Active cytomegalovirus infection in patients with septic shock

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.

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.

Update on the risk assessment of a rehabilitation stay for patients after allogeneic stem cell transplantation

OBJECTIVE

High-dose chemotherapy with allogeneic stem cell transplantation is the only chance of cure for many haemato-oncological patients. After such therapy, the immune system is weakened, and the contact with other people should therefore be limited as much as possible. The question arises whether a rehabilitation stay can be recommended to these patients, which risk factors for complications during the rehabilitation stay can be identified, and whether physicians and patients can be provided with decision-making aids as to when the optimal time is to start rehabilitation.

METHODS

We report about 161 rehabilitation stays of patients after high-dose chemotherapy with allogeneic stem cell transplantation. Premature discontinuation of the rehabilitation was selected as the criterion for a serious complication during the rehabilitation and the underlying reasons were analysed.

RESULTS

The rate of prematurely terminated rehabilitation stays (13.6%) corresponds to our previous result from 2020. The analysis of the reasons for early termination comes to the conclusion that the rehabilitation stay is only considered as a reason for termination in very few cases, if at all. The risk factors identified for premature termination of the rehabilitation stay were male sex, the period (days) between transplantation and the beginning of the rehabilitation stay, haemoglobin value, platelets and presence of immunosuppressing agent. The most significant risk factor is a decreased platelet count at the time rehabilitation begins. The platelet count, the likelihood that it will improve in the further course and the urgency of the rehabilitation stay can be used to help decide when the optimal time for rehabilitation is given.

CONCLUSION

Rehabilitation can be recommended to patients after allogeneic stem cell transplantation. Based on various factors, recommendations can be made for the right time for rehabilitation.

Analysis of the effect of cytomegalovirus infection in clinical outcomes and prolonged duration of SARS-CoV-2 shedding in intensive care unit patients with COVID-19 pneumonia

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a global outbreak disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Cytomegalovirus (CMV) infection can occur in critical COVID-19 patients and is associated with adverse clinical outcomes.

OBJECTIVE

The aim of this study was to explore the clinical characteristics and outcome of CMV infection in critical COVID-19 patients.

DESIGN

This was a retrospective cohort study.

METHODS

From May to September 2021, SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR)-confirmed COVID-19 patients with intensive care unit (ICU) admission were enrolled. CMV infection was confirmed by PCR. Baseline characteristics, critical illness data and clinical outcomes were recorded and analyzed.

RESULTS

Seventy-two RT-PCR-confirmed COVID-19 patients with ICU admission were included during the study period and 48 (66.7%) patients required mechanical ventilation (MV). Overall, in-hospital mortality was 19.4%. Twenty-one (29.2%) patients developed CMV infection. Patients with CMV infection had a higher likelihood of diabetes, higher lactate dehydrogenase and lactate levels, and higher proportions of MV, anticoagulant, and steroid use. Patients with CMV infection were associated with longer duration of SARS-CoV-2 shedding, longer ICU and hospital stay, and fewer ventilator-free days. The independent risk factor for development of CMV infection was a higher accumulative steroid dose.

CONCLUSION

CMV infection adversely impacted the outcomes of critical COVID-19 patients, resulting in longer ICU stays, longer mechanical ventilation uses and prolonged shedding of SARS-CoV-2.

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.

Disulfiram attenuates MCMV-Induced pneumonia by inhibition of NF-κB/NLRP3 signaling pathway in immunocompromised mice

Cytomegalovirus (CMV) pneumonia in immunocompromised individuals is associated with damaging hyperinflammation and leads to high morbidity and mortality. It is urgently needed to develop new strategies to treat CMV-induced pneumonia. As disulfiram (DSF) reportedly inhibits inflammatory responses in different disease models, its therapeutic effects in CMV-induced pneumonia are proposed. In this study, we demonstrated that DSF effectively attenuated pulmonary injury and improved survival in murine CMV (MCMV) pneumonia model. DSF treatment inhibited lung inflammatory responses, e.g. reducing pro-inflammatory cytokines, upregulating anti-inflammatory cytokine, and lowering the accumulation of leukocytes in the lung. Similar to the in vivo results, DSF attenuated inflammatory responses and modulated NF-κB/NLRP3 inflammasome activation in MCMV-infected BMDMs. Furthermore, DSF reduced pulmonary fibrosis and viral loads in MCMV pneumonia mice and BMDMs. The mechanism of anti-inflammatory effects of DSF may due to its regulating NF-κB signaling and NLRP3 inflammasome activation. Collectively, our results suggest that DSF-mediated anti-hyperinflammatory effects have potentials for therapy of human CMV pneumonia.

Cytomegalovirus Cholangiopathy in an Immunocompetent Patient: A Case Report and Literature Review

A 37-year-old man presented with jaundice, upper right quadrant pain, and intermittent fever with chills. Laboratory assessment showed biliary stasis, with total bilirubin of 203 µmol/L (2–20), conjugated bilirubin of 105 µmol/L, and alkaline phosphatase of 556 U/L (30–120). Markers for hepatitis A–E viruses were negative. Serology assessment for rubeola, herpes simplex virus, Epstein-Barr virus, and Toxoplasma gondii showed negative IgM antibodies. HIV serology status was negative. For cytomegalovirus, both types of antibodies (IgM and IgG) were positive, with an IgM level >300 U/mL. pp65 antigen was also detected as well as CMV DNA. Diagnostic imaging of the abdomen except the dilated common bile duct showed a normal appearance of the gallbladder, liver, pancreas, spleen, and both kidneys. To our knowledge, cytomegalovirus cholangiopathy in the absence of any other underlying disease has not been reported. Therefore, the presence of cholangiopathy in our patient is interesting from an imaging, laboratory, and clinical point of view.

