OSCE station Viva Congenital CMV
A structured viva for neonatal and paediatric trainees on confirming, evaluating, treating and monitoring a newborn infant with suspected congenital CMV disease.
A baby boy born at 38 weeks’ gestation has a birth weight below the 10th percentile for gestational age. On day 1 he has a petechial rash and hepatosplenomegaly, and his platelet count is low. He is feeding orally.
Suggested time: 10 minutes
Questions
Which test would you send to confirm or exclude congenital CMV, and by when?
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- CMV testing of urine (PCR or culture). Identification of CMV in the urine is the gold standard.
- Within the first 21 days after birth. Detection after 3 weeks cannot distinguish congenital infection from infection acquired at or after birth.
- Saliva is an acceptable initial test in a term infant, but a positive result should be confirmed by urine obtained by 21 days of age.
- He meets the HT plus expanded testing criteria: birth weight below the 10th percentile, petechial rash, hepatosplenomegaly and thrombocytopenia.
The test is positive. What does your initial evaluation include?
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- Thorough physical examination: growth parameters including head circumference, complete neurologic examination, skin (petechiae, jaundice), abdomen (hepatosplenomegaly).
- Liver function tests and a complete blood cell count.
- Cranial ultrasonography. Head MRI (noncontrast) if abnormalities are found on neurologic examination or cranial ultrasonography.
- Diagnostic audiology assessment, completed by 12 weeks of age.
- Ophthalmologic evaluation.
- Paediatric infectious diseases consultation to evaluate for antiviral treatment, with joint management if therapy is given.
Cranial ultrasonography shows intracranial calcifications. How would you classify his disease, and what would you recommend?
(a) What would change if he developed necrotising enterocolitis?
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- Moderate to severe cCMV disease. Central nervous system involvement (radiographic abnormalities such as intracerebral calcifications) meets the criterion, and he also has more than 2 manifestations.
- Valganciclovir 32 mg/kg/d divided in 2 doses, orally. Begin as soon as feasible within the first 13 weeks after birth (through 12 weeks, 6 days following birth) and continue for 6 months.
- (a) If he cannot absorb medications reliably from the gut (for example, necrotising enterocolitis), intravenous ganciclovir 12 mg/kg/day in 2 divided doses can be used initially. All or most of the treatment should be completed with valganciclovir.
How would you monitor treatment?
(a) What would you do if his absolute neutrophil count were reproducibly below 500 cells/mm³?
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- Absolute neutrophil count weekly for 6 weeks, at week 8, then monthly until the end of treatment. Transaminases monthly until the end of treatment.
- Neutropenia is more common in the first 4 to 6 weeks, and can come from the CMV infection itself as well as from therapy.
- Renal toxicity is possible when potentially nephrotoxic medications are given with ganciclovir in neonates.
- (a) Hold therapy and resume when counts recover above 750 cells/mm³, or give granulocyte colony-stimulating factor once daily for 1 to 3 consecutive days.
The parents ask whether 6 months of treatment will protect his hearing in the long term. What does the evidence allow you to say?
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- In the CASG trial of 6 weeks versus 6 months of valganciclovir, there was no difference in best ear hearing at 6 months. More children in the 6-month group maintained normal hearing thresholds or had improved total ear hearing at 12 months, maintained at 24 months. They also had higher language composite and receptive communication scores at 24 months.
- Limitations: possible confounding from serous otitis media, and follow-up of about 2 years.
- In a longer-term report (76 children, followed to a median age of 11 to 13 years), most with cCMV disease and early SNHL went on to severe to profound hearing changes, whether or not they had 6 weeks of ganciclovir.
- It remains unclear whether 6 months gives better long-term outcomes, or a transient improvement that could matter during a critical period of language development.
- Counsel honestly. Lifelong hearing surveillance in each ear and an early intervention referral apply whatever happens.
Based on: Tesini BL, et al; American Academy of Pediatrics. Care of the Infant With Congenital Cytomegalovirus Infection: Clinical Report. Pediatrics. 2026;158(4):e2026078595.
Tiny Taught · Neonatal & Paediatric Education
Teaching material for exam preparation. Doses and thresholds are for orientation only; follow local guidelines.