Neonatal herpes simplex virus infections: HSV DNA in cerebrospinal fluid and serum

Rapid diagnosis of herpes simplex virus 1 and 2 bloodstream infections utilizing a sample-to-answer platform

Bloodstream HSV-1 and HSV-2 infections can cause devastating outcomes with high morbidity and mortality, especially in neonates or immunocompromised individuals. Proper patient management for herpes simplex virus (HSV) bloodstream infections is time-sensitive and requires a rapid, accurate, and definitive diagnosis. The absence of the U.S. Food and Drug Administration (FDA)-approved molecular assays for HSV detection in blood, coupled with a lack of consensus on the optimal sample type, underscores the unmet need for improved diagnostics. We prospectively compared the cycle threshold values in paired samples including whole blood (WB), plasma, serum, and peripheral blood mononuclear cells (PBMCs) from patients with bloodstream HSV infections. This analysis employed a modified use of the FDA-cleared Simplexa HSV-1 & 2 Direct assay. The clinical performance in serum was assessed by comparing the results of 247 remnant specimens on this sample-to-answer platform to established laboratory-developed tests in a blinded fashion. Serum samples exhibited significantly lower cycle thresholds than whole blood samples [2.6 cycle threshold (Ct) bias, P < 0.001]. The modified Simplexa assay demonstrated 100% positive percent agreement for the detection of HSV-1 and HSV-2 DNA in serum samples and yielded an overall agreement of 95% (95% CI, 0.92 to 0.97), with a κ statistic of 0.75 (95% CI, 0.62 to 0.86) compared to the composite reference method. Discordance rates were 5.20% for HSV-1 and 0.81% for HSV-2. This investigation demonstrates that serum is an optimal specimen type for HSV detection when compared to several blood compartments. Serum offers a promising sample type for rapid and accurate diagnosis of HSV bloodstream infections using the modified Simplexa assay.

IMPORTANCE

Rapid, accurate, and definitive diagnosis of herpes simplex virus (HSV) infections is crucial in clinical settings for patient management. The absence of FDA-authorized molecular assays for HSV-1/2 detection in blood, coupled with a lack of consensus on the optimal sample type, underscores the need for improved diagnostic methods. Furthermore, rapid diagnosis of HSV bloodstream infections enables timely administration of antiviral treatment, influences patient management decisions for those at high risk, and can contribute to shorter hospital stays, thereby reducing healthcare costs.

Systematic review on molecular detection of congenital and neonatal infections caused by TORCH and SARS-CoV-2 in newborns' cerebrospinal fluid

OBJECTIVE

To verify the use and identify advantages of molecular methods for congenital infections diagnosis in cerebrospinal fluid of neonates.

DATA SOURCE

The review was registered in the International Prospective Register of Systematic Reviews (PROSPERO), under CRD42021274210. The literature search was performed in databases: PubMed, Virtual Health Library/ Latin American and Caribbean Center on Health Sciences Information (VHL/BIREME), Scopus, Web of Science, Excerpta Medica database (EMBASE), Cochrane, ProQuest, and EBSCOhost. The search was carried out from August to October 2021 and updated in December 2022, respecting the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The selection sequence was: 1) Duplicate title removal; 2) Examination of titles and abstracts; 3) Full-text retrieval of potentially relevant reports; and 4) Evaluation of the full text according to eligibility criteria by two independent authors. Inclusion criteria considered randomized and non-randomized control trials, longitudinal, cross-sectional, and peer-reviewed studies in humans, published in English, Spanish, Italian, and Portuguese, with newborns up to 28 days old who had congenital neuroinfections by toxoplasmosis, rubella, cytomegalovirus, herpes simplex (TORCH), and others such as Treponema pallidum, Zika, parvovirus B-19, varicella zoster, Epstein-Barr, and SARS-CoV2, diagnosed by polymerase chain reaction (PCR). Two evaluators extracted the following information: author, year of publication, nationality, subjects, study type, methods, results, and conclusion.

DATA SYNTHESIS

The most studied pathogen was herpes simplex. Several articles reported only nonspecific initial symptoms, motivating the collection of cerebrospinal fluid and performing PCR for etiological investigation.

CONCLUSIONS

Molecular methods are effective to detect pathogen genomes in cerebrospinal fluid, which can impact clinical evolution and neurological prognosis.

Neonatal herpes simplex virus infection: From the maternal infection to the child outcome

This review examines the recent literature on the management of herpes simplex virus (HSV) infections in neonates. We summarized the three clinical categories of maternal HSV infection during pregnancy (primary first episode, nonprimary first episode, or recurrent episode) and the mechanisms of fetal damage. Considering when the transmission of the infection from the mother to the fetus/newborn occurs, three types of neonatal infection can be distinguished: intrauterine infection (5% of cases), postnatal infection (10% of cases), and perinatal infections (85% of cases). Neonatal presentation could range from a limited disease with skin, eye, and mouth disease to central nervous system disease or disseminated disease: the treatment with acyclovir should be tailored according to symptoms and signs of infection, and virological tests. These children need a multidisciplinary follow-up, to timely intercept any deviation from normal neurodevelopmental milestones. Prevention strategies remain a challenge, in the absence of an available vaccine against HSV.

Diagnosis of Herpes Simplex Virus: Laboratory and Point-of-Care Techniques

Herpes is a widespread viral infection caused by the herpes simplex virus (HSV) that has no permanent cure to date. There are two subtypes, HSV-1 and HSV-2, that are known to cause a variety of symptoms, ranging from acute to chronic. HSV is highly contagious and can be transmitted via any type of physical contact. Additionally, viral shedding can also happen from asymptomatic infections. Thus, early and accurate detection of HSV is needed to prevent the transmission of this infection. Herpes can be diagnosed in two ways, by either detecting the presence of the virus in lesions or the antibodies in the blood. Different detection techniques are available based on both laboratory and point of care (POC) devices. Laboratory techniques include different biochemical assays, microscopy, and nucleic acid amplification. In contrast, POC techniques include microfluidics-based tests that enable on-spot testing. Here, we aim to review the different diagnostic techniques, both laboratory-based and POC, their limits of detection, sensitivity, and specificity, as well as their advantages and disadvantages.