Impact of cytomegalovirus reactivation just before liver transplantation: A prospective cohort study

BACKGROUND

Cytomegalovirus (CMV) is the most common viral pathogen after liver transplantation (LT). Although reactivation of CMV infection is generally described in the context of immunosuppression, it has also been described in critically ill immunocompetent patients including cirrhotic patients.

AIM

To determine the incidence of reactivated CMV prior to LT.

METHODS

This was a prospective cohort study evaluating adult patients who underwent LT between 2014 and 2016. A plasma sample was obtained from all patients for CMV quantitative real-time PCR testing right before transplantation. Patients were followed for at least 1 year to assess the following outcomes: Incidence of CMV infection, organ rejection and overall mortality.

RESULTS

A total of 72 patients were enrolled. Four patients died before transplantation, thus 68 patients were followed up for a median of 44 mo (20-50 mo). In 23/72 patients (31.9%) CMV was reactivated before transplantation. Post-transplantation, 16/68 (23.5%) patients had CMV infection and that was significantly associated with the recipient being CMV negative and a CMV-positive donor. Pre-transplant CMV reactivation was not associated with overall mortality (log rank: 0.9).

CONCLUSION

This study shows that CMV infection is common in patients with chronic liver disease just before LT, but the clinical impact of this infection seems to be negligible.

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.

Cytomegalovirus pancreatitis in an immunocompetent patient

Cytomegalovirus (CMV) is a double-stranded DNA virus, which infects a large portion of the adult population. In immunocompetent patients, it typically is asymptomatic or manifests as mild and self-limiting flu-like illness symptoms, whereas in immunocompromised patients, CMV can cause significant disease. Herein we report an unusual case of CMV pancreatitis in an immunocompetent 75-year-old female. Patient developed severe significant pancreatic necrosis that failed non-operative management, and ultimately underwent pancreatic necrosectomy. Later on, she developed three spontaneous gastric perforations. The first two perforations were managed operatively, but after the third perforation family decided not to undergo another operation. The CMV pancreatitis diagnosis was based on pancreatic histopathology and confirms by a prompt response to ganciclovir. Patient was promptly started on intravenous (IV) ganciclovir which resulted in clinical recovery and she remained asymptomatic more than one-year post op. This is a rare case of CMV pancreatitis with gastric perforations in an immunocompetent patient. High degree of suspicion and appropriate treatment are important for such clinical scenarios.

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.

Reactivation Viremia in Pediatric Sepsis

OBJECTIVES

Reactivation viremia is associated with adverse clinical outcomes and immune dysfunction in adults with sepsis. We determined the incidence of viremia and its association with clinical outcomes and immune paralysis phenotype in children with severe sepsis.

DESIGN

Prospective cohort study.

SETTING

Single academic PICU from September 2016 to March 2018.

PATIENTS

Fifty-nine patients 2-17 years old treated for severe sepsis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We performed real-time polymerase chain reaction assays on whole blood specimens to determine the incidence of cytomegalovirus. Cytomegalovirus was detected in three patients (5%). All patients with cytomegalovirus viremia were seropositive, with an incidence of 13% in this subset. We additionally performed Epstein-Barr virus and human herpesvirus-6 polymerase chain reaction assays on last available specimens and detected Epstein-Barr virus in 4% and human herpesvirus-6 in 30% of the study population. Overall, viremia was not associated with clinical outcomes or immune function in univariable analyses. However, viremia was associated with lower odds of complicated course (defined as death within 28 d or ≥ 2 organ dysfunctions at 7 d) after controlling for age, Pediatric Risk of Mortality III score, and blood transfusion (adjusted odds ratio, 0.08; 95% CI, 0.01-0.84; p = 0.04).

CONCLUSIONS

Children with severe sepsis had low rates of detectable viremia, which limited analyses of its association with clinical outcomes or immune paralysis phenotype. Given the rare occurrence of cytomegalovirus viremia, in particular, our study does not support a role for viremia as a biomarker of illness severity or as a modifiable risk factor of clinical outcomes for most patients. Future studies on the role of viremia in pediatric sepsis will need to consider the challenges posed by low rates of viremia in this population.

Diagnosis of human cytomegvirus association with malignant gliomas and pro- and anti-inflammatories

The study was conducted on seventy individuals of both genders who have been exposed to human cytomegalovirus, a common illness in Iraq. Total cases of human cytomegvirus associated with malignant brain tumors were detected by a real time PCR technique. This resulted in only thirty-six cases of true infection. Of these 24 cases were female, while 12 cases of male infected. The titer to assay the presence of anti- and pro-inflammatories was assessed in sera of all patients by using ELISA kits to evaluate cytokines. This indicated that the pro-inflammatory IL12, after seven days increased (1.67±0.23 pg/ml), while IL4, an anti-inflammatory, decreased to reach (0.39±0.16 pg/ml) (at p<0.05) in the plasm of the experimental patients compared with the control group.

