Toxoplasmosis impact on prematurity and low birth weight

Rhoptry proteins affect the placental barrier in the context of Toxoplasma gondii infection: Signaling pathways and functions

Toxoplasma gondii is an opportunistic and pathogenic obligate intracellular parasitic protozoan that is widespread worldwide and can infect most warm-blooded animals, seriously endangering human health and affecting livestock production. Toxoplasmosis caused by T. gondii infection has different clinical manifestations, which are mainly determined by the virulence of T. gondii and host differences. Among the manifestations of this condition, abortion, stillbirth, and fetal malformation can occur if a woman is infected with T. gondii in early pregnancy. Here, we discuss how the T. gondii rhoptry protein affects host pregnancy outcomes and speculate on the related signaling pathways involved. The effects of rhoptry proteins of T. gondii on the placental barrier are complex. Rhoptry proteins not only regulate interferon-regulated genes (IRGs) to ensure the survival of parasites in activated cells but also promote the spread of worms in tissues and the invasive ability of the parasites. The functions of these rhoptry proteins and the associated signaling pathways highlight relevant mechanisms by which Toxoplasma crosses the placental barrier and influences fetal development and will guide future studies to uncover the complexity of the host-pathogen interactions.

Congenital toxoplasmosis and auditory disorders: a literature review

Background

Congenital toxoplasmosis (CT) occurs mainly by primary maternal infection during pregnancy. It is estimated that the incidence of vertical transmission to the fetus is 20% and that infected women are more likely to have a premature birth or low birth weight neonate since there is an association between CT and the rate of premature birth and low birth weight. In addition to severe neurological and ophthalmic consequences, hearing disorders such as hearing loss are also among the clinical manifestations seen in children with CT. Given the above, the objective of this study is to verify what are the auditory disorders seen in children with CT.

Methods

This literature review was structured according to the PRISMA statement and based on the terms of Study Target Population, Intervention, Comparison, Outcomes, and Study Types (PICOS). To obtain the studies, the following electronic databases were consulted: PubMed, Web of Science, Scopus, and Lilacs. The combined terms used for the search were: ("auditory evoked potentials" OR "hearing" OR "hearing loss") AND ("congenital toxoplasmosis"). The selection of articles was carried out independently, blindly, by two of the authors, to minimize risk of bias.

Results

The search in the databases identified 172 articles, after excluding duplicate articles, 105 studies were identified. From the selection made by reading the titles and abstracts, 11 studies were selected for full-text reading. A total of 94 studies were excluded. An article was selected from the list of references. Therefore, 12 studies were included in the final analysis. It was observed that a significant percentage of studies sought to study the peripheral auditory pathway, verifying the occurrence or association between hearing loss and the presence of congenital infection. Only two studies evaluated the central auditory pathway, using the Brainstem Auditory Evoked Potential (BAEP) and the Frequency Following Response (FFR).

Conclusion

Toxoplasmosis affects not only the peripheral areas but central areas as well. Most studies suggest this pathology as a risk factor for both peripheral and central impairment. Research has found a greater association between CT and mild to moderate hearing loss, in addition to alterations in exams such as BAEP and FFR. These data recommend that CT be reported as a global public health problem and can help assess complications and impacts of hearing disorders as a result of CT. There is a gap about studies that retract the co-occurrence between CT and other Risk Indicators for Hearing Loss (RIHL), such as prematurity, permanence in the intensive care unit, and use of ototoxic medications, lack of longitudinal studies, that accompany the development of hearing and language of children with CT, since the consequences of this infection may be late.

Impact of chronic toxoplasmosis in pregnancy: association between maternal seropositivity for Toxoplasma gondii IgG antibodies and fetal growth restriction

