Congenital toxoplasmosis among Iranian neonates: a systematic review and meta-analysis

Assessment of simultaneous IgM, IgG avidity, and IgA testing in diagnosis of acute toxoplasmosis in pregnant women: a systematic review and meta-analysis study

BACKGROUNDS

Toxoplasma gondii is a relatively common parasite with a global prevalence that can cause toxoplasmosis. This infection usually does not have clear symptoms, so timely and accurate detection plays a major role in the treatment of this disease. This study reviewed Toxoplasma antibodies dependent serologic tests in pregnancy, assessing their diagnostic effectiveness to guide healthcare providers, particularly obstetricians and gynecologists.

METHODS

In this systematic review and meta-analysis, we utilized four different databases for our search and adhered to the PRISMA guidelines to collect pertinent studies in duration of 2000 to April 2024. After carefully evaluating the inclusion/exclusion criteria list, we ultimately selected 67 qualifying studies for our analysis and subjecting the obtained data to statistical scrutiny.

RESULTS

Data analysis revealed that the pooled seroprevalence of IgM anti-T. gondii among pregnant women tested were 2.1% (95% CI = 1.67 to 3.03). Moreover, the weighted seroprevalence rate estimate of low IgG avidity in IgM-positive pregnant women was 30% (95% CI = 28 to 31) and the seroprevalence of IgA in IgM-positive pregnant women was 43% (95% CI = 18 to 70). Combining the IgG avidity test results with those of IgM and IgA can significantly improve the accuracy of diagnosing recent and past Toxoplasma infections.

CONCLUSIONS

This approach is particularly valuable for pregnant women, as it improves the reliability of serological test outcomes and helps to provide timely treatment and mitigate irreversible complications associated with toxoplasmosis.

Study of anti-Toxoplasma gondii effect of mPEG-PCL copolymeric loaded with pyrimethamine, in vitro

The discovery of new drugs with minimal toxicity is crucially important in the search for effective treatments for toxoplasmosis. The study aimed to assess the effectiveness of pyrimethamine-loaded mPEG-PCL copolymeric nanoparticles (mPEG-PCL-Pyr) against Toxoplasma gondii (T. gondii) tachyzoites. The nanoparticles were fabricated using a nano-precipitation method and characterized using DLS and AFM. Through MTT assay, the anti-toxoplasmic activity was gauged. Healthy and infected cell viability, infection index, proliferation index, plaque count, and size were evaluated. Results indicated a maximum drug loading capacity of 11.23% in the nanoparticles. Toxicity testing on Vero cells infected with tachyzoites revealed notable cytotoxic effects at pyrimethamine-equivalent concentrations of 20 and 40 mg/mL in the mPEG-PCL copolymeric nanoparticle formulation. However, as the results indicated, the administration of mPEG-PCL-Pyr resulted in the reduction of intracellular proliferation, infection index, and the number and size of plaques in comparison to uninfected treated cells (P < 0.05). The synthesized Nano drug exhibited slightly better performance than pyrimethamine, despite the lack of statistical significance in the observed distinction (p > 0.05). The study demonstrated that mPEG-PCL copolymeric nanoparticles containing pyrimethamine effectively impede the in vitro replication of T. gondii. The study demonstrated that mPEG-PCL copolymeric nanoparticles containing pyrimethamine effectively impede the in vitro replication of T. gondii. The impact of pyrimethamine resembled that of the synthesized nano-drug on T. gondii tachyzoites, suggesting the potential of these nanoparticles as a promising avenue for toxoplasmosis treatment.

Effective factors in the pathogenesis of Toxoplasmagondii

Toxoplasma gondii (T. gondii) is a cosmopolitan protozoan parasite in humans and animals. It infects about 30 % of the human population worldwide and causes potentially fatal diseases in immunocompromised hosts and neonates. For this study, five English-language databases (ScienceDirect, ProQuest, Web of Science, PubMed, and Scopus) and the internet search engine Google Scholar were searched. This review was accomplished to draw a global perspective of what is known about the pathogenesis of T. gondii and various factors affecting it. Virulence and immune responses can influence the mechanisms of parasite pathogenesis and these factors are in turn influenced by other factors. In addition to the host's genetic background, the type of Toxoplasma strain, the routes of transmission of infection, the number of passages, and different phases of parasite life affect virulence. The identification of virulence factors of the parasite could provide promising insights into the pathogenesis of this parasite. The results of this study can be an incentive to conduct more intensive research to design and develop new anti-Toxoplasma agents (drugs and vaccines) to treat or prevent this infection. In addition, further studies are needed to better understand the key agents in the pathogenesis of T. gondii.

Seroprevalence of Toxoplasmosis in Puerperal Women Treated at a Tertiary Referral Hospital

OBJECTIVE

 To evaluate the seroprevalence of toxoplasmosis among puerperal women cared for at a tertiary university hospital and the level of understanding of these puerperal women about toxoplasmosis, vertical transmission, and its prophylaxis.