Does rehabilitation pose a risk to patients suffering from haemato-oncological diseases? Results of a monocentric, retrospective analysis in Germany

OBJECTIVE

Patients suffering from haemato-oncological diseases tend to have a weakened immune system after the end of their therapy. To avoid infections, patients are advised to limit contact with other people. This poses the question whether a stay at a rehabilitation facility can be recommended.

METHODS

We report about 134 rehabilitation stays of patients. Premature discontinuation of the rehabilitation stay was selected as the criterion for a serious complication during the rehabilitation, and the underlying reasons were analysed.

RESULTS

Compared to the discontinuation rates of patients suffering from solid tumours (2.4%), the percentage of haemato-oncological patients ending prematurely their rehabilitation stay (8.2%) is significantly increased. This rises to 17.1% for patients who have undergone an allogeneic stem cell transplantation. The analysis of the discontinuation reasons revealed that they were not directly connected to the rehabilitation. Apart from the already known risk factors for premature termination of the rehabilitation stay, we have identified the period (days) between the last therapy and the beginning of the rehabilitation stay as a risk factor.

CONCLUSIONS

We show for the first time that a rehabilitation stay does not pose additional risks for patients suffering from haemato-oncological diseases.

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.

Impaired polyfunctionality of CD8+ T cells in severe sepsis patients with human cytomegalovirus reactivation

Human cytomegalovirus (HCMV) establishes a lifelong chronic latent infection and often reactivates in immunocompromised patients. In addition, HCMV reactivates in patients with sepsis or other critical illnesses, particularly in patients with poor prognoses. However, the immunological characteristics of sepsis patients with HCMV reactivation have not been elucidated. In the present study, we examined T-cell responses in severe sepsis patients with and without HCMV reactivation. First, HCMV pp65-specific T-cell functions were assessed by intracellular cytokine staining (ICS) for IFN-γ, TNF-α, and MIP-1β and by CD107a staining. We analyzed the ICS data for each function individually and found no difference between the patient groups. However, the relative frequency of polyfunctional CD8⁺ T cells was significantly decreased in sepsis patients with HCMV reactivation. Next, we examined programmed cell death protein 1 (PD-1) expression. It was significantly increased in the CD8⁺ T-cell population in severe sepsis patients with HCMV reactivation, indicating CD8⁺ T-cell exhaustion. Interestingly, the frequency of PD-1⁺ cells in the CD8⁺ T-cell population was inversely correlated with the relative frequency of polyfunctional CD8⁺ T cells. Herein, we demonstrate that HCMV reactivation in severe sepsis patients is associated with PD-1 expression and impaired polyfunctionality of CD8⁺ T cells.

Safety and Efficacy of Antiviral Therapy for Prevention of Cytomegalovirus Reactivation in Immunocompetent Critically Ill Patients: A Randomized Clinical Trial

IMPORTANCE

Latent cytomegalovirus (CMV) infection is present in more than half the adult population, and a viral reactivation (ie, when the virus becomes measurable in body fluids such as blood) can occur in up to one-third of these individuals during episodes of critical illness.

OBJECTIVE

To determine whether antiviral therapy is safe and effective for preventing CMV reactivation in a general population of critically ill patients.

DESIGN, SETTING, AND PARTICIPANTS

A single-center, open-label, randomized, controlled clinical trial recruited 124 CMV-seropositive patients undergoing mechanical ventilation for at least 24 hours in the intensive care unit between January 1, 2012, and January 31, 2014. The mean baseline Acute Physiology and Chronic Health Evaluation II score of all patients was 17.6.

INTERVENTIONS

Patients were randomized to receive anti-CMV prophylaxis with valacyclovir hydrochloride (n = 34) or low-dose valganciclovir hydrochloride (n = 46) for up to 28 days to suppress viral reactivation, or to a control group with no intervention (n = 44).

MAIN OUTCOMES AND MEASURES

Time to first CMV reactivation in blood within the 28-day follow-up period following initiation of the study drug.

RESULTS

Among the 124 patients in the study (46 women and 78 men; mean [SD] age, 56.9 [16.9] years), viral reactivation in the blood occurred in 12 patients in the control group, compared with 1 patient in the valganciclovir group and 2 patients in the valacyclovir group (combined treatment groups vs control: hazard ratio, 0.14; 95% CI 0.04-0.50). Although this trial was not powered to assess clinical end points, the valacyclovir arm was halted prematurely because of higher mortality; 14 of 34 patients (41.2%) had died by 28 days, compared with 5 of 37 (13.5%) patients in the control arm at the point of the decision to halt this arm. Other safety end points showed similar outcomes between groups.

CONCLUSIONS AND RELEVANCE

Antiviral prophylaxis with valacyclovir or low-dose valganciclovir suppresses CMV reactivation in patients with critical illness. However, given the higher mortality, a large-scale trial would be needed to determine the clinical efficacy and safety of CMV suppression.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01503918.

Inflammasome expression and cytomegalovirus viremia in critically ill patients with sepsis

BACKGROUND

CMV viremia is a contributor to poor outcomes in critically ill patients with sepsis.

OBJECTIVES

To assess the expression levels of genes encoding inflammasome-related proteins in the development of CMV viremia in critically ill patients with sepsis.

