Impact of herpes simplex virus detection in respiratory specimens of patients with suspected viral pneumonia

Causal relationships of infection with Helicobacter pylori and herpesvirus on periodontitis: A Mendelian randomization study

Background

To explore the causal association between Helicobacter pylori (H. pylori) infection, herpesvirus infection and periodontitis (PD) from a genetic perspective using Mendelian randomization (MR).

Methods

The PD data were derived from genome-wide association study (GWAS) from the Dental Endpoints (GLIDE) consortium, and the FinnGen Biobank provided data on H. pylori and herpesvirus infections. In addition, we examined GWAS data for subtypes of H. pylori and herpesvirus infection. Inverse variance weighting (IVW) was selected as a major analysis technique, and weighted median (WM), weighted model, simple model, and MR-Egger regression were added as supplementary methods. To verify the findings, the effects of pleiotropy and heterogeneity were assessed.

Results

Genetically predicted H. pylori infection (OR = 0.914, 95%CI = 0.693-1.205, P = 0.523), anti-H. pylori VacA (OR = 0.973, 95%CI = 0.895-1.057, P = 0.515), anti-H. pylori CagA (OR = 1.072, 95%CI = 0.986-1.164; P = 0.102), Epstein-Barr virus (EBV) infection (OR = 1.026, 95%CI = 0.940-1.120, P = 0.567), Herpes simplex virus (HSV) infection (OR = 0.962, 95%CI = 0.883-1.048, P = 0.372), cytomegalovirus (CMV) infection (OR = 1.025, 95%CI = 0.967-1.088, P = 0.415), EBV nuclear antigen-1 (EBNA1) (OR = 1.061, 95%CI = 0.930-1.209, P = 0.378), EBV virus capsid antigen (VCA) (OR = 1.043, 95CI% = 0.890-1.222, P = 0.603), HSV-1 (OR = 1.251, 95%CI = 0.782-2.001, P = 0.351), HSV-2 (OR = 1.020, 95%CI = 0.950-1.096, P = 0.585), CMV IgG (OR = 0.990, 95CI% = 0.882-1.111, P = 0.861) were not associated with PD, indicated that H. pylori and herpesvirus infection had no causal relationship to PD. Reverse studies also found no cause effect of PD on H. pylori or herpesvirus infection. The results of the sensitivity analysis suggested the robustness of the MR results.

Conclusion

This study offered preliminary proof that H. pylori and herpesvirus infections were not causally linked to PD, and vice versa. However, more robust instrumental variables (IVs) and larger samples of GWAS data were necessary for further MR analysis.

Effect of acyclovir therapy on the outcome of mechanically ventilated patients with lower respiratory tract infection and detection of herpes simplex virus in bronchoalveolar lavage: protocol for a multicentre, randomised controlled trial (HerpMV)

INTRODUCTION

Herpes simplex virus (HSV) is frequently detected in the respiratory tract of mechanically ventilated patients and is associated with a worse outcome. The aim of this study is to determine whether antiviral therapy in HSV-positive patients improves outcome.

METHODS AND ANALYSIS

Prospective, multicentre, open-label, randomised, controlled trial in parallel-group design. Adult, mechanically ventilated patients with pneumonia and HSV type 1 detected in bronchoalveolar lavage (≥105 copies/mL) are eligible for participation and will be randomly allocated (1:1) to receive acyclovir (10 mg/kg body weight every 8 hours) for 10 days (or until discharge from the intensive care unit if earlier) or no intervention (control group). The primary outcome is mortality measured at day 30 after randomisation (primary endpoint) and will be analysed with Cox mixed-effects model. Secondary endpoints include ventilator-free and vasopressor-free days up to day 30. A total of 710 patients will be included in the trial.

ETHICS AND DISSEMINATION

The trial was approved by the responsible ethics committee and by Germany's Federal Institute for Drugs and Medical Devices. The clinical trial application was submitted under the new Clinical Trials Regulation through CTIS (The Clinical Trials Information System). In this process, only one ethics committee, whose name is unknown to the applicant, and Germany's Federal Institute for Drugs and Medical Devices are involved throughout the entire approval process. Results will be published in a journal indexed in MEDLINE and CTIS. With publication, de-identified, individual participant data will be made available to researchers.

TRIAL REGISTRATION NUMBER

NCT06134492.

