Perinatal infection with Listeria monocytogenes

Regulation of Placental Efflux Transporters during Pregnancy Complications

The placenta is essential for regulating the exchange of solutes between the maternal and fetal circulations. As a result, the placenta offers support and protection to the developing fetus by delivering crucial nutrients and removing waste and xenobiotics. ATP-binding cassette transporters, including multidrug resistance protein 1, multidrug resistance-associated proteins, and breast cancer resistance protein, remove chemicals through active efflux and are considered the primary transporters within the placental barrier. Altered transporter expression at the barrier could result in fetal exposure to chemicals and/or accumulation of xenobiotics within trophoblasts. Emerging data demonstrate that expression of these transporters is changed in women with pregnancy complications, suggesting potentially compromised integrity of placental barrier function. The purpose of this review is to summarize the regulation of placental efflux transporters during medical complications of pregnancy, including 1) placental inflammation/infection and chorioamnionitis, 2) hypertensive disorders of pregnancy, 3) metabolic disorders including gestational diabetes and obesity, and 4) fetal growth restriction/altered fetal size for gestational age. For each disorder, we review the basic pathophysiology and consider impacts on the expression and function of placental efflux transporters. Mechanisms of transporter dysregulation and implications for fetal drug and toxicant exposure are discussed. Understanding how transporters are up- or downregulated during pathology is important in assessing possible exposures of the fetus to potentially harmful chemicals in the environment as well as the disposition of novel therapeutics intended to treat placental and fetal diseases. SIGNIFICANCE STATEMENT: Diseases of pregnancy are associated with reduced expression of placental barrier transporters that may impact fetal pharmacotherapy and exposure to dietary and environmental toxicants.

An Update Review on Listeria Infection in Pregnancy

Listeria monocytogenes (LM) is an intracellular, aerobic and facultative anaerobic, Gram-positive bacterium, which is primarily transmitted to humans orally via food. LM could occur in asymptomatic pregnant women; however, fetal infection is a serious condition, entailing premature birth, abortion, sepsis, central nervous system (CNS) involvement, or even death. If a pregnant woman exhibits symptoms, the performance is almost like influenza, such as fever, headache, diarrhea, myalgia, or other digestive-related symptoms. This review collected clinical and empirical results regarding the mechanism, clinical manifestations, obstetrical outcome, diagnosis, treatment, vertical transmission, neonatal infection, and prevention of listeriosi according to articles published in PubMed from January 1, 1980, to March 20, 2021. The early detection and diagnosis of pregnancy-associated listeriosis are significant since sensitive antibiotics are effective at enhancing the prognosis of newborns. Listeriosis can be diagnosed using positive cultures from maternal or neonatal blood, neonatal cerebrospinal fluid (CSF), amniotic fluid, intrauterine mucosa, or the placenta. Two weeks of high-dose intravenous amoxicillin (more than 6 g/day) is recommended for LM pregnant women without allergy. Terminating the pregnancy to save the mother’s life should be considered if maternal and fetal conditions aggravate. Neonatal Listeria infection is primarily transmitted through the placenta, which is a critical illness associated with a high mortality rate. The necessary dietary guidance for pregnant women can reduce the incidence rate of pregnancy-related listeriosis.

Listeriosis Outbreak in South Africa: A Comparative Analysis with Previously Reported Cases Worldwide

Listeria species are Gram-positive, rod-shaped, facultative anaerobic bacteria, which do not produce endospores. The genus, Listeria, currently comprises 17 characterised species of which only two (L. monocytogenes and L. ivanovii) are known to be pathogenic to humans. Food products and related processing environments are commonly contaminated with pathogenic species. Outbreaks and sporadic cases of human infections resulted in considerable economic loss. South Africa witnessed the world's largest listeriosis outbreak, characterised by a progressive increase in cases of the disease from January 2017 to July 2018. Of the 1060 laboratory-confirmed cases of listeriosis reported by the National Institute of Communicable Diseases (NICD), 216 deaths were recorded. Epidemiological investigations indicated that ready-to-eat processed meat products from a food production facility contaminated with L. monocytogenes was responsible for the outbreak. Multilocus sequence typing (MLST) revealed that a large proportion (91%) of the isolates from patients were sequence type 6 (ST6). Recent studies revealed a recurrent occurrence of small outbreaks of listeriosis with more severe side-effects in humans. This review provides a comparative analysis of a recently reported and most severe outbreak of listeriosis in South Africa, with those previously encountered in other countries worldwide. The review focuses on the transmission of the pathogen, clinical symptoms of the disease and its pathogenicity. The review also focuses on the major outbreaks of listeriosis reported in different parts of the world, sources of contamination, morbidity, and mortality rates as well as cost implications. Based on data generated during the outbreak of the disease in South Africa, listeriosis was added to the South African list of mandatory notifiable medical conditions. Surveillance systems were strengthened in the South African food chain in order to assist in preventing and facilitating early detection of both sporadic cases and outbreaks of infections caused by these pathogens in humans.