Neonatal Herpes Simplex Virus Disease: Updates and Continued Challenges

This article defines neonatal herpes simplex virus (HSV) disease and describes the progress over the past 40 years that has revolutionized the management of HSV disease in neonates to improve their outcomes. These advancements include the introduction of acyclovir in the 1980s, polymerase chain reaction (PCR) for the detection of HSV DNA in the 1990s, and recommendations on managing infants born to mothers with active genital lesions. Despite these advancements, however, there remain high morbidity and mortality in affected neonates, with need for continued improvement. Areas of high interest include vaccine development and rapid PCR detection at time of delivery.

Antiviral Approaches for the Treatment of Herpes Simplex Virus Infections in Newborn Infants

Herpes simplex virus (HSV) infections in newborns are associated with severe disease and death. Trials conducted by the Collaborative Antiviral Study Group have established the standard of care for the treatment of neonatal HSV disease with marked improvements in morbidity and mortality. We review the studies that have contributed to our understanding of the epidemiology and clinical course of neonatal HSV disease and discuss the landmark trials that have resulted in safe and effective treatment together with improved diagnostics. Although significant advances have been made, neonatal HSV disease continues to have an unacceptably high mortality rate with significant sequelae in survivors. Further research is urgently needed for prevention.

Congenital and perinatal infections

Congenital and perinatal infections represent major causes of permanent disability among children worldwide. Linked together by the acronym TORCH, denoting Toxoplasma gondii, rubella virus, cytomegalovirus, and herpes virus, congenital infections can result from only a modest number of human pathogens that cross the placenta and infect the fetus. Although congenital rubella syndrome has been eliminated in the Americas by immunization, several pathogens discussed in this chapter cannot currently be prevented by vaccines or effectively treated with the available antimicrobial drugs. Due to the immaturity of the immune system, newborn infants are at risk for postnatally acquired infections with certain viruses and several bacteria. This chapter summarizes the epidemiology, pathogenesis, clinical manifestations, diagnosis, treatment, and prevention of selected pathogens that can damage the developing nervous system. As emphasized by the persisting challenges of preventing congenital cytomegalovirus infection and the emergence of severe brain damage associated with congenital Zika syndrome, these pathogens remain important causes of cerebral palsy, epilepsy, and intellectual disability.

The Tail Wagging the Dog (or the Challenges Faced When the Financing of Medicine Gets Ahead of the Science of Medicine)

In their article in this issue of the Journal of Clinical Microbiology, S. R. Dominguez et al. (J Clin Microbiol 56:e00632-18, 2018, https://doi.org/10.1128/JCM.00632-18) describe the performance of PCR detection of herpes simplex virus (HSV) DNA versus viral culture in skin and mucosal samples from 7 neonates with HSV disease. This is a significant contribution to our understanding of the optimal diagnostic approach in babies being evaluated for neonatal HSV disease. Many diagnostic laboratories already have made the change to molecular diagnostics for skin and mucosal swab testing, however, in large part due to the labor costs associated with viral cultures. Thus, important studies such as this one are being conducted to support a decision that has already been made in many locations on mostly economic grounds. This small case series supports the decision to use molecular testing for samples from skin and mucosal sites, but larger studies are needed to more fully define the performance characteristics of PCR in this population. Since a false-positive result would commit a baby to months of management that would be unnecessary and have potential harm, it is critical to base diagnostic decision making on data that support the use of a specific test.

Neonatal herpes simplex virus infections

Neonatal herpes simplex virus (HSV) is an uncommon but devastating infection in the newborn, associated with significant morbidity and mortality. The use of PCR for identification of infected infants and acyclovir for treatment has significantly improved the prognosis for affected infants. The subsequent use of suppressive therapy with oral acyclovir following completion of parenteral treatment of acute disease has further enhanced the long-term prognosis for these infants. This review article will discuss the epidemiology, risk factors and routes of acquisition, clinical presentation, and evaluation of an infant suspected to have the infection, and treatment of proven neonatal HSV disease.

Molecular Microbiology

Background

Nucleic acid (NA) amplification techniques are now commonly used to diagnose and manage patients with infectious diseases. The growth in the number of Food and Drug Administration–approved test kits and analyte-specific reagents has facilitated the use of this technology in clinical laboratories. Technological advances in NA amplification techniques, automation, NA sequencing, and multiplex analysis have reinvigorated the field and created new opportunities for growth. Simple, sample-in, answer-out molecular test systems are now widely available that can be deployed in a variety of laboratory and clinical settings. Molecular microbiology remains the leading area in molecular pathology in terms of both the numbers of tests performed and clinical relevance. NA-based tests have reduced the dependency of the clinical microbiology laboratory on more traditional antigen detection and culture methods and created new opportunities for the laboratory to impact patient care.

Content

This chapter reviews NA testing as it applies to specific pathogens or infectious disease syndromes, with a focus on those diseases for which NA testing is now considered the standard of care and highlights the unique challenges and opportunities that these tests present for clinical laboratories.

[Genital herpes and pregnancy: Serological and molecular diagnostic tools. Guidelines for clinical practice from the French College of Gynecologists and Obstetricians (CNGOF)]

OBJECTIVES

To describe serological and molecular tools available for genital and neonatal herpes, and their use in different clinical situations.

METHODS

Bibliographic investigations from MedLine database and consultation of international clinical practice guidelines.

