Predictors of morbidity and mortality in neonates with herpes simplex virus infections. The National Institute of Allergy and Infectious Diseases Collaborative Antiviral Study Group

Acceptance of a rapid herpes test in labour: survey of attitudes of patients and health care providers

OBJECTIVE

To determine the acceptability to pregnant women and their health care providers of a rapid test for genital herpes simplex virus (HSV) in labour.

METHODS

A cross-sectional survey was conducted with outpatient pregnant women and their health care providers (obstetricians, family physicians and midwives) at BC Women's Hospital and Health Centre.

RESULTS

Of pregnant women approached, 207 (92%) completed the survey; 90% reported no history of genital herpes. Rapid HSV testing in labour was acceptable to 85% of pregnant women. Among the 133 women who were planning a vaginal delivery, 63% were willing to consider delivery by Caesarean section and 53% were willing to consider intrapartum anti-viral medications if HSV was present in the genital tract. Of 51 health care providers surveyed, 98% indicated interest in knowing if their patient had a newly acquired HSV infection, while 84% indicated interest in knowing if the patient had a reactivation of infection. If HSV was detected in their patient's genital tract, 36% indicated they would recommend a Caesarean section, and 25% would consider antiviral medication as an investigational intrapartum treatment. Interestingly, both of these proportions increased if the patient had ruptured membranes for more than four hours.

CONCLUSION

Most pregnant women and their health care providers are receptive to the use of a rapid polymerase chain reaction test to detect genital HSV shedding in labour. This supports the development of HSV rapid testing and antiviral therapy trials in the labour setting.

A systematic review of the incidence of sensorineural hearing loss in neonates exposed to Herpes simplex virus (HSV)

OBJECTIVE

To develop evidence-based guidelines for appropriate audiological monitoring of children born following exposure to or infection with Herpes simplex virus (HSV) for development of immediate or delayed-onset of sensorineural hearing loss (SNHL).

DATA SOURCES

A Medline search of the 1966-July 2007 database was supplemented by search of the additional database Embase (1980-July 2007). Manual search was conducted of references of identified papers and book chapters.

STUDY SELECTION

Articles were sought that were longitudinal in design, to include an inception cohort of children infected with (or exposed to) HSV who were entered at a similar point at birth and followed over time with serial audiometry to identify hearing loss if it developed.

DATA EXTRACTION

Patient information and audiometric data extraction from relevant articles was performed independently by all three researchers. Discrepancies were resolved by mutual consensus.

DATA SYNTHESIS

Data was analyzed using descriptive statistics.

RESULTS

Three papers reported five children with SNHL following apparent disseminated HSV-2 infections in which other obvious clinical sequelae of HSV infection and co-morbid conditions were present. Audiometric information is lacking regarding onset and progression. There are no reports of delayed-onset SNHL following perinatal or asymptomatic HSV infection.

CONCLUSIONS

The development of SNHL in children with exposure to HSV occurs rarely. Routine serological screening for HSV infection in otherwise healthy neonates newly diagnosed with SNHL is unjustified. There is insufficient data to define the incidence and natural history of SNHL in children with HSV infections. Carefully designed and conducted studies are needed to address this issue.

Neuropsychologic outcomes in children with neonatal herpes encephalitis

Neonatal herpes simplex virus infection with involvement of the central nervous system is a serious disease with high morbidity, even with acyclovir therapy. The disability includes cerebral palsy and different aspects of cognitive dysfunction which are of utmost importance for the child's future habilitation. We conducted a descriptive cohort study to define neuropsychologic outcomes and determine the relationship between neonatal neuroimaging and neuropsychologic outcomes. Among 267,690 children born in the Stockholm area over 12 years (1989-2000), 14 were diagnosed with neonatal herpes including central nervous system involvement. Nine children were neuropsychologically evaluated. Neonatal herpes virus infection had an even greater impact on cognitive function, speech ability, and attention deficit than anticipated. Relapse leading to deterioration was demonstrated in one child. Social skills were influenced to a lesser degree. Neurodevelopmental outcomes of the children were not well-correlated with extent of cerebral damage as visualized by computed tomography at 7-28 days after onset of signs. Neuropsychologic assessment is essential in the habilitation of the child, and a prerequisite for the evaluation of new treatments and for the assessment of deterioration of cerebral function related to relapses.

Clinical and laboratory features of neonatal herpes simplex virus infection: a case-control study

BACKGROUND

Neonatal herpes simplex virus (HSV) infection can cause significant morbidity and mortality but can be difficult to identify, particularly in neonates without vesicular rash.

OBJECTIVE

To determine the unique clinical and laboratory features of neonates with and without HSV infection admitted to Texas Children's Hospital during a 14-year period.

METHODS

An historic case-control study of all hospitalized neonates with laboratory-confirmed HSV infection and a restricted sample (ratio 1:4) of HSV test-negative hospitalized neonates. Univariate and multivariate analyses were performed to identify clinical and laboratory factors associated with neonatal HSV infection.

RESULTS

Forty cases and 160 comparison subjects were identified. The following factors were associated with neonatal HSV infection by univariate analysis: maternal primary HSV infection, maternal fever, vaginal delivery, prematurity, postnatal HSV contact, vesicular rash, hypothermia, lethargy, seizures, severe respiratory distress, hepatosplenomegaly, thrombocytopenia, elevated hepatic enzymes, and cerebrospinal fluid (CSF) pleocyosis and proteinosis. Factors not associated with neonatal HSV infection were fever, total peripheral white blood cell count, and red blood cells in the CSF. For neonates presenting without vesicular rash, maternal fever, respiratory distress requiring mechanical ventilation, and CSF pleocytosis were independently associated with HSV infection.

CONCLUSIONS

Inclusion of the newly appreciated features of maternal fever, respiratory distress, and thrombocytopenia might improve the detection of neonatal HSV infection. Clinical and laboratory factors typically associated with neonatal HSV infection were confirmed to be maternal primary HSV infection, vaginal delivery, prematurity, neonatal seizures, vesicular rash, elevated hepatic enzymes, and CSF pleocytosis.

