Microbiology - Virology
CMV - PCR
CMV - Retinitis
Congenital CMV - Antenatal
Congenital CMV - Postnatal
PCR - CMV
PCR - Cytomegalovirus
Vitreous fluid or eye aspirate.
CMV encephalitis or meningitis (both rarely occur)
CSF sample minimum volume 0.25mL
Gastrointestinal tract infections (immunocompromised patients)
Fresh tissue sample in PBS or viral transport medium
Antenatal diagnosis of congenital CMV infection
Amniotic fluid - recommended after 21 weeks gestation, however will test earlier.
Fetal risk is dependent on the gestation at which maternal infection occurred, and whether it is primary infection or reactivation/ reinfection. The greatest risks are in first trimester with primary infection. Prenatal diagnosis of fetal infection is performed with CMV nucleic acid tests (generally with PCR) on an amniocentesis sample. For optimal sensitivity and specificity, the amniocentesis needs to be performed >8 weeks after the suspected infection and usually >21 weeks gestation. Earlier amniotic fluid samples have a high falsely negative rate.
Postnatal diagnosis of congenital CMV infection -saliva swab in virus transport medium(preferred), or urine collected within the first 3 weeks of life.
All babies of mothers diagnosed with primary CMV infection during pregnancy, should have CMV testing performed at birth with a CMV PCR of saliva or urine within the first 3 weeks of life. Testing must be performed within the first three weeks of life to distinguish congenital from postnatal CMV infection. To collect, insert a sterile polyester swab into the baby's mouth between the gum and cheek and swirl for several seconds. Do not collect directly after feeding. Wait 1-2 hrs after feeding.
Swab packs are available from the laboratory - see swab guide. If the swab test is positive a 5-10mL urine in sterile pottle should be submittted for confirmation.
Infants with congenital infection shed large amounts of CMV virus in the urine and saliva. If submitting urine it is important to submit a sample within the first three weeks after birth and obtain the PCR result to support that the infection was acquired in utero.
Place specimen in PCR bag.
Cytomegalovirus Nucleic acid extraction, qualitative PCR amplification and detection for samples other than EDTA Blood.
NOTE:For EDTA blood testing see CMV VIRAL LOAD
$203.99 (Exclusive of GST)
For clinical microbiologist or microbiology registrar consultation please contact Virology.
For further guidance in congenital CMV infection please refer to the PDF link below. This 2019 guidance document (RANZCOG) "Prevention of congenital cytomegalovirus (CMV) infection" is endorsed and approved by the Royal Australian and New Zealand College of obstetricians and Gynaecologists.
Prevention of congenital cytomegalovirus (CMV) infection
Urgent testing by arrangement