Diagnostic value of quantitative PCR for adenovirus detection in stool samples as compared with antigen detection and cell culture in haematopoietic stem cell transplant recipients

Adenovirus (AdV) infections constitute a significant cause of morbidity and mortality during haematopoietic stem cell transplantation. Recent guidelines recommend repeated screening for AdV in whole blood (WB), with quantitative PCR (qPCR) as the reference standard. Despite pre-emptive antiviral treatment based on qPCR in WB, the mortality rate after disseminated AdV infection remains very high. The aim of our study was to advance early screening for AdV, using a standardized method, so as to enable the earlier initiation of antiviral treatment or adoptive immunotherapy. The diagnostic value of AdV DNA quantification in stool samples was investigated retrospectively and compared with antigen detection and cell culture in 21 patients with AdV infection, from 182 patients followed in the Transplant Unit of Nancy University Hospital Centre, including 18 patients with systemic infection. In 16/18 patients with positive AdV viraemia, AdV DNA was present in stool samples earlier than in WB (median, 42 days; range, 3–199 days), whereas both antigen detection and cell culture were still negative for 11/18 patients with systemic AdV infection. The course of AdV viral loads in stool samples was predictive of adenoviraemia (sensitivity, 89%). Very late and lethal AdV infections were observed in cord blood transplant recipients, and would have been detected much earlier with the use of qPCR on stool samples. This study confirmed that quantification of AdV in stool samples by qPCR is beneficial for the management of transplant recipients, with or without antigen detection.