Congenital rubella syndrome: a review of laboratory data from 2002 to 2011

Rubella infection in pregnant women during the first trimester of pregnancy can lead to fetal anomalies, commonly known as congenital rubella syndrome (CRS). The objective of our study was to analyze the serological test results among infants suspected of having CRS aged < or = 12 months compared with their clinical status. Between January 2002 and December 2011, 3,279 serum samples from infants aged < or = 12 months from government hospitals in Malaysia were examined for rubella specific IgM and IgG antibodies using a Axsym, automated analyzer (Abbott Laboratories). Forty-eight samples were positive for rubella specific IgM antibodies and 494 samples were positive for rubella specific IgG antibodies. These were then age stratified and their clinical history reviewed for any CRS symptoms. Fifteen of 38 rubella IgM positive infants (39.5%) aged < 3 months, had a clinical appearance compatible with CRS. However, only 1 IgM positive infant aged 3 to 6 months and one infant aged 7 to 11 months had clinical appearance compatible with CRS. The most common abnormal findings in these cases were congenital heart defects and cataracts. Forty-eight point eight percent of IgM positive cases and 53.1% of IgG positive cases, had inadequate information in the chart to determine the presence of CRS. Clinical findings and timely laboratory diagnosis to determine the presence of CRS are important in infants born with congenital defects. Physicians should also be aware of the appropriate interpretation of these findings.