Insults caused by acute infections during the gestational period on fetal development are known; however, new evidence suggests that chronic infectious diseases can also impact the maternal immune status and lead to negative consequences for the neonate. This study investigated the association between the prevalence of specific antibodies in pregnant women and alterations in fetal development at birth. A follow-up study evaluated women during the gestational period and their respective newborns at delivery time. The pregnant women were tested for the presence of antibodies to infectious agents: Toxoplasma gondii (T. gondii), cytomegalovirus (CMV), syphilis, human immunodeficiency virus (HIV), hepatitis B and C. Semi-structured questionnaires were administered to the pregnant women at the time of recruitment after obtaining informed consent. Detailed information about the newborns was extracted from medical records. The seroprevalence of chronic T. gondii infection, as determined by the presence of IgG antibodies against the protozoan, was found to be 56.2%, while the overall prevalence of CMV IgG antibodies was 96.3%. Non-primiparous pregnant women from socio-economic classes, less affluent groups, and skilled working-class individuals had higher chances of testing positive for specific T. gondii IgG antibodies. Newborns classified as small for gestational age represented 12.9% of the total. Those born to mothers seropositive for anti-T. gondii IgG antibodies were 9.4 times more likely to be born small for gestational age (p = 0.035). The results suggest that chronic T. gondii infection may contribute to higher rates of newborns with growth restriction. These findings add to a growing body of evidence regarding the impact of chronic infectious diseases on intrauterine fetal development.

Anti-Toxoplasma gondii Antibodies in European Residents: A Systematic Review and Meta-Analysis of Studies Published between 2000 and 2020

Toxoplasmosis has a major impact on animal and public health. Information regarding the seroprevalence of human Toxoplasma gondii infections from a European perspective has not yet been compiled to date. Thus, the present review summarized available resident data from the period 2000-2020. The overall seroprevalence of anti-T. gondii IgG was 32.1%, with great variability between countries (n = 30). The subgroup analysis identified different pooled prevalence data depending on the geographic area (p < 0.0001), target population (p = 0.0147), and serological diagnosis assays used (p = 0.0059). A high heterogeneity (I2 = 100%, p < 0.001; Q = 3.5e+05, d.f. = 135, p < 0.001) and degree of publication bias (Egger's test = 6.14, p < 0.001) were observed among the 134 studies considered. The occurrence of anti-T. gondii IgM, which was reported in 64.7% of studies, reached a pooled seroprevalence of 0.6%. In addition, among the eight main risk factors identified, "contact with soil", "consumption of undercooked beef", and "intake of unwashed vegetables" were the most significantly associated with infections. The fact that one-third of the European population has been exposed to T. gondii justifies extra efforts to harmonize surveillance systems and develop additional risk-factor analyses based on detailed source attribution assessment.

Seroprevalence, Risk Factors and Maternal-Fetal Outcomes of Toxoplasma gondii in Pregnant Women from WHO Eastern Mediterranean Region: Systematic Review and Meta-Analysis

BACKGROUND

The protozoan parasite Toxoplasma gondii may cause serious illness in the immunocompromised. The Toxoplasma gondii seropositive prevalence in pregnant women in WHO Eastern Mediterranean Region countries is inconsistent in the literature and it is associated with outcomes that have not be fully elucidated, hence the need for a better understanding of the pooled seroprevalence and associated maternal and fetal outcomes.

OBJECTIVE

The objective was to conduct a systematic literature review and determine the pooled prevalence of WHO Eastern Mediterranean Regional countries' pregnant women's seroprevalence of Toxoplasma gondii and the maternal-fetal outcomes.

METHODS

This quantitative study examined WHO Eastern Mediterranean countries' maternal-fetal outcomes and Toxoplasma gondii prevalence in pregnant women. The targeted population was pregnant women, while the primary outcome was seropositivity of Toxoplasma gondii, while other outcomes such as maternal and fetal associations and risk factors were determined PubMed, SCOPUS, MEDLINE, and Index Medicus for the Eastern Mediterranean Region (IMEMR) databases were searched up until 30 January 2023. The search terms used were "Toxoplasma gondii" OR "Toxoplasma infection" AND "Pregnant woman" or pregnan* OR Antenatal OR Prenatal OR Gravidity OR Parturition OR Maternal AND WHO Eastern Mediterranean Region). OpenMeta-Analyst and Jamovi were used to analyze the generated data.