RESULTS

Virological confirmation of genital herpes during pregnancy or neonatal herpes must rely on PCR (Professional consensus). HSV type-specific serology (IgG) will allow determining the immune status of a patient (in the absence of clinical lesions). However, there is currently no evidence to justify universal HSV serological testing during pregnancy (Professional consensus). In case of genital lesions in a pregnant woman that do not report any genital herpes before, it is recommended to perform a virological confirmation by PCR and HSV type-specific IgG in order to distinguish a true primary infection, a non-primary infection associated with first genital manifestation, from a recurrence (Grade C). HSV IgM is useless for diagnosis of genital herpes (Grade C). If a pregnant woman has personal history of genital herpes but no lesions, whatever the gestational age, it is not recommended to perform genital sampling nor serology (Professional consensus). In case of recurrence, if the lesion is characteristic of herpes, virological confirmation is not necessary (Professional Agreement). However, if the lesion is not characteristic, virological confirmation by PCR should be performed (Professional consensus). At birth, HSV PCR samples should be collected as soon as neonatal herpes is suspected (symptomatic neonate) (best before beginning antiviral treatment but must not delay the treatment), or after 24hours of life in case of asymptomatic neonate born to a mother with herpes lesions at delivery (Professional consensus). Clinical samples for virological confirmation should include at least blood and a peripheral location. In case of clinical manifestations of herpes in the neonate, first samples PCR positive, preterm birth, or maternal primary infection or non-primary infection associated with first genital manifestation at delivery, CSF should also be collected as well as samples of lesions in the neonate if present (Professional consensus). Sampling should be repeated in case of PCR negative but strong evidence of neonatal herpes (Professional consensus). HSV serology is useless for diagnosis of neonatal herpes (Grade C).

CONCLUSIONS

Virological confirmation for diagnosis of genital herpes during pregnancy or neonatal herpes must rely on PCR. PCR assays available in France are very reliable. Specific IgG are dedicated to restricted indications.

[Neonatal herpes: Epidemiology, clinical manifestations and management. Guidelines for clinical practice from the French College of Gynecologists and Obstetricians (CNGOF)]

OBJECTIVES

To describe the epidemiology of neonatal herpes and its risk factors, clinical and paraclinic manifestations, propose guidelines for a newborn at risk of neonatal herpes, describe treatment modalities, describe post-natal transmission and its prevention.

METHODS

Bibliographic search from Medline, Cochrane Library databases and research of international clinical practice guidelines.

RESULTS

Neonatal herpes is rare (about 20 cases per year in France) and mainly due to HSV 1 (level of evidence LE3). The main risk factors for mother-to-child transmission are maternal primary episode of genital herpes close to delivery and serotype HSV 1 (LE3). There are three clinical forms of neonatal herpes : SEM infection for skin, eyes and mucosa, central nervous system (CNS) associated infection, and the disseminated infection. Neurological mortality and morbidity depend on the clinical form and the HSV serotype (LE3). In most of the case of neonatal herpes, the mothers have no history of genital herpes (LE3). Fever and vesicular rash may be absent at the time of diagnosis (LE3). In case of suspicion of neonatal herpes, different samples (blood and cerebrospinal fluid) for HSV PCR must be carried out to confirm the diagnosis (Professional consensus). Any newborn suspected of neonatal herpes should be treated with intravenous aciclovir (Grade A) prior to the results of HSV PCR (Professional consensus). In case of maternal genital herpes at delivery, the management of an asymptomatic newborn depends on the evaluation of the risk of transmission. In case of maternal reactivation (low risk of transmission), HSV PCR samples are taken at 24hours of life and the newborn must be follow closely until results. In the case of maternal primary episode or non-primary infection first episode (high risk of transmission), the samples are taken at 24hours of life and intravenous treatment with aciclovir is started (Professional consensus). The treatment of neonatal herpes is based on intravenous aciclovir (60mg/kg/day divided into 3 injections) (Grade C). The duration of the treatment depends on the clinical form (14 days for the SEM infection, 21 days for the other forms) (Professional consensus). A relay with aciclovir per os (300mg/m²/day) for 6 months is recommended to improve the neurological outcome and reduce the risk of reactivation (grade B). Post-natal transmission is mainly due to HSV 1. The rules for the prevention of post-natal transmission must be known by parents and family, but also by nursing staff (Professional consensus). Breastfeeding is not contraindicated in cases of maternal herpes, except if there is herpetic lesion on the nipple (Professional consensus). Parents of newborns at risk for neonatal herpes should receive information on the clinical signs to be monitored at home after hospital discharge (Professional consensus).

CONCLUSIONS

Neonatal herpes is a rare disease with a high morbidity and mortality. The management of a newborn at risk requires good coordination between the obstetric and pediatric teams and parent's information.

Herpes simplex encephalitis as a complication of neurosurgical procedures: report of 3 cases and review of the literature

BACKGROUND

Herpes simplex virus (HSV) is the most common identified cause of focal encephalitis worldwide. However, postoperative HSV encephalitis (HSVE) is a rare complication of neurosurgical procedures and a significant clinical challenge

METHOD

We describe 3 cases of postoperative HSVE and review all published reports. A total of 23 cases were identified.

DISCUSSION

Clinical heterogeneity represents a diagnostic challenge in the postoperative setting. Cerebral magnetic resonance imaging showed typical findings in a minority of patients only, whereas HSV-specific polymerase chain reaction on the cerebrospinal fluid proved to be a valuable test. The postoperative viral pathophysiology remains a subject of debate. The rate of adverse outcome is high and early antiviral treatment seems to be a strong predictor of clinical outcome.

CONCLUSION

We recommend early empirical treatment for any patient presenting with post-neurosurgical lymphocytic meningo-encephalitis, and prophylactic antiviral treatment for patients with a history of previous HSVE who will undergo a neurosurgical procedure.

Herpes Simplex Virus DNAemia Preceding Neonatal Disease

Polymerase chain reaction testing of blood for herpes simplex virus (HSV) is recommended for newborns delivered to mothers with active genital HSV lesions at delivery. We report an infant who had a positive blood HSV polymerase chain reaction test before the onset of clinical signs of HSV disease.

Diffusion-weighted MRI for early diagnosis of neonatal herpes simplex encephalitis

AIM

To determine the early changes and evolutions of brain diffusion-weighted imaging (DWI), and analyze prognostic factors of the early changes among patients with neonatal herpes simplex encephalitis (NHSE).

METHOD

We selected patients who developed encephalitis by 28 d after birth; had herpes simplex infection; and who underwent magnetic resonance imaging, including DWI, ⩽7 d of symptom onset. Thirty-two DWI scans between 0 and 28 d after onset in 13 patients and the clinical data were recruited. The distribution, evolution of the lesions, and neurological outcome were analyzed.

