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Disease Profile

Congenital toxoplasmosis

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

Unknown

Age of onset

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ICD-10

#N/A

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Mother-to-child transmission of toxoplasmosis; Toxoplasma embryofetopathy; Toxoplasma embryopathy

Categories

Congenital and Genetic Diseases; Nervous System Diseases; Newborn Screening;

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 858

Definition
Congenital toxoplasmosis (CTX) is an embryo-fetopathy characterized by ocular, visceral or intracranial lesions secondary to maternal primo-infection by Toxoplasma gondii (Tg).

Epidemiology
Given its infectious origin, incidence of CTX is variable over time and geographically. Screening policies and methods also influence prevalence calculation. A low estimate of the overall prevalence might be of 1:3,030 births, with symptomatic cases at 1:29,000 births.

Clinical description
Clinical presentation is highly variable. Earlier infection is generally more severe but less frequent. Infections in the first trimester may result in miscarriage or fetal death in utero, whereas later ones may be limited to ocular anomalies. Intracranial calcifications, microor macrocephaly, ventricular dilatation and hydrocephalus, hepatomegaly, splenomegaly, cardiomegaly, ascites and intrauterine growth retardation can be observed in infected fetuses. When present, clinical manifestations at birth are maculopapular rash, jaundice, generalized lymphadenopathy, organomegaly, central nervous system anomalies and hyperbilirubinemia, anemia, and thrombocytopenia. The first neurologic manifestation is seizures; nystagmus, hypotonia and, later, delay of developmental milestones acquisition can be seen. The chorioretinitis intracranial calcifications hydrocephalus triad is present in 10% of cases. Ocular involvement may develop after months or years, most frequently with chorioretinitis, followed by microphthalmia and strabismus. Visual impairment is highly dependent on the parasite genotype, and probably on prenatal and postnatal treatments.

Etiology
CTX is caused by the mother's primo-infection by Tg, an intracellular protozoan parasite of the Apicomplexa phylum, and transmission to the fetus by trans-placental infection. Nearly 25% of exposed fetuses are infected. Mother is infected by Tg through ingestion of ooccysts present in cat faeces and soil, or of cysts present in uncooked meat.

Diagnostic methods
Diagnosis relies on evidence of infection in the fetus, the infant or the child with a history of maternal primo-infection during pregnancy or up to 6 months before conception. Given the poor specificity of clinical signs observed in Tg infection, serological findings and PCR amplification of Tg specific sequences are the main diagnostic clues. RT-PCR targeting repetitive DNA segments was reported to be more sensitive and not less specific than previous tests.

Differential diagnosis
Differential diagnosis includes other congenital infections (rubella, CMV, HSV1 and HSV2, regrouped with Tg infection in the TORCH syndrome) and pseudo-TORCH and Aicardi-Goutières syndromes (see these terms).

Antenatal diagnosis
Fetal ultrasonography and/or magnetic resonance imaging (MRI) detect and characterize brain, cardiac or placental anomalies. Diagnosis is confirmed only with serological or PCR findings of Tg infection in the mother and the amniotic fluid. Amniocentesis should be performed at least 4 weeks after the mother's seroconversion to avoid false negative results due to latency.

Management and treatment
In several countries, a systematic serological status follow-up of each pregnant woman is organized in order to diagnose and treat early maternal and fetal infections. Seronegative pregnant women are tested regularly to detect seroconversion, with, if needed, a spiramycin-based treatment, expected to reduce vertical transmission. A pyrimethamine-sulphonamide combination is recommended in case of confirmed fetal infection. Neonates should also be treated even if they are asymptomatic at birth since complications may occur later. The benefits of prenatal and postnatal treatment remain to be assessed.

Prognosis
Prognosis is highly dependent on the parasite genotype, the gestational age at maternal infection and on the timing of prenatal and postnatal treatment.

Visit the Orphanet disease page for more resources.

Symptoms

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormality of retinal pigmentation
0007703
Premature birth
Premature delivery of affected infants
Preterm delivery

[ more ]

0001622
5%-29% of people have these symptoms
Anemia
Low number of red blood cells or hemoglobin
0001903
Ascites
Accumulation of fluid in the abdomen
0001541
Cardiomegaly
Enlarged heart
Increased heart size

[ more ]

0001640
Cerebral calcification
Abnormal deposits of calcium in the brain
0002514
Cognitive impairment
Abnormality of cognition
Cognitive abnormality
Cognitive defects
Cognitive deficits
Intellectual impairment
Mental impairment

[ more ]

0100543
Diarrhea
Watery stool
0002014
Elevated hepatic transaminase
High liver enzymes
0002910
Failure to thrive in infancy
Faltering weight in infancy
Weight faltering in infancy

[ more ]

0001531
Global developmental delay
0001263
Hearing impairment
Deafness
Hearing defect

[ more ]

0000365
Hepatomegaly
Enlarged liver
0002240
Hydrocephalus
Too much cerebrospinal fluid in the brain
0000238
Intrauterine growth retardation
Prenatal growth deficiency
Prenatal growth retardation

[ more ]

0001511
Jaundice
Yellow skin
Yellowing of the skin

[ more ]

0000952
Lymphadenopathy
Swollen lymph nodes
0002716
Macule
Flat, discolored area of skin
0012733
Microcephaly
Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference

[ more ]

0000252
Microphthalmia
Abnormally small eyeball
0000568
Muscular hypotonia
Low or weak muscle tone
0001252
Nystagmus
Involuntary, rapid, rhythmic eye movements
0000639
Seizure
0001250
Thrombocytopenia
Low platelet count
0001873
Ventriculomegaly
0002119
Visual impairment
Impaired vision
Loss of eyesight
Poor vision

[ more ]

0000505

Diagnosis

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Newborn Screening

  • Baby's First Test is the nation's newborn screening education center for families and providers. This site provides information and resources about screening at the local, state, and national levels and serves as the Clearinghouse for newborn screening information.
  • The Newborn Screening Coding and Terminology Guide has information on the standard codes used for newborn screening tests. Using these standards helps compare data across different laboratories. This resource was created by the National Library of Medicine.
  • National Newborn Screening and Global Resource Center (NNSGRC) provides information and resources in the area of newborn screening and genetics to benefit health professionals, the public health community, consumers and government officials.

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.

In-Depth Information

  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.