STUDY DESIGN

A cohort of CMV-seropositive critically ill patients with sepsis due to bloodstream infection underwent weekly testing for CMV viremia. Blood samples to evaluate mRNA levels of genes encoding CASP1, ASC, NLRP1, NLRP3, and NLRP12 were collected at the time of enrollment. Clinical outcomes were assessed at 30days or until death/discharge from ICU.

RESULTS

CMV viremia was documented in 27.5% (8/29) of the patients, a median of 7days after the onset of bacteremia. Patients with sepsis who developed CMV viremia had higher CASP1 although this was not statistically significant (relative mean 3.6 vs 1.8, p=0.13). Development of high grade CMV viremia however, was significantly associated with CASP1; septic patients who developed high grade CMV viremia had significantly higher CASP1than all other patients (relative mean 5.5 vs 1.8, p=0.016).

CONCLUSIONS

These data document possible involvement of inflammasome in the pathogenesis of CMV. Regulating the host immune response by agents that target these genes may have implications for improving CMV-related outcomes in these patients.

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 immunocompetent critically ill adults: literature review

Cytomegalovirus (CMV) infection is increasingly recognized in critically ill immunocompetent patients. Some studies have demonstrated an association between CMV disease and increased mortality rates, prolonged intensive care unit and hospital length of stay, prolonged mechanical ventilation, and nosocomial infections. However, there is a considerable controversy whether such association represents a causal relationship between CMV disease and unfavorable outcomes or just a marker of the severity of the critical illness. Detection of CMV using polymerase chain reaction and CMV antigenemia is the standard diagnostic approach. CMV may have variety of clinical manifestations reflecting the involvement of different organ systems. Treatment of CMV in critical care is challenging due to diagnostic challenge and drug toxicity, and building predictive model for CMV disease in critical care setting would be promising to identify patients at risk and starting prophylactic therapy. Our objective was to broadly review the current literature on the prevalence and incidence, clinical manifestations, potential limitations of different diagnostic modalities, prognosis, and therapeutic options of CMV disease in critically ill patients.

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.

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.

Human herpesviruses respiratory infections in patients with acute respiratory distress (ARDS)

Acute respiratory distress syndrome (ARDS) is today a leading cause of hospitalization in intensive care unit (ICU). ARDS and pneumonia are closely related to critically ill patients; however, the etiologic agent is not always identified. The presence of human herpes simplex virus 1, human cytomegalovirus and Epstein–Barr virus in respiratory samples of critically ill patients is increasingly reported even without canonical immunosuppression. The main aim of this study was to better understand the significance of herpesviruses finding in lower respiratory tract of ARDS patients hospitalized in ICU. The presence of this group of herpesviruses, in addition to the research of influenza viruses and other common respiratory viruses, was investigated in respiratory samples from 54 patients hospitalized in ICU, without a known microbiological causative agent. Moreover, the immunophenotype of each patient was analyzed. Herpesviruses DNA presence in the lower respiratory tract seemed not attributable to an impaired immunophenotype, whereas a significant correlation was observed between herpesviruses positivity and influenza virus infection. A higher ICU mortality was significantly related to the presence of herpesvirus infection in the lower respiratory tract as well as to impaired immunophenotype, as patients with poor outcome showed severe lymphopenia, affecting in particular T (CD3+) cells, since the first days of ICU hospitalization. In conclusion, these results indicate that herpesviruses lower respiratory tract infection, which occurs more frequently following influenza virus infection, can be a negative prognostic marker. An independent risk factor for ICU patients with ARDS is an impaired immunophenotype.

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.

Broncholaveolar lavage to detect cytomegalovirus infection, latency, and reactivation in immune competent hosts

Roughly 1/3rd of immune competent patients will reactivate latent cytomegalovirus (CMV) during critical illness. There are no standard methods to detect reactivation, and some investigators have postulated that presence of DNA in BAL fluid is indicative of viral replication. To test this hypothesis, we used a murine model that allows inclusion of matched healthy controls which is not possible in human studies. BALB/c mice infected with Smith-murine CMV or PBS (mock) had BAL evaluated 7, 14, or 21 days after acute infections, during latency, or during bacterial sepsis. Plaque assay, PCR, and rtPCR were performed on BALs and concomitantly obtained lung tissue. BAL cellular compositions, including tetramer evaluation of CMV-specific T cells were evaluated by flow cytometry. CMV DNA were detected in BAL at all time-points during acute infection, becoming undetectable in all mice during latency, then were detected again during bacterial sepsis, peaking 3 weeks after onset. mCMV specific T-cells were most numerous in BAL after acute viral infections, decreasing to low levels during latency, then fluctuating during bacterial sepsis. Specifically, mCMV-specific T-cells contracted at sepsis onset, expanding 2-4 weeks post-sepsis, presumably in response to increased viral loads at that time point. Altogether, our results support the use of BAL PCR for the diagnosis of CMV replication in immune competent hosts. Additionally, we demonstrate dynamic changes in CMV-specific T cells that occur in BAL during CMV infection and during sepsis induced viral reactivation. J. Med. Virol. 88:1408-1416, 2016. © 2016 Wiley Periodicals, Inc.

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.

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

OBJECTIVES

Human herpesvirus 6 is associated with a variety of complications in immunocompromised patients, but no studies have systematically and comprehensively assessed the impact of human herpesvirus 6 reactivation, and its interaction with cytomegalovirus, in ICU patients.

