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

Abstract

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.

Adenovirus Infections in Immunocompetent and Immunocompromised Patients

“…In a study performed at our center, viremia occurred in more than 70% of pediatric patients with these findings, whereas none of the individuals with maximum viral loads below the indicated threshold experienced invasive HAdV infection (69). These observations were recently confirmed by other groups (188,189) and are expected to have important implications for future diagnostic and treatment strategies.…”

“…Additionally, there is growing evidence that HAdV detection and surveillance of virus proliferation kinetics in stool provide early information on impending invasive infection and HAdV disease (69,188,189). Viral persistence in the GI tract and shedding of HAdV into feces are common findings which, in previous experience, occur in more than one-third of pediatric patients after allo-HSCT and may not necessarily be associated with clinical symptoms of intestinal infection (69).…”

“…In this regard, the orally bioavailable and less nephrotoxic lipid ester of cidofovir, brincidofovir, could provide an important improvement of current antiviral therapies. Preliminary data from ongoing studies are promising, and an international therapy trial with brincidofovir in transplant recipients displaying intestinal HAdV infection, who have an elevated risk of viremia and disseminated disease (69,188,189), is currently in preparation. This study is expected to provide important evidence for the efficacy of early preemptive virustatic treatment.…”

Broad-Range PCR-Electrospray Ionization Mass Spectrometry for Detection and Typing of Adenovirus and Other Opportunistic Viruses in Stem Cell Transplant Patients

“…Almost all patients who experience systemic adenovirus infection have detectable viral DNA in stool specimens before the onset of viremia, suggesting that the intestinal tract may be a common source of virus dissemination and that virus detection in stool could be used to identify patients with adenovirus reactivation. However, only patients with high viral loads in stool (exceeding 10 6 copies per gram of stool) are at risk for systemic infection (13,14). In the analyses of HSCT patient samples reported here, the Viral IC Spectrum assay run on the PLEX-ID system detected adenovirus in stool samples far below this threshold and may be sensitive enough for screening of patients at risk for adenovirus infection.…”

“…Following pediatric HSCT, immunosuppression may lead to uncontrolled reactivation of digestive adenoviruses that often precede blood dissemination (13,14).…”