RESULTS

DWI frequently showed multiple cortical lesions in both hemispheres in the early period and both hemispheres on DWI (8/9 scans at ⩽48 h, 7/7 patients). As time from onset increased, the cortical lesions tended to coincide with subcortical white matter lesions beneath the initial cortical lesions (p<0.01). Lesions from the cortex extended to the subcortical white matter in 7 patients. Deep cerebral lesions, involving basal ganglia, internal capsules, thalamus, were also found in 9 patients ⩽7 d of onset. The distributions of deep cerebral lesions (none/unilateral/bilateral) ⩽7 d of onset showed significant correlations with neurological prognoses (gross motor functions: p<0.01; developmental or intellectual quotient scores: p<0.01).

INTERPRETATION

Cortical lesions were main findings of DWI in NHSE in the early period. Bilateral deep cerebral lesions ⩽7 d were highly indicative of poor motor and cognitive outcomes.

Plasma and cerebrospinal fluid herpes simplex virus levels at diagnosis and outcome of neonatal infection

OBJECTIVE

To evaluate the utility of quantitative herpes simplex virus (HSV) polymerase chain reaction (PCR) levels for prognosis and management of neonatal HSV disease.

STUDY DESIGN

Clinical and virologic data were abstracted by medical record review from neonatal HSV cases treated at Seattle Children's Hospital between 1993 and 2012. HSV PCR results from plasma (n = 47), cerebrospinal fluid (n = 56), or both (n = 40) at the time of diagnosis were available from 63 infants; 26 with skin-eye-mouth (SEM), 18 with central nervous system (CNS), and 19 with disseminated (DIS) disease.

RESULTS

Plasma HSV PCR was positive in 78% of the infants with SEM, 64% with CNS and 100% with DIS disease. Mean plasma viral level was 2.8 log10 copies/mL in SEM, 2.2 log10 copies/mL in CNS, and 7.2 log10 copies/mL in DIS infants. The HSV levels were higher among infants who died compared with surviving infants, 8.1 log10 copies/mL (range 7.7-8.6) vs 3.8 log10 copies/mL (range 0.0-8.6), P = .001, however, level of HSV DNA in the cerebrospinal fluid or in plasma did not correlate with neurologic outcome. Dynamics of HSV clearance from plasma during high-dose acyclovir treatment showed single-phase exponential decay with a median viral half-life of 1.26 days (range: 0.8-1.51).

CONCLUSIONS

Plasma HSV levels correlate with clinical presentation of neonatal HSV disease and mortality, but not neurologic outcome.

Preventing herpes simplex virus in the newborn

Genital herpes simplex virus (HSV) infections are very common worldwide. Approximately 22% of pregnant women are infected genitally with HSV, and most of them are unaware of this. The most devastating consequence of maternal genital herpes is HSV disease in the newborn. Although neonatal HSV infections remain uncommon, due to the significant morbidity and mortality associated with the infection, HSV infection in the newborn is often considered in the differential diagnosis of ill neonates. This review summarizes the epidemiology and management of neonatal HSV infections and discusses strategies to prevent HSV infection in the newborn.

Early-onset neonatal sepsis

Early-onset sepsis remains a common and serious problem for neonates, especially preterm infants. Group B streptococcus (GBS) is the most common etiologic agent, while Escherichia coli is the most common cause of mortality. Current efforts toward maternal intrapartum antimicrobial prophylaxis have significantly reduced the rates of GBS disease but have been associated with increased rates of Gram-negative infections, especially among very-low-birth-weight infants. The diagnosis of neonatal sepsis is based on a combination of clinical presentation; the use of nonspecific markers, including C-reactive protein and procalcitonin (where available); blood cultures; and the use of molecular methods, including PCR. Cytokines, including interleukin 6 (IL-6), interleukin 8 (IL-8), gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α), and cell surface antigens, including soluble intercellular adhesion molecule (sICAM) and CD64, are also being increasingly examined for use as nonspecific screening measures for neonatal sepsis. Viruses, in particular enteroviruses, parechoviruses, and herpes simplex virus (HSV), should be considered in the differential diagnosis. Empirical treatment should be based on local patterns of antimicrobial resistance but typically consists of the use of ampicillin and gentamicin, or ampicillin and cefotaxime if meningitis is suspected, until the etiologic agent has been identified. Current research is focused primarily on development of vaccines against GBS.

Management of neonatal herpes simplex virus infection and exposure

Neonatal herpes simplex virus (HSV) infections are rare but are associated with significant morbidity and mortality. Advances in diagnostic modalities to identify these infants, as well as the development of safe and effective antiviral therapy, have revolutionised the management of affected infants. This review will summarise the epidemiology of neonatal HSV infections and discuss the management of infants with HSV exposure and infection.

Herpes simplex virus infection in neonates and young infants with sepsis

BACKGROUND

Neonatal herpes infection is the most serious complication of Herpes Simplex Virus (HSV) infection during pregnancy and perinatal period. Few studies have reported neonatal HSV infection in developing countries.

OBJECTIVES

The aim of this study was to detect the HSV infection among neonates and infants with sepsis.

MATERIALS AND METHODS

In a cross sectional study all infants aged less than 3 months, admitted to neonatal intensive care unit and pediatric emergency ward of Ghaem Hospital (a university hospital with 900 beds) in Mashhad (Northeast of Iran) with clinical diagnosis of sepsis and at least one inclusion criteria during one year from November 2009 to October 2010, were enrolled in the study. Polymerase chain reaction (PCR) was done on clinical samples obtained from patients.

RESULTS

Among 150 neonates and infants younger than 3 months old with sepsis, the PCR results for detecting the HSV DNA, were positive in 6 samples of 5 patients (3.3 %). None of the mothers had symptomatic HSV infection during delivery. The mean age of the patients was 18 days. Two of them died due to shock and disseminated intravascular coagulation (DIC).

