral load during sepsis. These data demonstrate that sepsis-induced immune dysregulation erodes antigen-specific CD8⁺ responses against a latent viral infection and suggest that blockade of 2B4 may better maintain protective immunity against EBV in the context of sepsis.

Effect of cytomegalovirus reactivation on the time course of systemic host response biomarkers in previously immunocompetent critically ill patients with sepsis: a matched cohort study

BACKGROUND

Cytomegalovirus (CMV) reactivation in previously immunocompetent critically ill patients is associated with increased mortality, which has been hypothesized to result from virus-induced immunomodulation. Therefore, we studied the effects of CMV reactivation on the temporal course of host response biomarkers in patients with sepsis.

METHODS

In this matched cohort study, each sepsis patient developing CMV reactivation between day 3 and 17 (CMV+) was compared with one CMV seropositive patient without reactivation (CMVs+) and one CMV seronegative patient (CMVs-). CMV serostatus and plasma loads were determined by enzyme-linked immunoassays and real-time polymerase chain reaction, respectively. Systemic interleukin-6 (IL-6), IL-8, IL-18, interferon-gamma-induced protein-10 (IP-10), neutrophilic elastase, IL-1 receptor antagonist (RA), and IL-10 were measured at five time points by multiplex immunoassay. The effects of CMV reactivation on sequential concentrations of these biomarkers were assessed in multivariable mixed models.

RESULTS

Among 64 CMV+ patients, 45 could be matched to CMVs+ or CMVs- controls or both. The two baseline characteristics and host response biomarker levels at viremia onset were similar between groups. CMV+ patients had increased IP-10 on day 7 after viremia onset (symmetric percentage difference +44% versus -15% when compared with CMVs+ and +37% versus +4% when compared with CMVs-) and decreased IL-1RA (-41% versus 0% and -49% versus +10%, respectively). However, multivariable analyses did not show an independent association between CMV reactivation and time trends of IL-6, IP-10, IL-10, or IL-1RA.

CONCLUSION

CMV reactivation was not independently associated with changes in the temporal trends of host response biomarkers in comparison with non-reactivating patients. Therefore, these markers should not be used as surrogate clinical endpoints for interventional studies evaluating anti-CMV therapy.

Expression of human miR-200b-3p and -200c-3p in cytomegalovirus-infected tissues

Human cytomegalovirus (HCMV) infection can cause inflammatory tissue-invasive end-organ diseases upon lytic replication. In humans, mature miR-200b-3p and -200c-3p suppress the synthesis of HCMV immediate early 2 (IE2) protein by binding to the 3′-UTR of the mRNA encoded by the unique long (UL) 122-123 region in human foreskin fibroblasts and pre-transplant peripheral blood mononuclear cells stimulated with HCMV. The present study aimed to quantitate the expression of Homo sapiens (hsa)-miR-200b-3p and 200c-3p in HCMV-infected tissues. We collected 240 HCMV-infected and 154 HCMV-non-infected, formalin-fixed, paraffin-embedded tissue samples of the gastrointestinal (GI) tract and bronchi/lungs. MiRNAs, HCMV, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) were quantitated by quantitative reverse transcription-PCR (qRT-PCR) and quantitative PCR (qPCR) on the basis of standard curves generated using miRNA mimics, the HCMV strain from National Institute for Biological Standards and Control (NIBSC) 09/162, and GAPDH control. To avoid the effect of cell counts on the qRT-PCR and qPCR results, the data were normalized to GAPDH levels. HCMV-infected tissues had significantly lower levels of 200b-3p/GAPDH (3.03 ± 1.50 compared with 3.98 ± 1.08 log₁₀ copies/μl, P<0.001) and 200c-3p/GAPDH (4.67 ± 1.84 compared with 6.35 ± 1.47 log₁₀ copies/μl, P<0.001) than normal tissues. The values for 200b-3p/GAPDH (r = −0.51, P<0.001) and 200c-3p/GAPDH (r = −0.54, P<0.001) were significantly inversely correlated with HCMV load. Low tissue levels of 200b-3p and 200c-3p in humans are associated with cytopathic inflammation due to HCMV infection.