Clinical study of fetal neurobehavior by the KANET test

Fetal neurology is evolving as an area of great interest in prenatal diagnosis and fetal medicine. The identification and diagnosis of brain damage prenatally has been a great challenge in obstetrics for many years. Investigations of fetal behavior in comparison with morphological studies led to the conclusion that fetal behavioral patterns directly reflect developmental and maturational processes of the fetal central nervous system (CNS). Four-dimensional (4D) ultrasound has greatly improved the assessment of the quality of the fetal spontaneous movements, and enabled a better evaluation of fetal behavior. The assessment of normal neurobehavioral development by 4D ultrasound provided the opportunity to investigate functional characteristics of the fetus that could predict neurological developmental dysfunction. Some studies have already been carried out to evaluate this new methodology in the observation of fetal behavior during different stages of gestation, in an attempt to better understand the relationships between the maturation of the CNS of the fetus and its implications on its behavior pattern. We present a review of literature on fetal behavior by 4D ultrasound.

Prevalence of early-onset neonatal infection among newborns of mothers with bacterial infection or colonization: a systematic review and meta-analysis

BACKGROUND

Although neonatal infections cause a significant proportion of deaths in the first week of life, little is known about the burden of neonatal disease originating from maternal infection or colonization globally. This paper describes the prevalence of vertical transmission--the percentage of newborns with neonatal infection among newborns exposed to maternal infection.

METHODS

We searched Pubmed, Embase, Scopus, Web of Science, Cochrane Library, and WHO Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection. Studies that measured prevalence of bacterial vertical transmission were included. Random effects meta-analyses were used to pool data to calculate prevalence estimates of vertical transmission.

RESULTS

122 studies met the inclusion criteria. Only seven studies (5.7%) were from very high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of infection (lab-confirmed, clinical signs), colonization, and risk factors of infection. The prevalence of early onset neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 17.2% (95%CI 6.5-27.9). The prevalence of neonatal lab-confirmed infection among newborns of colonized mothers was 0% (95% CI 0.0-0.0). The prevalence of neonatal surface colonization among newborns of colonized mothers ranged from 30.9-45.5% depending on the organism. The prevalence of neonatal lab-confirmed infection among newborns of mothers with risk factors (premature rupture of membranes, preterm premature rupture of membranes, prolonged rupture of membranes) ranged from 2.9-19.2% depending on the risk factor.

CONCLUSIONS

The prevalence of early-onset neonatal infection is high among newborns of mothers with infection or risk factors for infection. More high quality studies are needed particularly in high neonatal mortality settings to accurately estimate the prevalence of early-onset infection among newborns at risk.

Chorioamnionitis: implications for the neonate

Chorioamnionitis (CA) is characterized by inflammation of the fetal membranes. The incidence increases with decreasing gestational age at birth. When suspected on clinical criteria, pathologic assessment of the placenta should be performed. Although the mechanisms are not entirely clear, CA predisposes to premature birth, neonatal sepsis, and intraventricular hemorrhage. Its role in respiratory distress syndrome, bronchopulmonary dysplasia, and neurodevelopmental impairment is mixed. Prevention and treatment are ill-defined; antibiotics for preterm premature rupture of membranes reduce the incidence and increase the length of time to delivery. Antibiotics are recommended for infants exposed to CA while laboratory studies are being performed.

