Transmission of herpes simplex virus type 1 infection in an intensive care unit

Nosocomial Infection Caused by Antibiotic-Resistant Organisms in the Intensive-Care Unit

Resistance to antimicrobial agents is an evolving process, driven by the selective pressure of heavy antibiotic use in individuals living in close proximity to others. The intensive care unit (ICU), crowded with debilitated patients who are receiving broad-spectrum antibiotics and being cared for by busy physicians, nurses, and technicians, serves as an ideal environment for the emergence of antibiotic resistance. Problem pathogens presently include multiply resistant gram-negative bacilli, methicillin-resistantStaphylococcus aureus, and the recently emerged vancomycin-resistant enterococci. The prevention of antimicrobial resistance in ICUs should focus on recognition via routine unit-based sur veillance, improved compliance with handwashing and barrier precautions, and antibiotic-use policies tailored to individual units within hospitals.

Primary Maternal Herpes Simplex Virus-1 Gingivostomatitis During Pregnancy and Neonatal Herpes: Case Series and Literature Review

BACKGROUND

Neonatal herpes simplex virus (HSV) is a serious, life-threatening infection that is usually acquired during birth from contact with infected maternal genital secretions. Primary maternal HSV gingivostomatitis is a rare occurrence during pregnancy, and HSV type 1 (HSV-1) neonatal disease after primary maternal HSV gingivostomatitis during pregnancy has not been reported in detail.

METHODS

We reviewed the medical records of neonates (≤28 days of age) with a confirmed diagnosis of neonatal HSV-1 at a single pediatric center from January 1981 to January 2010 to identify cases in which the mother had primary gingivostomatitis during pregnancy or at term.

RESULTS

Seven neonates whose mothers had primary HSV-1 gingivostomatitis during pregnancy were identified from a review of 48 neonates with laboratory-proven HSV-1 neonatal disease. Of the 7 women, 2 presented with symptoms of primary HSV-1 gingivostomatitis during the first trimester and 5 in the third trimester. Three of the neonates developed skin, eye, and mucous membrane disease, 2 developed central nervous system disease, and 2 developed disseminated disease. One of the neonates with disseminated HSV-1 disease died.

CONCLUSIONS

Primary maternal HSV gingivostomatitis during pregnancy may lead to HSV-1 transmission to the neonate. Physicians caring for pregnant women should communicate the diagnosis of HSV gingivostomatitis to the neonate's primary provider to ensure proper surveillance, early evaluation, and prompt treatment.

Clinical relevance of and risk factors for HSV-related tracheobronchitis or pneumonia: results of an outbreak investigation

Introduction

Herpes simplex virus (HSV) type 1 was identified in respiratory specimens from a cluster of eight patients on a surgical intensive care unit within 8 weeks. Six of these patients suffered from HSV-related tracheobronchitis and one from HSV-related pneumonia only. Our outbreak investigation aimed to determine the clinical relevance of and risk factors associated with HSV-related tracheobronchitis or pneumonia in critically ill patients, and to investigate whether the cluster was caused by nosocomial transmission.

Methods

A retrospective cohort study was performed to identify risk factors for the outcomes of HSV-related tracheobronchitis or pneumonia and death using univariable analysis as well as logistic regression analysis. Viruses were typed by molecular analysis of a fragment of the HSV type 1 glycoprotein G.

Results

The cohort of patients covering the outbreak period comprised 53 patients, including six patients with HSV-related tracheobronchitis and one patient with pneumonia only. HSV-related tracheobronchitis or pneumonia was associated with increased mortality (100% in patients with versus 17.8% in patients without HSV-related tracheobronchitis or pneumonia; P < 0.0001). The interaction of longer duration of ventilation and tracheotomy was associated with HSV-related tracheobronchitis or pneumonia in multivariable analysis.