Herpes Simplex Virus Type 1 infection: overview on relevant clinico-pathological features

Herpes Simplex Virus Type 1 (HSV-1) is a nuclear replicating enveloped virus, usually acquired through direct contact with infected lesions or body fluids (typically saliva). The prevalence of HSV-1 infection increases progressively from childhood, the seroprevalence being inversely related to socioeconomic background. Primary HSV-1 infections in children are either asymptomatic or following an incubation period of about 1 week gives rise to mucocutaneous vesicular eruptions. Herpetic gingivostomatitis typically affects the tongue, lips, gingival, buccal mucosa and the hard and soft palate. Most primary oro-facial HSV infection is caused by HSV-1, infection by HSV-2 is increasingly common. Recurrent infections, which occur at variable intervals, typically give rise to vesiculo-ulcerative lesions at mucocutaneous junctions particularly the lips (herpes labialis). Recurrent HSV-1 infection within the mouth is uncommon in otherwise healthy patients, although in immunocompromised patients, recurrent infection can be more extensive and/or aggressive. The diagnosis of common herpetic infection can usually be based upon the clinical history and presenting features. Confirmatory laboratory diagnosis is, however, required when patients are, or may be, immunocompromised.

The neurotropic herpes viruses: herpes simplex and varicella-zoster

Herpes simplex viruses types 1 and 2 (HSV1 and HSV2) and varicella-zoster virus (VZV) establish latent infection in dorsal root ganglia for the entire life of the host. From this reservoir they can reactivate to cause human morbidity and mortality. Although the viruses vary in the clinical disorders they cause and in their molecular structure, they share several features that affect the course of infection of the human nervous system. HSV1 is the causative agent of encephalitis, corneal blindness, and several disorders of the peripheral nervous system; HSV2 is responsible for meningoencephalitis in neonates and meningitis in adults. Reactivation of VZV, the pathogen of varicella (chickenpox), is associated with herpes zoster (shingles) and central nervous system complications such as myelitis and focal vasculopathies. We review the biological, medical, and neurological aspects of acute, latent, and reactivated infections with the neurotropic herpes viruses.

Expression of toll-like receptors in the healthy and herpes simplex virus-infected cornea

PURPOSE

To study the expression of toll-like receptors (TLRs) in healthy corneas and corneas with active or nonactive herpetic stromal keratitis (HSK).

METHODS

Eight corneas with HSK (including 5 active and 3 nonactive cases) and 8 healthy corneas were evaluated for TLR1-10 mRNA by reverse transcription-polymerase chain reaction (RT-PCR) and relative real-time PCR. The proteins of TLR2, 9 in 3 different groups, were also compared by immunofluorescence staining. The data were analyzed with SPSS 11.5.

RESULTS

TLR1-10 mRNA was expressed in both healthy and HSK corneas. In the healthy cornea, the mRNA expression of TLR1, 2, 3, 4, and 6 was higher, whereas the expression of TLR7, 8, and 9 was lower relative to TLR 5 and 10. All the TLRs mRNA expression in the active HSK corneas were upregulated, especially TLR4, 7, 8, and 9, compared with the healthy corneas. However, in nonactive HSK corneas, only TLR7 mRNA expression upregulated, whereas the others downregulated. The immunofluorescence staining showed that the expression of TLR 9 was slightly stronger in the cornea with active HSK than that of nonactive and healthy corneas.

CONCLUSIONS

TLRs are expressed diversely in the healthy cornea and could have an important role in innate corneal immunity. TLR4, 8, and 9 may be implicated in the pathogenesis of active HSV infection in the cornea, whereas TLR7 may play a key role in HSK whether it is active or not.

Novel recombinant ELISA assays for determination of type-specific IgG antibodies against HSV-1 and HSV-2

The two novel Novagnost enzyme-linked immunosorbent assays (ELISA, Dade Behring) based on recombinant viral glycoprotein G were evaluated for determination of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) IgG. ELISA and immunoblot procedures approved by the US Food and Drug Administration served as the reference for selecting different serum panels to be tested. The sensitivity and specificity of the novel assay for HSV-1 IgG were 93.1-98.0% and 99.3-100%, respectively, while the sensitivity and specificity of the novel assay for HSV-2 IgG were 100% and 94.6-97.6%, respectively. Using Kappa statistics, the Kappa indices were computed at 0.93-0.98 for the HSV-1 assays and 0.92-0.96 for the HSV-2 assays suggesting an almost perfect agreement between the novel ELISAs and the reference tests. In conclusion, the novel immunoassays for determination of HSV-1 or HSV-2 IgG can be recommended for the reliable type-specific diagnosis of HSV infections.

Disseminated neonatal herpes caused by herpes simplex virus types 1 and 2

Disseminated neonatal herpes simplex virus (HSV) infection is characterized by progressive multiple organ failure and high mortality rates. It can result from infection with either HSV-1 or HSV-2. We report a case of disseminated neonatal herpes that was caused by HSV-1 and HSV-2.

Herpes simplex virus infections of the newborn

Herpes simplex virus (HSV) infections are fortunately quite rare in the neonatal population. Nevertheless, due to their life-threatening nature and the tremendous damage that surviving infants can incur, neonatal HSV is actually considered in a differential diagnosis relatively commonly. The availability of safe and effective antiviral therapy for the management of neonatal HSV also can accelerate a clinician's decision to consider HSV as the cause of a neonate's disease presentation, and then to obtain appropriate diagnostic studies and empirically institute antiviral treatment. Decisions on whether to continue antiviral therapy for a full course are predicated on the appropriate interpretation of these diagnostic studies as they subsequently are reported to the treating physician. For HSV-infected neonates, the duration of parenteral acyclovir therapy ranges from 14 to 21 days, depending on the extent of disease. Use of subsequent oral suppressive antiviral therapy is under investigation in randomized controlled trials, and at this time cannot be routinely recommended. This article will summarize the current state of neonatal HSV disease presentation, diagnosis, and management.

Diagnosis of herpes simplex virus infections of the CNS

Advances in the diagnosis of herpes simplex virus infections of the CNS have occurred rapidly over the past 10 years. The development and application of PCR technology to the detection of herpes simplex virus DNA from cerebrospinal fluid has resulted in tremendous improvements in the management of patients with suspected herpes simplex virus CNS infections, not the least of which is decreasing the necessity for invasive brain biopsy to establish the diagnosis. The pace of discovery has continued in recent years with the development of more rapid DNA amplification techniques that do not require postamplification analysis using amplified products (real-time PCR). However, despite the power of these new diagnostic modalities, test results must always be considered in the context of the patient, and physician judgment should never be usurped by technological advances. This article will summarize the advances in the diagnosis of herpes simplex virus CNS disease within the context of how these advances can enhance the care of individual patients.

