Dermatologic Manifestations of Rubella Workup
- Author: Peter C Lombardo, MD; Chief Editor: Dirk M Elston, MD more...
In a healthy child or adolescent, the diagnosis of rubella is made on a clinical basis, and a laboratory workup is not necessary.
A WBC count, if performed, may be lower than normal, as in many viral infections, with increased percentages in the lymphocyte count. In those very rare cases in which encephalitis is present, lymphocytes are present in the cerebrospinal fluid (CSF). If necessary, rubella virus can be cultured from the nasopharynx, blood, urine, and CSF.
If the diagnosis is in doubt, a rising titer of immunoglobulin M (IgM) antibody over a 2-week period indicates a recent infection. Two specific antibodies are associated with Rubella. The first to appear is IgM antibody, which rises and peaks 7-10 after infection and then tapers off after several weeks. One exception to this rule is in the infected newborn, in whom IgM may be detected for months to a year. The immunoglobulin G (IgG) antibody develops more slowly but remains positive for life. It confers immunity against repeat infection. Therefore, the presence of IgM antibody indicates a recent infection, whereas IgG antibody indicates an old infection and immunity. IgG antibody may also indicate immunity caused by the measles, mumps, rubella (MMR) vaccine.
From a public health standpoint, attempting to confirm a rubella infection in a pregnant woman or a newborn infant is important; a pregnant woman exposed to rubella should be tested immediately for a rubella-specific antibody. The presence of rubella-specific IgG is evidence that the patient is immune. If the test result is negative, repeat the test again in 3-4 weeks, and repeat the test on the first specimen. If an antibody is present in the second test and not in the first test, an infection has occurred. If the second test result is negative, repeat the test in 6 weeks, and, again, test it with the first specimen. A negative test result in both specimens means an infection has not occurred, whereas if the last specimen is positive and the first specimen is negative, then an infection has occurred.
An infant with congenital rubella syndrome shows the IgG antibody from the mother, which disappears in a few months, and an elevated IgM antibody level because of antibody production by the infant. The presence of the IgM antibody usually indicates recent infection because IgM does not cross the placenta from the mother as does IgG. After 1 year, confirming the diagnosis of congenital rubella syndrome in an infant with serology alone is very difficult.
The histopathologic features of the skin are those of the Togaviruses, namely, a light perivascular infiltrate of lymphocytes with mild endothelial swelling. If petechiae or purpura are present clinically, extravasation of erythrocytes may be observed.
[Guideline] Centers for Disease Control and Prevention. Recommendations from an Ad Hoc Meeting of the WHO Measles and Rubella Laboratory Network (LabNet) on Use of Alternative Diagnostic Samples for Measles and Rubella Surveillance. MMWR Morb Mort Wkly Rpt. 2008 Jun. 57(24):657-660. [Full Text].
Danovaro-Holliday MC, LeBaron CW, Allensworth C, et al. A large rubella outbreak with spread from the workplace to the community. JAMA. 2000 Dec 6. 284(21):2733-9. [Medline].
Centers for Disease Control and Prevention. Rubella Outbreak-Westchester County, New York 1997-1998. MMWR Morb Mort Wkly Rpt. 1999 Jul. 48(26):560-563. [Full Text].
Schluter WW, Reef SE, Redd SC, Dykewicz CA. Changing epidemiology of congenital rubella syndrome in the United States. J Infect Dis. 1998 Sep. 178(3):636-41. [Medline].
Youngdahl K. Rubella Elimination in the Americas. History of Vaccines.org. Available at http://www.historyofvaccines.org/content/blog/rubella-elimination-americas. April 30, 2015; Accessed: October 10, 2015.
Giles JP, Balsamo MR, Green RH, et al. Rubella: Studies on the Natural History and Prevention of the Disease. J Pediatr. 1963. 63:816-7.
American Association for Clinical Chemistry. Rubella. Lab Tests Online. Available at http://www.labtestsonline.org/. Accessed: April 8, 2009.
Jensen V. Measles on the rise as vaccinations fall, study reports. Royal Holloway, University of London. August 8, 2003.
Madsen KM, Hviid A, Vestergaard M, et al. A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. 2002 Nov 7. 347(19):1477-82. [Medline].
DeStefano F, Bhasin TK, Thompson WW, Yeargin-Allsopp M, Boyle C. Age at first measles-mumps-rubella vaccination in children with autism and school-matched control subjects: a population-based study in metropolitan atlanta. Pediatrics. 2004 Feb. 113(2):259-66. [Medline].
Hitti M. Vaccine Court Rejects Autism Claims. WebMD Health News. February 1, 2009. [Full Text].
Omer SB, Salmon DA, Orenstein WA, deHart MP, Halsey N. Vaccine refusal, mandatory immunization, and the risks of vaccine-preventable diseases. N Engl J Med. 2009 May 7. 360(19):1981-8. [Medline].
American Red Cross, Centers for Disease Control and Prevention, UN Children's Fund, UN Foundation, World Health Organization. Global Measles and Rubella Strategic Plan, 2012-2020. Global Measles and Rubella Strategic Plan, 2012-2020. c2012. Available at http://www.measlesrubellainitiative.org/wp-content/uploads/2013/06/Measles-Rubella-Strategic-Plan.pdf.
Shinefield H, Black S, Digilio L, et al. Evaluation of a quadrivalent measles, mumps, rubella and varicella vaccine in healthy children. Pediatr Infect Dis J. 2005 Aug. 24(8):665-9. [Medline].
[Guideline] Centers for Disease Control and Prevention. Recommended adult immunization schedule---United States, 2009. MMWR Morb Mortal Wkly Rep. 2008. 57(53):[Full Text].
Klein NP, Fireman B, Yih WK, Lewis E, Kulldorff M, Ray P, et al. Measles-mumps-rubella-varicella combination vaccine and the risk of febrile seizures. Pediatrics. 2010 Jul. 126(1):e1-8. [Medline].
[Guideline] Marin M, Broder KR, Temte JL, Snider DE, Seward JF. Use of combination measles, mumps, rubella, and varicella vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2010 May 7. 59:1-12. [Medline]. [Full Text].
Gellis SE. Rubella (German measles). Fitzpatrick's Dermatology in General Medicine. New York, NY: McGraw-Hill; 1999. Vol 2: 2395-8.
Georges P, ed. Rubella. 1997 Redbook: Report of the Committee on Infectious Diseases. Elk Grove Village, Ill: American Academy of Pediatrics; 1997. 456-62.
Lennette EH, Schmidt NJ. Diagnostic Procedures for Viral and Rickettsial Infections. 7th ed. Washington, DC: American Public Health Association; 1979. 725-66.
Mandell GL, Bennett JE, Dolan R, eds. Principles and Practice of Infectious Diseases. 5th ed. Philadelphia, Pa: WB Saunders; 2000. 1708-14.
Weedon D, Strutton G. Skin Pathology. Edinburgh, Scotland: Churchill Livingston; 1997. 597.