Herpes Simplex Virus Bronchopneumonitis in Critically Ill Patients with Acute on Chronic Liver Failure: A Retrospective Analysis

(1) Background: Critically ill patients are frequently diagnosed with pulmonary Herpes simplex virus-1 (HSV) reactivation, which then can lead to HSV bronchopneumonitis and is associated with higher mortality and longer mechanical ventilation. For the particular subgroup of critically ill patients with acute on chronic liver failure (ACLF), however, the impact of HSV reactivation is unknown. We investigated the impact of HSV reactivation in these patients. (2) Methods: We conducted a retrospective analysis, evaluating data from 136 mechanically ventilated patients with ACLF between January 2016 and August 2023. Clinical parameters were compared between patients with and without HSV bronchopneumonitis. (3) Results: 10.3% were diagnosed with HSV bronchopneumonitis (HSV group). Mortality did not differ between the HSV and non-HSV group (85.7% vs. 75.4%, p = 0.52). However, the clinical course in the HSV group was more complicated as patients required significantly longer mechanical ventilation (14 vs. 21 days, p = 0.04). Furthermore, fungal superinfections were significantly more frequent in the HSV group (28.6% vs. 6.6%, p = 0.006). (4) Conclusions: Mortality of critically ill patients with ACLF with HSV bronchopneumonitis was not increased in spite of the cirrhosis-associated immune dysfunction. Their clinical course, however, was more complicated with significantly longer mechanical ventilation.

Updates in the management of respiratory virus infections in ICU patients: revisiting the non-SARS-CoV-2 pathogens

INTRODUCTION

Although viruses are an underestimated cause of community-acquired pneumonias (CAP) and hospital-acquired pneumonias (HAP)/ventilator-associated pneumonias (VAP) in intensive care unit (ICU) patients, they have an impact on morbidity and mortality.

AREAS COVERED

In this perspective article, we discuss the available data regarding the management of severe influenza CAP and herpesviridae HAP/VAP. We review diagnostic and therapeutic strategies in order to give clear messages and address unsolved questions.

EXPERT OPINION

Influenza CAP affects yearly thousands of people; however, robust data regarding antiviral treatment in the most critical forms are scarce. While efficacy of oseltamivir has been investigated in randomized controlled trials (RCT) in uncomplicated influenza, only observational data are available in ICU patients. Herpesviridae are an underestimated cause of HAP/VAP in ICU patients. Whilst incidence of herpesviridae identification in samples from lower respiratory tract of ICU patients is relatively high (from 20% to 50%), efforts should be made to differentiate local reactivation from true lung infection. Only few randomized controlled trials evaluated the efficacy of antiviral treatment in herpesviridae reactivation/infection in ICU patients and all were exploratory or negative. Further studies are needed to evaluate the impact of such treatment in specific populations.

Risk factors for <em>Herpes simplex</em> virus (HSV) and <em>Cytomegalovirus</em> (CMV) infections in critically-ill COVID-19 patients

Background

To assess the prevalence of Herpes simplex and Cytomegalovirus infection in respiratory samples of critically-ill COVID-19 patients, its role in outcome and mortality and the influence of dexamethasone treatment in the early stage of SARS-CoV-2 infection.

Methods

All mechanically ventilated COVID-19 patients treated on ICU between March 2020 and January 2021 were included. Respiratory specimens were tested for Herpes simplex virus (HSV) type 1, 2 and Cytomegalovirus (CMV) by quantitative real-time PCR. Clinical parameters were compared in the cohorts with and without HSV-1- infection.

Results

134 patients with a median age of 72.5 years (73.0% male, n=98) were included. HSV-1 reactivation occurred in 61 patients (45.5%), after median 9 (7-13) days of mechanical ventilation. The main factor for reactivation was length of stay on ICU (24 days vs 13 days, p<0.001) and duration of mechanical ventilation (417 vs 214 hours, p<0.001). Treatment with dexamethasone and a history of immunosuppression did not associate with HSV-infection in the univariate analysis (39 vs 41, p=0.462 and 27.9% vs 23.3%, p=0.561, respectively). Both ICU and hospital mortality were not significantly different in the cohorts with and without HSV-infection (57.4% vs 45.2%, p=0.219).

Conclusions

Our study shows a high prevalence of HSV-infection in critically-ill COVID-19 patients which was unexpectedly higher than the prevalence of CMV-infections and unrelated to dexamethasone treatment. The main risk factors for HSV and CMV in the studied cohorts were the length of ICU stay and duration of mechanical ventilation. Therefore, we recommend routine monitoring of critically ill COVID-19 patients for these viral co-infections and consider treatment in those patients.

Herpes Simplex Virus Pneumonia Mimicking Legionella Pneumonia in an Elderly Patient With Heart and Liver Failure

The diagnosis of viral pneumonia is often difficult because of its varied presentations. Regarding the serological diagnosis of viral infections, it is difficult to perform a viral DNA test in general medical facilities, especially in rural settings. Among viral pneumonia cases, herpes simplex virus (HSV) pneumonia can occur in immunocompromised hosts. However, when the clinical course of HSV pneumonia is acute, and the features of pneumonia are not distinct, the diagnosis can be challenging. We report the case of a 69-year-old man who visited the hospital with complaints of dyspnea and cough for two days. Although the patient had no fever and the urine was negative for Legionella antigen, we suspected Legionella pneumonia based on the clinical course, Gram stain of sputum, and CT findings. After undergoing treatment with antibiotics, his condition worsened, with dyspnea and an increase in the demand for oxygen at 5 L. The patient also had complications related to the heart and liver. The sputum culture was negative, and the HSV serum test revealed that HSV IgM level was elevated to 1.16 (reference value: ≤0.80) and IgG level at admission and at follow-up 21 days later was elevated to 28.1 and 60.0 respectively (reference value: ≤2.0); accordingly, the patient was diagnosed with HSV pneumonia. In cases of pneumonia with atypical courses, the coexistence of multiple diseases, and immunosuppression, HSV pneumonia should be included in the differential diagnosis. In rural settings, viral pneumonia should be investigated using antibodies against viruses due to the limited availability of other medical resources. When a patient is judged to be immunosuppressed in the treatment of pneumonia of unknown cause, it is important to consider the possibility of HSV infection and take prompt action. Furthermore, it is essential to consider the possibility of multi-organ failure secondary to HSV infection, which requires systemic management.