Herpes simplex and varicella-zoster virus infections during pregnancy: current concepts of prevention, diagnosis and therapy. Part 1: Herpes simplex virus infections

Primary herpes simplex virus (HSV) infection may lead to severe illness in pregnancy and may be associated with transplacental virus transmission and fetal infection. The consequences may be abortion, stillbirth and congenital malformations. In neonates, the clinical findings after intrauterine HSV infection are characterized by skin lesions, diseases of the eye and neurologic damage. Herpes genitalis of pregnant women at the time of labor may result in life-threatening neonatal herpes. Currently, neither active nor passive immunization is available to prevent HSV infections during pregnancy and in the newborn infant. Therefore, antiviral treatment using aciclovir and/or valaciclovir must be considered in all primary episodes of genital herpes as well as in neonates who show signs of either infection. Clinical herpes lesions of the genitalia and/or positive test for virus detection at the time of delivery are an indication for cesarean section. However, this surgical intervention may be reduced by suppressive treatment of recurrent genital herpes with aciclovir or valaciclovir.

Herpes simplex virus infections in preterm infants

OBJECTIVE

Neonatal herpes simplex virus infections cause significant neonatal mortality and morbidity, but the course and prognosis in preterm infants is not well documented. We performed a retrospective review of herpes simplex virus infections at out institution within the first 30 days after birth in infants who were born at <37 weeks to help better define the symptoms and signs of herpes simplex virus infections in preterm infants and to assist in prognosis.

METHODS

Hospital databases were reviewed to identify culture- or polymerase chain reaction-proven cases of herpes simplex virus-1 or herpes simplex virus-2 infections that occurred in preterm newborns between 1989 and 2003. Maternal and neonatal histories, clinical features, and laboratory results were reviewed systematically.

RESULTS

Ten preterm singletons and a set of twins were infected with herpes simplex virus-2 during the first month after birth. No mother had herpes simplex virus lesions at delivery, but a history of genital herpes simplex or other sexually transmitted infections was prevalent among the mothers. Infants presented with either disseminated disease or encephalitis. All infants with disseminated disease (n = 9) died, whereas the 3 infants with encephalitis survived. All infants in the cohort developed respiratory distress, and consistent with the prominence of respiratory symptoms, viral cultures of the respiratory tract were consistently positive. Ten of 12 infants received acyclovir, but despite treatment within 48 hours of symptoms, infants with disseminated disease deteriorated rapidly and died. Two of 3 infants who received high-dosage (60 mg/kg per day) acyclovir survived.

CONCLUSIONS

Herpes simplex virus infections in preterm infants usually present during the first 2 weeks of life with respiratory distress and a high incidence of disseminated disease. Viral respiratory cultures have a high yield for documentation of infection. The morbidity of herpes simplex virus in this population may be attributable to a relatively immature immune system in this population. Additional studies are necessary to delineate the evolution of herpes simplex virus disease in preterm infants and the role of antiviral therapy in mitigating the sequelae of herpes simplex virus infections in this population.

Seroprevalence of herpes simplex virus type 1 and type 2 in Turkey

BACKGROUND

Herpes simplex virus (HSV) infections are among the most common infectious diseases in humans. The prevalence of herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) varies widely across the world. HSV-2 infection is the primary cause of genital herpes. It is highly prevalent in human populations in many parts of the world, and is the most common cause of genital ulcer disease worldwide. In spite of the large prevalence and growing incidence of herpes simplex infection (HSV-1 and HSV-2), relatively few data have been published regarding the seroprevalence of herpes simplex infection, while no data exist regarding the Turkish population.

METHODS

We aimed to investigate the prevalence of HSV-1 and HSV-2 in selected populations in Turkey. A cross-sectional study was conducted involving 2082 serum samples of 725 adults, 300 pregnant women, 200 blood donors, 483 sex workers and 110 patients with genital warts and 264 hotel staff in Istanbul, Turkey. All serum samples were assessed for HSV1 and HSV-2 IgG antibodies using an HSV-type specific, enzyme-linked immunosorbent assay (ELISA).

RESULTS

The prevalence of HSV-2 and HSV-1 antibodies was 4.8 and 85.3% in sexually active adults; 5.5 and 96% in blood donors; 5 and 98% in pregnant women, 17.3 and 93.6% in patients with genital warts; 8.3 and 97.3% in hotel staff; and 60% and 99% in sex workers.

CONCLUSION

These results confirm a higher prevalence of HSV infection than estimated, especially in high risk groups in Turkey. The high prevalence of HSV infection underlines the need for education among these populations.

Antenatal Herpes Serologic Screening

OBJECTIVE

Calls for universal antenatal type-specific herpes simplex virus (HSV) screening to prevent neonatal herpes have recently increased and would affect the four million pregnant women and their partners annually in the United States. We undertook this review to assess the appropriateness of such screening, making relevant comparisons to established antenatal human immunodeficiency virus (HIV) and hepatitis B virus (HBV) screening programs.

DATA SOURCES

We conducted a full PubMed and bibliographic search for relevant literature in English available from 1966 through February 2006, using the terms "genital herpes," "neonatal herpes," "decision analysis" or "cost-effectiveness analysis," and "herpes and pregnancy" or "antenatal herpes screening." Comparison literature was obtained by replacing "herpes" with "HBV" or "HIV".

METHODS OF STUDY SELECTION

We appraised antenatal type-specific HSV screening using well-established criteria for a good screening program, which we articulated as questions. Of 455 articles we selected those that addressed at least one of the questions and were pertinent to the U.S. population.

TABULATION, INTEGRATION, AND RESULTS

We found that neonatal HSV is rare and its incidence is imprecisely defined. There is a lack of evidence supporting the effectiveness of interventions to prevent maternal acquisition of new infection in late pregnancy, which accounts for 60-80% of neonatal herpes. The consequences of universal screening are incompletely understood but include the potential for unnecessary cesarean deliveries and medical treatment, maternal psychosocial stress, and discord among partners. The available evidence indicates universal screening is not cost-effective. In contrast, antenatal HIV and HBV screening programs better satisfy accepted criteria for screening.

