Urine viral load and correlation with disease severity in infants with congenital or postnatal cytomegalovirus infection

Abstract Background A correlation between cytomegalovirus (CMV) load in urine and severity of disease in congenitally infected infants has previously been reported. CMV load in postnatally infected infants has not been studied before. Objective To investigate CMV load in urine of infants with postnatal or congenital infection and correlate this with clinical symptoms of CMV disease and cerebral abnormalities. Study design Infants admitted to our NICU between July 2000 and February 2010, and diagnosed with congenital or postnatal CMV infection were included. Clinical symptoms of CMV infection, cranial ultrasonography (cUS) and magnetic resonance imaging (MRI) findings were evaluated. CMV urine loads of postnatally infected infants were analyzed and compared with CMV urine loads of congenitally infected infants. Results Seventeen infants with congenital CMV infection and 45 infants with postnatal CMV infection were included. Thirteen/17 (76%) congenitally infected infants had clinical symptoms of CMV infection at birth and 11/17 (65%) had cerebral abnormalities diagnosed by neuro-imaging. None of the four asymptomatic infants had cerebral abnormalities. Of the postnatally infected infants 43/45 (96%) did not develop any clinical symptoms of CMV infection, but in 23/45 (51%) cerebral abnormalities such as lenticulostriate vasculopathy and germinolytic cysts were identified. The median CMV load in postnatally infected infants was significantly lower than in congenitally infected infants (1.0 × 105 copies/ml versus 8.5 × 106 copies/ml, p < 0.001, respectively). Conclusions CMV load in urine is significantly lower in infants with postnatal CMV infection than in infants with congenital CMV infection irrespective of clinical symptoms of CMV infection or cerebral abnormalities.