Abnormal Development - TORCH Infections

From Embryology

Introduction

Materal effects should really be called environmental (in contrast to genetic) removing the association of mother with the deleterious agent. Accepting this caveat, there are several maternal effects from lifestyle, environment and nutrition that can be prevented or decreased by change which is not an option for genetic effects.

Infections, collectively grouped under the acronym TORCH for Toxoplasmosis, Other organisms (parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus) , Rubella, Cytomegalovirus and Hepatitis. See related pages on Maternal Hyperthermia and Bacterial infections.

Finally, when studying this topic remember the concept of "critical periods" of development that will affect the overall impact of the above listed factors. This can be extended to the potential differences between prenatal and postnatal effects, for example with infections and outcomes.

Environmental Links: Introduction | low folic acid | iodine deficiency | Nutrition | Drugs | Australian Drug Categories | USA Drug Categories | thalidomide | herbal drugs | Illegal Drugs | smoking | Fetal Alcohol Syndrome | TORCH | viral infection | bacterial infection | fungal infection | zoonotic infection | toxoplasmosis | Malaria | maternal diabetes | maternal hypertension | maternal hyperthermia | Maternal Inflammation | Maternal Obesity | hypoxia | biological toxins | chemicals | heavy metals | air pollution | radiation | Prenatal Diagnosis | Neonatal Diagnosis | International Classification of Diseases | Fetal Origins Hypothesis
Abnormality Links: abnormal development | abnormal genetic | abnormal environmental | Unknown | teratogens | ectopic pregnancy | cardiovascular abnormalities | coelom abnormalities | endocrine abnormalities | gastrointestinal abnormalities | genital abnormalities | head abnormalities | integumentary abnormalities | musculoskeletal abnormalities | limb abnormalities | neural abnormalities | neural crest abnormalities | placenta abnormalities | renal abnormalities | respiratory abnormalities | hearing abnormalities | vision abnormalities | twinning | Developmental Origins of Health and Disease |  ICD-11
Historic Embryology  
1915 Congenital Cardiac Disease | 1917 Frequency of Anomalies in Human Embryos | 1920 Hydatiform Degeneration Tubal Pregnancy | 1921 Anencephalic Embryo | 1921 Rat and Man | 1966 Congenital Malformations

Some Recent Findings

  • Seroprevalence of TORCH infections in women of childbearing age in Croatia.[1] "During 2005-2009, a seroepidemiological study was carried out in Croatia to define the population susceptible to common TORCH agents among pregnant and non-pregnant women of childbearing age. The IgG seroprevalence was 29.1% forT. gondii, 94.6% for rubella, 75.3% for cytomegalovirus (CMV), 78.7% for herpes simplex virus type 1 (HSV-1), and 6.8% for HSV-2. Acute toxoplasmosis and CMV infection (positive IgM antibodies with low IgG avidity) were documented in 0.25% and 0.09% women, respectively. IgM prevalence was 1.2% for both HSV-1 and HSV-2. None of the participants showed acute rubella infection. Seropositivity to T. gondii and HSV-2 varied significantly between age groups (p = 0.001 and p = 0.036, respectively). Women residing in rural regions showed a significantly higher seroprevalence rate for T. gondii, CMV, and HSV-1 than urban women (T. gondii: 44.0% vs. 25.4%, p < 0.001; CMV: 85.0% vs. 73.1%, p = 0.018; HSV-1: 86.0% vs. 76.4%, p = 0.041)."
  • Routine TORCH screening is not warranted in neonates with subependymal cysts.[2] "Congenital infections are associated with a wide variety of clinical symptoms, including subependymal cysts (SEC). ...The co-occurrence of TORCH congenital infections in infants with SEC is rare. Routine TORCH screening in neonates with SEC does not seem warranted."

Toxoplasmosis

The causal agent of Toxoplasmosis is the protist Toxoplasma gondii. This unicellular eukaryote is a member of the phylum Apicomplexa which includes other parasites responsible for a variety of diseases (malaria, cryptosporidiosis). The diagnosis and timing of an infection are diagnostically based on serological tests.

Toxoplasmosis lifecycle Toxoplasma tachyzoites
Toxoplasmosis lifecycle Toxoplasma tachyzoites

Recent findings suggest that pre-pregnancy immunization against toxoplasmosis may not protect against reinfection by atypical strains.

Other Organisms

A general term covering a ranges of viruses: parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus.

Human immunodeficiency virus

Links: Abnormal Development - Viral Infection

Rubella

Rubella virus (Latin, rubella = little red) is also known as "German Measles" due to early citation in German medical literature. Infection during pregnancy can cause congenital rubella syndrome (CRS) with serious malformations of the developing fetus. The type and degree of abnormality relates to the time of maternal infection.

Infant rubella virus.jpg Rubella virus.jpg
Infant rubella virus Rubella virus (electron micrograph

Cytomegalovirus

Viral infection causes systemic infection and extensive brain damage and cell death by necrosis.

Cytomegalovirus.jpg

References

  1. <pubmed>20476874</pubmed>
  2. <pubmed>20227842</pubmed>

Reviews

Articles

Search Pubmed

June 2010 "TORCH Infections" All (183) Review (37) Free Full Text (18)

Search Pubmed: TORCH Infections | maternal infections | teratogens


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Cite this page: Hill, M.A. (2024, March 28) Embryology Abnormal Development - TORCH Infections. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Abnormal_Development_-_TORCH_Infections

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G