Reactivation of Herpes Simplex Virus Type 1 (HSV-1) Detected on Bronchoalveolar Lavage Fluid (BALF) Samples in Critically Ill COVID-19 Patients Undergoing Invasive Mechanical Ventilation: Preliminary Results from Two Italian Centers

Reactivation of herpes simplex virus type 1 (HSV-1) has been described in critically ill patients with coronavirus disease 2019 (COVID-19) pneumonia. In the present two-center retrospective experience, we primarily aimed to assess the cumulative risk of HSV-1 reactivation detected on bronchoalveolar fluid (BALF) samples in invasively ventilated COVID-19 patients with worsening respiratory function. The secondary objectives were the identification of predictors for HSV-1 reactivation and the assessment of its possible prognostic impact. Overall, 41 patients met the study inclusion criteria, and 12/41 patients developed HSV-1 reactivation (29%). No independent predictors of HSV-1 reactivation were identified in the present study. No association was found between HSV-1 reactivation and mortality. Eleven out of 12 patients with HSV-1 reactivation received antiviral therapy with intravenous acyclovir. In conclusion, HSV-1 reactivation is frequently detected in intubated patients with COVID-19. An antiviral treatment in COVID-19 patients with HSV-1 reactivation and worsening respiratory function might be considered.

Outcomes of Herpes Simplex Virus Pneumonitis in Critically Ill Patients

Critically ill patients, such as those in intensive care units (ICUs), can develop herpes simplex virus (HSV) pneumonitis. Given the high prevalence of acute respiratory distress syndrome (ARDS) and multiple pre-existing conditions among ICU patients with HSV pneumonitis, factors predicting mortality in this patient population require further investigation. In this retrospective study, the bronchoalveolar lavage or sputum samples of ICU patients were cultured or subjected to a polymerase chain reaction for HSV detection. Univariable and multivariable Cox regressions were conducted for mortality outcomes. The length of hospital stay was plotted against mortality on Kaplan–Meier curves. Among the 119 patients with HSV pneumonitis (age: 65.8 ± 14.9 years), the mortality rate was 61.34% (73 deaths). The mortality rate was significantly lower among patients with diabetes mellitus (odds ratio [OR] 0.12, 95% confidence interval [CI]: 0.02–0.49, p = 0.0009) and significantly higher among patients with ARDS (OR: 4.18, 95% CI: 1.05–17.97, p < 0.0001) or high (≥30) Acute Physiology and Chronic Health Evaluation II scores (OR: 1.08, 95% CI: 1.00–1.18, p = 0.02). Not having diabetes mellitus (DM), developing ARDS, and having a high Acute Physiology and Chronic Health Evaluation II (APACHE II) score were independent predictors of mortality among ICU patients with HSV pneumonitis.

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.

Efficacy and safety of antiviral therapy in critically ill patients with mechanical ventilation: a meta-analysis with trial sequential analysis of randomized controlled trials

BACKGROUND

Viral reactivation is frequently detected in critically ill patients with mechanical ventilation and is associated with worse outcomes. However, the efficacy and safety of antiviral therapy in these patients remain unknown.

OBJECTIVES

To assess the effects of antiviral therapy on mortality, viral reactivation, and adverse events in critically ill patients with mechanical ventilation.

DATA SOURCES

Medline, Embase, the Cochrane Library, and reference lists.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials that compared antiviral therapy with placebo, standard care, or no treatment.

PARTICIPANTS

Critically ill patients with mechanical ventilation.

INTERVENTIONS

Antiviral therapy.

ASSESSMENT OF RISK OF BIAS

Cochrane risk of bias tool.

METHODS OF DATA SYNTHESIS

Risk ratios (RR) with 95% confidence intervals (CIs) were pooled using a random-effects model for meta-analysis with trial sequential analysis.

RESULTS

Nine trials with a broad spectrum of critically ill patients were included. No association was found between antiviral therapy and all-cause mortality at the longest follow-up (nine trials; 1790 patients; RR 0.93, 95% CI 0.79-1.11; I² = 3%). Trial sequential analysis showed that the cumulative Z-curve crossed the futility boundary establishing sufficient evidence. No association also was found between antiviral therapy and 28-day mortality, in-hospital mortality, 60-day mortality, or 90-day mortality. But antiviral therapy was associated with a reduction in viral reactivation (five trials; 644 patients; RR 0.23, 95% CI 0.14-0.37; I² = 0%). Trial sequential analysis showed that the cumulative Z-curve crossed the trial sequential monitoring boundary for benefit establishing sufficient evidence. Antiviral therapy was not associated with an increased risk of renal insufficiency (eight trials; 1574 patients; RR 0.88, 95% CI 0.73-1.05; I² =0%).