CONCLUSION

On the basis of this appraisal, universal antenatal type-specific HSV screening to prevent neonatal herpes does not adequately satisfy criteria of a good screening program, and we recommend against its adoption.

Valacyclovir prophylaxis to prevent recurrent herpes at delivery: a randomized clinical trial

OBJECTIVE

To measure the efficacy of valacyclovir suppression in late pregnancy to reduce the incidence of recurrent genital herpes in labor and subsequent cesarean delivery.

METHODS

A total of 350 pregnant women with a history of genital herpes were assigned randomly to oral valacyclovir 500 mg twice a day or an identical placebo from 36 weeks of gestation until delivery. In labor, vulvovaginal herpes simplex virus (HSV) culture and polymerase chain reaction (PCR) specimens were collected. Vaginal delivery was permitted if no clinical recurrence or prodromal symptoms were present. Neonatal HSV cultures and laboratory tests were obtained, and infants were followed up for 1 month after delivery. Data were analyzed using chi2 and Student t tests.

RESULTS

One hundred seventy women treated with valacyclovir and 168 women treated with placebo were evaluated. Eighty-two percent of the women had recurrent genital herpes; 12% had first episode, nonprimary genital herpes; and 6% had first episode, primary genital herpes. At delivery, 28 women (8%) had recurrent genital herpes requiring cesarean delivery: 4% in the valacyclovir group and 13% in the placebo group (P = .009). Herpes simplex virus was detected by culture in 2% of the valacyclovir group and 9% [corrected] of the placebo group (P =.02). No infants were diagnosed with neonatal HSV, and there were no significant differences in neonatal complications. There were no significant differences in maternal or obstetric complications in either group.

CONCLUSION

Valacyclovir suppression after 36 weeks of gestation significantly reduces HSV shedding and recurrent genital herpes requiring cesarean delivery.

LEVEL OF EVIDENCE

I.

Transgenic reporter mouse for bioluminescence imaging of herpes simplex virus 1 infection in living mice

Bioluminescence imaging allows spatial and temporal progression of viral infection to be detected and quantified in living mice, thereby providing a new approach for studies of viral-host pathogenesis. It has been necessary to construct and validate recombinant reporter viruses that express firefly luciferase to investigate viral replication and spread with this imaging technology. This strategy greatly limits the ability to analyze multiple strains of virus and/or existing viral mutants, and reporter viruses also may be attenuated relative to the respective parental viruses. To facilitate bioluminescence imaging of herpes simplex virus type 1 (HSV-1), we developed a transgenic reporter mouse that uses the promoter from HSV-1 thymidine kinase to control expression of firefly luciferase. Infection with HSV-1 activated expression of firefly luciferase in corneal and flank models of infection, and amounts of bioluminescence increased in proportion to increasing input titers of virus. Imaging could detect infection with three different strains of HSV-1 with the following relative rank order of bioluminescence produced at the site of infection: McKrae > 17 > KOS. Corneal infection with as few as 1 x 10(3) pfu strain McKrae was detectable above background levels. By comparison, infection with vaccinia virus did not affect bioluminescence in the reporter mouse. Collectively, these data establish a new transgenic reporter mouse for infection with HSV-1, thereby enabling in vivo bioluminescence imaging studies of HSV-1 pathogenesis without constructing new reporter viruses.

Hematogenous vertical transmission of herpes simplex virus type 1 in mice

Herpes simplex virus type 1 (HSV-1) is a neurotropic virus that causes severe disease and death in newborn humans but, to date, it remains unclear how neonatal infection occurs. We show here that the vertical transmission of HSV-1 in mice is mainly hematogenous and involves the colonization of the neonate central nervous system (CNS). HSV-1 DNA was mainly detected in the blood and CNS of the offspring born to latently infected mothers; no significant differences were seen between the viral DNA concentrations in the blood of these mothers and their female progeny (either neonate or adult). The administration of acyclovir during gestation reduced or eliminated both the maternal and the neonatal viral DNA in the blood. Embryo transfer was performed to ensure (as far as possible) that only vertical hematogenous infection took place. Immunohistochemical analysis detected viral proteins in the encephalon of the offspring. Immunofluorescence studies provided immunoreactive evidence of HSV-1 proteins in the neurons of the hippocampus and showed that these viruses can molecularly reactivate after hyperthermia. Neonatal HSV-1 infection therefore appears to be mainly caused by hematogenous vertical transmission, and the viruses that colonize the offspring CNS are capable of molecular reactivation after a period of latency.

Fatal outcome of herpes simplex virus type 1-induced necrotic hepatitis in a neonate

In neonates, herpes simplex virus (HSV) infections can lead to severe diseases associated with high mortality. We report a 6-day-old girl who developed clinical signs of fulminant hepatic failure accompanied by infectious-toxic shock and disseminated coagulopathy secondary to HSV type 1 (HSV-1) infection. The diagnosis was performed postmortem by demonstration of HSV-1 DNA in liver tissue as well as by retrospective detection of HSV-specific antibodies.

Prenatal diagnosis of an exceptional intrauterine herpes simplex type 1 infection

OBJECTIVE

To assess ultrasound findings of a fetus with intrauterine growth retardation (IUGR) and skin damage, related to intrauterine herpes simplex virus (HSV) infection.

METHODS

A 23-year-old, G1, P0 woman was referred at 23.5 weeks' gestation (WG) for IUGR. The patient had a previous single episode of serotype 1 herpes progenitalis at 11 WG. Ultrasound examination revealed extensive skin changes with no cerebral involvement. The methods employed for evaluation of the disease included maternal serology, amniocentesis and repeated ultrasound examinations.

RESULTS

Maternal serology was positive for HSV1 and fetal infection was confirmed via polymerase chain reaction (PCR). At 27 WG, amniotic fluid index decreased and lower limb skin as well as abdominal skin was irregular. Oesophagus was thickened. In contrast, upper limb skin and cranial vault were thin and less visible. IUGR was predominant as regards bone parameters. After termination of pregnancy, the fetus showed macroscopic characteristics of HSV infection. Microscopic examination revealed only placental and skin lesions.

