If Biliary Atresia Is a Disease Starting In Utero: Should We Treat Ongoing Cytomegalovirus Infection or Not?

To the Editor: Recently in this journal, Mysore et al (1) comprehensively reviewed data indicating that the development of biliary atresia (BA) starts in utero. Cytomegalovirus (CMV) infection was described as one of several possible etiologic factors and a recent publication suggesting benefits of antiviral treatment in CMV-infected BA patients was cited (2). In fact, in a European multicenter survey, 7 out of 15 responding pediatric surgeons reported that they use such treatment (3). The incidence of ongoing CMV infection in BA, defined by the detection of CMV-IgM, before or at the time of Kasai procedure seems to vary from 10% in the large UK cohort to 74% in a publication from South Africa (4,5). We reported it to be 38%, that is, significantly higher than in age-matched healthy controls [6% (6)]. When we analyzed stored Guthrie cards, collected at birth to detect inborn errors of metabolism, CMV DNA was detected by PCR in only 1 of 11 CMV-IgM-positive BA patients (7). This would either suggest that CMV infection was acquired after birth or that there was a transient period of intrauterine viremia. Thus, although there are some data suggesting that CMV-IgM BA may be a distinct entity with regard to etiology and outcome of this severe disease (4), the timing of the infection and the exact pathogenetic mechanism remain unclear. A multicentre randomized controlled study on antiviral treatment against CMV for this subgroup of patients, is therefore, needed before we consider adding it to standard of care.