CONCLUSIONS

No association between antiviral therapy and mortality was found, but antiviral therapy reduced viral reactivation without increasing the risk of renal insufficiency in critically ill patients with mechanical ventilation.

High rate of HSV-1 reactivation in invasively ventilated COVID-19 patients: Immunological findings

SARS-CoV-2 infection can lead to severe acute respiratory distress syndrome with the need of invasive ventilation. Pulmonary herpes simplex-1 (HSV-1) reactivation in invasively ventilated patients is a known phenomenon. To date very little is known about the frequency and the predisposing factors of HSV-1 reactivation in COVID-19. Therefore, we evaluated our cohort of invasively ventilated COVID-19 patients with severe pneumonia for HSV-1 in respiratory specimens and combined these results with functional immunomonitoring of the peripheral blood. Tracheal secretions and bronchial lavages were screened by PCR for HSV-1 positivity. Comprehensive immunophenotyping and quantitative gene expression analysis of Interferon-stimulated genes (IFI44L, MX1, RSAD2, ISIG15 and IFIT1) and IL-1 beta were performed in whole blood. Time course of infection beginning at symptom onset was grouped into three phases ("early" phase 1: day 1-10, "middle" phase 2: day 11-30 and "late" phase 3: day 31-40). Pulmonary HSV-1 reactivation was exclusively observed in the later phases 2 and 3 in 15 of 18 analyzed patients. By FACS analysis a significant increase in activated CD8 T cells (CD38+HLADR+) in phase 2 was found when compared with phase 1 (p<0.05). Expression of Interferon-stimulated genes (IFI44L, RSAD2 ISIG15, MX1, IFIT1) was significantly lower after HSV-1 detection than before. Taken together, reactivation of HSV-1 in the later phase of SARS-CoV-2- infection occurs in parallel with a drop of antiviral innate responsiveness as shown by decreased expression of Interferon-stimulated genes and a concurrent increase of highly activated CD38+HLADR+ CD8 T cells.

Characteristics of viral pneumonia in the COVID-19 era: an update

Influenza virus, rhinovirus, and adenovirus frequently cause viral pneumonia, an important cause of morbidity and mortality especially in the extreme ages of life. During the last two decades, three outbreaks of coronavirus-associated pneumonia, namely Severe Acute Respiratory Syndrome, Middle-East Respiratory Syndrome, and the ongoing Coronavirus Infectious Disease—2019 (COVID-19) were reported. The rate of diagnosis of viral pneumonia is increasingly approaching 60% among children identified as having community-acquired pneumonia (CAP). Clinical presentation ranges from mild to severe pneumonitis complicated by respiratory failure in severe cases. The most vulnerable patients, the elderly and those living with cancer, report a relevant mortality rate. No clinical characteristics can be useful to conclusively distinguish the different etiology of viral pneumonia. However, accessory symptoms, such as anosmia or ageusia together with respiratory symptoms suggest COVID-19. An etiologic-based treatment of viral pneumonia is possible in a small percentage of cases only. Neuraminidase inhibitors have been proven to reduce the need for ventilatory support and mortality rate while only a few data support the large-scale use of other antivirals. A low-middle dose of dexamethasone and heparin seems to be effective in COVID-19 patients, but data regarding their possible efficacy in viral pneumonia caused by other viruses are conflicting. In conclusion, viral pneumonia is a relevant cause of CAP, whose interest is increasing due to the current COVID-19 outbreak. To set up a therapeutic approach is difficult because of the low number of active molecules and the conflicting data bearing supportive treatments such as steroids.

Effect of antiviral therapy on the outcomes of mechanically ventilated patients with herpes simplex virus detected in the respiratory tract: a systematic review and meta-analysis

Background

Herpes simplex virus (HSV) is frequently detected in the respiratory tract of mechanically ventilated patients. The aim of this study was to assess current evidence to determine whether antiviral therapy is associated with better outcomes in these patients.

Methods

MEDLINE, ISI Web of Science, Cochrane Database and ClinicalTrials.gov were searched from inception to 25 May 2020. All clinical studies investigating the effects of antiviral therapy on the outcome of mechanically ventilated ICU patients in whom HSV was detected in the respiratory tract were eligible for inclusion, regardless of study design, publication status or language. Titles and abstracts were reviewed independently by two authors. If the articles seemed eligible, full-text articles were reviewed and data extracted.

We performed a random-effects meta-analysis to estimate relative risks (RRs) with corresponding 95% confidence intervals (CIs). The primary endpoint was hospital all-cause mortality.