CONCLUSIONS

Our report illustrates a rare case of HSV1 intrauterine infection that occurred during the first trimester with bone and cephalic IUGR associated with extensive skin damage, and with no cerebral involvement.

Empiric Acyclovir Is Infrequently Initiated in the Emergency Department to Patients Ultimately Diagnosed With Encephalitis

STUDY OBJECTIVE

We evaluate the frequency of empiric acyclovir administration to patients in the emergency department (ED) who are ultimately diagnosed with encephalitis.

METHODS

We conducted an explicit retrospective medical record review of consecutive patients discharged with a final diagnosis of herpes simplex encephalitis or viral encephalitis not otherwise specified for the period 1993 to 2003. The frequency of ED administration of empiric acyclovir was measured for patients who met the inclusion criteria of fever, neuropsychiatric abnormality, and cerebrospinal fluid pleocytosis with a negative Gram's stain result in the ED.

RESULTS

Of the 90 patients reviewed, 24 (27%) met the inclusion criteria of fever, neuropsychiatric abnormality, and cerebrospinal fluid pleocytosis with a negative Gram's stain result in the ED. Of these 24 patients, 7 (29%) received empiric acyclovir in the ED, 6 (86%) patients after cerebrospinal fluid results were available, with a median time to administration of 1.5 hours (95% confidence interval [CI] 0 to 3.1 hours). The remaining 17 (71%) patients did not receive acyclovir in the ED, with median times of 16 hours (95% CI 7.5 to 44 hours) before initiation of acyclovir in inpatient settings.

CONCLUSION

The majority of patients in our institution who were ultimately diagnosed with encephalitis did not receive empiric acyclovir in the ED, despite clinical presentations consistent with encephalitis.

Epstein-Barr virus infection during pregnancy and the risk of adverse pregnancy outcome

OBJECTIVES

To study the association between Epstein-Barr virus (EBV) antibody status in early pregnancy and pregnancy outcomes including fetal death, length of gestation and fetal weight and length at birth.

DESIGN

Nested control study.

SETTING

Population based health registers.

POPULATION

The source population comprised 35,940 pregnant women. Cases were all (280) women with fetal death and a random sample of 940 women with a live born child.

METHOD

Information on pregnancy outcome was obtained from the Norwegian Medical Birth Registry. Serum samples from the first trimester were tested for EBV antibodies. In women seronegative for EBV, further serum from late pregnancy was analysed to detect seroconversion. Main outcome measures Vital status, length of gestation, weight and length at birth.

RESULTS

There was no association between EBV antibody status and fetal death. Women with significant EBV reactivation had a significantly shorter duration of pregnancy, and associated lighter babies, compared with women without significant reactivation (stillborn: 176 vs 197 days, P=0.16, and live born: 271 vs 279 days, P=0.03, respectively).

CONCLUSION

Significant reactivation of EBV infection during pregnancy may influence pregnancy duration.

Genital Herpes Complicating Pregnancy

Approximately 22% of pregnant women are infected with herpes simplex virus (HSV)-2, and 2% of women will acquire HSV during pregnancy. Remarkably, up to 90% of these women are undiagnosed because they are asymptomatic or have subtle symptoms attributed to other vulvovaginal disorders. Diagnosis of genital herpes relies on laboratory confirmation with culture or polymerase chain reaction assay of genital lesions and type-specific glycoprotein G-based serologic testing. Neonatal herpes is the most severe complication of genital HSV infection and is caused by contact with infected genital secretions at the time of labor. Maternal acquisition of HSV in the third trimester of pregnancy carries the highest risk of neonatal transmission. Despite advances in the diagnosis and treatment of neonatal herpes, little change in the incidence or serious sequelae from this infection has occurred. As such, prevention of the initial neonatal infection is critically important. Obstetricians are in a unique position to prevent vertical HSV transmission by identifying women with genital lesions at the time of labor for cesarean delivery, prescribing antiviral suppressive therapy as appropriate, and avoiding unnecessary invasive intrapartum procedures in women with genital herpes. Enhanced prevention strategies include identification of women at risk for HSV acquisition during pregnancy by testing women and possibly their partners for HSV antibodies and providing counseling to prevent transmission to women in late pregnancy.

Herpes Simplex Virus Infections in Neonates and Early Childhood

Of the commonly considered congenital infections, those caused by cytomegalovirus (CMV), syphilis, and herpes simplex virus (HSV) are frequently (CMV, HSV) or exclusively (syphilis) acquired sexually by the mother, with subsequent transmission to the developing fetus. Of the other commonly considered congenital infections, including rubella and toxoplasma infections, the mother is exposed to the infectious agent via interpersonal or environmental contacts. Unlike each of these other pathogens, which are transmitted transplacentally to the developing fetus following maternal infection though, HSV usually is transmitted perinatally as the neonate is exposed to the virus during passage through an infected birth canal. This difference in timing of acquisition of infection has had important consequence in the therapeutic advances achieved during the last 30 years in the management of neonatal HSV infections. Because the time period between the acquisition of infection and initiation of effective antiviral therapy is shorter in neonatal herpes than in congenital toxoplasmosis or CMV infections, the outcomes of therapy have the potential to be markedly different. This article will summarize the current state of neonatal HSV disease presentation, diagnosis, and management.

Maternal infection and adverse fetal and neonatal outcomes

Adverse pregnancy outcomes can follow direct placental, fetal, or neonatal infection, or preterm birth associated with vaginal, cervical, intrauterine, or even nonpelvic infections. These latter infections appear to be associated with the majority of very early preterm births, and may explain some of the long-term neurologic damage associated with preterm birth. Bacterial vaginosis and its associated intrauterine infections likely contribute far more to the overall burden of adverse pregnancy outcomes than the more classical perinatal infections such as rubella and syphilis.

Pediatric central nervous system infections and inflammatory white matter disease

This article reviews the immunology of the central nervous system and the clinical presentation, diagnosis, and treatment of children with viral or parainfectious encephalitis. The emphasis is on the early recognition of treatable causes of viral encephalitis (herpes simplex virus), and the diagnosis and treatment of acute disseminated encephalomyelitis are described in detail. Laboratory and imaging findings in the two conditions also are described.