Comparison of universal prophylaxis and preemptive approach for cytomegalovirus associated outcome measures in renal transplant patients: A meta-analysis of available data

Cytomegalovirus (CMV) is a ubiquitous latent human virus that often causes complications in renal transplantation recipients. Universal prophylaxis and preemptive therapy are alternative strategies to prevent CMV associated complications. This meta-analysis aimed to assess available data comparing the effectiveness of prophylaxis and preemptive therapy for preventing adverse outcomes. We searched the PubMed, Ovid, Web of Science, Cochrane Library, and Open Grey databases using a combination of keywords. Random effects models along with the Paule-Mandel estimator were used to synthesize pooled effect estimates. Eleven studies were eligible for the final analysis. Universal prophylaxis was better at preventing CMV disease than the preemptive approach (risk difference = -0.0459; confidence intervals = -0.0791, -0.0127; P-value = 0.0067; number needed to treat [NNT] = 22 [1/0.0459]; high, 79 [1/0.0127] patients; low, 13 [1/0.0791] patients). Subgroup analysis revealed a more consistent effect among studies published after 2010, with negligible between-study heterogeneity. The NNT for universal prophylaxis to prevent one excess CMV disease concerning preemptive therapy was 16 (1/0.0630) patients (high, 25 [1/0.0394]; low, 12 [1/0.0867] patients) in the subgroup of studies performed after 2010. We detected no significant difference between the two strategies regarding acute rejection and graft loss, with negligible variability due to heterogeneity between studies. Although universal prophylaxis performed better than the preemptive strategy for the prevention of CMV disease, the high NNT value may discourage the use of CMV prophylaxis. Since there were no differences between the strategies concerning acute rejection and graft loss, this study supports the use of the preemptive approach as an alternative to universal prophylaxis.

Cytomegalovirus infection and outcome in immunocompetent patients in the intensive care unit: a systematic review and meta-analysis

BACKGROUND

Cytomegalovirus (CMV) infection is common in immunocompetent patients in intensive care units (ICUs). However, whether CMV infection or CMV reactivation contributes to mortality of immunocompetent patients remains unclear.

METHODS

A literature search was conducted for relevant studies published before May 30, 2016. Studies reporting on CMV infection in immunocompetent patients in ICUs and containing 2 × 2 tables on CMV results and all-cause mortality were included.

RESULTS

Eighteen studies involving 2398 immunocompetent patients admitted to ICUs were included in the meta-analysis. The overall rate of CMV infection was 27% (95%CI 22-34%, I² = 89%, n = 2398) and the CMV reactivation was 31% (95%CI 24-39%, I² = 74%, n = 666). The odds ratio (OR) for all-cause mortality among patients with CMV infection, compared with those without infection, was 2.16 (95%CI 1.70-2.74, I² = 10%, n = 2239). Moreover, upon exclusion of studies in which antiviral treatment was possibly or definitely provided to some patients, the association of mortality rate with CMV infection was also statistically significant (OR: 1.69, 95%CI 1.01-2.83, I² = 37%, n = 912,). For CMV seropositive patients, the OR for mortality in patients with CMV reactivation as compared with patients without CMV reactivation was 1.72 (95%CI 1.04-2.85, I² = 29%, n = 664). Patients with CMV infection required significantly longer mechanical ventilation (mean difference (MD): 9 days (95% CI 5-14, I² = 81%, n = 875)) and longer duration of ICU stay (MD: 12 days (95% CI 7-17, I² = 70%, n = 949)) than patients without CMV infection. When analysis was limited to detection in blood, CMV infection without antiviral drug treatment or reactivation was not significantly associated with higher mortality (OR: 1.69, 95%CI 0.81-3.54, I² = 52%, n = 722; OR: 1.49, I² = 63%, n = 469).