Results

Nine studies were included in the meta-analysis (one randomized controlled trial, eight cohort studies). Antiviral treatment was associated with lower hospital mortality (with antiviral treatment, 40.6% (189 out of 465 patients); without, 52.7% (193 out of 366 patients); RR 0.74 [0.64, 0.85]; eight studies, low quality of evidence). Furthermore, antiviral treatment was associated with lower 30-day mortality (RR 0.75 [0.59, 0.94]; three studies, very low quality of evidence). We did not observe evidence for differences in ICU mortality (RR 0.73 [0.51, 1.05]; three studies, very low quality of evidence).

Conclusions

This meta-analysis of the available data shows that antiviral therapy might result in lower hospital and 30-day all-cause mortality in mechanically ventilated ICU patients who are positive for HSV in the respiratory tract. However, this result must be interpreted with great caution due to the high risk of bias and limited number of patients. Large, well-designed randomized controlled clinical trials are urgently needed.

Trial registration

The study was registered in advance on International Prospective Register of Systematic Reviews (CRD42020180053).

Effect of Antiviral Therapy on the Outcome of Mechanically Ventilated Patients With Herpes Simplex Virus Type 1 in BAL Fluid: A Retrospective Cohort Study

BACKGROUND

Herpes simplex virus type 1 (HSV-1) is frequently detected in the BAL fluid of patients on mechanical ventilation.

RESEARCH QUESTION

The aim of the study was to investigate whether antiviral therapy is associated with improved overall survival within 30 days.

STUDY DESIGN AND METHODS

This was a retrospective cohort study in four ICUs between January 2011 and December 2017. All adult patients on mechanical ventilation with a respiratory tract infection with positive polymerase chain reaction testing for HSV-1 in the BAL were included. Patients already receiving antiviral agents on the day BAL was performed were excluded. We performed uni- and multivariable Cox and logistic regression modeling.

RESULTS

Overall, 306 patients were included in the analysis. Among them, 177 patients (57.8%) received antiviral therapy (90.9% acyclovir, 6.2% ganciclovir, 2.9% both). The overall 30-day mortality rate was 42.4% (n = 75) in the antiviral treatment group and 50.4% (n = 65) in the control group. The adjusted hazard ratio (HR) for the primary outcome was 0.62 (95% CI, 0.44-0.87; P = .005), indicating better overall survival within 30 days for the antiviral-treated group than for the untreated group. This benefit was also present in the subgroup of patients without immunosuppression (n = 246; adjusted HR, 0.53; 95% CI, 0.36-0.78; P = .001). Overall, the median lengths of hospital stay (31 vs 24 days, P = .002) and ICU stay (24 vs 17 days, P < .001), and the duration of mechanical ventilation (18 vs 11 days, P < .001), were longer for patients with therapy. No evidence for the treatment-related deterioration of renal function was observed.

INTERPRETATION

These data suggest that detection of HSV-1 in the BAL of patients on mechanical ventilation may be of clinical significance and that specific antiviral treatment may improve clinical outcomes. However, this needs to be proven in multicenter randomized controlled trials before implementation into the clinical routine.

Impact of acyclovir use on survival of patients with ventilator-associated pneumonia and high load herpes simplex virus replication

Background

Herpes simplex virus (HSV) replication can be detected in the respiratory secretions of a high proportion of ventilated intensive care unit (ICU) patients. However, the clinical significance remains poorly defined. We investigated whether patients with ventilator-associated pneumonia not responding to antibiotics and in whom high levels of HSV could be detected in respiratory secretions benefit from acyclovir treatment.

Methods

Respiratory secretions (bronchoalveolar lavage fluid or tracheal aspirates) were tested for HSV replication by quantitative real-time PCR. ICU survival times, clinical parameters, and radiographic findings were retrospectively compared between untreated and acyclovir treated patients with high (> 10⁵ HSV copies/mL) and low (10³–10⁵ HSV copies/mL) viral load.

Results

Fifty-seven low and 69 high viral load patients were identified. Fewer patients with high viral load responded to antibiotic treatment (12% compared to 40% of low load patients, p = 0.001). Acyclovir improved median ICU survival (8 vs 22 days, p = 0.014) and was associated with a significantly reduced hazard ratio for ICU death (HR = 0.31, 95% CI 0.11–0.92, p = 0.035) in high load patients only. Moreover, circulatory and pulmonary oxygenation function of high load patients improved significantly over the course of acyclovir treatment: mean norepinephrine doses decreased from 0.05 to 0.02 μg/kg body weight/min between days 0 and 6 of treatment (p = 0.049), and median PaO₂/FiO₂ ratio increased from 187 to 241 between day 3 and day 7 of treatment (p = 0.02). Chest radiographic findings also improved significantly (p < 0.001).

Conclusions

In patients with ventilator-associated pneumonia, antibiotic treatment failure, and high levels of HSV replication, acyclovir treatment was associated with a significantly longer time to death in the ICU and improved circulatory and pulmonary function. This suggests a causative role for HSV in this highly selected group of patients.

