Laboratory confirmation of cytomegalovirus (CMV) infection with or without clinical illness:
- Direct detection of CMV, using PCR or viral culture, from urine, saliva, blood or CSF collected from an infant at less than 3 weeks of age. If CMV is detected in saliva, repeat testing should be performed using urine.
- Prenatal diagnosis through direct detection of CMV, using PCR or viral culture, in amniotic fluid.
- Histopathological evidence of CMV inclusion disease from an appropriate clinical specimen, including a post-mortem specimen.
Otherwise unexplained clinical illness consistent with congenital CMV with evidence of CMV infection not meeting the criteria above; for example direct detection of virus in a child older than 3 weeks of age, or positive CMV IgM antibody in fetus or newborn.
Clinical illness includes stillbirth, intrauterine growth retardation, fulminant cytomegalic inclusion disease (jaundice, hepatosplenomegaly, petechial rash, multiple organ involvement) and/or central nervous system findings (microcephaly, motor disability, chorioretinitis, cerebral calcifications). There may be onset of lethargy, respiratory distress or seizures soon after birth.