Paeds · fetal-neonatal-and-perinatal
Congenital and perinatally acquired infections
Also known as TORCH infections · Congenital infections · Perinatally acquired infection · Mother-to-child transmitted infection · Vertical transmission of infection
Fellowship guide to congenital and perinatally acquired infections: the expanding TORCH differential, mechanisms of mother-to-child transmission, the pattern-recognition signs of congenital infection, serology and PCR interpretation, organism-specific therapy with doses (CMV, toxoplasmosis, syphilis, HSV, parvovirus, HIV, hepatitis B, rubella, Zika), and the lifelong surveillance that follows.
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Red flags
- Microcephaly, intracranial calcifications or hydrocephalus detected antenatally or at birth
- Petechiae, purpura or a 'blueberry muffin' rash in a neonate suggesting congenital infection
- Sensorineural hearing loss or chorioretinitis identified on newborn assessment
- Symmetrical intrauterine growth restriction with hepatosplenomegaly and jaundice
- Hydrops fetalis or severe fetal anaemia (consider parvovirus B19)
- Maternal primary cytomegalovirus infection, a new syphilis diagnosis or a flulike illness with rash in pregnancy
- A neonate with vesicular skin lesions, hepatitis or encephalopathy (consider herpes simplex)
- Infant of a hepatitis-B-surface-antigen-positive or HIV-positive mother without documented prophylaxis
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- Defines TORCH and recognises the expanding list of congenital pathogens
- Identifies the pattern-recognition signs of congenital infection
- Initiates appropriate serology and PCR for suspected congenital infection
- Interprets IgG avidity and IgM serology to time maternal infection
- Selects organism-specific therapy and counsels on benefit and toxicity
- Coordinates lifelong multidisciplinary surveillance after congenital infection
- Evaluation of a neonate with suspected congenital infection
- Prevention of perinatal hepatitis B and HIV transmission
- Counselling families after a diagnosis of congenital CMV
- Bedside recognition of stigmata of congenital infection
- Communication of a TORCH diagnosis and the surveillance plan
- Shared decision-making about valganciclovir for symptomatic congenital CMV
- Antenatal and perinatal infection screening and its limitations
- Clinical presentation and investigation of the infected neonate
- Long-term neurodevelopmental sequelae and follow-up
- Timing and route of mother-to-child transmission by organism
- Serological diagnosis of acute versus past maternal infection
- Treatment and prevention of congenital syphilis, CMV, toxoplasmosis and HSV
- Examination of the dysmorphic or small-for-gestational-age neonate
- History-taking and counselling in suspected congenital infection
- Structured communication of a complex chronic diagnosis
- AAP guidance on evaluation of suspected congenital CMV and other infections
- Hepatitis B birth-dose prophylaxis algorithm
- Public-health reporting and partner notification for congenital syphilis
- Recognition and initial workup of congenital infection
- Appropriate use and interpretation of maternal and neonatal serology
- Anticipatory guidance and multidisciplinary coordination
- Canadian Paediatric Society approach to congenital infection screening
- Universal hepatitis B birth-dose vaccination policy
- Perinatal HIV prevention in the absence of maternal antenatal care
Overview & Definition
Congenital and perinatally acquired infections are infections transmitted from mother to child during pregnancy, labour, delivery, or the early postnatal period. They range from clinically silent to lethal, and the damage they cause is determined less by the identity of the organism alone than by the timing of infection, the inoculum, and the maturity of the fetal immune response. The classical mnemonic TORCH - Toxoplasmosis, Other (syphilis, varicella, parvovirus), Rubella, Cytomegalovirus, and Herpes simplex - is a useful entry point, but it understates the modern list, which now firmly includes Zika virus and Chagas disease alongside the preventable perinatally transmitted hepatitis B, hepatitis C, and human immunodeficiency virus. [10]
A congenital infection is acquired in utero, almost always before birth, via transplacental haematogenous spread or ascending infection through ruptured or intact membranes. A perinatally acquired infection is contracted during passage through the birth canal or in the immediate postnatal period, while postnatally acquired infection is transmitted after birth through breastfeeding, blood exposure, or close contact. The distinction matters: congenital infection produces the structural and neurodevelopmental malformations of the TORCH phenotype, whereas perinatal acquisition more often causes acute neonatal disease such as disseminated herpes simplex or early-onset bacterial sepsis. [10]
Cytomegalovirus is the commonest congenital infection in developed countries, affecting around 0.5 to 1 per cent of all live births, and it is the leading non-genetic cause of sensorineural hearing loss and neurodevelopmental disability in children. By contrast, rubella - once the archetypal teratogen - has been driven to near-elimination by universal vaccination, and congenital rubella syndrome is now a disease of unvaccinated populations and migrant communities. Congenital syphilis, however, is resurgent globally and demands vigilance. [7]
References10ShowHide
- [1]Kimberlin DW Valganciclovir for symptomatic congenital cytomegalovirus disease. N Engl J Med, 2015.PMID 25738669
- [2]Thiébaut R, Leproust S, Chêne G, et al. Effectiveness of prenatal treatment for congenital toxoplasmosis: a meta-analysis of individual patients' data. Lancet, 2007.PMID 17223474
- [3]Corey L Once-daily valacyclovir to reduce the risk of transmission of genital herpes. N Engl J Med, 2004.PMID 14702423
- [4]Nielsen-Saines K Three postpartum antiretroviral regimens to prevent intrapartum HIV infection. N Engl J Med, 2012.PMID 22716975
- [5]Enders M Fetal morbidity and mortality after acute human parvovirus B19 infection in pregnancy: prospective evaluation of 1018 cases. Prenat Diagn, 2004.PMID 15300741
- [6]Fan L Cost-effectiveness of active-passive prophylaxis and antiviral prophylaxis during pregnancy to prevent perinatal hepatitis B virus infection. Hepatology, 2016.PMID 26509655
- [7]Gilmour LS Congenital syphilis: a review of global epidemiology. Clin Microbiol Rev, 2023.PMID 36920205
- [8]Freitas DA Congenital Zika syndrome: a systematic review. PLoS One, 2020.PMID 33320867
- [9]Gudeloglu E Congenital rubella syndrome: a short report and literature review. Trop Doct, 2023.PMID 36321169
- [10]Moodley A The term newborn: congenital infections. Clin Perinatol, 2021.PMID 34353577