Severe herpes simplex virus pneumonia in an elderly, immunocompetent patient

Although not common, herpes simplex virus (HSV) pneumonia can occur in immunocompromised patients. However, HSV pneumonia in immunocompetent hosts is very rare. The authors encountered a very rare case of severe HSV pneumonia in an immunocompetent host. The patient was an 85-year-old Japanese woman who presented with severe intractable pneumonia refractory to empirical antimicrobial therapy. Furthermore, the causative microorganisms remained unknown. Therefore, cytological examination of bronchoalveolar lavage fluid and protected brush biopsy of the lower respiratory tract were performed, which indicated herpes virus-infected cells with nuclear inclusions; PCR assay was positive for HSV DNA. Accordingly, the patient was diagnosed with HSV pneumonia. Her respiratory condition improved immediately after initiation of acyclovir monotherapy. In selected cases of intractable pneumonia refractory to standard antimicrobial therapy, the possibility of HSV pneumonia should be pursued.

Reactivation of herpes simplex type 1 in pneumococcal meningitis

BACKGROUND

Acute bacterial meningitis (ABM) and herpes simplex type 1 (HSV-1) encephalitis are two rare but serious infections affecting the central nervous system (CNS). Concurrent bacterial and viral CNS infection has occasionally been reported.

OBJECTIVES

To illustrate the possibility of intrathecal infection with both Streptococcus pneumonia and HSV-1 by presenting a case and to examine whether herpesvirus reactivation is common in ABM.

STUDY DESIGN

We report a case diagnosed with HSV-1 reactivation in the cerebrospinal fluid (CSF) during treatment for pneumococcal ABM. A retrospective analysis of CSF samples from 21 patients with ABM was performed, with analysis of DNA from HSV-1 and four other neurotropic herpesviruses.

RESULTS

All 21CSF samples were negative for HSV-1, HSV-2, varicella zoster-virus, Epstein-Barr virus and human herpesvirus 6 DNA by PCR.

CONCLUSIONS

Although herpesvirus infection does not seem to be a common phenomenon in ABM we suggest that HSV-1 reactivation could be kept in mind if patients with ABM show symptoms or signs compatible with encephalitis.

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.

What role do viruses play in nosocomial pneumonia?

PURPOSE OF THE REVIEW

Viruses are an increasingly recognized cause of community-acquired pneumonia (CAP), but their exact role in nosocomial pneumonia is still debated. This review focuses on the role of viruses as a cause of nosocomial pneumonia.

RECENT FINDINGS

Respiratory viruses may be responsible for healthcare-associated pneumonia, because affected patients and those with CAP have the same risk factors for viral disease. In mechanically ventilated patients, viruses belonging to the Herpesviridae family, namely herpes simplex virus (HSV) and cytomegalovirus, can be reactivated and cause bronchopneumonitis or ventilator-associated pneumonia, respectively. Recent results confirmed the high rate of HSV reactivation in the distal airways of mechanically ventilated patients, and that patients with high virus loads (>10(5)  copies/ml of bronchoalveolar lavage fluid) have poorer outcomes than those with low or no virus load. However, the responsibility of mimivirus, initially described as a possible cause of pneumonia, was not confirmed for nosocomial pneumonia.

SUMMARY

Respiratory viruses are mainly responsible for CAP, but they may also cause healthcare-associated pneumonia. HSV bronchopneumonitis and cytomegalovirus pneumonia are not rare diseases, and patients with Herpesviridae lung infections have worse prognoses than those without. Whether or not those Herpesviridae infections are responsible for true morbidity or morbidity remains to be determined.

Is acyclovir effective among critically ill patients with herpes simplex in the respiratory tract?

BACKGROUND AND OBJECTIVE

The relevance of the detection of herpes simplex virus type 1 (HSV-1) in the respiratory tract of patients in the intensive care unit (ICU) is unclear. Therefore, it is uncertain whether treatment with an antiviral agent could be beneficial for these patients.

STUDY DESIGN

We retrospectively reviewed the records of ICU patients with a positive HSV-1 culture in the respiratory tract or bronchoalveolar lavage (BAL) fluid. We evaluated whether acyclovir treatment (n=106) could have a beneficial effect on mortality as compared with the standard treatment (n=106).

RESULTS

Acyclovir treatment was positively linked to in-hospital and ICU-mortality reduction. This favourable influence remained present after correcting for possible confounders and using propensity-adjusted and propensity-matched cohorts: with an odds ratio in the treated group of 3.19 (95% CI 1.79-5.69, p=0.001) for ICU survival and of 3.55 (95% CI 2.16-5.85, p<0.001) for in-hospital survival. The subgroup with HSV-1 detected in the BAL-fluid is the sole contributor to this difference. In the BAL-fluid detected group, 48% (n=10) of non-treated patients died in the ICU, versus 21% (n=6) in the acyclovir-treated group (p=0.033), occurring despite an even longer duration of ventilation or ICU stay.