DESIGN

We prospectively assessed human herpesvirus 6 and cytomegalovirus viremia by twice-weekly plasma polymerase chain reaction in a longitudinal cohort study of 115 adult, immunocompetent ICU patients. The association of human herpesvirus 6 and cytomegalovirus reactivation with death or continued hospitalization by day 30 (primary endpoint) was assessed by multivariable logistic regression analyses.

SETTING

This study was performed in trauma, medical, surgical, and cardiac ICUs at two separate hospitals of a large tertiary care academic medical center.

PATIENTS

A total of 115 cytomegalovirus seropositive, immunocompetent adults with critical illness were enrolled in this study.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Human herpesvirus 6 viremia occurred in 23% of patients at a median of 10 days. Human herpesvirus 6B was the species detected in eight samples available for testing. Most patients with human herpesvirus 6 reactivation also reactivated cytomegalovirus (70%). Severity of illness was not associated with viral reactivation. Mechanical ventilation, burn ICU, major infection, human herpesvirus 6 reactivation, and cytomegalovirus reactivation were associated with the primary endpoint in unadjusted analyses. In a multivariable model adjusting for mechanical ventilation and ICU type, only coreactivation of human herpesvirus 6 and cytomegalovirus was significantly associated with the primary endpoint (adjusted odds ratio, 7.5; 95% CI, 1.9-29.9; p = 0.005) compared to patients with only human herpesvirus 6, only cytomegalovirus, or no viral reactivation.

CONCLUSIONS

Coreactivation of both human herpesvirus 6 and cytomegalovirus in ICU patients is associated with worse outcome than reactivation of either virus alone. Future studies should define the underlying mechanism(s) and determine whether prevention or treatment of viral reactivation improves clinical outcome.

Sepsis and cytomegalovirus: foes or conspirators?

Cytomegalovirus (CMV) reactivation in non-immune-suppressed critically ill patients is an area of increasing interest. CMV has long been appreciated as a pathogen in immunocompromised hosts. CMV reactivates in approximately one-third of latently infected non-immune-suppressed hosts during critical illness; however, its role as a pathogen in these patients remains unclear. CMV reactivation has been linked to bacterial sepsis and likely results from inflammation, transient immune compromise, and viral epigenetic changes. While CMV may improve immune response to some bacterial infections, other data suggest that CMV induces exaggerated responses to severe infections that may be harmful to latently infected hosts. These results also suggest that previous infection history may explain significant differences seen between human septic responses and murine models of sepsis. While critically ill human hosts clearly have worse outcomes associated with CMV reactivation, determining causality remains an area of investigation, with randomized control trials currently being performed. Here we review the current literature and highlight areas for future investigation.

Resistant pathogens, fungi, and viruses

Although originally described in Staphylococcus aureus, resistance among bacteria has now become a race to determine which classes of bacteria will become more resistant. Availability of antibacterial agents has allowed the development of entirely new diseases caused by nonbacterial pathogens, related largely to fungi that are inherently resistant to antibacterials. This article presents the growing body of knowledge of the herpes family of viruses, and their occurrence and consequences in patients with concomitant surgical disease or critical illness. The focus is on previously immunocompetent patients, as the impact of herpes viruses in immunosuppressed patients has received thorough coverage elsewhere.

Neutrophils with myeloid derived suppressor function deplete arginine and constrain T cell function in septic shock patients

Introduction

Impaired T cell function in sepsis is associated with poor outcome, but the mechanisms are unclear. In cancer, arginase-expressing myeloid derived suppressor cells (MDSCs) deplete arginine, impair T cell receptor CD3 zeta-chain expression and T cell function and are linked to poor clinical outcome, but their role during acute human infectious disease and in particular sepsis remains unknown. Hypoarginemia is prevalent in sepsis. This study aimed to determine whether neutrophils that co-purify with PBMC express arginase, and if arginine depletion constrains T cell CD3 zeta-chain expression and function in human sepsis.

Methods

Using flow cytometry, cell culture, HPLC, arginase activity and mRNA detection, our study examined whether neutrophils, with reduced buoyant density isolated in the Ficoll interface, metabolise L-arginine and suppress T cell proliferation in sepsis. A total of 35 sepsis patients (23 with septic shock) and 12 hospital controls in a tertiary referral hospital in tropical Australia were evaluated.

Results

Only sepsis patients had interphase neutrophils, neutrophils co-purifying with mononuclear cells (≤1.077 specific gravity). The percentage of interphase neutrophils in sepsis was proportional to sepsis severity and correlated with plasma IL-6 concentrations. Ex vivo, sepsis-derived interphase neutrophils expressed arginase, metabolised culture L-arginine and suppressed T cell proliferation and CD3 zeta-chain expression. In vivo, in septic shock there was a longitudinal inverse association between interphase neutrophil number and CD3 zeta-chain expression. Depletion or inhibition of interphase neutrophils in vitro restored zeta-chain expression and T cell function.

Conclusions

For the first time during an acute human infection, interphase neutrophils that express arginase were found to circulate in sepsis, in proportion to disease severity. These neutrophil-MDSCs impair T cell CD3 zeta-chain expression and T cell function via L-arginine metabolism, and likely contribute to the T cell dysfunction seen in sepsis. Modulation of neutrophil-MDSC or their downstream effects warrant consideration as targets for novel adjunctive therapies in sepsis.

