Quantification of Torque Teno Virus and Epstein-Barr Virus Is of Limited Value for Predicting the Net State of Immunosuppression After Lung Transplantation

Nordén, Rickard; Magnusson, Jesper; Lundin, Anna; Tang, Ka-Wei; Nilsson, Staffan; Lindh, Magnus; Andersson, Lars-Magnus; Riise, Gerdt C; Westin, Johan

Bacterial infection was defined as a positive bacterial culture in conjunction with symptoms of clinical infection or, in the absence of positive culture, symptoms consistent with bacterial infection that was treated with antibiotics. Fungal infection was defined as significant presence of fungi in culture from a sterile location in conjunction with symptoms of infection according to the European Organization for Research and Treatment of Cancer (EORTC) criteria [25] . VRTI or Mycoplasma pneumoniae infection was defined as detection of a pathogen by multiplex real-time PCR in NPH or BAL. CMV viremia was defined as elevated levels of CMV-DNA that prompted antiviral therapy. CMV-seronegative recipients were considered to have viremia if CMV-DNA was detected, whereas recipients seropositive for CMV prior to transplantation where considered to have CMV viremia only if the level was above 3.0 log10 (1000) copies/mL. To distinguish milder infections from more severe infectious events, a subgroup of events requiring initial intravenous antimicrobial (antibacterial, antiviral, or antifungal) therapy were defined as severe. Acute rejection was defined as either a lung biopsy showing rejection of ISHLT grade 1A or higher [26] or, in the absence of a biopsy, physical (increased need for oxygen) and radiological findings (progressive infiltrate without signs of infection) consistent with acute rejection followed by a prompt response to high-dose (1 g/d for 3 consecutive days) corticosteroid therapy (methylprednisolone).