CONCLUSIONS

In neonates and infants with primary diagnosis of sepsis, HSV infection should be considered especially if the clinical condition does not improve after 48 hours of antibiotic therapy, and sepsis still exists with elevated liver enzymes.

Fever in the pediatric patient

Fever is the most common reason that children and infants are brought to emergency departments. Emergency physicians face the challenge of quickly distinguishing benign from life-threatening conditions. The management of fever in children is guided by the patient's age, immunization status, and immune status as well as the results of a careful physical examination and appropriate laboratory tests and radiographic views. In this article, the evaluation and treatment of children with fevers of known and unknown origin are described. Causes of common and dangerous conditions that include fever in their manifestation are also discussed.

Neonatal herpes simplex virus infections

Neonatal herpes simplex virus infections are uncommon, but because of the morbidity and mortality associated with the infection they are often considered in the differential diagnosis of ill neonates. The use of polymerase chain reaction for diagnosis of central nervous system infections and the development of safe and effective antiviral therapy has revolutionized the diagnosis and management of these infants. Initiation of long-term antiviral suppressive therapy in these infants has led to significant improvement in morbidity. This article summarizes the epidemiology of neonatal herpes simplex virus infections and discusses clinical presentation, diagnosis, management, and follow up of infants with neonatal herpes disease.

Guidance on management of asymptomatic neonates born to women with active genital herpes lesions

Herpes simplex virus (HSV) infection of the neonate is uncommon, but genital herpes infections in adults are very common. Thus, although treating an infant with neonatal herpes is a relatively rare occurrence, managing infants potentially exposed to HSV at the time of delivery occurs more frequently. The risk of transmitting HSV to an infant during delivery is determined in part by the mother's previous immunity to HSV. Women with primary genital HSV infections who are shedding HSV at delivery are 10 to 30 times more likely to transmit the virus to their newborn infants than are women with recurrent HSV infection who are shedding virus at delivery. With the availability of commercial serological tests that reliably can distinguish type-specific HSV antibodies, it is now possible to determine the type of maternal infection and, thus, further refine management of infants delivered to women who have active genital HSV lesions. The management algorithm presented herein uses both serological and virological studies to determine the risk of HSV transmission to the neonate who is delivered to a mother with active herpetic genital lesions and tailors management accordingly. The algorithm does not address the approach to asymptomatic neonates delivered to women with a history of genital herpes but no active lesions at delivery.

Pathogenesis of neonatal herpes simplex 2 disease in a mouse model is dependent on entry receptor expression and route of inoculation

Herpes simplex virus (HSV) pathogenesis in mice differs based on availability of the principal entry receptors herpesvirus entry mediator (HVEM) and nectin-1 in a manner dependent upon route of inoculation. After intravaginal or intracranial inoculation of adult mice, nectin-1 is a major mediator of neurologic disease, while the absence of either receptor attenuates disease after ocular infection. We tested the importance of receptor availability and route of infection on disease in mouse models of neonatal HSV. We infected 7-day-old mice lacking neither or one principal HSV receptor or both principal HSV receptors with HSV-2 via a peripheral route (intranasal), via a systemic route (intraperitoneal), or by inoculation directly into the central nervous system (intracranial). Mortality, neurologic disease, and visceral dissemination of virus were significantly attenuated in nectin-1 knockout mice compared with HVEM knockout or wild-type mice after intranasal inoculation. Mice lacking both entry receptors (double-knockout mice) showed no evidence of disease after inoculation by any route. Nectin-1 knockout mice had delayed mortality after intraperitoneal inoculation relative to wild-type and HVEM knockout mice, but virus was able to spread to the brain and viscera in all genotypes except double-knockout mice. Unlike in adult mice, HVEM was sufficient to mediate disease in neonatal mice after direct intracranial inoculation, and the absence of HVEM delayed time to mortality relative to that of wild-type mice. Additionally, in wild-type neonatal mice inoculated intracranially, HSV antigen did not primarily colocalize with NeuN-positive neurons. Our results suggest that differences in receptor expression between adults and newborns may partially explain differences in susceptibility to HSV-2.

Diagnostics for Herpes Simplex Virus

Herpes simplex virus (HSV) is one of the most common, yet frequently overlooked, sexually transmitted infections. Since the type of HSV infection affects prognosis and subsequent counseling, type-specific testing to distinguish HSV-1 from HSV-2 is recommended. Although PCR has been the diagnostic standard for HSV infections of the central nervous system, until now viral culture has been the test of choice for HSV genital infection. However, HSV PCR, with its consistently and substantially higher rate of HSV detection, will likely replace viral culture as the gold standard for the diagnosis of genital herpes in people with active mucocutaneous lesions, regardless of anatomic location or viral type. Alternatively, type-specific serologic tests based on glycoprotein G should be the test of choice to establish the diagnosis of HSV infection when no active lesion is present. Given the difficulty in making the clinical diagnosis of HSV, the growing worldwide prevalence of genital herpes and the availability of effective antiviral therapy, there is an increased demand for rapid, accurate laboratory diagnosis of patients with HSV.

Use of blood polymerase chain reaction testing for diagnosis of herpes simplex virus infection

The use of herpes simplex virus (HSV) polymerase chain reaction for diagnosis of HSV disease involving the central nervous system has not translated into widespread use for the detection of DNAemia. We report our 6-year experience using blood polymerase chain reaction testing for HSV infection in neonates and older children with HSV disease.

Herpes simplex virus 2 infection rate and necessity of screening during pregnancy: a clinical and seroepidemiologic study

PURPOSE

This study determined the seroprevalence of herpes virus 2 in gravidas and the differences between herpes virus 2-infected and healthy gravidas. The need to screen gravidas for herpes virus 2 was also evaluated.

MATERIALS AND METHODS

A retrospective analysis involving 500 gravidas who underwent herpes virus 2 serologic testing and delivery in our hospital between January 2009 and August 2010 was performed. All patients in the study group were classified as herpes simplex virus 2 (HSV2) positive, and all cases were analyzed with respect to the clinical course of the pregnancy, pregnancy outcome, obstetric complications, and neonatal outcomes. SPSS software (version 14.0) was used for statistical analysis. A chi-square test and Student's t-test were used for statistical analysis.