METHODS

 For this cross-sectional study, we evaluated 225 patients using presential interviews, prenatal documentation, and electronic medical records. Data were stored using Research Electronic Data Capture (REDCap) software. Prevalence rates were estimated by the presence of reactive IgG antibodies against Toxoplasma gondii. Data analysis was performed using the chi-square test and calculation of the odds ratio (OR). Seroreactivity to T. gondii and exposure variables (age, educational level, and parity) were analyzed using a confidence interval (95%CI) and a significance level of 5% (p < 0.05).

RESULTS

 The seropositivity rate for T. gondii was 40%. There was no association between seroprevalence and age. Primiparity was a protective factor against seropositivity and low education was a risk factor.

CONCLUSION

 Knowledge of T. gondii infection and its transmission forms was significantly limited, presenting a risk for acute maternal toxoplasmosis and vertical transmission of this protozoan. Increasing the education level regarding the risk of toxoplasmosis during pregnancy could reduce the rates of infection and vertical transmission of this parasite.

Identification and multilocus genotyping of Toxoplasma gondii isolates from congenital infection in north of Iran

Congenital toxoplasmosis can cause severe consequences in the fetus, such as spontaneous abortion which is affected by parasite strain. Also, recent studies revealed the high genetic diversity of Toxoplasma gondii. This study aims to investigate the serological status of T. gondii in pregnant women, multilocus genotyping in aborted fetuses' tissue, and archived formalin-fixed paraffin-embedded placenta. This study was performed on 100 pregnant women with spontaneous abortion and their aborted fetuses, and 250 of the archived placentae in Iran. The blood and tissue were examined for seroprevalence and genotype determination of T. gondii using ELISA and multilocus nested-PCR-RFLP, respectively. Anti-T. gondii IgG and IgM were detected in 68 samples (68%) and 1 (1%) out of 100 serums. Toxoplasma DNA was identified in 1 (1%) aborted fetuses' tissue and 32 (12.8%) placenta samples. Overall, ten positive DNA samples were successfully genotyped, and five genotypes were recognized (ToxoDB#1, #2, #10, #27, and #48). The obtained results indicated congenital toxoplasmosis is a severe risk in this region. As type I is highly pathogen and can lead to severe complications, the prevention of the infection should be considered in seronegative pregnant women.

A Systematic Review to Evaluate a Possible Association Between Congenital Toxoplasmosis and Preterm Labor

BACKGROUND

Congenital toxoplasmosis (CT) is a widespread infection in several countries, and it is defined as an infection of a fetus, newborn, or infant under 1 year of age. Moreover, it represents a thread to pregnant women globally. The objective of our study is to evaluate a potential association between prematurity and CT and whether intrauterine transmission impacts gestational length during pregnancy.

METHODS

PubMed, Cochrane Library and Google Scholar databases were searched from 1950 to 2019. Case-control studies, retrospective, and prospective cohort studies were eligible. Seven studies were included from a total of 314. The Newcastle-Ottawa scale was used to establish the quality of the articles included.

RESULTS

Based on our review, an association between CT and preterm labor was not established, which may reflect heterogeneity in screening, treatments administered, and differing reported incidences of CT across continents over 69 years. A multicenter prospective cohort study powered to investigate a potential association is indicated.

CONCLUSION

Further studies are needed including multicenter prospective cohort studies powered to investigate key clinical associations such as vertical transmission and preterm birth.

From Fetal to Neonatal Neuroimaging in TORCH Infections: A Pictorial Review

Congenital infections represent a challenging and varied clinical scenario in which the brain is frequently involved. Therefore, fetal and neonatal neuro-imaging plays a pivotal role in reaching an accurate diagnosis and in predicting the clinical outcome. Congenital brain infections are characterized by various clinical manifestations, ranging from nearly asymptomatic diseases to syndromic disorders, often associated with severe neurological symptoms. Brain damage results from the complex interaction among the infectious agent, its specific cellular tropism, and the stage of development of the central nervous system at the time of the maternal infection. Therefore, neuroradiological findings vary widely and are the result of complex events. An early detection is essential to establishing a proper diagnosis and prognosis, and to guarantee an optimal and prompt therapeutic perinatal management. Recently, emerging infective agents (i.e., Zika virus and SARS-CoV2) have been related to possible pre- and perinatal brain damage, thus expanding the spectrum of congenital brain infections. The purpose of this pictorial review is to provide an overview of the current knowledge on fetal and neonatal brain neuroimaging patterns in congenital brain infections used in clinical practice.

One severe case of congenital toxoplasmosis in China with good response to azithromycin

BACKGROUND

Most infants infected with Toxoplasma gondii are completely asymptomatic at birth, yet they may develop ocular and neurological sequelae in the first few months of life. Cases of congenital toxoplasmosis with severe jaundice early after birth combined with pancytopenia and splenomegaly are extremely rare. Here, we report on a rare case of congenital toxoplasmosis presenting with severe jaundice and hemolysis early after birth combined with pancytopenia and splenomegaly.