CONCLUSIONS

These data highlight the hypothesis that it might be worthwhile to consider treatment of HSV-1 in ICU patients depending on the type of respiratory sample in which the virus is detected. These results warrant a prospective trial to prove causality.

Detection of herpes viruses by multiplex and real-time polymerase chain reaction in bronchoalveolar lavage fluid of patients with acute lung injury or acute respiratory distress syndrome

BACKGROUND

Human herpes viruses (HHVs) are important pathogens in acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Rapid and efficient diagnostic tools are needed to detect HHVs in the lung in ALI/ARDS patients.

OBJECTIVES

This study aimed to evaluate the usefulness of multiplex and real-time polymerase chain reaction (PCR) analysis of bronchoalveolar lavage fluid (BALF) for detecting HHV reactivation in ALI/ARDS patients.

METHODS

Between August 2008 and July 2012, eighty-seven BALF samples were obtained from ALI/ARDS patients with unknown etiology and analyzed for HHVs. The types of HHVs in the BALF samples were determined using qualitative multiplex PCR followed by quantitative real-time PCR.

RESULTS

Multiplex PCR identified herpes simplex virus type 1 (HSV-1) (n = 11), Epstein-Barr virus (EBV) (n = 16), cytomegalovirus (CMV) (n = 21), HHV type 6 (HHV-6) (n = 2), and HHV-7 (n = 1) genomic DNA in 35 (40%) of the BALF samples, including 14 (16%) samples containing 2 or 3 HHV types. CMV and EBV reactivation was rare in immunocompetent patients, whereas reactivation of HSV-1 was predominantly observed in intubated patients regardless of their immune status. Overall, HHVs were almost exclusively found in patients with immunosuppression or endotracheal intubation. Real-time PCR detected 0.95-1.59 × 10(6) copies of viral DNA/μg human genome DNA, and HSV-1 (n = 4), CMV (n = 9), and HHV-6 (n = 1) were identified as potentially pathogenic agents.

CONCLUSIONS

The implementation of multiplex and real-time PCR of BALF was feasible in ALI/ARDS patients, which allowed efficient detection and quantification of HHV DNA.

Clinical correlates of herpes simplex virus type 1 loads in the lower respiratory tract of critically ill patients

BACKGROUND

The significance of isolation of herpes simplex virus (HSV) type 1 from the lower respiratory tract in critically ill patients on mechanical ventilation is still unclear. In the current study, we used polymerase chain reaction techniques to quantify HSV-1 to further evaluate its role.

OBJECTIVES

The hypothesis was that high loads reflect invasive pulmonary disease related to prolonged mechanical ventilation and increased mortality, as opposed to shedding from the upper respiratory tract, which leads to lower viral loads.

STUDY DESIGN

We prospectively studied 77 consecutive patients admitted to the intensive care unit and analyzed 136 tracheal aspirates or bronchoalveolar lavage fluids, taken when clinically indicated in the diagnostic workup of fever, radiologic pulmonary infiltrates, progressive respiratory insufficiency or combinations. Samples were cultured for bacteria and yeasts according to routine microbiological methods and HSV-1 loads were determined by real time quantitative PCR. Viral loads were expressed per number of cells recovered.

RESULTS

HSV-1 load was directly related to the simplified acute physiology score II (rs=0.47, P=0.04) when the first specimen taken proved positive for HSV-1. HSV-1 positivity concurred with Candida spp. colonization. Patients with and without a HSV-1 load did not differ with respect to pulmonary and systemic courses and vital outcomes.

CONCLUSIONS

The data suggest that HSV-1 in the lower respiratory tract originates from shedding in the upper respiratory tract in about 30% of critically ill patients, following immune suppression and reactivation, without invasively infecting the lung. No attributable mortality was observed.

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.

Failure to detect an association between aggressive periodontitis and the prevalence of herpesviruses

BACKGROUND

Herpes simplex virus type 1 (HSV-1), human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) have been suspected to play a causal role in periodontitis pathogenesis. The aim of this study was to determine the prevalence of these viruses in subgingival plaque samples of Caucasian patients with generalized aggressive periodontitis compared to periodontally healthy controls.

METHODS

A total of 65 patients with aggressive periodontitis and 65 unmatched controls from Germany were investigated in the study. Subgingival plaque samples were analysed for the presence of HSV-1, EBV and HCMV by quantitative real-time polymerase chain reaction assays. Viral antibody titres were determined quantitatively by immunosorbent assays.

RESULTS

DNA of HSV-1 and HCMV were detected in 1.5% of the patients and controls, whereas EBV DNA was present in 10.8% and 13.9% respectively. Detection rates of serum IgG against HSV-1 (76.1% versus 73.9%), EBV (98.5% versus 96.9%), HCMV (47.7% versus 46.2%) and IgM levels against HSV-1 (6.2% versus 1.5%), EBV (0% versus 0%), HCMV (0% versus 1.5%) did not significantly differ between patients and controls.

