Clinical Pearls & Morning Reports
Published February 7, 2018
The acronym TORCH (toxoplasmosis, other [syphilis, varicella, parvovirus B19 infection, HIV infection], rubella, cytomegalovirus infection, and herpes simplex virus infection) is often used to identify possible congenital infections. Read the latest Case Records of the Massachusetts General Hospital here.
Q: What are some of the clinical manifestations of the congenital rubella syndrome?
A: Cataracts, thrombocytopenia, bony abnormalities, and deafness are consistent with the congenital rubella syndrome.
Table 2. (10.1056/NEJMcpc1706110/T2) Manifestations of the Congenital Rubella Syndrome.
Q: How is the congenital rubella syndrome diagnosed?
A: Newborns with the congenital rubella syndrome shed rubella virus in the throat, nasopharynx, and urine. Because growth of the virus in cultured mammalian cell lines is relatively slow and cultivation and identification of the virus are labor-intensive, nucleic acid amplification tests have been developed to directly detect rubella virus RNA in clinical samples.
A: In addition to direct viral detection, evidence of the production of antibodies to rubella virus in an infant can be used to establish a diagnosis of the congenital rubella syndrome. Affected newborns produce IgM antibodies to rubella virus. These antibodies can usually be detected at birth with the use of a capture enzyme-linked immunosorbent assay; the level increases during the first 3 months of life and then declines over time. At birth, tests for IgG antibodies to rubella virus cannot be used to distinguish between transplacentally acquired maternal antibodies and antibodies produced by the neonate. However, another means of establishing a diagnosis of the congenital rubella syndrome is showing that the level of IgG antibodies to rubella virus does not substantially decrease during the first few months of life, as the maternal antibodies decay. Finally, IgG antibodies to rubella virus that are produced by infants with congenital infection are typically of low avidity; therefore, a diagnosis of the congenital rubella syndrome can be established by detecting low-avidity antibodies in the blood after the maternal antibodies have waned.
A: The estimated number of cases of the congenital rubella syndrome worldwide is still approximately 100,000 per year. Rubella and the congenital rubella syndrome have been eradicated from the Western hemisphere because of good vaccine coverage. Unfortunately, although rubella has been controlled in many countries in Europe, opposition to vaccination in some countries has prevented the elimination of rubella, and there is much work to be done. In contrast, routine vaccination against rubella has just begun in some Asian countries, including India, Thailand, China, Japan, and Indonesia. Coverage in Africa is spotty, but a few countries have introduced the vaccine. In Nigeria, vaccination is limited to private providers, and coverage is less than 10%. There is a campaign to introduce the combined measles–rubella vaccine throughout the world, and all regions have goals to eradicate both diseases.