RESULTS

In total, 95 of 2947 articles meeting the inclusion criteria examined Toxoplasma gondii prevalence in pregnant women from WHO Eastern Mediterranean countries. The pooled prevalence of Toxoplasma gondii in pregnant women was 36.5% (95%CI: 32.6-40.4) with a median value of 35.64%, range values of 1.38-75.30%, with 99.61% heterogeneity. The pooled seroprevalence of IgG of Toxoplasma gondii was 33.5% (95%CI: 29.8-37.2) with a median value of 33.51%, and a range values of 1.38-69.92%; the pooled seroprevalence of IgM was 3.6% (95%CI: 3.1-4.1)) with a median value of 3.62 and range values of 0.20-17.47%, while cases of pooled seroprevalence of both IgG and IgM positivity was 3.0% (95%CI: 1.9-4.4) with a median value of 2.05 and a range values of 0.05-16.62%. Of the Toxoplasma gondii seropositive women, 1281/3389 (34.8%) 174/1765 (32.9%), 1311/3101 (43.7%), and 715/1683 (40.8%) of them had contact with cats, drank unprocessed milk, ate raw or undercooked meat and ate unwashed raw vegetables, respectively. The maternal-fetal outcomes associated with Toxoplasma gondii seropositivity were a history of abortions, miscarriage, stillbirth, intrauterine fetal death, and premature birth, which were found in 868/2990 (32.5%), 112/300 (36.1%), 111/375 (25.7%), 3/157 (1.9%) and 96/362 (20.1%) of women who tested positive for Toxoplasma gondii antibodies.

CONCLUSION

The study found a high proportion of Toxoplasma gondii seroprevalence in pregnant women in the WHO Eastern Mediterranean Region, which may be linked to poor outcomes for mothers and their babies. Thus, pregnant women require monitoring and comprehensive prevention strategies for Toxoplasma gondii infection.

Sociodemographic and Clinical Factors for Microcephaly Secondary to Teratogenic Infections in Brazil: An Ecological Study

Microcephaly is a neurological condition characterized by anomalies in the growth of the cranial circumference. This study aims to examine the association between sociodemographic and clinical variables and the occurrence of secondary microcephaly in newborns in Brazil. It also aims to investigate the association between this congenital anomaly and teratogenic infections. This research adopts an observational approach with an ecological, descriptive, and analytical design. The sample includes infants aged ≤28 days and registered in the country's Live Births Information System from January 2015 to December 2021. Newborns were categorized into G1, consisting of newborns with one of the three infections (Zika, toxoplasmosis, or syphilis), and G2, consisting of newborns with two of the three infections. A total of 1513 samples were analyzed and divided into two groups: one infection (syphilis n = 423; toxoplasmosis n = 295; or Zika n = 739) and two infections (n = 56). The northeastern region of Brazil has the highest prevalence of microcephaly. Regarding the population profile, the Zika virus infection is more common among white mothers, while the syphilis infection is more common among black mothers. Among newborns with microcephaly, boys have a lower prevalence of toxoplasmosis infection, while girls have a lower prevalence of Zika virus infection. This study provides pertinent information on each infection and contributes to the epidemiologic understanding of the association between teratogenic infections and microcephaly.

Motor repertoire in 3- to 5- month-old infants with prenatal exposure to syphilis and toxoplasmosis

AIM

To characterize the motor repertoire of 3- to 5-month-old infants who were prenatally exposed to the infectious agents of syphilis and toxoplasmosis.

METHODS

Exploratory observational study that evaluated 15 exposed infants (34.4 ± 3.5 weeks gestation) recruited from a referral center. Age assessment ranged 12-20 (median 12) weeks post-term. General Movement Assessment, including the Motor Optimality Score-Revised (MOS-R), was used to assess the global quality of fidgety movements (FMs) and to quantify and detail coexisting motor patterns. Clinical variables were also collected. Later motor outcomes were obtained from medical reports when possible.

RESULTS

MOS-R ranged 10-26 (median 24). There was a higher proportion of infants with normal (80.0 %) than aberrant FMs, but the proportion of infants with reduced MOS-R (80.0 %) was higher compared to optimal MOS-R. One infant with aberrant FMs was later diagnosed with cerebral palsy. Only 13.3 % of the infants showed smooth and fluent movement character. All observed tongue movements were abnormal.

CONCLUSION

Infants had predominantly normal FMs, but with reduced MOS-R and abnormalities in the coexisting motor repertoire.

Toxoplasma Lymphadenopathy: A Comparative Diagnostic Assessment of Clinical, Serological and Histopathological Findings

Introduction

Toxoplasma Gondii (TG) is a zoonotic protozoan with extensive symptomatology. Toxoplasmic lymphadenopathy is considered an affirmative sign and is proved by a biopsy of the enlarged nodule. This study was conducted to compare the clinical, serological, and histopathological findings for the diagnosis of toxoplasmic lymphadenopathy.