CONCLUSION

The data of our study do not suggest any contribution of HSV-1, EBV or HCMV to aggressive periodontitis in a German population. Ethnic and methodological aspects might have caused conflicting results of previous studies.

Diagnostic workup for diffuse parenchymal lung disease: schematic flowchart, literature review, and pitfalls

PURPOSE

The term diffuse parenchymal lung disease (DPLD) refers to a group of disorders affecting the lung parenchyma that can be categorized into those of known and those of unknown etiology. Early diagnosis is important since some forms of DPLD are characterized by a rapid progression to respiratory failure. Notwithstanding the fact that recently guidelines have been published, some issues concerning the practical evaluation of a patient with suspected DPLD remain unclear.

METHODS

In this article we propose a practical approach to the diagnosis and differentiation of DPLD. Moreover, a critical appraisal is provided based on the current literature and frequent pitfalls are highlighted.

CONCLUSION

we propose a practical workup, but in spite of increasing evidence concerning the diagnosis of DPLD, further studies will be needed to clarify several issues for efficient investigation of newly diagnosed patients with DPLD.

Fatal multiorgan failure associated with disseminated herpes simplex virus-1 infection: a case report

Herpes simplex virus type 1 (HSV-1) infections cause typical dermal and mucosal lesions in children and adults. Also complications to the peripheral and central nervous system, pneumonia or hepatitis are well known. However, dissemination to viscera in adults is rare and predominantly observed in immunocompromised patients. Here we describe the case of a 70-year-old male admitted with macrohematuria and signs of acute infection and finally deceasing in a septic shock with multi organ failure 17 days after admission to intensive care unit. No bacterial or fungal infection could be detected during his stay, but only two days before death the patient showed signs of rectal, orolabial and genital herpes infection. The presence of HSV-1 was detected in swabs taken from the lesions, oropharyngeal fluid as well as in plasma. Post-mortem polymerase chain reaction analyses confirmed a disseminated infection with HSV-1 involving various organs and tissues but excluding the central nervous system. Autopsy revealed a predominantly retroperitoneal diffuse large B-cell lymphoma as the suspected origin of immunosuppression underlying herpes simplex dissemination.

Clinical impact of HSV-1 detection in the lower respiratory tract from hospitalized adult patients

The occurrence and clinical impact of herpes simplex virus (HSV) were evaluated in 342 bronchoalveolar lavage specimens from 237 patients. HSV-1 and HSV-2 were detected in 32.1% and <1% of patients, respectively. A significant difference of HSV-1 prevalence and load was found in relation to admission to intensive care unit, mechanical ventilation and mortality within 28 days; in particular, a viral load ≥10(5) copies/mL bronchoalveolar lavage fluid was significantly associated with critical features. No association was found with immune status or other characteristics. Nine of 21 (42.9%) cases of ventilator-associated pneumonia were positive for HSV-1, with poor outcome in six.

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.

Extracorporeal membrane oxygenation for refractory, life-threatening, and herpes simplex virus 1-induced acute respiratory distress syndrome. Our experience and literature review

We report our first experience of treating an immunocompetent adult patient with acute respiratory distress syndrome (ARDS) due to type 1 herpes simplex (HSV1) pneumonitis, using extracorporeal membrane oxygenation (ECMO). Similar cases reported in literature are reviewed as well. The therapeutic options for this particular complication are discussed. Pneumonia caused by HSV1 is a rare finding in immunocompetent individuals; it occurs more often in immunosuppressed and ventilated patients. It is a severe illness; therefore, early diagnosis and initiation of treatment are imperative. Diagnosis is based on cytologic and histologic findings, viral cultures, or serologic methods. This condition can be reversible; however, often, it can progress into refractory ARDS with limited therapeutic options available. We demonstrate the causative role of HSV1 in refractory ARDS of a previously healthy 18-year-old man who presented to the intensive care unit with acute respiratory distress after a week of flulike syndrome. Due to severe hypoxemia and hypercarbia, the patient required mechanical ventilation and later emergent blood oxygenation with extracorporeal support. For the first time in this condition, we used venovenous ECMO management, to rest the lung, sustain blood oxygenation and end-organ oxygen delivery, and promote potential lung recovery. During ECMO and after our etiologic diagnosis, specific therapy was introduced. After viral negativization, corticosteroid therapy (Meduri protocol) was initiated. Extracorporeal membrane oxygenation allowed us to initiate therapy while maintaining end-organ oxygenation and support the patient until lung recovery. After 18 days of ECMO, our patient recovered completely. Near-normal lung structures and functions were documented on a chest x-ray/computed tomography, thoracic ultrasonography, and pulmonary functional tests at hospital discharge and at a 1-year follow-up. Data suggest that severe pulmonary involvement in HVS1 infection associated with septicemia/shock is a rare but often fatal in immunocompetent adult as well. We suggest that ECMO might be the selected treatment for severe refractory ARDS in this clinical scenario. It seems to be an effective and useful ultimate therapeutic strategy for preventing death and furthermore permitting near-full pulmonary function recovery.

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.