Gastrointestinal and liver disease in pregnancy

This chapter on the gastrointestinal and hepatic systems in pregnancy focusses on those conditions that are frequent and troublesome (gastro-oesophageal reflux and constipation), distressing (hyperemesis gravidarum) or potentially fatal (obstetric cholestasis, acute fatty liver of pregnancy and HELLP (haemolysis, elevated liver enzymes, low platelets) syndrome). It also highlights the clinical challenge obstetricians may face in managing rare conditions such as the Budd-Chiari syndrome, liver transplantation, primary biliary cirrhosis and Wilson disease. The clinical presentation of liver and gastrointestinal dysfunction in pregnancy is not specific, and certain 'abnormalities' may represent physiological changes of pregnancy. Diagnosis and management are often difficult because of atypical symptoms, a reluctance to use invasive investigations and concerns about the teratogenicity of the medications. The best available evidence to manage these conditions is discussed in the chapter.

Chorioamnionitis Caused by <b><i>Listeria monocytogenes</i></b>: A Case Report of Ultrasound Features of Fetal Infection

Maternal listeriosis is often associated with mild symptoms for the patient, but fetal infection can lead to severe adverse perinatal outcome. The most described antenatal symptoms are reduced fetal movements and an abnormal fetal heart rate trace. We present a case of fetal listeriosis suspected by ultrasound findings of fetal gastrointestinal compromise, neonatal diagnosis and outcome.

Listeriosis in pregnancy: a secular trend in a tertiary referral hospital in Barcelona

The purpose of this study was to describe the variation in listeriosis infection incidence during pregnancy over a 25-year period based on salient clinical and laboratory features compiled in a tertiary referral hospital and to depict the clinical characteristics of these cases. A cohort was created of all cases of listeriosis in pregnant women or their neonates (early-onset form) diagnosed between 1985 and 2010. Forty-three cases of perinatal listeriosis were diagnosed among the 82,320 hospitalised pregnant women (incidence 0.5‰). Whereas the incidence remained almost constant at 0.24‰ until 2000, an increasing incidence was observed from then on, reaching 0.86‰ during the last years of the study period. A four-fold increase in listeriosis rate during pregnancy has occurred in recent years, with poorer outcome for those cases occurring before 28 weeks and for those in which early antibiotic treatment was not provided. These results should raise the awareness of the agencies and professionals involved in prenatal care.

[Pregnancy and pandemic influenza A(H1N1) 2009. Current concepts for anaesthesia and critical care medicine]

Pregnant women are particularly vulnerable to the pandemic influenza A(H1N1) 2009. Indeed, they are at high risk of developing a severe or fatal form of the disease. The physiological changes and the "immune deviation" from cellular to humoral immunity occurring during pregnancy are hypotheses to explain this vulnerability. Severe forms, mainly viral pneumonias, require an urgent prescription of an effective antiviral therapy. Preventive measures, mainly vaccination, are essential to avoid the appearance of these severe forms.

Infections in Pregnancy

Despite advances in peripartum care, maternal morbidity and mortality associated with infections in pregnancy are increasing even in developed countries. Recently published data from the Center for Disease Control's Pregnancy Mortality Surveillance System indicates that although maternal mortality from hemorrhage, embolism, and anesthesia has declined in the United States, the proportion of maternal deaths due to infections has increased. During 1991–7 infection accounted for 13.2% of pregnancy-related deaths overall and 36.3% of abortion-related deaths. The greatest infection risk is found in blacks, older women, women without prenatal care, and women with multiple pregnancy. In the United States pregnancy rates are stable or increasing in these groups. Infection is also a major cause of morbidity and mortality for the fetus and newborn. Many perinatal infections are associated with intra-uterine growth retardation and low birthweight, or cause fetal and neonatal brain injury. Infections, particularly bacterial vaginosis and chorioamnionitis, can result in preterm delivery of live-born infants (delivery before 37 weeks gestation), or stillbirth. A multitude of immunologic, endocrinologic, metabolic, physiologic, and anatomic changes influence the likelihood and course of many infections during pregnancy. Some of these changes are intrinsic, and occur in all normal pregnancies, while others occur to varying degrees in normal and abnormal pregnancies.