Identical HSV type 1 glycoprotein G sequences were found in three patients and in two patients. The group of three identical viral sequences belonged to a widely circulating strain. The two identical viral sequences were recovered from bronchoalveolar lavages of one patient with HSV-related tracheobronchitis and of one patient without clinical symptoms. These viral sequences showed unique polymorphisms, indicating probable nosocomial transmission.

Conclusion

HSV-related tracheobronchitis or pneumonia is associated with increased mortality in critically ill patients. Care should be taken to avoid nosocomial transmission and early diagnosis should be attempted.

Herpes simplex virus (HSV) pneumonia in a heart transplant: Diagnosis and therapy

Organ transplants are frequently complicated by viral infections. The period of maximum immunosuppression, 1 to 6 months posttransplantation, predisposes one to intracellular pathogens. The most common intracellular viral pathogens in transplant recipients include cytomegalovirus (CMV), herpes simplex virus (HSV), and respiratory syncytial virus (RSV). Cytomegalovirus and HSV are common viral pathogens in the early transplant period (0-1 month posttransplant). Although respiratory syncytial virus commonly presents in the late posttransplant period (> or =6 months posttransplant), HSV pneumonia may be acquired in organ transplants by endogenous reactivation caused by immunosuppression or may be introduced from colonized oropharyngeal secretions into the lower respiratory tract during intubation in patients on ventilators. In ventilated patients without severe preexisting lung disease, HSV pneumonia presents with otherwise unexplained profound/prolonged hypoxemia or "failure to wean." As other viral pneumonias, HSV pneumonia is characterized by profound hypoxemia requiring a high FIo(2), and a highly increased A-a gradient (> or =30). These findings are indicative of an oxygen diffusion defect typical of noninfectious (eg, sarcoidosis) or infectious disorders (eg, HSV, cytomegalovirus, respiratory syncytial virus, Pneumocystis (carinii) jiroveci pneumonia) primarily affecting the interstitium of the lung. We present a case of HSV pneumonia in a heart transplant recipient and include a review of the clinical presentation, diagnostic findings, and therapy of HSV pneumonia.

Tracheobronchitis in the Intensive Care Unit

Tracheobronchitis can be broadly defined as inflammation of the airways between the larynx and the bronchioles. Clinically, this syndrome is recognized by an increase in the volume and purulence of the lower respiratory tract secretions and is frequently associated with signs of variable airflow obstruction. In the intensive care unit (ICU), tracheobronchitis is a relatively common problem with an incidence as high as 10.6% [1]. Although tracheobronchitis is associated with a significantly longer length of ICU stay and a prolonged need for mechanical ventilation, it has not been shown to increase mortality. These outcomes can be improved through the use of antimicrobial agents [1].

Herpes simplex virus type 1 and respiratory disease in critically-ill patients: real pathogen or innocent bystander?

Herpes simplex virus type 1 (HSV-1) has been associated with pulmonary disease, mostly in severely immunocompromised patients. After reactivation and shedding in the oropharynx, the virus may reach the lower respiratory tract by aspiration or by contiguous spread. HSV-1 can be detected in clinical specimens by virus culture or quantitatively by nucleic acid amplification techniques. With these techniques, HSV-1 is often detected in the respiratory secretions of critically-ill patients. However, a clear diagnosis of HSV-1 pneumonia is difficult to establish because clinical criteria, radiological features and laboratory findings all lack specificity. Lower respiratory tract HSV-1 infections have not been associated with specific risk-factors. There is also an absence of consistent data concerning the effect of antiviral treatment on the outcome of critically-ill patients. Further studies are needed to better define the pathogenic role of HSV-1 in the lower respiratory tract of these patients, to improve the diagnosis, and, especially, to assess the need for antiviral treatment in the individual patient.