[The skin as an expression of neurological alterations in the neonate]

The skin is involved in many different genetic syndromes and diseases with multiple organ involvement. Neurodevelopmental disorders appear in many of these entities and knowledge of these cutaneous alterations may provide clues to their diagnosis. Recognizing these skin disorders in the newborn allows early identification of neonates with a biological risk of epilepsy and motor and/or cognitive disorders and enables them to be followed up. This helps to plan the management of these patients and, in many entities, to predict their natural history and provide genetic counseling to the family. This review examines the cutaneous signs that may provide important clues in the neonate that help to identify entities that carry a risk of neurodevelopmental disorders in the neonate.

Herpes simplex virus encephalitis during suppressive therapy with acyclovir in a premature infant

Cutaneous herpes simplex virus type 2 (HSV-2) infection was recognized at 19 days of age in a 1415-g female infant born at 31 weeks of gestation. Cerebrospinal fluid (CSF) HSV polymerase chain reaction (PCR) was negative, and MRI of the brain was normal. After a 14-day course of high-dose intravenous acyclovir, the infant developed a cutaneous recurrence at 38 days of age. CSF HSV PCR again was negative. She was subsequently begun on oral acyclovir to prevent cutaneous reactivation of HSV. At 3 months of age, the infant developed HSV encephalitis as manifested by fever, seizures, abnormal CSF indices, abnormal brain MRI, and positive CSF HSV PCR. No cutaneous disease was present. It is not known whether the HSV encephalitis in our patient represented reactivation of previously unrecognized central nervous system infection or new onset of central nervous system disease as a result of spread from other tissue or site to the brain. The failure of oral acyclovir to prevent such an occurrence, however, highlights gaps in our understanding of the pathogenesis of neonatal HSV disease and questions the use of acyclovir suppression to prevent neurologic sequelae.

Life-threatening cutaneous conditions in neonates

One of the major medical concerns in neonates is their vulnerability to life-threatening complications. Early diagnosis of potentially serious medical conditions is essential in prevention of such complication by prompt administration of appropriate treatments. Recognition of cutaneous manifestations of potentially fatal diseases may assist a clinician in management of newborns. To overview the full spectrum of this category of conditions, Medline search was performed for cases of cutaneous manifestations associated with mortality during the first month of live that were published in the English language literature since 1977. This is a concise review of the clinical aspects of most of the potentially life-threatening disorders in neonates divided by basic morphology of their cutaneous manifestations.

Improved neurodevelopmental outcomes following long-term high-dose oral acyclovir therapy in infants with central nervous system and disseminated herpes simplex disease

OBJECTIVE

Infants with neonatal herpes, classified as central nervous system or disseminated disease, have a high incidence of moderate and severe neurologic deficits despite standard acute therapy.

STUDY DESIGN

Following completion of parenteral therapy, infants with central nervous system and/or disseminated disease received 2 years of continuous oral acyclovir therapy. Target minimum peak serum acyclovir concentrations were >2 microg/ml for the first three patients, and >3 microg/ml for the subsequent 13 patients. Safety assessments were made every 3 months. We evaluated neurodevelopmental outcomes with Bayley Scales of Infant Development.

RESULTS

A total of 16 consecutive herpes simplex virus-infected infants born during 1990 to 2003 received the treatment plan; 13/16 infants had central nervous system disease; 3 had disseminated disease without central nervous system involvement. A total of 69% (11/16) had Bayley scores in the normal range for mental development and 79% (11/14) had motor scores in the normal range. At the final assessment, five children had developmental delays. One child had severe mental delay with normal motor development. Four children had mild mental delays, with severe motor delays in three. All children were independently mobile, without seizure disorder, had normal vision, and had speech development. During the 2-year course of treatment, five children had brief recurrences of dermal lesions, and none had evidence of neurologic deterioration. There were no serious or sustained adverse drug reactions.

CONCLUSION

This pilot study reports improved outcomes in a small cohort of infants with a prolonged course of oral acyclovir. A minority of these children exhibited mild or significant developmental delays. Further investigation of this approach to treatment is warranted.

Neonatal herpes: What have we learned

Neonatal herpes simplex virus (HSV) infection usually is acquired during the birth process, as the neonate comes in contact with the virus during passage through an infected birth canal. After an incubation period which can last as long as 2 to 4 weeks, neonatal HSV disease then manifests in 1 of 3 ways: (1) disseminated disease, with visceral organ involvement (including infection of the brain in two-thirds to three-quarters of patients); (2) central nervous system disease (with no other visceral organ involvement, but with skin lesions in two-thirds of patients); or (3) disease limited to the skin, eyes, and/or mouth (ie, SEM disease). Diagnostic advances in recent years have focused primarily on applying polymerase chain reaction technology to babies suspected of having neonatal HSV disease. Treatment of neonatal HSV disease with intravenous acyclovir has improved the likelihood of survival substantially, although neurologic morbidity remains a common sequelae, especially among survivors of central nervous system disease. Despite these advances, the duration of time from onset of symptoms and initiation of antiviral therapy has remained unchanged for the past 20 years. The surest way to improve outcomes rapidly at this point is to raise awareness of neonatal HSV disease, resulting in the establishment of earlier diagnoses and more rapid institution of antiviral therapy. In the longer term, development of a bedside nucleic acid detection kit for real-time detection of HSV DNA in the maternal genital tract at the time of delivery could identify which babies are at risk of developing neonatal HSV disease.