Materials and Methods

This study involved biopsy examinations from twelve cases with TG lymphadenopathy. ELISA serological tests were performed for TG specific IgM and IgG immunoglobulins. PCR was done to ratify the results obtained by ELISA.

Results

The ages of the patients ranged from 15 to 48 years (mean=27.8). Most of the cases are male n=8(66.7%), while female n=4(33.3%). The asthenia was not only the most frequent clinical presentation (83.3%), but it also last longer. All cases had a positive biopsy. Eight (67.7%) cases revealed seropositivity. Two of them had positive PCR in those who were positive IgM, suggesting that the infection was acute. Six (50%) cases revealed positive IgG tests, while those with negative serology were 4(33.3%). The site of lymph nodes involvement had been assessed and mostly cervical (91.6%).

Conclusion

The histopathological results yielded 100% positive findings, thus biopsy was very important in the diagnosis and differential diagnosis of lymph nodes enlargement. The chronic phase of toxoplasmosis does not show the protozoa in the blood causing an absent DNA band for amplification of the PCR cycles, which could explain the lack of bands particular for TG. A negative serological test does not exclude toxoplasmic lymphadenitis, especially in immune-compromised patients.

Effects of Acute and Chronic Trypanosoma cruzi Infection on Pregnancy Outcomes in Mice: Parasite Transmission, Mortality, Delayed Growth, and Organ Damage in Pups

Chagas disease is caused by Trypanosoma cruzi. This study aimed to determine the effects of T. cruzi infection on fertility rate and health of the newborn pups in pregnant mice. Female mice were challenged with T. cruzi and mated at 21 days (acute parasitemic phase) or 90 days (chronic parasite persistence phase) after infection. Pups were examined for growth up to 20 days after birth; and parasite burden in brain, heart, skeletal muscle, and intestine was measured by real-time quantitative PCR. The inflammatory infiltrate, necrosis, and fibrosis in pups' heart and brain tissues were evaluated by histology. T. cruzi infection in dams delayed the onset of pregnancy, decreased the fertility rate, and led to vertical transmission of parasite to the pups. Furthermore, infected dams delivered pups that exhibited decreased survival rate, decreased birth weight, and decreased growth rate. Significantly increased inflammation, necrosis, and fibrosis of cardiac and brain tissues were noted in pups born to infected dams. Initial challenge with higher parasite dose had more detrimental effects on fertility rate and pups' health in both acutely and chronically infected dams. In conclusion, mice offer a promising model to evaluate the efficacy of new vaccines and therapeutic drugs in controlling the acute and chronic maternal T. cruzi infection and congenital transmission to newborns, and in improving the fertility rate and pups' health outcomes.

The Impact of Latent Toxoplasma gondii Infection on Spontaneous Abortion History and Pregnancy Outcomes: A Large-Scale Study

BACKGROUND

Toxoplasma gondii (TG), a zoonotic protozoan parasite, belongs to a group of TORCH infectious agents, which can cause severe damage to the fetus if a primary infection occurs during pregnancy. After primary infection, TG rests lifelong in human organisms causing a latent infection. Most studies have analyzed the consequences of acute, but not latent, TG infection. This study analyzed the impact of latent toxoplasmosis on spontaneous abortion history, pregnancy complication rate and neonatal outcome.

METHODS

IgG and IgM anti-TG antibodies were tested in 806 pregnant women who were consulted at the Timisoara Clinical Emergency Hospital between 2008 and 2010. Demographic data, obstetrical history, and data about the pregnancy complications, birth and neonate were collected for each woman and comparisons between the groups, with and without latent TG infection, were made.

RESULTS

This study did not show differences between groups regarding the history of spontaneous abortion (OR = 1.288, p = 0.333), cesarean section (OR = 1.021, p = 0.884), placental abruption (OR 0.995, p = 0.266), pregnancy-induced hypertension rate (OR 1.083, p = 0.846), secondary sex ratio (1.043, p = 0.776), 1' APGAR score at birth (p = 0.544), gestational age at birth (p = 0.491) or birth weight (p = 0.257).

CONCLUSIONS

The observed differences between the rate of pregnancy complications in the two groups of pregnant women with and without latent infection with TG, did not reach a statistical significance.