TORCH complex

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Aravind Kuchkuntla, M.B.B.S[2]

Synonyms and keywords: TORCHES; TORCH infections

Overview

TORCH group of infections include: toxoplasmosis, Treponema pallidum , rubella, cytomegalovirus, herpesvirus, hepatitis viruses, human immunodeficiency virus, and other infections such as varicella, parvovirus B19, and enteroviruses. All of these infections affect the fetus and can cause significant morbidity and mortality. Most of the infections can reach the fetus via the transplacental route or by ascending infection. The timing of infection varies with individual infections to cause severe damage. Most of the infections can result in misscarriage or fetal demise or severe clinical manifestations in the newborn. The infections can compromise normal development during infancy and have poor development. Therefore, early diagnosis and treatment plays an important role in the management of these infections to improve outcomes in the newborn.

Causes

The TORCH group of infections include bacteria, parasites and viruses:

• Congenital Toxoplasmosis is caused by coccidian parasite Toxoplasma gondii
• Congenital syphliis is caused by Treponema pallidum
• Congenital Varicella syndrome is caused by Varicella zoster virus
• Congenital rubella syndrome is caused by Rubella virus
• Congenital CMV is caused by Cytomegalovirus
• Neonatal herpes simplex is caused by HSV-1 and HSV-2

Classification

The TORCH group of infections can be classified based on the causative pathogen into the following :

• Viral causes: cytomegalovirus, hepatitis B, hepatitis C, human immunodeficiency virus, parvovirus B19, herpes virus, varicella zoster virus, rubella virus
• Bacterial causes : Treponema pallidum
• Parasite causes: Toxoplasma gondii

Differential Diagnosis

Diseases	Causative Organism	Transmission	Timing of Infection	Symptoms in the Mother	Clinical features in the newborn	Classification	Diagnosis	Treatment
Congenital Syphilis	Treponema Pallidum	Vertical	16th to 28th week	Based on the stage of Syphilis infection	Low birth weight Non-immune Hydrops Maculopapular or Vesicobullous rash on the palms and soles Interstitial Keratitis Rhinitis	Early congenital syphilis Late congnenital syphilis Stigmata	Detection of IgM aganist T.pallidum in blood collected in chordocentesis Amniotic fluid PCR for T. pallidum DNA Antenatal Ultrasound	Aqueous crystalline penicillin G
Congenital Toxoplasmosis	Toxoplasma gondii	Vertical	Third Trimester	Majority : Asymptomatic Few patients can have flu like symptoms	Low birth weight Chorioretinitis Microcephaly Intracranial calcification Spasticities and Paresis Sensorineural hearing loss	None	Amniotic fluid PCR for T.gondii DNA Detection of parasite in amniotic fluid Serology	Infected mothers without fetal infection : Spiramycin Infected mothers with established fetal infection : Pyrimethamine, sulfadiazine, and folinic acid
Congenital Varicella Syndrome	Varicella zoster virus	Vertical	13 to 20th week	Vesicular skin rash Fever	Cicatrical skin lesions Limb hypoplasia Microcephaly Autonomic instability Chorioretinitis Microphalmia and anisocoria	None	Antenatal Ultrasound Fetal MRI Amniotic fluid PCR for VZV DNA	Termination of pregnancy with severe defects No definitive treatment Preconceptional vaccination
Congenital CMV	Cytomegalovirus	Vertical	First trimester	Fever Cervical lymphadenopathy	SGA Microcephaly Sensorineural hearing loss Cataracts Petechiae and purpura Jaundice Poor sucking when feeding Hypotonia	Symptomatic Asymptomatic	Antenatal Ultrasound Amniotic Fluid PCR for CMV DNA CT brain	IV Ganciclovir Oral Valganciclovir
Congenital Rubella Syndrome	Rubella Virus	Vertical	8 to 10th week	Asymptomatic Maculopapular rash starting on the face and spreads caudally Polyarthalgia	Low birth weight VSD and PDA Cataracts, glacoma, retinopathy Sensorineural hearing loss Microcephaly Encephalitis	None	Direct isolation of the virus Viral nucleic acid quantification Detection of IgM/ IgA antibodies in fetal blood Serological Testing	Termination of pregnancy: If infection diagnosed before 18 weeks of pregnancy No definitive Treatment
Neonatal Herpes Simplex	HSV-1 and HSV-2	Direct Contact / Ascending infection from genital lesions Contact with infected people Vertical	At term	Genital herpes or Orolabial herpes	Vesicular skin lesions Oral ulcers Chorioretinitis and conjunctival erythema Encephalitis DIC Pneumonitis	Skin, eye, mouth disease (SEM) CNS Disease Disseminated Disease	Surface Cultures CSF analysis Elevated Alanine Transaminase	SEM : IV Acyclovir for 10 days Disseminated and CNS disease: IV Acyclovir for 14 to 21 days

The list of clinical manifestations in TORCH group of infections include the following:

Congenital Infection	Cardiac Findings	Skin Findings	Ocular Findings	Hepatosplenomegaly	Hydrocephalus	Microcephaly	Intracranial Calcifications	Hearing deficits
Congenital Varicella Syndrome	-	- Cicatrical Skin Lesions Skin Edema	- Micropthalmus Cataracts	✔	-	✔	✔	-
Toxoplasmosis	-	- Petechiae Purpura Maculopapular rash	- Chorioretinitis	✔	✔	✔	Diffuse intracranial calcifications	-
Congenital Syphils	-	- Petechiae Purpura Maculopapular rash	- Chorioretinitis Glaucoma	✔	-	-	-	-
Rubella	Patent ductus arteriosus (PDA) Pulmonary artery stenosis Coarctation of the aorta Myocarditis	- Petechiae Purpura	- Chorioretinitis Cataracts Glaucoma Microphthalmia	✔	✔	✔	-	✔
Cytomegalovirus (CMV)	✔	- Petechiae Purpura	Chorioretinitis	✔	-	✔	Periventricular calcifications	✔
Herpes simplex virus (HSV)	- Myocarditis	- Petechiae Purpura Vesicles	- Chorioretinitis	✔	✔	✔	-	✔
Parvovirus B19	- Myocarditis	- Petechiae Subcutaneous edema	- Chorioretinitis Cataracts	✔	-	-	-	-