Growth of herpes simplex virus in epidermal keratinocytes determines cutaneous pathogenicity in mice

Herpes simplex viruses (HSV)-1 and -2 isolated from genital lesions were examined for cutaneous pathogenicity and its correlation with cellular tropism. HSV-1 caused vesiculation, erosion/ulcer, and zosteriform lesions successively, but skin lesions of HSV-2 developed without vesiculation in some mice, and with statistically significantly less frequent vesiculation than HSV-1. Thus, the virological type of HSV was correlated with its cutaneous pathogenicity. The growth characteristics of HSV-1 and -2 were compared in cultured human embryonic lung (HEL) fibroblasts, human lung cancer A549 cells, human neonatal epidermal keratinocytes, human neonatal dermal fibroblasts, HeLa cells, and Vero cells. HSV-2 produced plaques that were 72% times the size of HSV-1 plaques in epidermal keratinocytes but 230%-500% the size in the other cells. The difference between HSV-1 and -2 in the ratio of plaque size to virus yield in epidermal keratinocytes was much larger (502 times) than the ratio of the other cells (5.57-28.8 times). Keratinocytes are the major constituent of the epidermal layer of the skin and the cells in which vesiculation and erosion/ulceration occur histologically. Therefore, the smaller spread of HSV-2 in keratinocytes of the epidermal layer and the greater spread in other cells of the dermal layer might reflect its lesser invasiveness in the epidermal layer despite larger invasiveness in the dermal layer, which is reflected in the low incidence of erosion/ulcer of the skin compared to HSV-1. Thus, the growth of HSV in epidermal keratinocytes appeared to correlate with the cutaneous pathogenicity causing vesiculation in the skin.

Management of neonatal herpes simplex virus infections

As many as 2,500 infants develop neonatal herpes each year, most of whom are born to women with no history or physical findings suggestive of genital herpes. Infection usually takes one of three forms: 1) disease localized to skin, eyes, and mucous membranes, 2) localized central nervous system infection, or 3) disseminated infection. Exposure to the virus occurs during passage through an infected birth canal, but 5% of infants acquire the infection in utero. The mortality rate is 31% for disseminated infection and 6% for localized central nervous system disease; long-term neurologic sequelae are seen in 17% and 70% of survivors, respectively. Diagnosis is made by isolating of the virus from skin lesions or other involved sites. The polymerase chain reaction for the detection of viral DNA in cerebrospinal fluid or serum is now the diagnostic test of choice for central nervous system or disseminated neonatal herpes because it has higher sensitivity than traditional culture methods. Treatment is with high-dose intravenous acyclovir (60 mg/kg per day in three divided doses), with adjustments made for infants with renal or hepatic insufficiency. Supportive measures and neuroimaging studies are often required. Acyclovir is administered for three weeks, but infants with disease localized to the skin, eyes, and mucous membranes can be treated for two weeks if the cerebrospinal fluid polymerase chain reaction assay is negative for herpes simplex virus DNA. Prevention of infection in infants can be accomplished by cesarean delivery when women have active lesions at the onset of labor. Neonates delivered through an infected birth canal should be screened between 24 and 48 hours of age with viral cultures of eyes, nasopharynx, mouth, and rectum. If positive, they should be treated with acyclovir even if asymptomatic. Suppressive acyclovir therapy beginning at 36 weeks gestation is often prescribed for women with frequent recurrences of genital herpes.

Impact of maternal stress on the transmammary transfer and protective capacity of herpes simplex virus-specific immunity

In adults, psychological stress regulates immune responsiveness in part via the increased levels of corticosterone that are produced as a result of hypothalamic-pituitary-adrenal (HPA) axis activation. However, there is a lack of knowledge as to the role such regulation may play in the neonate. Neonates are severely compromised in their ability to generate an immune response to pathogens encountered after birth and therefore rely heavily on maternally derived antibody acquired postnatally through the milk. This passive transfer of antibody is critical for protection of the neonate from severe herpes simplex virus (HSV) infection and mortality. Using a well-established postnatal restraint/light stress model, we determined whether maternal stress and the associated increases in corticosterone would affect the transmammary transfer of antibody and subsequent neonate susceptibility to HSV-associated mortality. Serum corticosterone levels were markedly increased in lactating mice subjected to the restraint/light stress, and increased levels of corticosterone were transferred through the milk of these stressed mothers to their neonates. Despite these increases in corticosterone, the transmammary transfer and accumulation of total and HSV-specific IgG in neonate serum remained intact. This milk-derived, HSV-specific antibody alone protected the neonate from systemic viral spread. Interestingly, postnatal maternal stress significantly increased neonate survival after HSV-2 infection despite no apparent alteration in viral spread. These studies demonstrate that although the transmammary transfer of antibody is unaffected by maternal stress, stress may be enhancing components of antiviral immunity that are effective in protecting neonates from HSV-associated mortality.

Postpartum maternal corticosterone decreases maternal and neonatal antibody levels and increases the susceptibility of newborn mice to herpes simplex virus-associated mortality

The effects of corticosterone on the transmammary transfer of herpes simplex virus (HSV)-specific antibody and the ability of the neonate to survive HSV-2 infection were assessed. Increased postpartum maternal corticosterone reduced the levels of total and HSV-specific IgG in the serum and milk of mothers. Neonates nursed by these mothers received increased levels of corticosterone and decreased levels of total and HSV-specific IgG. Accordingly, these neonates were more susceptible to HSV-2-associated mortality; however, survival was restored through passive immunization with HSV-specific antibody. These studies demonstrate that postpartum elevations in corticosterone compromise a mother's ability to provide protective antibody to their offspring.

Neonatal herpes simplex infection

Tremendous advances have occurred over the past 30 years in the diagnosis and management of neonatal herpes simplex virus (HSV) disease. Mortality in patients with disseminated disease has decreased from 85 to 29%, and that in patients with central nervous system (CNS) disease has decreased from 50 to 4%. Morbidity has been improved more modestly: the proportion of patients with disseminated disease who are developing normally at 1 year has increased from 50 to 83%. While the proportion of patients with neurologic morbidity following CNS disease has remained essentially unchanged over the past three decades, the total number of patients who are developing normally following HSV CNS disease has increased due to the improved survival. Although additional therapeutic advances in the future are possible, more immediate methods for further improvements in outcome for patients with this potentially devastating disease lie in an enhanced awareness of neonatal HSV infection and disease. A thorough understanding of the biology and natural history of HSV in the gravid woman and the neonate provides the basis for such an index of suspicion and is provided in this article.