Electronic supplementary material

The online version of this article (doi:10.1186/cc14003) contains supplementary material, which is available to authorized users.

Upregulation of the inhibitory receptor ILT4 in monocytes from septic patients

Sepsis-induced immune dysfunction is a complex phenomenon that involves both innate and adaptive responses. Upregulation of the inhibitor receptor named immunoglobulin like transcript 4 (ILT4) is crucial to the tolerogenic function of monocytes. Here, ILT4 expression, endotoxin-induced IL-12 and IL-10 production and CD86 expression were investigated in circulating monocytes from 16 patients with severe sepsis and 16 age and sex matched controls. We found that monocytes from patients with severe sepsis express significantly higher levels of ILT4 than monocytes from controls. Upregulation of ILT4 expression appeared to be induced by soluble factors present in the serum of septic patients and directly correlated with the degree of organ dysfunction. ILT4(+) monocytes from septic patients also displayed an alteration in the cytokine response to endotoxin stimulation characterized by reduced IL-12 production and increased IL-10 production, and a reduced expression of the costimulatory molecule CD86. In conclusion, the increased ILT4 expression and IL-10 production and the decreased CD86 expression and IL-12 production indicate that during sepsis monocytes undergo substantial modulation of the surface and cytokine phenotype. These phenotypic changes may interfere with the antigen presenting cell activity of monocytes, which may contribute to the impairment of adaptive immune responses that takes place during sepsis.

STAT3-mediated IL-17 production by postseptic T cells exacerbates viral immunopathology of the lung

Survivors of severe sepsis exhibit increased morbidity and mortality in response to secondary infections. Although bacterial secondary infections have been widely studied, there remains a paucity of data concerning viral infections after sepsis. In an experimental mouse model of severe sepsis (cecal ligation and puncture [CLP]) followed by respiratory syncytial virus (RSV) infection, exacerbated immunopathology was observed in the lungs of CLP mice compared with RSV-infected sham surgery mice. This virus-associated immunopathology was evidenced by increased mucus production in the lungs of RSV-infected CLP mice and correlated with increased IL-17 production in the lungs. Respiratory syncytial virus-infected CLP mice exhibited increased levels of TH2 cytokines and reduced interferon γ in the lungs and lymph nodes compared with RSV-infected sham mice. In addition, CD4 T cells from CLP mice produced increased IL-17 in vitro irrespective of the presence of exogenous cytokines or blocking antibodies. This increased IL-17 production correlated with increased STAT3 transcription factor binding to the IL-17 promoter in CD4 T cells from CLP mice. Furthermore, in vivo neutralization of IL-17 before RSV infection led to a significant reduction in virus-induced mucus production and TH2 cytokines. Taken together, these data provide evidence that postseptic CD4 T cells are primed toward IL-17 production via increased STAT3-mediated gene transcription, which may contribute to the immunopathology of a secondary viral infection.

Cytomegalovirus and herpes simplex virus effect on the prognosis of mechanically ventilated patients suspected to have ventilator-associated pneumonia

OBJECTIVE

Cytomegalovirus (CMV) and herpes simplex virus (HSV) are common viruses that can affect critically ill patients who are not immunocompromised. The aim of this study was to determine whether the identification of CMV and/or HSV in mechanically ventilated critically ill patients suspected of having pneumonia was associated with an increased mortality.

DESIGN

Prospective epidemiological study.

SETTING

Medical intensive care unit of a tertiary medical center.

PATIENTS

Ninety-three patients with suspected pneumonia.

INTERVENTIONS

Patients with suspected pneumonia had bronchoalveolar lavage and blood samples taken to confirm the diagnosis. Antigenemia was used to detect CMV in the blood. Bronchoalveolar lavage samples were submitted to testing using quantitative real-time Polymerase Chain Reaction.

MEASUREMENTS AND MAIN RESULTS

We identified 22 patients with a CMV infection, 26 patients with an HSV infection and 45 patients without CMV or HSV infection (control group). Mortality at day 60 was higher in patients with a CMV infection than in patients from the control group (55% vs. 20%, P<0.01). Mortality at day 60 was not significantly increased in the group with HSV infection. Duration of ICU stay and ICU mortality were significantly higher in patients with CMV infections when compared to patients from the control group, whereas ventilator free days were significantly lower in patients with CMV infections when compared to patients from the control group.

CONCLUSIONS

In critically ill patients, a CMV infection is associated with an increased mortality. Further interventional studies are needed to evaluate whether treatment could improve the prognosis.

BK viremia in critically ill surgical patients with hemorrhagic or septic shock

Background

Infections with polyomavirus BK virus (BKV) are a common cause of renal dysfunction after renal transplantation and may also be harmful in surgical patients with shock. The aim of the present study was to determine the frequency of BKV viremia in critically ill surgical patients with septic or hemorrhagic shock, and, if viremia is detectable, whether viremia may be associated with renal dysfunction.

Findings

A total of 125 plasma samples from 44 critically ill surgical patients with septic or hemorrhagic shock were tested by real-time polymerase chain reaction (PCR) for BKV DNA during their stay on the intensive care unit (ICU). BKV viremia occurred in four patients, i.e. in three of the septic and in one of the hemorrhagic shock group. There was no association between viremia and renal dysfunction. All positive samples contained a low viral load (< 500 copies/ml).

