Herpes simplex virus DNA in amniotic fluid without neonatal infection

Disseminated herpes simplex virus 2 as a complication of pregnancy

Disseminated herpes simplex virus 2 (HSV-2) infection, is a rare but devastating infection in pregnancy women. We present the case of a 30-year-old gravida 3, para 2-0-0-2, at 26 weeks 2 days gestation who presented with eleven days of vague and indolent symptoms before a diagnosis of disseminated HSV-2 infection with associated hepatitis was made. While the patient clinically improved with empiric acyclovir treatment, possibility of significant harm to the fetus remained, and the patient request elective termination. The authors review the epidemiology, diagnosis, treatment, and prognosis of disseminated HSV-2 infection in pregnancy.

Infectious causes of microcephaly: epidemiology, pathogenesis, diagnosis, and management

Microcephaly is an important sign of neurological malformation and a predictor of future disability. The 2015-16 outbreak of Zika virus and congenital Zika infection brought the world's attention to links between Zika infection and microcephaly. However, Zika virus is only one of the infectious causes of microcephaly and, although the contexts in which they occur vary greatly, all are of concern. In this Review, we summarise important aspects of major congenital infections that can cause microcephaly, and describe the epidemiology, transmission, clinical features, pathogenesis, management, and long-term consequences of these infections. We include infections that cause substantial impairment: cytomegalovirus, herpes simplex virus, rubella virus, Toxoplasma gondii, and Zika virus. We highlight potential issues with classification of microcephaly and show how some infants affected by congenital infection might be missed or incorrectly diagnosed. Although Zika virus has brought the attention of the world to the problem of microcephaly, prevention of all infectious causes of microcephaly and appropriately managing its consequences remain important global public health priorities.

Herpes Simplex Virus and Varicella-Zoster Virus

The most common specimens from immunocompromised patients that are analyzed for detection of herpes simplex virus (HSV) or varicella-zoster virus (VZV) are from skin lesions. Many types of assays are applicable to these samples, but some, such as virus isolation and direct fluorescent antibody testing, are useful only in the early phases of the lesions. In contrast, nucleic acid (NA) detection methods, which generally have superior sensitivity and specificity, can be applied to skin lesions at any stage of progression. NA methods are also the best choice, and sometimes the only choice, for detecting HSV or VZV in blood, cerebrospinal fluid, aqueous or vitreous humor, and from mucosal surfaces. NA methods provide the best performance when reliability and speed (within 24 hours) are considered together. They readily distinguish the type of HSV detected or the source of VZV detected (wild type or vaccine strain). Nucleic acid detection methods are constantly being improved with respect to speed and ease of performance. Broader applications are under study, such as the use of quantitative results of viral load for prognosis and to assess the efficacy of antiviral therapy.

Asymptomatic Herpes Simplex Virus Infection in Iranian Mothers and Their Newborns

This study aims to determine the prevalence of herpes simplex virus (HSV) infection among pregnant women as well as congenital infection of their newborns in Tehran. One hundred samples of blood sera from pregnant women were analyzed for the presence of HSV specific antibodies. Umbilical cord blood samples from the newborns were analyzed for the presence of HSV DNA using real-time PCR. HSV IgG and IgM antibodies were found in 97% and 2% of pregnant women, respectively. Of all the 100 cord blood samples, 6 were positive for HSV DNA in which 2 cases were from mothers who had detectable IgM. It was notable that all corresponding mothers of six HSV positive infants had detectable IgG antibodies in their sera. It was demonstrated that the presence of HSV DNA in cord blood of newborns could be a risk marker for maternal-fetal transmission of the virus in asymptomatic pregnant women.

Viral invasion of the amniotic cavity (VIAC) in the midtrimester of pregnancy

INTRODUCTION

The prevalence of viral infections in the amniotic fluid (AF) has not yet been ascertained. The aim of this study was to determine the prevalence of specific viral nucleic acids in the AF and its relationship to pregnancy outcome.

STUDY DESIGN

From a cohort of 847 consecutive women undergoing midtrimester amniocentesis, 729 cases were included in this study after exclusion of documented fetal anomalies, chromosomal abnormalities, unavailability of AF specimens and clinical outcomes. AF specimens were tested by quantitative real-time PCR for the presence of genome sequences of the following viruses: adenoviruses, herpes simplex virus (HSV), varicella zoster virus (VZV), human herpesvirus 6 (HHV6), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), parvovirus B19 and enteroviruses. Viral nucleic acid testing was also performed in maternal blood and cord blood in the population of women in whom AF was positive for viruses and in a control group of 29 women with AF negative for viral nucleic acids. The relationship between the presence of viruses and pregnancy and neonatal outcome was examined. The correlation between the presence of nucleic acids of viruses in the AF and the concentration of the cytokine interleukin-6 (IL-6) and the T cell chemokine CXCL-10 (or IP-10) in AF and maternal blood were analyzed.