The clinical content of preconception care: infectious diseases in preconception care

A number of infectious diseases should be considered for inclusion as part of clinical preconception care. Those infections strongly recommended for health promotion messages and risk assessment or for the initiation of interventions include Chlamydia infection, syphilis, and HIV. For selected populations, the inclusion of interventions for tuberculosis, gonorrheal infection, and herpes simplex virus are recommended. No clear evidence exists for the specific inclusion in preconception care of hepatitis C, toxoplasmosis, cytomegalovirus, listeriosis, malaria, periodontal disease, and bacterial vaginosis (in those with a previous preterm birth). Some infections that have important consequences during pregnancy, such as bacterial vaginosis (in those with no history of preterm birth), asymptomatic bacteriuria, parvovirus, and group B streptococcus infection, most likely would not be improved through intervention in the preconception time frame.

Murine model of pregnancy-associated Listeria monocytogenes infection

Listeria monocytogenes has been recognized as a significant pathogen, occurring worldwide, capable of causing animal and human infections. In its most severe form, listeriosis is an invasive disease that affects immunocompromised patients. Additionally, pregnant women represent a high-risk group for L. monocytogenes infection. Abortion, stillbirth or severe neonatal infection can be the serious outcome of such an infection. In an experimental murine model of pregnancy-associated listeriosis we studied the impact of L. monocytogenes on the maternal immune response and pregnancy outcome. In comparison to virgin animals, pregnant mice mounted lower levels of protective cytokines and were unable to eliminate the pathogen. The impaired maternal immune response that has been found both on the systemic and local level, facilitated bacterial multiplication in the liver, placenta and ultimately in the fetal tissues. This resulted in severe necrotizing hemorrhagic hepatitis and Listeria-induced placental necrosis, increasing the incidence of postimplantation loss and poor pregnancy outcome.

Listeria monocytogenes infection in Israel and review of cases worldwide

Listeria monocytogenes, an uncommon foodborne pathogen, is increasingly recognized as a cause of life-threatening disease. A marked increase in reported cases of listeriosis during 1998 motivated a retrospective nationwide survey of the infection in Israel. From 1995 to 1999, 161 cases were identified; 70 (43%) were perinatal infections, with a fetal mortality rate of 45%. Most (74%) of the 91 nonperinatal infections involved immunocompromised patients with malignancies, chronic liver disease, chronic renal failure, or diabetes mellitus. The common clinical syndromes in these patients were primary bacteremia (47%) and meningitis (28%). The crude case-fatality rate in this group was 38%, with a higher death rate in immunocompromised patients.

Listeria monocytogenes septicemia in a Thoroughbred foal

Listeria monocytogenes septicemia was diagnosed in a 6-day-old Thoroughbred foal. Primary clinical signs included fever, depression, diarrhea, and respiratory distress. Hematologic abnormalities included leukopenia, neutropenia, degenerative left shift, and hyperfibrinogenemia. Clinical chemistry and blood gas abnormalities included metabolic acidosis, hypoxemia, hypocapnia, hypoglycemia, and hyponatremia. Despite aggressive therapeutic intervention and intensive care, the foal died within 12 hours of admission. A postmortem examination was performed, and the primary gross lesion was bilaterally severe, focally extensive bronchopneumonia. Histopathology revealed severe subacute multifocal suppurative bronchopneumonia with necrotizing vasculitis and intralesional coccobacilli. Cultures of blood collected at admission and immediately prior to death were positive for L. monocytogenes, as were cultures obtained from lung and liver at necropsy. Immunohistochemical examination of formalin-fixed tissues revealed abundant intra- and extracellular L. monocytogenes antigen within the lung and intravascularly in multiple organs.

Ultrasound features of congenital listeriosis--a case report

We present a case of congenital listeriosis in a twin pregnancy. Presentation was prompted by decreased fetal movements and an ultrasound examination which demonstrated features similar to those observed in an adult with inflammatory conditions of the bowel, namely, small amounts of ascites, dilated loops of bowel and thickening of the bowel wall. Such ultrasound signs may be useful in consideration of the diagnosis of congenital infection and prompt diagnostic tests and appropriate interventions that assist in early therapy.