Conclusions

Since BK viremia was rarely found and with low viral load only in critically ill surgical patients with shock, it is very unlikely that BK viremia results in BK nephropathy later on.

Viral infections in septic shock (VISS-trial)-crosslinks between inflammation and immunosuppression

BACKGROUND

Recent investigations provided evidence that herpes simplex virus (HSV-1) and cytomegalovirus (CMV) are reactivated in critically ill individuals. However, at this time, it remains unclear whether these viral infections are of real pathogenetic relevance or represent innocent bystanders.

MATERIALS AND METHODS

In total, 60 patients with septic shock were enrolled. Blood samples and tracheal secretion were collected at the time of sepsis diagnosis (T0) as well as 7 d (T1), 14 d (T2), 21 d (T3), and 28 d (T4) later. The following virologic diagnostics were performed: (1) Viral load of herpes simplex virus type1 (HSV-1) and cytomegalovirus (CMV) in blood samples as well as tracheal secretion using polymerase chain reaction (PCR). (2) Detection of CMV-antigen (pp65) in blood samples using immunofluorescence microscopy. Furthermore plasma levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were evaluated using ELISA-kits.

RESULTS

Thirty-one patients (51.7%) were found to be positive for HSV-1, whereas in 16 patients (26.7%) CMV could be identified. Patients with a positive PCR for HSV-1 and/or CMV showed a significantly prolonged length of hospital stay and absolute time of respirator-dependant ventilation. Furthermore, survival curves of patients with a high HSV-1-load (>10E8) in tracheal secretion in comparison with those with a lower HSV-1-load (<10E8) revealed a significantly impaired survival.

CONCLUSIONS

Viral superinfections with HSV-1 or CMV can frequently be observed in patients with septic shock, especially in those with increased disease severity and a prolonged need for respirator-dependant ventilation. In patients with a viral superinfection morbidity is increased, whereas differences in mortality seem to be dosage-dependant.

Cytomegalovirus reactivation in critically ill immunocompetent hosts: a decade of progress and remaining challenges

Human cytomegalovirus (HCMV) is an undisputed pathogen in humans with severe immune compromise, which has historically been thought to carry little consequence in immunocompetent hosts. During the past decade, however, accumulating data suggest that significant numbers of immunocompetent humans reactivate HCMV during critical illness, and that these reactivation episodes are associated with worsened outcomes. Because most people are infected with this ubiquitous virus by adulthood, confirming pathogenicity has now become a clinical priority. In this article, we will review the incidence and implications of reactivation, the relevant immune responses and reactivation triggers relevant to the immunocompetent host. We will summarize the progress made during the past ten years, outline the work ongoing in this field, and identify the major gaps remaining in our emerging understanding of this phenomenon.

The role of viruses in nosocomial pneumonia

PURPOSE OF REVIEW

The frequency and impact of viruses among intensive care unit (ICU) nonimmunocompromised patients remains controversial. This review analyzes their place as causal pathogens in ventilator-associated pneumonia, as well as their effects on ICU patients' outcomes.

RECENT FINDINGS

Herpesviruses, namely herpes simplex virus (HSV) and cytomegalovirus (CMV), are the most frequent viruses detected among nonimmunosuppressed ICU patients, as confirmed by recent prospective studies. Patients infected with these viruses show increased morbidity and, especially for CMV, mortality. An increase of bacterial or fungal superinfections was observed in ICU patients with CMV reactivation. A therapeutic trial of acyclovir (HSV antiviral) in ICU patients was negative. Concerning CMV, pathogenicity was suggested by histologic assessment in ICU patients, and recent murine models with a positive effect of prophylaxis with ganciclovir that prevented postseptic CMV reactivation and secondary lung damage.

SUMMARY

Using efficient and rapid virologic diagnostic tests (antigenemia or PCR), the identification of viruses in ICU patients is frequent. Their role in the occurrence of ventilator-acquired pneumonia and their impact on patient outcome depend on the virus. There is sufficient evidence suggesting CMV pathogenicity to conduct an interventional randomized trial using anti-CMV drugs.

Cytomegalovirus reactivation and associated outcome of critically ill patients with severe sepsis

INTRODUCTION

Sepsis has been identified as a risk factor for human cytomegalovirus (CMV) reactivation in critically ill patients. However, the contribution of CMV reactivation on morbidity and mortality is still controversial. Therefore, we analyzed the incidence and impact of CMV reactivation on outcome in patients with severe sepsis.

METHODS

In a prospective longitudinal double-blinded observational study, 97 adult nonimmunosuppressed CMV-seropositive patients with new onset of severe sepsis were included. Leukocytes, plasma and tracheal secretions were examined weekly for CMV-DNA by PCR. Tracheal secretions were additionally tested for HSV (Herpes Simplex Virus)-DNA. The influence of CMV-reactivation on the endpoints was analysed by Cox proportional-hazard regression analysis. Time-dependency was evaluated by landmark analysis.

