Abnormal Development - TORCH Infections

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Introduction

Toxoplasmosis lifecycle

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 Infections | Viral Infection | Bacterial Infection | Zoonotic Infection | Toxoplasmosis | Malaria | Iodine Deficiency | Maternal Diabetes | Maternal Hyperthermia | Maternal Inflammation | Biological Toxins | Chemicals | Heavy Metals | Radiation | Prenatal Diagnosis | Neonatal Diagnosis | International Classification of Diseases | Fetal Origins Hypothesis

Viral Links: TORCH Infections | Cytomegalovirus | Hepatitis Virus | HIV | Measles Virus | Parvovirus | Polio Virus | Rubella Virus | Chickenpox | Lymphocytic Choriomeningitis Virus | Vaccination | Environmental

Abnormality Links: Introduction | Genetic | Environmental | Unknown | Teratogens | Cardiovascular | Coelomic Cavity | Endocrine | Gastrointestinal Tract | Genital | Head | Integumentary | Musculoskeletal | Limb | Neural | Neural Crest | Renal | Respiratory | Sensory | Twinning | Fetal Origins Hypothesis | ICD-10

Some Recent Findings

Seroprevalence of TORCH infections in women of childbearing age in Croatia. "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. "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

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

Links: Toxoplasmosis

Other Organisms

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

Susan B Brogly, Mark J Abzug, D Heather Watts, Coleen K Cunningham, Paige L Williams, James Oleske, Daniel Conway, Rhoda S Sperling, Hans Spiegel, Russell B Van Dyke Birth defects among children born to human immunodeficiency virus-infected women: pediatric AIDS clinical trials protocols 219 and 219C. Pediatr. Infect. Dis. J.: 2010, 29(8);721-7 PMID:20539252

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. This association between infection and abnormal development was first identified in 1941.The type and degree of abnormality relates to the time of maternal infection.

Infant rubella virus	Rubella virus (electron micrograph

Links: Rubella Virus

Cytomegalovirus

Human cytomegalovirus (HCMV, Greek, cyto = "cell", megalo = "large") or Human Herpesvirus 5 (HHV-5) is a member of the herpes virus family. A viral infection that causes systemic infection and extensive brain damage and cell death by necrosis. HCMV infection is ranked as one of the most common infections in adults, with the seropositive rates ranging from 60–99% globally. In Western countries, adults with advanced AIDS prior to the introduction of highly active antiretroviral therapy (HAART) this virus also a cause of blindness (CMV retinitis) and death in patients.

Estimated annual number of United States children with long-term sequelae caused by various disease conditions. Congenital cytomegalovirus data are from a literature review, with varying collection periods spanning multiple years. Assumes 4 million live births per year and 20 million children less than 5 years of age. Where applicable, numbers represent means of published estimates. All estimates should be considered useful for rough comparisons only since surveillance methodology, time periods, and diagnostic accuracy varied by study.

Links: Cytomegalovirus | Torch Infections | Trisomy 21 | Fetal Alcohol Syndrome

Hepatitis

Hepatitis (inflammation of the liver) is caused in humans by one of 7 viruses (A, B, C, D, E) with the 2 additional F has not been confirmed as a distinct genotype; and G is a newly described flavivirus. "All of these viruses can cause an acute disease with symptoms lasting several weeks including yellowing of the skin and eyes (jaundice); dark urine; extreme fatigue; nausea; vomiting and abdominal pain. It can take several months to a year to feel fit again." (CDC text). Virus particles measure 42nm in overall diameter and contain a 27nm diameter DNA-based core.

Hepatitis Transmission Risk to the Fetus

• Hepatitis A - Fetal transmission of virus occurs with extreme rarity.
• Hepatitis B - Can occur as a consequence of intrapartum exposure, transplacental transmission, and breastfeeding.

20%–30% of HBsAg-positive/HbeAg-negative women will transmit virus to their infants. 90% of HBsAg- and HBeAg-positive women will transmit virus to their infants. Immunoprophylaxis at birth with both HBIG and Hepatitis B vaccine within 12 hours of birth decreases the risk of transmission. Passive (HBIG) and active immunization is 85%–95% effective in preventing neonatal HBV infection.

• Hepatitis C - The overall risk of transmission is approximately 5%–10% with unknown maternal viral titers.

All pregnant women with HCV should have viral titers performed.

Data: Hepatitis and reproduction

Links: Hepatitis Virus

References

Reviews

Joshua P Nickerson, Beat Richner, Ky Santy, Maarten H Lequin, Andrea Poretti, Christopher G Filippi, Thierry A G M Huisman Neuroimaging of pediatric intracranial infection--part 2: TORCH, viral, fungal, and parasitic infections. J Neuroimaging: 2012, 22(2);e52-63 PMID:22309611

Sidra Ishaque, Mohammad Yawar Yakoob, Aamer Imdad, Robert L Goldenberg, Thomas P Eisele, Zulfiqar A Bhutta Effectiveness of interventions to screen and manage infections during pregnancy on reducing stillbirths: a review. BMC Public Health: 2011, 11 Suppl 3();S3 PMID:21501448

Barbara J Stegmann, J Christopher Carey TORCH Infections. Toxoplasmosis, Other (syphilis, varicella-zoster, parvovirus B19), Rubella, Cytomegalovirus (CMV), and Herpes infections. Curr Womens Health Rep: 2002, 2(4);253-8 PMID:12150751

A Helfgott TORCH testing in HIV-infected women. Clin Obstet Gynecol: 1999, 42(1);149-62; quiz 174-5 PMID:10073308

E R Newton Diagnosis of perinatal TORCH infections. Clin Obstet Gynecol: 1999, 42(1);59-70; quiz 174-5 PMID:10073301

A Greenough The TORCH screen and intrauterine infections. Arch. Dis. Child. Fetal Neonatal Ed.: 1994, 70(3);F163-5 PMID:8198407

TORCH syndrome and TORCH screening. Lancet: 1990, 335(8705);1559-61 PMID:1972489

Articles

Tatjana Vilibic-Cavlek, Suncanica Ljubin-Sternak, Mirela Ban, Branko Kolaric, Mario Sviben, Gordana Mlinaric-Galinovic Seroprevalence of TORCH infections in women of childbearing age in Croatia. J. Matern. Fetal. Neonatal. Med.: 2011, 24(2);280-3 PMID:20476874

Marawan A Abu-Madi, Jerzy M Behnke, Haydee A Dabritz Toxoplasma gondii seropositivity and co-infection with TORCH pathogens in high-risk patients from Qatar. Am. J. Trop. Med. Hyg.: 2010, 82(4);626-33 PMID:20348511

Jan M Kriebs Breaking the cycle of infection: TORCH and other infections in women's health. J Midwifery Womens Health: , 53(3);173-4 PMID:18455090

S Singh Prevalence of torch infections in Indian pregnant women. Indian J Med Microbiol: , 20(1);57-8 PMID:17657031

Sherif A Abdel-Fattah, Abha Bhat, Sebastian Illanes, Jose L Bartha, David Carrington TORCH test for fetal medicine indications: only CMV is necessary in the United Kingdom. Prenat. Diagn.: 2005, 25(11);1028-31 PMID:16231309

Search Pubmed

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

Search Pubmed: TORCH Infections | maternal infections | teratogens

Glossary Links

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Dr Mark Hill 2013, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G