Elecsys® Rubella IgG

Immunoassay for the quantitative determination of IgG-antibodies against rubella virus

Elecsys® Rubella IgG
Immunoassay for the quantitative determination of IgG-antibodies against rubella virus

Rubella virus causes German measles, a mild rash disease which commonly occurs during childhood. It is highly contagious and mainly transmitted by the respiratory route.1 Rubella can also occur vertically from an infected mother to her child.1 Postnatal infection is rarely associated with complications, however, primary infection mainly during early pregnancy is a serious condition, as it may cause miscarriages or congenital rubella syndrome (CRS). CRS includes blindness, deafness, congenital heart disease and mental retardation.1

Today’s vaccination programs have considerably reduced the incidence of acute rubella and CRS.2 Since rubella may present atypically or with non-specific symptoms and signs that may be caused by other viruses which do not have a teratogenic potential, it is important that the clinical diagnosis be confirmed by laboratory tests, particularly during pregnancy.3

Seroconversion of specific rubella antibodies or a significant rise of the IgG titer strongly supports the diagnosis of acute rubella infection.3 The presence of IgG antibodies to rubella virus indicates a previous exposure either by vaccination or prior rubella infection and suggests immunity.3 The quantitative determination of specific IgG is used to determine the immune status to rubella.3

Elecsys® Rubella IgG

Elecsys® Rubella IgG4

  • Systems

    cobas e 411 analyzer, cobas e 601 / cobas e 602 modules, cobas e 402 / cobas e 801 analytical units

  • Testing Time

    18 minutes

  • Test principle

    One-step double antigen sandwich assay (DAGS) / γ-capture assay

  • Calibration

    2-point

  • Interpretation

    <10 IU/mL = non-reactive
    ≥10 IU/mL = reactive    

  • Sample material

    Serum collected using standard sampling tubes or tubes containing separating gel. Li-heparin, Na-heparin, K2-EDTA, K3-EDTA and Na-citrate plasma. Plasma tubes containing separating gel can be used.

  • Sample volume

    10 μL cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    6 μL cobas e 402 / cobas e 801 analytical units

  • Onboard stability

    14 days for cobas e 411 analyzer, cobas e 601 / cobas e 602 modules
    16 weeks for cobas e 402 / cobas e 801 analytical units

  • Intermediate precision

    cobas e 411 analyzer: CV 3.4 – 3.8 %    
    cobas e 601 / 602 modules: CV 3.2 – 3.3 %     
    cobas e 402 / cobas e 801 analytical units: CV 3.9 – 4.6 %

  • Relative sensitivity

    100 % (n = 514) lower 95 % C.I.: 99.4 %
    99.9 % (n = 978) lower 95 % C.I.: 99.5 %
    100 % (n = 120) lower 95 % C.I.: 97.5 %
    100 % (n = 20)    

  • Relative specificity

    97.4 % (n = 38)
    100 % (n = 18)
    100 % (n = 78) lower 95 % C.I.: 96.2 %
    100 % (n = 769) lower 95 % C.I.: 99.6 %    

Please note: The measured anti‑Rubella IgG value of a patient’s sample can vary depending on the testing procedure used. The laboratory finding must therefore always contain a statement on the Rubella IgG assay used. Anti‑Rubella IgG values determined on patient samples by different testing procedures cannot be directly compared with one another and could be the cause of erroneous medical interpretation.

References

  1. Best JM. Rubella. Seminars in Fetal & Neonatal Medicine. 2007; 12:182e192.
  2. The Measles & Rubella initiative. 2020 Annual Summary.  [Internet; updated 2022 Aug; cited 2022 Oct 24]. Available from: https://s3.amazonaws.com/wp-agility2/measles/wp-content/uploads/2022/08/MRI-2020-Annual-Summary.pdf
  3. Best JM, Enders G. Rubella Viruses. Laboratory Diagnosis of Rubella and Congenital Rubella - Chapter 3. Elsevier B.V. 2007;39-77.
  4. Elecsys® Rubella IgG (#04618793190, #07027770190) method sheet 2022, V. 11.0 and 6.0.