RESULTS

Six out 97 died and five were discharged from the hospital within 72 hours and were excluded of the analysis. CMV reactivation occurred in 35 of the 86 (40.69%) analysed patients. HSV infection occurred in 23 of the 35 (65.7%) CMV reactivators. In 10 patients CMV-plasma-DNAemia appeared with a DNA-content below 600 copies/ml in four cases and a peak amount of 2,830 copies/ml on average. In patients with and without CMV reactivation mortality rates were similar (37.1% vs. 35.3%, P = 0.861), respectively. However, in the multivariate COX regression analyses CMV reactivation was independently associated with increased length of stay in the ICU (30.0, interquartile range 14 to 48 vs. 12.0, interquartile range 7 to 19 days; HR (hazard ratio) 3.365; 95% CI (confidence interval) 1.233 to 9.183, P = 0.018) and in the hospital (33.0, interquartile range 24 to 62 vs. 16.0, interquartile range 10 to 24 days, HR 3.3, 95% CI 1.78 to 6.25, P < 0.001) as well as prolonged mechanical ventilation (22.0, interquartile range 6 to 36 vs. 7.5, interquartile range 5 to 15.5 days; HR 2.6,CI 95% 1.39 to 4.94; P < 0.001) and impaired pulmonary gas exchange (six days, interquartile range 1 to 17, vs. three, interquartile range 1 to 7, days in reactivators vs. non-reactivators, P = 0.038). HSV reactivation proved not to be a risk factor for these adverse effects.

CONCLUSIONS

These data indicate an independent correlation between CMV reactivation and increased morbidity in the well-defined group of nonimmunosuppressed patients with severe sepsis, but CMV reactivation had no impact on mortality in this group with low CMV-DNA plasma levels. Thus, the potential harms and benefits of antiviral treatment have to be weighed cautiously in patients with severe sepsis or septic shock.

Cytomegalovirus infection in severe burn patients monitoring by real-time polymerase chain reaction: A prospective study

BACKGROUND

Cytomegalovirus (CMV) infection has been shown to occur not rarely in critically ill patients in the past decade. However, little data are available on CMV infection in burn patients whereas their susceptibility to CMV infection has been proved.

METHODS

We prospectively assessed CMV viremia by real-time polymerase chain reaction and clinical outcome in immunocompetent burn patients with total burn surface area greater than 15%.

RESULTS

Twenty-nine patients were enrolled. The rate of CMV infection was of 71% in CMV seropositive burn patients, and of 12.5% in CMV seronegative burn patients. CMV reactivation was associated with a higher IGS 2 score on admission. High grade CMV viremia was associated with longer mechanical ventilation duration, higher infection number, higher transfused red blood cell number, and longer ICU stays. There were no differences on mortality rate between patients with and without CMV reactivation.

CONCLUSION

CMV infection rate is considerable in burn patients with TBSA greater than 15%. This infection seems to be mostly due to reactivation of latently existing virus.

CMV in critically ill patients: pathogen or bystander?

Despite broad variability in study populations, methodologies for CMV detection, and analytic methods used, multiple studies have documented frequent CMV infection in non-immunocompromised adults with critical illness due to a variety of causes. Higher rates of CMV infection in studies of seropositive patients suggest that reactivation of latent infection rather than primary infection is the main mechanism in this setting. Risk factors for CMV reactivation (other than seropositivity) have not been clearly defined and there does not appear to be a consistent association with severity of illness. Furthermore, CMV reactivation in this setting has been associated with important adverse clinical outcomes, including increased duration of mechanical ventilation, longer length of stay and all-cause mortality. There are several biologically plausible mechanisms that could link CMV reactivation with adverse outcomes, including: direct lung injury (CMV pneumonia), amplification of inflammation systemically and within the lung, or predisposition to other nosocomial infections, but clinical data in the ICU setting are limited. Further observational studies are unlikely to significantly advance our understanding of the role of CMV in critically ill patients. Given the significant impact of critical illness, limited current therapeutic options, the availability of generally well-tolerated antiviral options for CMV, and the clinical data supporting a possible pathogenic role for CMV, there is a strong rationale for a randomised controlled trial of CMV prevention as a novel means of improving the outcomes of critically ill patients.

Virological and immunological features of active cytomegalovirus infection in nonimmunosuppressed patients in a surgical and trauma intensive care unit

Cytomegalovirus (CMV) reactivation occurs frequently in critically ill patients. The natural course of CMV infection and the interaction between CMV and the adaptive immune system in this setting remain poorly defined. Fifty-three CMV-seropositive patients in a surgical and trauma intensive care unit were included in this study. The CMV DNA load in tracheal aspirates (TA) and plasma (PL) was monitored by qPCR. CMV-specific T-cell immunity was assessed by intracellular cytokine staining. Plasma TNF-alpha levels were determined by ELISA. CMV reactivation occurred in 39.7% of patients (23% had CMV DNA detected only in TA). The analysis of TA allowed an earlier diagnosis in 28% of patients. Clearance of CMV DNAemia preceded that of CMV DNA in TA in some episodes. Peak CMV DNA levels were significantly higher in TA than in PL (P = 0.02). CMV reactivation developed in the presence of CMV-specific T cells. Termination of CMV reactivation was associated with an expansion of functional CMV-specific T cells. Plasma levels of TNF-alpha did not allow for the prediction of the occurrence of CMV reactivation. CMV-specific T-cell immunity is preserved in most critically ill patients experiencing CMV reactivation. Analysis of respiratory specimens is imperative for an optimal monitoring of CMV reactivation in this setting.