Severe Adenovirus Pneumonia Followed by Bacterial Septicaemia: Relevance of Co-Infections in Allogeneic Hematopoietic Stem Cell Transplantation.

Infections are one of the major complications after allogeneic stem cell transplantation (allo-SCT). Disseminated infections with human adenoviruses species A, B or C are associated with a lethality of 24 to 36 %. Fatal outcome is usually observed with high viral loads in blood (median peak HAdV DNAemia 10(8) copies/mL). Here we report two adult patients with disseminated infection with human adenovirus C2 after allo-SCT. Interestingly, both patients developed bacterial septicaemia following the disseminated HAdV infection. Despite lower peak adenoviral loads in blood (<106 copies/mL) than usually reported for fatal cases of HAdV infection and broad spectrum antimicrobial therapy both patients experienced a rapidly fatal outcome. These cases shared the following similarities: disseminated adenovirus infection, adenovirus pneumonia, neurological symptoms and bacterial septicaemia. This suggests that in patients undergoing allo-SCT, viral bacterial co-infections worsen the clinical outcomes.