RESULTS

In the current study, the herpes virus 2 seroprevalence rate in gravidas was 17%. There was no significant difference in the rates of preterm delivery, premature rupture of membranes, preterm labor, and intrauterine growth restriction between the herpes virus 2-infected gravidas and the healthy control group. The rates of spontaneous abortion and sexually transmitted disease were higher in the herpes virus 2 infection group than the healthy control group.

CONCLUSION

After educating gravidas on genital herpes and, if gravidas thereafter consent to herpes virus 2 screening, the risk of neonatal herpes virus 2 infections can be reduced. In addition, examination of gravidas for sexually transmitted diseases would increase as would appropriate treatment.

Population-based surveillance for neonatal herpes in New York City, April 2006-September 2010

BACKGROUND

Population-based data for neonatal herpes simplex virus (HSV) infection are needed to describe disease burden and to develop and evaluate prevention strategies.

METHODS

From April 2006 to September 2010, routine population-based surveillance was conducted using mandated provider and laboratory reports of neonatal HSV diagnoses and test results for New York City resident infants aged ≤60 days. Case investigations, including provider interviews and review of infant and maternal medical charts and vital records, were performed. Hospital discharge data were analyzed and compared with surveillance data findings.

RESULTS

Between April 2006 and September 2010, New York City neonatal HSV surveillance detected 76 cases, for an average incidence of 13.3/100,000 (1/7519) live births. Median annual incidence of neonatal HSV estimated from administrative data for 1997 to 2008 was 11.8/100,000. Among surveillance cases, 90.8% (69/76) were laboratory confirmed. Among these, 40.6% (28/69) were HSV-1; 39.1% (27/69) were HSV-2; and 20.3% (14/69) were untyped. The overall case-fatality rate was 17.1% (13/76). Five cases were detected among infants aged >42 days. In all, 80% (20/25) of the case-infants delivered by cesarean section were known to have obstetric interventions that could have increased risk of neonatal HSV transmission to the infant before delivery. Over half (68%, or 52/76) of all cases lacked timely or ideal diagnostics or treatment.

CONCLUSIONS

Administrative data may be an adequate and relatively inexpensive source for assessing neonatal HSV burden, although they lack the detail and timeliness of surveillance. Prevention strategies should address HSV-1. Incubation periods might be longer than expected for neonatal HSV. Cesarean delivery might not be protective if preceded by invasive procedures. Provider education is needed to raise awareness of neonatal HSV and to assure appropriate testing and treatment.

Congenital and perinatal infections: throwing new light with an old TORCH

Infections acquired in utero or in the immediate post-natal period play a prominent role in perinatal and childhood morbidity. The TORCH constellation continues to be popular among perinatologists and paediatricians, although its limitations are increasingly known. A host of new organisms are now considered to be perpetrators of congenital and perinatal infections, and a diverse range of diagnostic tests are now available for confirming infection in the infant. In general, the collective TORCH serological panel has low diagnostic yield; instead individual tests ordered according to clinical presentation can contribute better towards appropriate diagnosis. This review captures the essence of established congenital infections such as cytomegalovirus, rubella, toxoplasmosis, syphilis and herpes simplex virus, as well as more recent entrants such as HIV and hepatitis B infection, varicella and tuberculosis. Selective screening of the mother and newborn, encouraging good personal hygiene and universal immunization are some measures that can contribute towards decreasing the incidence and morbidity of congenital and perinatal infections.

Neonatal herpes simplex virus infections: where are we now?

Neonatal herpes simplex virus (HSV) infection continues to cause significant morbidity and mortality despite advances in diagnosis and treatment. Prior to antiviral therapy, 85% of patients with disseminated HSV disease and 50% of patients with central nervous system disease died within 1 year. The advent of antiviral therapy has dramatically improved the prognosis of neonatal HSV with initially vidarabine and subsequently acyclovir increasing the survival rate of infected neonates and improving long-term developmental outcomes. More recently, polymerase chain reaction has allowed earlier identification of HSV infection and provided a quantitative guide to treatment. Current advances in the treatment of neonatal HSV infections are looking toward the role of prolonged oral suppression therapy in reducing the incidence of recurrent disease. Of concern, however, are increasing reports of acyclovir-resistant HSV isolates in patients following prolonged therapy.

[Experience with multiplex nested PCR and fluorescent antibody tests in the diagnosis of acute central nervous system infections with herpes simplex virus type 1 and 2]

The specific diagnosis of herpes simplex virus type 1 and 2 infections has an extreme importance in acute infections of central nervous system due to both availability of specific antiviral therapy and the possible serious consequences of the disease.

AIMS

Evaluation of the relevance and interpretation of the results of PCR and the specific antibody testing.

METHODS

Home made multiplex nested herpes simplex virus PCR and immunofluorescent IgM, IgA, IgG antibody tests were carried out in a total of 474 cerebrospinal fluid and 555 serum samples of 396 patients with acute infection of the central nervous system between 1. January, 2003 and 31. December, 2009.

RESULTS

The herpes simplex virus etiology was verified in 21% of 396 patients (82 patients, mean 12 cases per year): 26 were diagnosed by both methods (32%), 41 by PCR only (50%), 15 by the detection of intrathecal antibody production only (18%) (p<0.0001). HSV type1 or 2 DNA remained detectable in 35% of the samples drawn after the 30th day of the disease. These patients were all younger than two years of age.

CONCLUSIONS

1. PCR increased the ratio of verified herpes simplex virus etiology in acute central nervous infections. 2. Testing the specific antibody response cannot be ceased even in the availability of PCR. 3. Herpes simplex virus type 1 or 2 DNA might persist in central nervous system in spite of the specific antiviral therapy especially in the infants. 4. Herpes simplex virus PCR can be repeated if an early sample is negative or if it is suspected false positive. 5. There is a need for cooperation between clinicians and virologists in the appropriate interpretation of the results and in finding etiology.