CONCLUSION

Critically ill patients without immunosuppression admitted to ICUs show a high rate of CMV infection. CMV infection during the natural unaltered course or reactivation in critically ill patients is associated with increased mortality, but have no effect on mortality when CMV in blood. More studies are needed to clarify the impact of CMV infection on clinical outcomes in those patients.

Epidemiology of Multiple Herpes Viremia in Previously Immunocompetent Patients With Septic Shock

Background

Systemic reactivations of herpesviruses may occur in intensive care unit (ICU) patients, even in those without prior immune deficiency. However, the clinical relevance of these events is uncertain.

Methods

In this study we selected patients admitted with septic shock and treated for more than 4 days from a prospectively enrolled cohort of consecutive adults in the mixed ICUs of 2 tertiary care hospitals in the Netherlands. We excluded patients who had received antiviral treatment in the week before ICU admission and those with known immunodeficiency. We studied viremia episodes with cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), and varicella zoster virus (VZV) by weekly polymerase chain reaction in plasma.

Results

Among 329 patients, we observed 399 viremia episodes in 223 (68%) patients. Viremia with CMV, EBV, HHV-6, HSV-1, HSV-2, and VZV was detected in 60 (18%), 157 (48%), 80 (24%), 87 (26%), 13 (4%), and 2 (0.6%) patients, respectively; 112 (34%) patients had multiple concurrent viremia events. Crude mortality in the ICU was 36% in this latter group compared to 19% in remaining patients (P < .01). After adjustment for potential confounders, time-dependent bias, and competing risks, only concurrent CMV and EBV reactivations remained independently associated with increased mortality (adjusted subdistribution hazard ratio, 3.17; 95% confidence interval, 1.41-7.13).

Conclusions

Herpesvirus reactivations were documented in 68% of septic shock patients without prior immunodeficiency and frequently occurred simultaneously. Concurrent reactivations could be independently associated with mortality.

Clinical Trials Registration

NCT01905033.

Advances in the understanding and treatment of sepsis-induced immunosuppression

Sepsis is defined as a life-threatening organ dysfunction that is caused by a dysregulated host response to infection. Sepsis can induce acute kidney injury and multiple organ failures and represents the most common cause of death in the intensive care unit. Sepsis initiates a complex immune response that varies over time, with the concomitant occurrence of both pro-inflammatory and anti-inflammatory mechanisms. As a result, most patients with sepsis rapidly display signs of profound immunosuppression, which is associated with deleterious consequences. Scientific advances have highlighted the role of metabolic failure, epigenetic reprogramming, myeloid-derived suppressor cells, immature suppressive neutrophils and immune alterations in primary lymphoid organs (the thymus and bone marrow) in sepsis. An improved understanding of the mechanisms underlying this immunosuppression as well as of the similarities between sepsis-induced immunosuppression and immune defects in cancer or immunosenescence has led to novel therapeutic strategies aimed at stimulating immune function in patients with sepsis. Trials assessing the therapeutic benefit of IL-7, granulocyte-macrophage colony-stimulating factor (GM-CSF) and antibodies against programmed cell death protein 1 (PD1) and programmed cell death 1 ligand 1 (PDL1) for the treatment of sepsis are in progress. The reappraisal of sepsis pathophysiology has also resulted in a novel approach to the design of clinical trials evaluating sepsis treatments, based on an evaluation of the immune status and biomarker-based stratification of patients.

Effect of Ganciclovir on IL-6 Levels Among Cytomegalovirus-Seropositive Adults With Critical Illness: A Randomized Clinical Trial

IMPORTANCE

The role of cytomegalovirus (CMV) reactivation in mediating adverse clinical outcomes in nonimmunosuppressed adults with critical illness is unknown.

OBJECTIVE

To determine whether ganciclovir prophylaxis reduces plasma interleukin 6 (IL-6) levels in CMV-seropositive adults who are critically ill.