CASE PRESENTATION

A male preterm infant with severe jaundice and splenomegaly was admitted to our department. Laboratory examinations revealed severe hyperbilirubinemia, increased reticulocytes, and pancytopenia. After comprehensive analysis and examination, the final diagnosis was congenital toxoplasmosis, and the infant was treated with azithromycin and subsequently trimethoprim-sulfamethoxazole. Regular follow-up revealed congenital toxoplasmosis in both eyes, which was surgically treated, while neurofunctional assessment results were unremarkable. In this case of congenital toxoplasmosis combined with severe jaundice, we treated the infant with two courses of azithromycin, followed by trimethoprim-sulfamethoxazole after the jaundice resolved. Clinical follow-up indicated that this treatment was effective with few side effects; thus, this report may serve as a valuable clinical reference.

CONCLUSIONS

Timely diagnosis and adequate treatment are closely associated with congenital toxoplasmosis-related prognosis. Infants with congenital toxoplasmosis require long-term follow-up, focusing on nervous system development and ophthalmology.

Molecular and serological study on congenital toxoplasmosis in newborn of Shiraz, Southern Iran

Toxoplasmosis is a zoonotic disease caused by an obligatory intracellular parasite, Toxoplasma gondii. The congenital form of the disease is a significant health problem around the world. This study aimed to determine the incidence of congenital toxoplasmosis in the newborn of Shiraz, Southern Iran, between 2013 and 2018. A total of 2498 blood samples of neonates were randomly collected by a standard heel puncture technique and dried on Guthrie cards from Shiraz newborn screening center. We provided questionnaire forms for mothers according to their demographic characteristics, such as age, place of residence, history of having cats as pet, and literacy level. ELISA immunocapture and PCR assays were applied to detect anti-Toxoplasma IgM and the parasite DNA in dried blood spot samples. The anti-Toxoplasma IgM antibody was detected in two out of the 2498 infants. Moreover, borderline titers were observed in 3 samples, which were considered suspicious, so these were retested after 18 months to detect IgG against Toxoplasma. Positive IgG titer was observed in two infants who had a positive IgM level. The genome of Toxoplasma was detected in one sample out of 2498. No significant differences were seen between the epidemiological factors with congenital infection. The incidence of congenital toxoplasmosis is estimated at 0.08% of studied samples. It seems that this incidence could present to the health ministry as a logical research achievement for the national screening program of newborns in Iran.

Detection of toxoplasmosis in aborted women in Alexandria, Egypt using ELISA and PCR

Toxoplasmosis is a worldwide infection that can be acquired through the ingestion of tissue cysts in poorly cooked meat, and/or oblivious intake of sporulated oocysts in cat faeces, and transplacental. The infection in pregnant women is mainly asymptomatic. It produces abortion or congenital infection. The present study aimed to test the utility of polymerase chain reaction (PCR) on placental tissues in comparison to enzyme-linked immunosorbent assay (ELISA) to detect infections with Toxoplasma gondii in aborted women presented to Al-Shatby Maternity Hospital, Alexandria University, Egypt. Specific Toxoplasma gondii IgG and IgM were detected in serum by ELISA. Placental tissues from each participant were subjected to DNA extraction and PCR amplification. It was found that overall seroprevalence was 73%, DNA was detected in placenta tissues by using PCR analysis in 46% of cases. {× 2 (p) 18.124(< 0.001)}. Toxoplasma IgG/IgM by ELISA was positive in 23% of the cases, 20% showed amplified DNA by PCR. Positive IgG without IgM was seen in 27% cases, only 2% of them were positive by PCR. Moreover, positive PCR among positive ELISA IgM aborted women was 21 of the 23 cases. Positive PCR was obtained in three seronegative women. Our results showed that PCR sensitivity was 58.90 specificity 88.89, positive predictive value was 93.48%, and negative predictive value 44.44%. Although ELISA assay is still the gold standard of diagnosis of Toxoplasmosis, other diagnostic modalities are highly required particularly in those ELISA seronegative cases. PCR can be used as a sensitive and precise modality.

A serological investigation and genotyping of Toxoplasma gondii among Iranian blood donors indicates threat to health of blood recipients

BACKGROUND

Toxoplasmosis is a zoonotic disease in animals and human caused by the intracellular obligatory protozoan named Toxoplasma gondii. The purpose of this study was to evaluate the sero-molecular prevalence and genotyping T. gondii among healthy blood donors in north of Iran.

METHODS

In this cross-sectional study, 400 blood donors participated from all Blood Transfusion Organization (BTO) in Mazandaran province during October and November 2014. The blood samples were investigated for seroprevalence, DNA detection and genotyping of T. gondii using ELISA, nested-PCR, and Multilocus nested-PCR-RFLP methods respectively.

RESULTS

Among all of blood donors, 294 (73.5 %) and 9 (2.2 %) cases were seropositive for anti-T. gondii IgG and IgM antibodies. T. gondii DNA was detected in 7 samples. Four genotype of T. gondii were identified in blood donors samples (Genotype ToxoDB#1, #2, #10 and #27), which 50 % of T. gondii strains were highly pathogenic.

CONCLUSIONS

Taking into account survive T. gondii in blood transfusion bag, the high prevalence of T. gondii and existence of pathogenic genotypes in Iranian blood donors, it seems that T. gondii screening should be performed at the BTO to prevent complications of toxoplasmosis in blood recipients.