Intravaginal administration of herpes simplex virus type 2 to mice leads to infection of several neural and extraneural sites

Female mice have been used extensively to study mucosal immunity against herpes simplex virus type 2 (HSV-2) infection of the vagina, but comparatively little is known about the spread of this virus to other tissues. Here the authors have used immunolabeling to demonstrate that HSV-2 infected the vaginal epithelium; the epithelium covering the vulva, perineum, and anal canal; and perineal hair follicles and sebaceous glands. The kinetics and basal localization of the immunolabeling indicated that the virus spread horizontally within the epithelial layer, starting in the vagina and then proceeding to the distal epithelial sites. HSV-2 also spread from the vagina to multiple neuronal sites including the paracervical ganglia (PCG), which are the major autonomic ganglia of the pelvis. The authors demonstrated both sympathetic and parasympathetic neurons in the PCG by labeling of acetylcholinesterase and tryosine hydroxlyase, and noted that infection was limited mainly or entirely to parasympathetic neurons. Infection of the PCG was correlated with the presence of virus in the autonomic ganglia in the walls of the rectum and urinary bladder, which in turn correlated with distention of these organs and retention of urine and feces. HSV-2 infection was also detected in cell bodies and axons in the lumbosacral sympathetic chain, in lumbosacral dorsal root ganglia, and in the dorsal portions of the lumbar spinal cord. Collectively, the data show that vaginal HSV-2 infection in mice leads to subsequent infection of multiple neural and epithelial sites. This information should be useful for development of a mouse model that can be used to study HSV-2 latency and for development of therapeutic vaccines to prevent recurrent infections.

Herpes simplex virus 1 interaction with Toll-like receptor 2 contributes to lethal encephalitis

Human neonates infected with herpes simplex virus 1 (HSV-1) develop one of three distinct patterns of infection: (i) infection limited to the skin, eye or mouth; (ii) infection of the CNS; or (iii) disseminated infection. The disseminated form usually involves the liver, adrenal gland, and lung, and resembles the clinical picture of bacterial sepsis. This spectrum of symptoms in HSV-1-infected neonates suggests that inflammatory cytokines play a significant role in the pathogenesis of the disease. Recent studies suggest that the Toll-like receptors (TLRs) may play an important role in the induction of inflammatory cytokines in response to viruses. TLRs are mammalian homologues of Toll, a Drosophila protein that is essential for host defense against infection. Engagement of TLRs by bacterial, viral, or fungal components leads to the production and release of cytokines and other antimicrobial products. Here, we demonstrate that TLR2 mediates the inflammatory cytokine response to HSV-1 by using both transfected cell lines and knockout mice. Studies of infected mice revealed that HSV-1 induced a blunted cytokine response in TLR2(-/-) mice. Brain levels of monocyte chemoattractant protein 1 chemokine were significantly lower in TLR2(-/-) mice than in either wild-type or TLR4(-/-) mice. TLR2(-/-) mice had reduced mortality compared with wild-type mice. The differences between TLR2(-/-) mice and both wild-type and TLR4(-/-) mice in the induction of monocyte chemoattractant protein 1, brain inflammation, or mortality could not be accounted for on the basis of virus levels. Thus, these studies suggest the TLR2-mediated cytokine response to HSV-1 is detrimental to the host.

Current treatment options to prevent perinatal transmission of herpes simplex virus

Neonatal herpes is a potentially devastating consequence of perinatal transmission of the herpes simplex virus (HSV), with significant morbidity and mortality. Treatment options are available, but must begin early in disease with manifestations that are often protean. Thus, preventive measures need to be optimised. Antiviral suppression in late pregnancy of women with a history of recurrent genital herpes will decrease symptomatic recurrence at delivery and appears to reduce caesarian section rates. However, primary HSV Type 2 and primary HSV Type 1 episodes have the highest neonatal transmission rates and thus, effective prevention may require the identification and suppression of the discordant partner. Significant experience has been gained with the use of acyclovir in pregnancy and it is recommended for both episodic and suppressive therapy in pregnant women. Its use has been demonstrated to be cost-effective in suppressive therapy, although issues regarding compliance and the potential for neonatal neutropenia need to be addressed. The more conveniently dosed prodrugs valacyclovir and famciclovir are being evaluated for use in pregnancy.

Molecular diagnosis of viral infections of the central nervous system

The development of techniques for the amplification of DNA and RNA opened the way for the creation of extremely specific, sensitive, and rapid diagnostic tests for the detection of viral infections of the central nervous system. Polymerase chain reaction (PCR) and reverse transcription PCR diagnostic assays have revolutionized the approach to the diagnosis of important viral pathogens--in particular, enteroviruses (EVs), herpes viruses, and JC virus (JCV). These molecular approaches to diagnosis have led to improvements in clinical outcome and patient care. Additionally, their use has permitted a better understanding of the natural history and clinical spectrum of the syndromes caused by these important human pathogens. This article summarizes the current understanding with regard to the available, molecularly based, diagnostic assays for the detection of EVs, herpes viruses, and JCV.

Relapse of neonatal herpes simplex virus infection

BACKGROUND

Neonatal herpes simplex virus (HSV) infection is a severe disease with high mortality and morbidity. Recurrence of skin vesicles is common.

OBJECTIVE

To determine the features of relapse and identify the factors related to relapse.

DESIGN

Thirty two surviving patients with neonatal herpes virus infections were enrolled. All patients received acyclovir treatment. Clinical and virological data were analysed and compared between relapsed and non-relapsed cases.

RESULTS

Thirteen (41%) had either local skin or central nervous system relapse between 4 and 63 days after completing the initial antiviral treatment. Nine patients exhibited local skin relapses, and four developed central nervous system relapses. In one skin and two central nervous system relapse cases, neurological impairment later developed. Type 2 virus infection was significantly related to relapse (odds ratio 10.4, 95% confidence interval 1.1 to 99.0). Patients with relapse had worse outcomes than those without relapse.

CONCLUSION

Neonates with HSV type 2 infections have a greater risk of relapse. Relapsed patients have poorer prognoses.

Nongenetic causes of hearing loss

Nongenetic as well as genetic etiologies must be explored in the child with identified hearing loss. Graduates of the neonatal intensive care unit are at increased risk for developing hearing loss due to hypoxia, hyperbilirubinemia, very low birth weight, and ototoxic medications. Although meningitis has decreased in frequency, it is still a risk factor for hearing loss. Cytomegalovirus remains the most common congenital infection and a relatively common etiology of hearing loss, which can be progressive. Preventable causes of hearing loss include those caused by head trauma, noise, and ototoxic medications. Identification of the etiology of hearing loss can facilitate the development of a treatment and management plan.