Analysis index

Antibody demonstration: 1 ml serum, 1 ml CSF

IgG avidity: 1 ml serum

PCR: 3 ml morning urine, 5 ml EDTA-blood or plasma, 1 ml serum, 3 ml amniotic fluid, 1 ml CSF, 1 ml breast milk, cervical smear, 1 ml pharyngeal secretion, 1 ml BAL, 1 ml stool

IgG: < 5,9 AE/ml

IgM: < 0,85 – 1,0 index

IgG-avidity: > 50 % – 59 %

PCR: < 100 IU/ml (detection limit, blood, CSF)

< 500 IU/ml (detection limit, urine and other materials)

Antibody demonstration: On suspicion of primary or reactivated CMV infection, connatal CMV (detection of CMV-IgM in the fetal blood). Only 60 % – 70 % of pregnant women with primary CMV infection develop IgM-antibodies. With IgG-levels > 5,9 AE/ml and negative IgM, a previous primary infection has to be assumed (Exception in babies due to possible passive immunity).

Antibody avidity: Distinction between active and previous CMV infection. A lower IgG-avidity is indicative for an acute infection. 

PCR: Primary infection during pregnancy (urine, cervical smear), connatal infection, newborns, before and after transplants, reactivated infection in immune-deficient patients

Incubation time 20 – 30 days.

Primary infection: Mainly without symptoms but also with mononucleosis-like clinical picture, slight hepatitis, pneumonia, splenomegaly, retinitis.

Reactivation: Often asymptomatic course.

Infection in immunosuppressed patients (after transplants): Pneumonia, hepatitis, myocarditis/pericarditis, meningitis, retinitis, encephalitis, colitis, transplant rejection.

Connatal infection: Every other pregnant woman has no CMV immunity and is therefore at risk of primary infection. Overall, it can be expected that one in 1000 births results in a child with problems caused by CMV. 2 % – 3 % of pregnant women develop a primary infection. In approximately 40 % of cases, there is consequent transplacental transmission. The majority of prenatally infected children are clinically healthy at the time of birth. Only 5 % – 10 % of them have serious clinical symptoms such as hepatosplenomegaly, hemolytic anemia, thrombocytopenia, chorioretinitis, atypical pneumonia, and microcephaly. As they get older, a further 10 % will develop mental retardation, speech- and hearing disorders and others. Diagnostics by testing for CMV-IgG and CMV-IgM, CMV-IgG-avidity test, CMV-dna in the chorion villus sampling, in the amniotic fluid, in placental tissue, in stool and in urine via PCR.