Infection risks following accidental exposure to blood or body fluids in health care workers: a review of pathogens transmitted in published cases

Hospital staff and all other human or veterinary health care workers, including laboratory, research, emergency service, or cleaning personnel are exposed to the risk of occupational infection following accidental exposure to blood or body fluids (BBF) contaminated with a virus, a bacteria, a parasite, or a yeast. The human immunodeficiency virus (HIV) or those of hepatitis B (HBV) or C (HCV) account for most of this risk in France and worldwide. Many other pathogens, however, have been responsible for occupational infections in health care workers following exposure to BBF, some with unfavorable prognosis. In developed countries, a growing number of workers are referred to clinicians responsible for the evaluation of occupational infection risks following accidental exposure. Although their principal task remains the evaluation of the risks of HIV, HBV, or HCV transmission and the possible usefulness of postexposure prophylaxis, these experts are also responsible for evaluating risks of occupational infection with other emergent or more rare pathogens and their possible timely prevention. The determinants of the risks of infection and the characteristics of described cases are discussed in this article.

Herpes simplex virus 1 pneumonia: patterns on CT scans and conventional chest radiographs

PURPOSE

The goal of our study was to describe the herpes simplex virus type 1 (HSV 1) pneumonia patterns on CT scans and chest radiographs.

METHOD

We retrospectively reviewed clinical records and chest radiographs of 24 patients with HSV 1 pneumonia and 10 with pneumonia from combined HSV and mixed flora infection. We also reviewed CT scans available for eight patients with HSV pneumonia and four with mixed pneumonia.

RESULTS

CT scans of eight patients with HSV pneumonia demonstrated multifocal segmental and subsegmental ground-glass opacities (n = 8), additional focal areas of consolidation (n = 6), scattered distribution (n = 6), and pleural effusions (n = 7). Chest radiographs (23 patients) showed patchy segmental and subsegmental ground-glass opacities and consolidation (n = 23), scattered distribution (n = 20), and pleural effusions (n = 12). Radiographic patterns for isolated HSV pneumonia and mixed flora pneumonia were not significantly different.

CONCLUSION

With a growing population of at-risk immunosuppressed patients, it is important to recognize CT and chest radiography patterns consistent with, although nonspecific for, HSV 1 pneumonia.

Herpes Simplex Infections in the Critical Care Setting

Infections caused by herpes simplex virus (HSV) types 1 and 2 are widely prevalent and usually asymptomatic. In the immunocompromised or severely ill patient, however, HSV can cause a variety of mucosal and systemic syndromes. Organ systems most susceptible include the gastrointestinal tract, lungs, and the central nervous system. Systemic disseminated disease may also occur. With the exception of herpes encephalitis, clinical diagnosis of serious HSV infections is difficult, because it occurs in hosts who are susceptible to a wide range of infectious and metabolic problems. We review the presenting syndromes of HSV infection in the critically ill patient, and outline current concepts for diagnosis and treatment.

Assessing viral retention and elimination in rotary dental instruments

The authors of this article used a laboratory model of herpes simplex virus infection to assess the potential for contamination of dental handpieces by a human viral pathogen. They found that although all the handpieces in the study were fitted with anti-retraction valves, it was not until the units were flushed internally and disinfected externally that the pathogens were eliminated.

Rotary dental instruments and the potential risk of transmission of infection: herpes simplex virus

A laboratory model of herpes simplex virus infection was used to assess the potential contamination of dental handpieces. When contaminated instruments were treated with surface disinfection and internal chemical disinfection, viable virus was eliminated in all instruments.

Restriction enzyme fragment length polymorphisms of amplified herpes simplex virus type-1 DNA provide epidemiologic information

Human herpes simplex type 1 (HSV-1) DNA of isolates from patients in a large teaching hospital was amplified by the polymerase chain reaction (PCR). The PCR products targeted approximately 2100 nt regions of relatively low G + C content. Comparison of restriction enzyme digests of amplified DNA showed variation useful for strain differentiation. Twelve nonrelated HSV-1 were differentiated from one another. In contrast, specimens epidemiologically related in an outbreak were indistinguishable from each other. Restriction endonuclease analysis of amplified HSV-1 sequences appears to be useful for molecular epidemiology and laboratory quality control to detect possible contamination by PCR products.