RESULTS

Viral genome sequences were found in 16 of 729 (2.2%) AF samples. HHV6 was the most commonly detected virus (7 cases, 1.0%), followed by HCMV (6 cases, 0.8%), parvovirus B19 (2 cases, 0.3%) and EBV (1 case, 0.1%), while HSV, VZV, enteroviruses and adenoviruses were not found in this cohort. Corresponding viral DNA was also detected in maternal blood of six out of seven women with HHV6-positive AF and in the umbilical cord plasma, which was available in one case. In contrast, viral DNA was not detected in maternal blood of women with AF positive for parvovirus B19, HCMV, EBV or of women with AF negative for viruses. HHV6 genome copy number in AF and maternal blood was consistent with genomic integration of viral DNA and genetic infection in all women. There was no significant difference in the AF concentration of IL-6 and IP-10 between patients with and without VIAC. However, for HCMV, there was a significant relationship between viral copy number and IP-10 concentration in maternal blood and AF. The group of women with AF positive for viral DNA delivered at term healthy neonates without complications in 14 out of 16 cases. In one case of HHV6 infection in the AF, the patient developed gestational hypertension at term, and in another case of HHV6 infection in the AF, the patient delivered at 33 weeks after preterm premature rupture of membranes (PPROM).

CONCLUSION

Viral nucleic acids are detectable in 2.2% of AF samples obtained from asymptomatic women in the midtrimester. HHV6 was the most frequently detected virus in AF. Adenoviruses were not detected. Vertical transmission of HHV6 was demonstrated in one case.

Quantitative Histological Examination of Bioprosthetic Heart Valves

BACKGROUND

The histological features that characterize infective endocarditis in bioprosthetic valves are not accurately defined. Moreover, bioprosthetic valves may have a noninfective, degenerative evolution associated with calcifications, vegetation-like lesions, and inflammatory infiltrates. Such histological findings may be misdiagnosed as infective endocarditis.

METHODS

Pathologic analysis of inflamed bioprosthetic valve tissues was conducted retrospectively for 21 patients who underwent surgical removal of a bioprosthetic valve because of suspected infective endocarditis and for 67 patients who underwent surgical removal of a bioprosthetic valve because of noninfective dysfunction. To better define the histological criteria for infective endocarditis, we used quantitative image analysis to compare these 2 groups of patients with respect to vegetations, calcifications, and patterns of inflammation.

RESULTS

Histologically, infective endocarditis in patients with bioprostheses was characterized by demonstration of microorganisms, vegetations, and neutrophil-rich, inflammatory infiltrates. Valve tissue specimens from patients whose bioprosthetic valves were removed because of noninfective complications showed, in 30% of cases, inflammatory infiltrates mainly composed of macrophages and lymphocytes. Inflammatory adherent thrombi that can occur to the surface of noninfective degenerative bioprostheses are differentiated because their vegetations have macrophage-rich content. A neutrophil surface area with a cutoff value of > or =1.5% of the total valve tissue surface area is highly specific (94%) for infective endocarditis.

CONCLUSIONS

When no microorganisms are detected and vegetations are not found in bioprosthetic valve tissues during the histological examination, a neutrophil-rich inflammation might better define the term "active endocarditis" in the Duke criteria and would allow differentiation between infective endocarditis and inflammatory, noninfective valve processes in patients with bioprosthetic valves.

Quantitative Histological Examination of Mechanical Heart Valves

BACKGROUND

Histological demonstration of microorganisms, vegetations, or active endocarditis in cardiac valve tissue is included in the Duke criteria and is considered to be a criterion of confirmed infective endocarditis. However, the histological features that characterize infective endocarditis are not accurately defined at the qualitative and quantitative levels.

METHODS

Pathologic analysis of tissue adjoining mechanical cardiac valves was undertaken retrospectively for 21 patients who underwent surgical removal of a mechanical valve because of suspected infective endocarditis and 69 patients who underwent surgical removal of a mechanical valve because of noninfectious dysfunction. To better define the histological criteria for infective endocarditis, we used quantitative image analysis to compare these 2 groups of patients with respect to valvular fibrosis, calcifications, vegetations, patterns of inflammation, and vascularization.

RESULTS

Histologically, infective endocarditis in patients with mechanical valves was characterized by the demonstration of microorganisms, vegetations, and significant neutrophil-rich inflammatory infiltrates with extensive neovascularization. In contrast, valve tissue specimens from patients with mechanical valves that were removed because of noninfectious complications showed significant rates of extensive fibrosis and, when present, inflammatory infiltrates that were mainly composed of macrophages and lymphocytes. A neutrophil surface area with a cutoff value of > or =2% of the total valve tissue surface is highly predictive of (90%) and specific for (98%) infective endocarditis.

CONCLUSIONS

When no microorganisms are detected and vegetations are lacking in tissue adjacent to a mechanical valve, neutrophil-rich inflammation and extensive neovascularization might better histologically define the term "active endocarditis" in the Duke criteria. This definition would allow differentiation between infective endocarditis and inflammatory noninfectious valve processes in patients with mechanical cardiac valves.

Diagnosis and treatment of herpes simplex infection during pregnancy

When pregnant women acquire primary herpes simplex genital infections or experience recurrent infections around the time of delivery, the risk of transmitting the disease to their newborns is significant. This perinatal transmission can result in a serious neonatal illness. Issues surrounding screening, treatment, and mode of delivery to prevent perinatal transmission often are confusing and controversial. Nurses delivering care to childbearing women and their newborns must be aware of the current information to give accurate and helpful information and support. Nurses also need to understand the effect this disease has both physiologically and psychosocially on women with primary infections, recurrent infections, and women at risk of acquiring the infection during pregnancy.