DESIGN, SETTING, AND PARTICIPANTS

Double-blind, placebo-controlled, randomized clinical trial (conducted March 10, 2011-April 29, 2016) with a follow-up of 180 days (November 10, 2016) that included 160 CMV-seropositive adults with either sepsis or trauma and respiratory failure at 14 university intensive care units (ICUs) across the United States.

INTERVENTIONS

Patients were randomized (1:1) to receive either intravenous ganciclovir (5 mg/kg twice daily for 5 days), followed by either intravenous ganciclovir or oral valganciclovir once daily until hospital discharge (n = 84) or to receive matching placebo (n = 76).

MAIN OUTCOMES AND MEASURES

The primary outcome was change in IL-6 level from day 1 to 14. Secondary outcomes were incidence of CMV reactivation in plasma, mechanical ventilation days, incidence of secondary bacteremia or fungemia, ICU length of stay, mortality, and ventilator-free days (VFDs) at 28 days.

RESULTS

Among 160 randomized patients (mean age, 57 years; women, 43%), 156 patients received 1or more dose(s) of study medication, and 132 patients (85%) completed the study. The mean change in plasma IL-6 levels between groups was -0.79 log10 units (-2.06 to 0.48) in the ganciclovir group and -0.79 log10 units (-2.14 to 0.56) in the placebo group (point estimate of difference, 0 [95% CI, -0.3 to 0.3]; P > .99). Among secondary outcomes, CMV reactivation in plasma was significantly lower in the ganciclovir group (12% [10 of 84 patients] vs 39% [28 of 72 patients]); absolute risk difference, -27 (95% CI, -40 to -14), P < .001. The ganciclovir group had more median VFDs in both the intention-to-treat (ITT) group and in the prespecified sepsis subgroup (ITT group: 23 days in ganciclovir group vs 20 days in the placebo group, P = .05; sepsis subgroup, 23 days in the ganciclovir group vs 20 days in the placebo group, P = .03). There were no significant differences between the ganciclovir and placebo groups in duration of mechanical ventilation (5 days for the ganciclovir group vs 6 days for the placebo group, P = .16), incidence of secondary bacteremia or fungemia (15% for the ganciclovir group vs 15% for the placebo group, P = .67), ICU length of stay (8 days for the ganciclovir group vs 8 days for the placebo group, P = .76), or mortality (12% for the ganciclovir group vs 15% for the placebo group, P = .54).

CONCLUSIONS AND RELEVANCE

Among CMV-seropositive adults with critical illness due to sepsis or trauma, ganciclovir did not reduce IL-6 levels and the current study does not support routine clinical use of ganciclovir as a prophylactic agent in patients with sepsis. Additional research is necessary to determine the clinical efficacy and safety of CMV suppression in this setting.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01335932.

Multistate Modeling to Analyze Nosocomial Infection Data: An Introduction and Demonstration

OBJECTIVE Multistate and competing risks models have become an established and adequate tool with which to quantify determinants and consequences of nosocomial infections. In this tutorial article, we explain and demonstrate the basics of these models to a broader audience of professionals in health care, infection control, and hospital epidemiology. METHODS Using a publicly available data set from a cohort study of intensive care unit patients, we show how hospital infection data can be displayed and explored graphically and how simple formulas are derived under some simplified assumptions for illustrating the basic ideas behind multistate models. Only a few simply accessible values (event counts and patient days) and a pocket calculator are needed to reveal basic insights into cumulative risk and clinical outcomes of nosocomial infection in terms of mortality and length of stay. RESULTS We show how to use these values to perform basic multistate analyses in own data or to correct biased estimates in published data, as these values are often reported. We also show relationships between multistate-based hazard ratios and odds ratios, which are derived from the popular logistic regression model. CONCLUSIONS No sophisticated statistical software is required to apply a basic multistate model and to avoid typical pitfalls such as time-dependent or competing-risks bias. Infect Control Hosp Epidemiol 2017;38:953-959.