Neonatal herpes simplex virus infection

Herpes simplex virus (HSV) infection in the neonate is a rare event with severe consequences for the child even if adequately treated with antiviral drugs. Mothers with primary genital herpes infections late in pregnancy or at delivery have a high risk of transferring the infection to the child, while the risk of transfer in mothers with recurrent genital infections is only a few percent. Neonatal herpes localized in skin-eye-mouth has no mortality and morbidity after antiviral treatment. In neonatal disseminated and central nervous system disease, early treatment is a predictor for better outcome. The morbidity in survivors is high; after herpes encephalitis, only one-third of children have normal development. While awaiting vaccines or reliable predictors for prevention of neonatal herpes, clinical awareness of primary maternal herpes during pregnancy and recommendations for prophylactic treatment are important tools. For pediatricians the differential diagnosis of a child aged two to four weeks with seizures, neonatal herpes encephalitis must be considered and either excluded or treated. Neurological follow-up and training programs to minimize the consequences of a disability are important clinical aspects.

A double-blind placebo-controlled study to evaluate valacyclovir alone and with aspirin for asymptomatic HSV-1 DNA shedding in human tears and saliva

PURPOSE

To test the effect of valacyclovir alone and with aspirin on the asymptomatic shedding of HSV-1 DNA in tears and saliva of healthy individuals. METHOD. The subjects (n = 45) were randomized into three groups without regard to age, sex, or race. Group 1 (n = 14) received the placebo, group 2 (n = 15) received a dose of 500 mg valacyclovir once daily, and group 3 (n = 16) received a dose of 500 mg valacyclovir once daily and 350 mg aspirin twice daily for 30 days. Ocular and oral swabs were collected twice daily for 30 days. DNA was extracted from all swabs and HSV-1 DNA copy numbers were determined. Statistical analysis was performed to compare the DNA copy numbers of the three groups.

RESULTS

There was no significant difference in the HSV-1 DNA copy numbers in the tears or saliva among any of the three treatment groups. The mean copy numbers +/- SE of mean (SEM) of HSV-1 DNA in tears were 340 +/- 35, 1074 +/- 320, and 630 +/- 51 for groups 1, 2, and 3, and in saliva were 238 +/- 35, 963 +/- 462, and 493 +/- 25, respectively, for groups 1, 2, and 3.

CONCLUSIONS

No correlation was found between HSV-1 shedding and valacyclovir and valacyclovir with aspirin treatment. The HSV-1 DNA copy number was not reduced by treatment with 500 mg of valacyclovir daily or with a combination of daily valacyclovir (500 mg) plus twice-daily doses of aspirin (350 mg) over 30 days.

Antiviral agents for treatment of herpes simplex virus infection in neonates

BACKGROUND

Herpes simplex virus (HSV) is a rare but serious neonatal pathogen. Prior to the availability of antiviral drugs the mortality associated with all but localised neonatal infection was high, with 85% of infants with disseminated HSV infection and 50% of infants with encephalitis dying by one year of age. The morbidity in the survivors of multiorgan infection was also high, with up to 50% experiencing long-term neurological sequelae.

OBJECTIVES

To determine the effect of antiviral agents in the treatment of neonatal HSV infections on mortality, progression of disease and neurodevelopmental sequelae at approximately one year. The secondary objective was to assess the effect of antiviral agents on major complications associated with the use of these agents including nephrotoxicity and bone marrow suppression.

SEARCH STRATEGY

Trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2008), MEDLINE (1996 - Nov 2008), EMBASE (1982 - Nov 2008) and reference lists of published trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of antiviral therapy in infants less than one month of age with virologically proven HSV infection were included.

DATA COLLECTION AND ANALYSIS

Data were extracted and the analyses performed independently by two review authors. Studies were analysed for methodological quality using the criteria of the Cochrane Neonatal Review Group. All data were analysed using RevMan 5.1. When possible, meta-analysis was performed to calculate typical relative risk, typical risk difference, along with their 95% confidence intervals (CI).

MAIN RESULTS

Two eligible studies of a total of 273 infants were included. Both studies were randomized controlled trials. One study treated 63 infants with vidarabine or placebo (Whitley 1980) and the other study treated 210 infants with aciclovir or vidarabine (Whitley 1991).In the study comparing vidarabine with placebo (Whitley 1980), infants with all forms of neonatal HSV disease were included [disseminated disease, central nervous system (CNS) disease alone, and skin, eye and mouth (SEM) disease].There was no significant reduction in the risk of mortality when analyzed as an entire group; however, mortality was significantly reduced when data from infants with CNS disease or disseminated disease were combined. There was no difference in the rate of neurological abnormalities in survivors at one year when analyzed as an entire group or by disease category.There was no difference between aciclovir and vidarabine (Whitley 1991) in preventing mortality from neonatal HSV disease, in preventing disease progression, in reducing the incidence of neurological abnormality at one year, or in the incidence of drug-induced renal or bone marrow toxicity. In infants with SEM disease, there was no significant difference in neurological outcome with aciclovir compared vidarabine treatment. Both drugs were well tolerated in the newborn period.

AUTHORS' CONCLUSIONS

There is insufficient trial evidence to evaluate the effects of antiviral agents with controls or with each other. The rarity of the condition makes effectively powered clinical trials difficult to perform. The efficacy of newer antiviral agents with better bioavailability (e.g. valaciclovir, valganciclovir) for the treatment of neonatal disease needs to be evaluated in randomised trials. The efficacy of oral formulations need to be evaluated as they may be useful for infants with skin, eye or mouth HSV disease or in the treatment of infants with recurrences after the neonatal period.

Antiviral agents for treatment of herpes simplex virus infection in neonates

BACKGROUND

Herpes simplex virus (HSV) is a rare but serious neonatal pathogen. Prior to the availability of antiviral drugs the mortality associated with all but localised neonatal infection was high, with 85% of infants with disseminated HSV infection and 50% of infants with encephalitis dying by one year of age. The morbidity in the survivors of multiorgan infection was also high, with up to 50% experiencing long-term neurological sequelae.

