Good afternoon members, 

I have a strange issue. I have received a 6 weeks old infant, transferred from another hospital, normal vaginal delivery to a G2 P2 mother, with no significant antenatal history(heresay), birth weight being 2.5kg, no other anthropometry available. Baby was discharged but taken to the hospital in view of poor feeding, admitted with a diagnosis of sepsis based on thrombocytopenia(48,000), high CRP but negative culture. Hewas discharged after 5 days of iv cefipime but returned to the hospital after 10 days with breathlessness. He was again investigated, found to be thrombocytopenic and anemic and was transfused with platelets and packed cells, unfortunately using mother's blood. He was also jaundiced (reports not available). The parents got him to our unit at 5.5 weeks, a week after the last transfusion, In our unit, his weight had increased to 2.8 kg, OFC being 33.5cm and length being 47cm. He did not have any petechiae or organomegaly. He is in room air on full feeds. Besides anemia(Hb 10.5 gm%), thrombocytopenia(24,000), Serum bilirubin of 5.5mg% with direct of 3.5mg%, modestly abnormal liver enzymes and a normal CRP. His neurosonogram, abdominal USG and eye examination are normal. He does have sutural overlap. Mother's CMV IgG and IgM are positive. 

The problem is how do I rule out congenital CMV infection in this baby at 5.5 weeks who has been transfused recently with mother's own blood products.

Tricky question. Do you have access to dried blood spots from PKU-testing, or bio-banked blood/serum from the infants, from some around time of delivery? Or is therer bio-banked maternal serum from antenatal blood testing? If either are availabel, you may be able to check serology status from those time points, and such results may guide you.

Maternal serology for CMV. and avidity. If avidity low, it indicates recent infection in mother . PRBC transfusion ( non leuco depleted) and breast milk are the most common causes of postnatal CMV infection. Congenital CMV can be diagnosed in first 2 weeks of life. After that not possible to distinguish between congenital / postnatal CMV infection. 

If the dried blood specimen which is collected at birth is not available, Test urine cmv pcr. If negative, it is negative and search for another reason. If it is positive, repeat it. If still positive, do hearing test, if has hearing loss treat with valgancyclovir.

PCR on dried blood spots from neonatal screening if available but low sensitivity

hearing test... 

 

I would do urine pcr

Hi,

according to your patient history, it is not really possible to diagnose cCMV. If you have DBS and it is positive - fine - you got it, but you also have a chance that it is false-negative (Sensitivity about 84%, but this seems to be highly variable depending on the lab technique, etc.). A urine sample within the first 21 days (better 14d) would be the optimum.

Maybe this reference can help you a little for the future: https://pubmed.ncbi.nlm.nih.gov/29140947/

The hearing test would be interesting as mentioned previously - any update from the patient?

I think others has shown the ways to diff between congenital or postnatal aquired CMV. Right now the other question is:  if there is CMV in the Urin or serolgical Evidence for CMV without CNSdesease: treat (with VGV) or follow up?