OBJECTIVES

To determine the effect of antiviral agents in the treatment of neonatal HSV infections on mortality, progression of disease and neurodevelopmental sequelae at approximately one year. The secondary objective was to assess the effect of antiviral agents on major complications associated with the use of these agents including nephrotoxicity and bone marrow suppression.

SEARCH STRATEGY

Trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 4, 2008), MEDLINE (1996 - Nov 2008), EMBASE (1982 - Nov 2008) and reference lists of published trials.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials of antiviral therapy in infants less than one month of age with virologically proven HSV infection were included.

DATA COLLECTION AND ANALYSIS

Data were extracted and the analyses performed independently by two review authors. Studies were analysed for methodological quality using the criteria of the Cochrane Neonatal Review Group. All data were analysed using RevMan 5.1. When possible, meta-analysis was performed to calculate typical relative risk, typical risk difference, along with their 95% confidence intervals (CI).

MAIN RESULTS

Two eligible studies of a total of 273 infants were included. Both studies were randomized controlled trials. One study treated 63 infants with vidarabine or placebo (Whitley 1980) and the other study treated 210 infants with aciclovir or vidarabine (Whitley 1991).In the study comparing vidarabine with placebo (Whitley 1980), infants with all forms of neonatal HSV disease were included [disseminated disease, central nervous system (CNS) disease alone, and skin, eye and mouth (SEM) disease].There was no significant reduction in the risk of mortality when analyzed as an entire group; however, mortality was significantly reduced when data from infants with CNS disease or disseminated disease were combined. There was no difference in the rate of neurological abnormalities in survivors at one year when analyzed as an entire group or by disease category.There was no difference between aciclovir and vidarabine (Whitley 1991) in preventing mortality from neonatal HSV disease, in preventing disease progression, in reducing the incidence of neurological abnormality at one year, or in the incidence of drug-induced renal or bone marrow toxicity. In infants with SEM disease, there was no significant difference in neurological outcome with aciclovir compared vidarabine treatment. Both drugs were well tolerated in the newborn period.

AUTHORS' CONCLUSIONS

There is insufficient trial evidence to evaluate the effects of antiviral agents with controls or with each other. The rarity of the condition makes effectively powered clinical trials difficult to perform. The efficacy of newer antiviral agents with better bioavailability (e.g. valaciclovir, valganciclovir) for the treatment of neonatal disease needs to be evaluated in randomised trials. The efficacy of oral formulations need to be evaluated as they may be useful for infants with skin, eye or mouth HSV disease or in the treatment of infants with recurrences after the neonatal period.

Persistence of herpes simplex virus DNA in cerebrospinal fluid of neonates with herpes simplex virus encephalitis

OBJECTIVE

The significance of detecting herpes simplex virus (HSV) DNA in the cerebrospinal fluid (CSF) of infants with HSV encephalitis after receipt of prolonged therapy with high-dose (60 mg kg(-1) day(-1)) acyclovir is unknown. We report the clinical and laboratory characteristics, neuroimaging studies and outcomes of four neonates with HSV encephalitis who had persistence of CSF HSV DNA, by polymerase chain reaction (PCR) after 15 to 21 days of high-dose acyclovir therapy.

STUDY DESIGN

Retrospective chart review.

RESULTS

All four infants had abnormal neuroimaging studies and subsequently experienced severe developmental delay or death.

CONCLUSION

A persistently positive CSF HSV PCR in neonates may be another risk factor for worse neurodevelopmental outcome. Prospective studies are needed to document how often HSV DNA persists in CSF, elucidate whether it represents an initially high CSF viral load, ongoing viral replication or viral resistance, and determine its possible association with neurodevelopmental impairment.

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.

Imaging findings of neonatal herpes simplex virus type 2 encephalitis

INTRODUCTION

The CT, MR, and diffusion-weighted initial and follow-up imaging findings in neonatal herpes simplex virus type 2 (HSV-2) encephalitis were assessed.

METHODS

The clinical, laboratory and imaging findings in 12 patients (eight girls and four boys) with proven neonatal HSV-2 encephalitis with follow-up were retrospectively reviewed. Patterns of brain involvement and distribution of lesions were studied and the contribution of diffusion-weighted imaging to the imaging diagnosis of this disease was explored. A total of 24 CT and 22 MRI studies were performed with a mean follow-up time of 38 months.

RESULTS

Neonatal HSV-2 encephalitis can be multifocal or limited to only the temporal lobes, brainstem, or cerebellum. The deep gray matter structures were involved in 57% of patients, and hemorrhage was seen in more than half of the patients. CT images were normal or showed mild abnormalities in the early stages of the disease. Conventional MR images may be normal in the early stages of the disease. Lesions were initially seen only by diffusion-weighted imaging in 20% of the patients and this modality showed a substantially more extensive disease distribution in an additional 50% of patients. In 40% of patients, watershed distribution ischemic changes were observed in addition to areas of presumed direct herpetic necrosis.

CONCLUSION

Neonatal HSV-2 encephalitis has a variable imaging appearance. Diffusion-weighted MRI is an important adjunct in the imaging evaluation of this disease. Watershed distribution ischemia in areas remote from the primary herpetic lesions may be seen.

Brainstem involvement in neonatal herpes simplex virus type 2 encephalitis

Herpes simplex virus encephalitis in the newborn typically involves the cerebral cortex in a widespread manner. Herpes simplex virus type 2 rarely involves the brainstem. Here we report a 16-day-old infant with predominant brainstem and cerebellar involvement secondary to herpes simplex virus type 2 infection. Diffusion-weighted MRI performed 3 days after the onset of symptoms revealed restricted diffusion mainly in brainstem and cerebellar structures. No abnormal findings were seen on conventional MRI. Subsequent MRI scans showed evolution of the brain injury with extension along the corticospinal tracts. However, there was no evidence of any other supratentorial gray or white matter injury. This is the first report of predominant brainstem involvement in neonatal herpes simplex virus type 2 encephalitis. In addition, the importance of performing diffusion-weighted sequences to detect early central nervous system involvement and serial MRI to follow the evolution of central nervous system lesions is emphasized.

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.